tor-browser

The Tor Browser
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opt.c (88061B)


      1 /*
      2 * AVOptions
      3 * Copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
      4 *
      5 * This file is part of FFmpeg.
      6 *
      7 * FFmpeg is free software; you can redistribute it and/or
      8 * modify it under the terms of the GNU Lesser General Public
      9 * License as published by the Free Software Foundation; either
     10 * version 2.1 of the License, or (at your option) any later version.
     11 *
     12 * FFmpeg is distributed in the hope that it will be useful,
     13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
     14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     15 * Lesser General Public License for more details.
     16 *
     17 * You should have received a copy of the GNU Lesser General Public
     18 * License along with FFmpeg; if not, write to the Free Software
     19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
     20 */
     21 
     22 /**
     23 * @file
     24 * AVOptions
     25 * @author Michael Niedermayer <michaelni@gmx.at>
     26 */
     27 
     28 #include "avutil.h"
     29 #include "avassert.h"
     30 #include "avstring.h"
     31 #include "channel_layout.h"
     32 #include "dict.h"
     33 #include "eval.h"
     34 #include "log.h"
     35 #include "mem.h"
     36 #include "parseutils.h"
     37 #include "pixdesc.h"
     38 #include "mathematics.h"
     39 #include "opt.h"
     40 #include "samplefmt.h"
     41 #include "bprint.h"
     42 #include "version.h"
     43 
     44 #include <float.h>
     45 
     46 #define TYPE_BASE(type) ((type) & ~AV_OPT_TYPE_FLAG_ARRAY)
     47 
     48 const AVOption *av_opt_next(const void *obj, const AVOption *last)
     49 {
     50    const AVClass *class;
     51    if (!obj)
     52        return NULL;
     53    class = *(const AVClass**)obj;
     54    if (!last && class && class->option && class->option[0].name)
     55        return class->option;
     56    if (last && last[1].name)
     57        return ++last;
     58    return NULL;
     59 }
     60 
     61 static const struct {
     62    size_t      size;
     63    const char *name;
     64 } opt_type_desc[] = {
     65    [AV_OPT_TYPE_FLAGS]         = { sizeof(unsigned),       "<flags>" },
     66    [AV_OPT_TYPE_INT]           = { sizeof(int),            "<int>" },
     67    [AV_OPT_TYPE_INT64]         = { sizeof(int64_t),        "<int64>" },
     68    [AV_OPT_TYPE_UINT]          = { sizeof(unsigned),       "<unsigned>" },
     69    [AV_OPT_TYPE_UINT64]        = { sizeof(uint64_t),       "<uint64>" },
     70    [AV_OPT_TYPE_DOUBLE]        = { sizeof(double),         "<double>" },
     71    [AV_OPT_TYPE_FLOAT]         = { sizeof(float),          "<float>" },
     72    [AV_OPT_TYPE_STRING]        = { sizeof(char *),         "<string>" },
     73    [AV_OPT_TYPE_RATIONAL]      = { sizeof(AVRational),     "<rational>" },
     74    [AV_OPT_TYPE_BINARY]        = { sizeof(uint8_t *),      "<binary>" },
     75    [AV_OPT_TYPE_DICT]          = { sizeof(AVDictionary *), "<dictionary>" },
     76    [AV_OPT_TYPE_IMAGE_SIZE]    = { sizeof(int[2]),         "<image_size>" },
     77    [AV_OPT_TYPE_VIDEO_RATE]    = { sizeof(AVRational),     "<video_rate>" },
     78    [AV_OPT_TYPE_PIXEL_FMT]     = { sizeof(int),            "<pix_fmt>" },
     79    [AV_OPT_TYPE_SAMPLE_FMT]    = { sizeof(int),            "<sample_fmt>" },
     80    [AV_OPT_TYPE_DURATION]      = { sizeof(int64_t),        "<duration>" },
     81    [AV_OPT_TYPE_COLOR]         = { sizeof(uint8_t[4]),     "<color>" },
     82    [AV_OPT_TYPE_CHLAYOUT]      = { sizeof(AVChannelLayout),"<channel_layout>" },
     83    [AV_OPT_TYPE_BOOL]          = { sizeof(int),            "<boolean>" },
     84 };
     85 
     86 // option is plain old data
     87 static int opt_is_pod(enum AVOptionType type)
     88 {
     89    switch (type) {
     90    case AV_OPT_TYPE_FLAGS:
     91    case AV_OPT_TYPE_INT:
     92    case AV_OPT_TYPE_INT64:
     93    case AV_OPT_TYPE_DOUBLE:
     94    case AV_OPT_TYPE_FLOAT:
     95    case AV_OPT_TYPE_RATIONAL:
     96    case AV_OPT_TYPE_UINT64:
     97    case AV_OPT_TYPE_IMAGE_SIZE:
     98    case AV_OPT_TYPE_PIXEL_FMT:
     99    case AV_OPT_TYPE_SAMPLE_FMT:
    100    case AV_OPT_TYPE_VIDEO_RATE:
    101    case AV_OPT_TYPE_DURATION:
    102    case AV_OPT_TYPE_COLOR:
    103    case AV_OPT_TYPE_BOOL:
    104    case AV_OPT_TYPE_UINT:
    105        return 1;
    106    }
    107    return 0;
    108 }
    109 
    110 static uint8_t opt_array_sep(const AVOption *o)
    111 {
    112    const AVOptionArrayDef *d = o->default_val.arr;
    113    av_assert1(o->type & AV_OPT_TYPE_FLAG_ARRAY);
    114    return (d && d->sep) ? d->sep : ',';
    115 }
    116 
    117 static void *opt_array_pelem(const AVOption *o, void *array, unsigned idx)
    118 {
    119    av_assert1(o->type & AV_OPT_TYPE_FLAG_ARRAY);
    120    return (uint8_t *)array + idx * opt_type_desc[TYPE_BASE(o->type)].size;
    121 }
    122 
    123 static unsigned *opt_array_pcount(const void *parray)
    124 {
    125    return (unsigned *)((const void * const *)parray + 1);
    126 }
    127 
    128 static void opt_free_elem(enum AVOptionType type, void *ptr)
    129 {
    130    switch (TYPE_BASE(type)) {
    131    case AV_OPT_TYPE_STRING:
    132    case AV_OPT_TYPE_BINARY:
    133        av_freep(ptr);
    134        break;
    135 
    136    case AV_OPT_TYPE_DICT:
    137        av_dict_free((AVDictionary **)ptr);
    138        break;
    139 
    140    case AV_OPT_TYPE_CHLAYOUT:
    141        av_channel_layout_uninit((AVChannelLayout *)ptr);
    142        break;
    143 
    144    default:
    145        break;
    146    }
    147 }
    148 
    149 static void opt_free_array(const AVOption *o, void *parray, unsigned *count)
    150 {
    151    for (unsigned i = 0; i < *count; i++)
    152        opt_free_elem(o->type, opt_array_pelem(o, *(void **)parray, i));
    153 
    154    av_freep(parray);
    155    *count = 0;
    156 }
    157 
    158 /**
    159 * Perform common setup for option-setting functions.
    160 *
    161 * @param require_type when non-0, require the option to be of this type
    162 * @param ptgt         target object is written here
    163 * @param po           the option is written here
    164 * @param pdst         pointer to option value is written here
    165 */
    166 static int opt_set_init(void *obj, const char *name, int search_flags,
    167                        int require_type,
    168                        void **ptgt, const AVOption **po, void **pdst)
    169 {
    170    const AVOption *o;
    171    void *tgt;
    172 
    173    o = av_opt_find2(obj, name, NULL, 0, search_flags, &tgt);
    174    if (!o || !tgt)
    175        return AVERROR_OPTION_NOT_FOUND;
    176 
    177    if (o->flags & AV_OPT_FLAG_READONLY)
    178        return AVERROR(EINVAL);
    179 
    180    if (require_type && (o->type != require_type)) {
    181        av_log(obj, AV_LOG_ERROR,
    182               "Tried to set option '%s' of type %s from value of type %s, "
    183               "this is not supported\n", o->name, opt_type_desc[o->type].name,
    184               opt_type_desc[require_type].name);
    185        return AVERROR(EINVAL);
    186    }
    187 
    188    if (!(o->flags & AV_OPT_FLAG_RUNTIME_PARAM)) {
    189        unsigned *state_flags = NULL;
    190        const AVClass *class;
    191 
    192        // try state flags first from the target (child), then from its parent
    193        class = *(const AVClass**)tgt;
    194        if (
    195 #if LIBAVUTIL_VERSION_MAJOR < 60
    196            class->version >= AV_VERSION_INT(59, 41, 100) &&
    197 #endif
    198            class->state_flags_offset)
    199            state_flags = (unsigned*)((uint8_t*)tgt + class->state_flags_offset);
    200 
    201        if (!state_flags && obj != tgt) {
    202            class = *(const AVClass**)obj;
    203            if (
    204 #if LIBAVUTIL_VERSION_MAJOR < 60
    205                class->version >= AV_VERSION_INT(59, 41, 100) &&
    206 #endif
    207                class->state_flags_offset)
    208                state_flags = (unsigned*)((uint8_t*)obj + class->state_flags_offset);
    209        }
    210 
    211        if (state_flags && (*state_flags & AV_CLASS_STATE_INITIALIZED)) {
    212            av_log(obj, AV_LOG_ERROR, "Option '%s' is not a runtime option and "
    213                   "so cannot be set after the object has been initialized\n",
    214                   o->name);
    215 #if LIBAVUTIL_VERSION_MAJOR >= 60
    216            return AVERROR(EINVAL);
    217 #endif
    218        }
    219    }
    220 
    221    if (o->flags & AV_OPT_FLAG_DEPRECATED)
    222        av_log(obj, AV_LOG_WARNING, "The \"%s\" option is deprecated: %s\n", name, o->help);
    223 
    224    if (po)
    225        *po   = o;
    226    if (ptgt)
    227        *ptgt = tgt;
    228    if (pdst)
    229        *pdst = ((uint8_t *)tgt) + o->offset;
    230 
    231    return 0;
    232 }
    233 
    234 static AVRational double_to_rational(double d)
    235 {
    236     AVRational r = av_d2q(d, 1 << 24);
    237     if ((!r.num || !r.den) && d)
    238         r = av_d2q(d, INT_MAX);
    239     return r;
    240 }
    241 
    242 static int read_number(const AVOption *o, const void *dst, double *num, int *den, int64_t *intnum)
    243 {
    244    switch (TYPE_BASE(o->type)) {
    245    case AV_OPT_TYPE_FLAGS:
    246        *intnum = *(unsigned int*)dst;
    247        return 0;
    248    case AV_OPT_TYPE_PIXEL_FMT:
    249        *intnum = *(enum AVPixelFormat *)dst;
    250        return 0;
    251    case AV_OPT_TYPE_SAMPLE_FMT:
    252        *intnum = *(enum AVSampleFormat *)dst;
    253        return 0;
    254    case AV_OPT_TYPE_BOOL:
    255    case AV_OPT_TYPE_INT:
    256        *intnum = *(int *)dst;
    257        return 0;
    258    case AV_OPT_TYPE_UINT:
    259        *intnum = *(unsigned int *)dst;
    260        return 0;
    261    case AV_OPT_TYPE_DURATION:
    262    case AV_OPT_TYPE_INT64:
    263    case AV_OPT_TYPE_UINT64:
    264        *intnum = *(int64_t *)dst;
    265        return 0;
    266    case AV_OPT_TYPE_FLOAT:
    267        *num = *(float *)dst;
    268        return 0;
    269    case AV_OPT_TYPE_DOUBLE:
    270        *num = *(double *)dst;
    271        return 0;
    272    case AV_OPT_TYPE_RATIONAL:
    273        *intnum = ((AVRational *)dst)->num;
    274        *den    = ((AVRational *)dst)->den;
    275        return 0;
    276    case AV_OPT_TYPE_CONST:
    277        *intnum = o->default_val.i64;
    278        return 0;
    279    }
    280    return AVERROR(EINVAL);
    281 }
    282 
    283 static int write_number(void *obj, const AVOption *o, void *dst, double num, int den, int64_t intnum)
    284 {
    285    const enum AVOptionType type = TYPE_BASE(o->type);
    286 
    287    if (type != AV_OPT_TYPE_FLAGS &&
    288        (!den || o->max * den < num * intnum || o->min * den > num * intnum)) {
    289        num = den ? num * intnum / den : (num && intnum ? INFINITY : NAN);
    290        av_log(obj, AV_LOG_ERROR, "Value %f for parameter '%s' out of range [%g - %g]\n",
    291               num, o->name, o->min, o->max);
    292        return AVERROR(ERANGE);
    293    }
    294    if (type == AV_OPT_TYPE_FLAGS) {
    295        double d = num*intnum/den;
    296        if (d < -1.5 || d > 0xFFFFFFFF+0.5 || (llrint(d*256) & 255)) {
    297            av_log(obj, AV_LOG_ERROR,
    298                   "Value %f for parameter '%s' is not a valid set of 32bit integer flags\n",
    299                   num*intnum/den, o->name);
    300            return AVERROR(ERANGE);
    301        }
    302    }
    303 
    304    switch (type) {
    305    case AV_OPT_TYPE_PIXEL_FMT:
    306        *(enum AVPixelFormat *)dst = llrint(num / den) * intnum;
    307        break;
    308    case AV_OPT_TYPE_SAMPLE_FMT:
    309        *(enum AVSampleFormat *)dst = llrint(num / den) * intnum;
    310        break;
    311    case AV_OPT_TYPE_BOOL:
    312    case AV_OPT_TYPE_FLAGS:
    313    case AV_OPT_TYPE_INT:
    314    case AV_OPT_TYPE_UINT:
    315        *(int *)dst = llrint(num / den) * intnum;
    316        break;
    317    case AV_OPT_TYPE_DURATION:
    318    case AV_OPT_TYPE_INT64:{
    319        double d = num / den;
    320        if (intnum == 1 && d == (double)INT64_MAX) {
    321            *(int64_t *)dst = INT64_MAX;
    322        } else
    323            *(int64_t *)dst = llrint(d) * intnum;
    324        break;}
    325    case AV_OPT_TYPE_UINT64:{
    326        double d = num / den;
    327        // We must special case uint64_t here as llrint() does not support values
    328        // outside the int64_t range and there is no portable function which does
    329        // "INT64_MAX + 1ULL" is used as it is representable exactly as IEEE double
    330        // while INT64_MAX is not
    331        if (intnum == 1 && d == (double)UINT64_MAX) {
    332            *(uint64_t *)dst = UINT64_MAX;
    333        } else if (d > INT64_MAX + 1ULL) {
    334            *(uint64_t *)dst = (llrint(d - (INT64_MAX + 1ULL)) + (INT64_MAX + 1ULL))*intnum;
    335        } else {
    336            *(uint64_t *)dst = llrint(d) * intnum;
    337        }
    338        break;}
    339    case AV_OPT_TYPE_FLOAT:
    340        *(float *)dst = num * intnum / den;
    341        break;
    342    case AV_OPT_TYPE_DOUBLE:
    343        *(double    *)dst = num * intnum / den;
    344        break;
    345    case AV_OPT_TYPE_RATIONAL:
    346    case AV_OPT_TYPE_VIDEO_RATE:
    347        if ((int) num == num)
    348            *(AVRational *)dst = (AVRational) { num *intnum, den };
    349        else
    350            *(AVRational *)dst = double_to_rational(num * intnum / den);
    351        break;
    352    default:
    353        return AVERROR(EINVAL);
    354    }
    355    return 0;
    356 }
    357 
    358 static int hexchar2int(char c) {
    359    if (c >= '0' && c <= '9')
    360        return c - '0';
    361    if (c >= 'a' && c <= 'f')
    362        return c - 'a' + 10;
    363    if (c >= 'A' && c <= 'F')
    364        return c - 'A' + 10;
    365    return -1;
    366 }
    367 
    368 static int set_string_binary(void *obj, const AVOption *o, const char *val, uint8_t **dst)
    369 {
    370    int *lendst = (int *)(dst + 1);
    371    uint8_t *bin, *ptr;
    372    int len;
    373 
    374    av_freep(dst);
    375    *lendst = 0;
    376 
    377    if (!val || !(len = strlen(val)))
    378        return 0;
    379 
    380    if (len & 1)
    381        return AVERROR(EINVAL);
    382    len /= 2;
    383 
    384    ptr = bin = av_malloc(len);
    385    if (!ptr)
    386        return AVERROR(ENOMEM);
    387    while (*val) {
    388        int a = hexchar2int(*val++);
    389        int b = hexchar2int(*val++);
    390        if (a < 0 || b < 0) {
    391            av_free(bin);
    392            return AVERROR(EINVAL);
    393        }
    394        *ptr++ = (a << 4) | b;
    395    }
    396    *dst    = bin;
    397    *lendst = len;
    398 
    399    return 0;
    400 }
    401 
    402 static int set_string(void *obj, const AVOption *o, const char *val, uint8_t **dst)
    403 {
    404    av_freep(dst);
    405    if (!val)
    406        return 0;
    407    *dst = av_strdup(val);
    408    return *dst ? 0 : AVERROR(ENOMEM);
    409 }
    410 
    411 #define DEFAULT_NUMVAL(opt) ((opt->type == AV_OPT_TYPE_INT64 || \
    412                              opt->type == AV_OPT_TYPE_UINT64 || \
    413                              opt->type == AV_OPT_TYPE_CONST || \
    414                              opt->type == AV_OPT_TYPE_FLAGS || \
    415                              opt->type == AV_OPT_TYPE_UINT  || \
    416                              opt->type == AV_OPT_TYPE_INT)     \
    417                             ? opt->default_val.i64             \
    418                             : opt->default_val.dbl)
    419 
    420 static int set_string_number(void *obj, void *target_obj, const AVOption *o, const char *val, void *dst)
    421 {
    422    const enum AVOptionType type = TYPE_BASE(o->type);
    423    int ret = 0;
    424 
    425    if (type == AV_OPT_TYPE_RATIONAL || type == AV_OPT_TYPE_VIDEO_RATE) {
    426        int num, den;
    427        char c;
    428        if (sscanf(val, "%d%*1[:/]%d%c", &num, &den, &c) == 2) {
    429            if ((ret = write_number(obj, o, dst, 1, den, num)) >= 0)
    430                return ret;
    431            ret = 0;
    432        }
    433    }
    434 
    435    for (;;) {
    436        int i = 0;
    437        char buf[256];
    438        int cmd = 0;
    439        double d;
    440        int64_t intnum = 1;
    441 
    442        if (type == AV_OPT_TYPE_FLAGS) {
    443            if (*val == '+' || *val == '-')
    444                cmd = *(val++);
    445            for (; i < sizeof(buf) - 1 && val[i] && val[i] != '+' && val[i] != '-'; i++)
    446                buf[i] = val[i];
    447            buf[i] = 0;
    448        }
    449 
    450        {
    451            int res;
    452            int ci = 0;
    453            double const_values[64];
    454            const char * const_names[64];
    455            int search_flags = (o->flags & AV_OPT_FLAG_CHILD_CONSTS) ? AV_OPT_SEARCH_CHILDREN : 0;
    456            const AVOption *o_named = av_opt_find(target_obj, i ? buf : val, o->unit, 0, search_flags);
    457            if (o_named && o_named->type == AV_OPT_TYPE_CONST) {
    458                d = DEFAULT_NUMVAL(o_named);
    459                if (o_named->flags & AV_OPT_FLAG_DEPRECATED)
    460                    av_log(obj, AV_LOG_WARNING, "The \"%s\" option is deprecated: %s\n",
    461                           o_named->name, o_named->help);
    462            } else {
    463                if (o->unit) {
    464                    for (o_named = NULL; o_named = av_opt_next(target_obj, o_named); ) {
    465                        if (o_named->type == AV_OPT_TYPE_CONST &&
    466                            o_named->unit &&
    467                            !strcmp(o_named->unit, o->unit)) {
    468                            if (ci + 6 >= FF_ARRAY_ELEMS(const_values)) {
    469                                av_log(obj, AV_LOG_ERROR, "const_values array too small for %s\n", o->unit);
    470                                return AVERROR_PATCHWELCOME;
    471                            }
    472                            const_names [ci  ] = o_named->name;
    473                            const_values[ci++] = DEFAULT_NUMVAL(o_named);
    474                        }
    475                    }
    476                }
    477                const_names [ci  ] = "default";
    478                const_values[ci++] = DEFAULT_NUMVAL(o);
    479                const_names [ci  ] = "max";
    480                const_values[ci++] = o->max;
    481                const_names [ci  ] = "min";
    482                const_values[ci++] = o->min;
    483                const_names [ci  ] = "none";
    484                const_values[ci++] = 0;
    485                const_names [ci  ] = "all";
    486                const_values[ci++] = ~0;
    487                const_names [ci] = NULL;
    488                const_values[ci] = 0;
    489 
    490                res = av_expr_parse_and_eval(&d, i ? buf : val, const_names,
    491                                            const_values, NULL, NULL, NULL, NULL, NULL, 0, obj);
    492                if (res < 0) {
    493                    av_log(obj, AV_LOG_ERROR, "Unable to parse option value \"%s\"\n", val);
    494                    return res;
    495                }
    496            }
    497        }
    498        if (type == AV_OPT_TYPE_FLAGS) {
    499            intnum = *(unsigned int*)dst;
    500            if (cmd == '+')
    501                d = intnum | (int64_t)d;
    502            else if (cmd == '-')
    503                d = intnum &~(int64_t)d;
    504        }
    505 
    506        if ((ret = write_number(obj, o, dst, d, 1, 1)) < 0)
    507            return ret;
    508        val += i;
    509        if (!i || !*val)
    510            return 0;
    511    }
    512 }
    513 
    514 static int set_string_image_size(void *obj, const AVOption *o, const char *val, int *dst)
    515 {
    516    int ret;
    517 
    518    if (!val || !strcmp(val, "none")) {
    519        dst[0] =
    520        dst[1] = 0;
    521        return 0;
    522    }
    523    ret = av_parse_video_size(dst, dst + 1, val);
    524    if (ret < 0)
    525        av_log(obj, AV_LOG_ERROR, "Unable to parse option value \"%s\" as image size\n", val);
    526    return ret;
    527 }
    528 
    529 static int set_string_video_rate(void *obj, const AVOption *o, const char *val, AVRational *dst)
    530 {
    531    int ret = av_parse_video_rate(dst, val);
    532    if (ret < 0)
    533        av_log(obj, AV_LOG_ERROR, "Unable to parse option value \"%s\" as video rate\n", val);
    534    return ret;
    535 }
    536 
    537 static int set_string_color(void *obj, const AVOption *o, const char *val, uint8_t *dst)
    538 {
    539    int ret;
    540 
    541    if (!val) {
    542        return 0;
    543    } else {
    544        ret = av_parse_color(dst, val, -1, obj);
    545        if (ret < 0)
    546            av_log(obj, AV_LOG_ERROR, "Unable to parse option value \"%s\" as color\n", val);
    547        return ret;
    548    }
    549    return 0;
    550 }
    551 
    552 static const char *get_bool_name(int val)
    553 {
    554    if (val < 0)
    555        return "auto";
    556    return val ? "true" : "false";
    557 }
    558 
    559 static int set_string_bool(void *obj, const AVOption *o, const char *val, int *dst)
    560 {
    561    int n;
    562 
    563    if (!val)
    564        return 0;
    565 
    566    if (!strcmp(val, "auto")) {
    567        n = -1;
    568    } else if (av_match_name(val, "true,y,yes,enable,enabled,on")) {
    569        n = 1;
    570    } else if (av_match_name(val, "false,n,no,disable,disabled,off")) {
    571        n = 0;
    572    } else {
    573        char *end = NULL;
    574        n = strtol(val, &end, 10);
    575        if (val + strlen(val) != end)
    576            goto fail;
    577    }
    578 
    579    if (n < o->min || n > o->max)
    580        goto fail;
    581 
    582    *dst = n;
    583    return 0;
    584 
    585 fail:
    586    av_log(obj, AV_LOG_ERROR, "Unable to parse option value \"%s\" as boolean\n", val);
    587    return AVERROR(EINVAL);
    588 }
    589 
    590 static int set_string_fmt(void *obj, const AVOption *o, const char *val, uint8_t *dst,
    591                          int fmt_nb, int ((*get_fmt)(const char *)), const char *desc)
    592 {
    593    int fmt, min, max;
    594 
    595    if (!val || !strcmp(val, "none")) {
    596        fmt = -1;
    597    } else {
    598        fmt = get_fmt(val);
    599        if (fmt == -1) {
    600            char *tail;
    601            fmt = strtol(val, &tail, 0);
    602            if (*tail || (unsigned)fmt >= fmt_nb) {
    603                av_log(obj, AV_LOG_ERROR,
    604                       "Unable to parse option value \"%s\" as %s\n", val, desc);
    605                return AVERROR(EINVAL);
    606            }
    607        }
    608    }
    609 
    610    min = FFMAX(o->min, -1);
    611    max = FFMIN(o->max, fmt_nb-1);
    612 
    613    // hack for compatibility with old ffmpeg
    614    if(min == 0 && max == 0) {
    615        min = -1;
    616        max = fmt_nb-1;
    617    }
    618 
    619    if (fmt < min || fmt > max) {
    620        av_log(obj, AV_LOG_ERROR,
    621               "Value %d for parameter '%s' out of %s format range [%d - %d]\n",
    622               fmt, o->name, desc, min, max);
    623        return AVERROR(ERANGE);
    624    }
    625 
    626    *(int *)dst = fmt;
    627    return 0;
    628 }
    629 
    630 static int get_pix_fmt(const char *name)
    631 {
    632    return av_get_pix_fmt(name);
    633 }
    634 
    635 static int set_string_pixel_fmt(void *obj, const AVOption *o, const char *val, uint8_t *dst)
    636 {
    637    return set_string_fmt(obj, o, val, dst,
    638                          AV_PIX_FMT_NB, get_pix_fmt, "pixel format");
    639 }
    640 
    641 static int get_sample_fmt(const char *name)
    642 {
    643    return av_get_sample_fmt(name);
    644 }
    645 
    646 static int set_string_sample_fmt(void *obj, const AVOption *o, const char *val, uint8_t *dst)
    647 {
    648    return set_string_fmt(obj, o, val, dst,
    649                          AV_SAMPLE_FMT_NB, get_sample_fmt, "sample format");
    650 }
    651 
    652 static int set_string_dict(void *obj, const AVOption *o, const char *val, uint8_t **dst)
    653 {
    654    AVDictionary *options = NULL;
    655 
    656    if (val) {
    657        int ret = av_dict_parse_string(&options, val, "=", ":", 0);
    658        if (ret < 0) {
    659            av_dict_free(&options);
    660            return ret;
    661        }
    662    }
    663 
    664    av_dict_free((AVDictionary **)dst);
    665    *dst = (uint8_t *)options;
    666 
    667    return 0;
    668 }
    669 
    670 static int set_string_channel_layout(void *obj, const AVOption *o,
    671                                     const char *val, void *dst)
    672 {
    673    AVChannelLayout *channel_layout = dst;
    674    av_channel_layout_uninit(channel_layout);
    675    if (!val)
    676        return 0;
    677    return av_channel_layout_from_string(channel_layout, val);
    678 }
    679 
    680 static int opt_set_elem(void *obj, void *target_obj, const AVOption *o,
    681                        const char *val, void *dst)
    682 {
    683    const enum AVOptionType type = TYPE_BASE(o->type);
    684    int ret;
    685 
    686    if (!val && (type != AV_OPT_TYPE_STRING &&
    687                 type != AV_OPT_TYPE_PIXEL_FMT && type != AV_OPT_TYPE_SAMPLE_FMT &&
    688                 type != AV_OPT_TYPE_IMAGE_SIZE &&
    689                 type != AV_OPT_TYPE_DURATION && type != AV_OPT_TYPE_COLOR &&
    690                 type != AV_OPT_TYPE_BOOL))
    691        return AVERROR(EINVAL);
    692 
    693    switch (type) {
    694    case AV_OPT_TYPE_BOOL:
    695        return set_string_bool(obj, o, val, dst);
    696    case AV_OPT_TYPE_STRING:
    697        return set_string(obj, o, val, dst);
    698    case AV_OPT_TYPE_BINARY:
    699        return set_string_binary(obj, o, val, dst);
    700    case AV_OPT_TYPE_FLAGS:
    701    case AV_OPT_TYPE_INT:
    702    case AV_OPT_TYPE_UINT:
    703    case AV_OPT_TYPE_INT64:
    704    case AV_OPT_TYPE_UINT64:
    705    case AV_OPT_TYPE_FLOAT:
    706    case AV_OPT_TYPE_DOUBLE:
    707    case AV_OPT_TYPE_RATIONAL:
    708        return set_string_number(obj, target_obj, o, val, dst);
    709    case AV_OPT_TYPE_IMAGE_SIZE:
    710        return set_string_image_size(obj, o, val, dst);
    711    case AV_OPT_TYPE_VIDEO_RATE: {
    712        AVRational tmp;
    713        ret = set_string_video_rate(obj, o, val, &tmp);
    714        if (ret < 0)
    715            return ret;
    716        return write_number(obj, o, dst, 1, tmp.den, tmp.num);
    717    }
    718    case AV_OPT_TYPE_PIXEL_FMT:
    719        return set_string_pixel_fmt(obj, o, val, dst);
    720    case AV_OPT_TYPE_SAMPLE_FMT:
    721        return set_string_sample_fmt(obj, o, val, dst);
    722    case AV_OPT_TYPE_DURATION:
    723        {
    724            int64_t usecs = 0;
    725            if (val) {
    726                if ((ret = av_parse_time(&usecs, val, 1)) < 0) {
    727                    av_log(obj, AV_LOG_ERROR, "Unable to parse option value \"%s\" as duration\n", val);
    728                    return ret;
    729                }
    730            }
    731            if (usecs < o->min || usecs > o->max) {
    732                av_log(obj, AV_LOG_ERROR, "Value %f for parameter '%s' out of range [%g - %g]\n",
    733                       usecs / 1000000.0, o->name, o->min / 1000000.0, o->max / 1000000.0);
    734                return AVERROR(ERANGE);
    735            }
    736            *(int64_t *)dst = usecs;
    737            return 0;
    738        }
    739    case AV_OPT_TYPE_COLOR:
    740        return set_string_color(obj, o, val, dst);
    741    case AV_OPT_TYPE_CHLAYOUT:
    742        ret = set_string_channel_layout(obj, o, val, dst);
    743        if (ret < 0) {
    744            av_log(obj, AV_LOG_ERROR, "Unable to parse option value \"%s\" as channel layout\n", val);
    745            ret = AVERROR(EINVAL);
    746        }
    747        return ret;
    748    case AV_OPT_TYPE_DICT:
    749        return set_string_dict(obj, o, val, dst);
    750    }
    751 
    752    av_log(obj, AV_LOG_ERROR, "Invalid option type.\n");
    753    return AVERROR(EINVAL);
    754 }
    755 
    756 static int opt_set_array(void *obj, void *target_obj, const AVOption *o,
    757                         const char *val, void *dst)
    758 {
    759    const AVOptionArrayDef *arr = o->default_val.arr;
    760    const size_t      elem_size = opt_type_desc[TYPE_BASE(o->type)].size;
    761    const uint8_t           sep = opt_array_sep(o);
    762    uint8_t                *str = NULL;
    763 
    764    void       *elems = NULL;
    765    unsigned nb_elems = 0;
    766    int ret;
    767 
    768    if (val && *val) {
    769        str = av_malloc(strlen(val) + 1);
    770        if (!str)
    771            return AVERROR(ENOMEM);
    772    }
    773 
    774    // split and unescape the string
    775    while (val && *val) {
    776        uint8_t *p = str;
    777        void *tmp;
    778 
    779        if (arr && arr->size_max && nb_elems >= arr->size_max) {
    780            av_log(obj, AV_LOG_ERROR,
    781                   "Cannot assign more than %u elements to array option %s\n",
    782                   arr->size_max, o->name);
    783            ret = AVERROR(EINVAL);
    784            goto fail;
    785        }
    786 
    787        for (; *val; val++, p++) {
    788            if (*val == '\\' && val[1])
    789                val++;
    790            else if (*val == sep) {
    791                val++;
    792                break;
    793            }
    794            *p = *val;
    795        }
    796        *p = 0;
    797 
    798        tmp = av_realloc_array(elems, nb_elems + 1, elem_size);
    799        if (!tmp) {
    800            ret = AVERROR(ENOMEM);
    801            goto fail;
    802        }
    803        elems = tmp;
    804 
    805        tmp = opt_array_pelem(o, elems, nb_elems);
    806        memset(tmp, 0, elem_size);
    807 
    808        ret = opt_set_elem(obj, target_obj, o, str, tmp);
    809        if (ret < 0)
    810            goto fail;
    811        nb_elems++;
    812    }
    813    av_freep(&str);
    814 
    815    opt_free_array(o, dst, opt_array_pcount(dst));
    816 
    817    if (arr && nb_elems < arr->size_min) {
    818        av_log(obj, AV_LOG_ERROR,
    819               "Cannot assign fewer than %u elements to array option %s\n",
    820               arr->size_min, o->name);
    821        ret = AVERROR(EINVAL);
    822        goto fail;
    823    }
    824 
    825    *((void **)dst)        = elems;
    826    *opt_array_pcount(dst) = nb_elems;
    827 
    828    return 0;
    829 fail:
    830    av_freep(&str);
    831    opt_free_array(o, &elems, &nb_elems);
    832    return ret;
    833 }
    834 
    835 int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
    836 {
    837    void *dst, *target_obj;
    838    const AVOption *o;
    839    int ret;
    840 
    841    ret = opt_set_init(obj, name, search_flags, 0, &target_obj, &o, &dst);
    842    if (ret < 0)
    843        return ret;
    844 
    845    return ((o->type & AV_OPT_TYPE_FLAG_ARRAY) ?
    846            opt_set_array : opt_set_elem)(obj, target_obj, o, val, dst);
    847 }
    848 
    849 #define OPT_EVAL_NUMBER(name, opttype, vartype)                         \
    850 int av_opt_eval_ ## name(void *obj, const AVOption *o,                  \
    851                         const char *val, vartype *name ## _out)        \
    852 {                                                                       \
    853    if (!o || o->type != opttype || o->flags & AV_OPT_FLAG_READONLY)    \
    854        return AVERROR(EINVAL);                                         \
    855    return set_string_number(obj, obj, o, val, name ## _out);           \
    856 }
    857 
    858 OPT_EVAL_NUMBER(flags,  AV_OPT_TYPE_FLAGS,    int)
    859 OPT_EVAL_NUMBER(int,    AV_OPT_TYPE_INT,      int)
    860 OPT_EVAL_NUMBER(uint,   AV_OPT_TYPE_UINT,     unsigned)
    861 OPT_EVAL_NUMBER(int64,  AV_OPT_TYPE_INT64,    int64_t)
    862 OPT_EVAL_NUMBER(float,  AV_OPT_TYPE_FLOAT,    float)
    863 OPT_EVAL_NUMBER(double, AV_OPT_TYPE_DOUBLE,   double)
    864 OPT_EVAL_NUMBER(q,      AV_OPT_TYPE_RATIONAL, AVRational)
    865 
    866 static int set_number(void *obj, const char *name, double num, int den, int64_t intnum,
    867                      int search_flags, int require_type)
    868 {
    869    void *dst;
    870    const AVOption *o;
    871    int ret;
    872 
    873    ret = opt_set_init(obj, name, search_flags, require_type, NULL, &o, &dst);
    874    if (ret < 0)
    875        return ret;
    876 
    877    return write_number(obj, o, dst, num, den, intnum);
    878 }
    879 
    880 int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
    881 {
    882    return set_number(obj, name, 1, 1, val, search_flags, 0);
    883 }
    884 
    885 int av_opt_set_double(void *obj, const char *name, double val, int search_flags)
    886 {
    887    return set_number(obj, name, val, 1, 1, search_flags, 0);
    888 }
    889 
    890 int av_opt_set_q(void *obj, const char *name, AVRational val, int search_flags)
    891 {
    892    return set_number(obj, name, val.num, val.den, 1, search_flags, 0);
    893 }
    894 
    895 int av_opt_set_bin(void *obj, const char *name, const uint8_t *val, int len, int search_flags)
    896 {
    897    uint8_t *ptr;
    898    uint8_t **dst;
    899    int *lendst;
    900    int ret;
    901 
    902    ret = opt_set_init(obj, name, search_flags, AV_OPT_TYPE_BINARY,
    903                       NULL, NULL, (void**)&dst);
    904    if (ret < 0)
    905        return ret;
    906 
    907    ptr = len ? av_malloc(len) : NULL;
    908    if (len && !ptr)
    909        return AVERROR(ENOMEM);
    910 
    911    lendst = (int *)(dst + 1);
    912 
    913    av_free(*dst);
    914    *dst    = ptr;
    915    *lendst = len;
    916    if (len)
    917        memcpy(ptr, val, len);
    918 
    919    return 0;
    920 }
    921 
    922 int av_opt_set_image_size(void *obj, const char *name, int w, int h, int search_flags)
    923 {
    924    const AVOption *o;
    925    int *dst;
    926    int ret;
    927 
    928    ret = opt_set_init(obj, name, search_flags, AV_OPT_TYPE_IMAGE_SIZE,
    929                       NULL, &o, (void**)&dst);
    930    if (ret < 0)
    931        return ret;
    932 
    933    if (w<0 || h<0) {
    934        av_log(obj, AV_LOG_ERROR,
    935               "Invalid negative size value %dx%d for size '%s'\n", w, h, o->name);
    936        return AVERROR(EINVAL);
    937    }
    938 
    939    dst[0] = w;
    940    dst[1] = h;
    941 
    942    return 0;
    943 }
    944 
    945 int av_opt_set_video_rate(void *obj, const char *name, AVRational val, int search_flags)
    946 {
    947    return set_number(obj, name, val.num, val.den, 1, search_flags, AV_OPT_TYPE_VIDEO_RATE);
    948 }
    949 
    950 static int set_format(void *obj, const char *name, int fmt, int search_flags,
    951                      enum AVOptionType type, const char *desc, int nb_fmts)
    952 {
    953    const AVOption *o;
    954    int *dst;
    955    int min, max, ret;
    956 
    957    ret = opt_set_init(obj, name, search_flags, type, NULL, &o, (void**)&dst);
    958    if (ret < 0)
    959        return ret;
    960 
    961    min = FFMAX(o->min, -1);
    962    max = FFMIN(o->max, nb_fmts-1);
    963 
    964    if (fmt < min || fmt > max) {
    965        av_log(obj, AV_LOG_ERROR,
    966               "Value %d for parameter '%s' out of %s format range [%d - %d]\n",
    967               fmt, name, desc, min, max);
    968        return AVERROR(ERANGE);
    969    }
    970    *dst = fmt;
    971    return 0;
    972 }
    973 
    974 int av_opt_set_pixel_fmt(void *obj, const char *name, enum AVPixelFormat fmt, int search_flags)
    975 {
    976    return set_format(obj, name, fmt, search_flags, AV_OPT_TYPE_PIXEL_FMT, "pixel", AV_PIX_FMT_NB);
    977 }
    978 
    979 int av_opt_set_sample_fmt(void *obj, const char *name, enum AVSampleFormat fmt, int search_flags)
    980 {
    981    return set_format(obj, name, fmt, search_flags, AV_OPT_TYPE_SAMPLE_FMT, "sample", AV_SAMPLE_FMT_NB);
    982 }
    983 
    984 int av_opt_set_dict_val(void *obj, const char *name, const AVDictionary *val,
    985                        int search_flags)
    986 {
    987    AVDictionary **dst;
    988    int ret;
    989 
    990    ret = opt_set_init(obj, name, search_flags, AV_OPT_TYPE_DICT, NULL, NULL,
    991                       (void**)&dst);
    992    if (ret < 0)
    993        return ret;
    994 
    995    av_dict_free(dst);
    996 
    997    return av_dict_copy(dst, val, 0);
    998 }
    999 
   1000 int av_opt_set_chlayout(void *obj, const char *name,
   1001                        const AVChannelLayout *channel_layout,
   1002                        int search_flags)
   1003 {
   1004    AVChannelLayout *dst;
   1005    int ret;
   1006 
   1007    ret = opt_set_init(obj, name, search_flags, AV_OPT_TYPE_CHLAYOUT, NULL, NULL,
   1008                       (void**)&dst);
   1009    if (ret < 0)
   1010        return ret;
   1011 
   1012    return av_channel_layout_copy(dst, channel_layout);
   1013 }
   1014 
   1015 static void format_duration(char *buf, size_t size, int64_t d)
   1016 {
   1017    char *e;
   1018 
   1019    av_assert0(size >= 25);
   1020    if (d < 0 && d != INT64_MIN) {
   1021        *(buf++) = '-';
   1022        size--;
   1023        d = -d;
   1024    }
   1025    if (d == INT64_MAX)
   1026        snprintf(buf, size, "INT64_MAX");
   1027    else if (d == INT64_MIN)
   1028        snprintf(buf, size, "INT64_MIN");
   1029    else if (d > (int64_t)3600*1000000)
   1030        snprintf(buf, size, "%"PRId64":%02d:%02d.%06d", d / 3600000000,
   1031                 (int)((d / 60000000) % 60),
   1032                 (int)((d / 1000000) % 60),
   1033                 (int)(d % 1000000));
   1034    else if (d > 60*1000000)
   1035        snprintf(buf, size, "%d:%02d.%06d",
   1036                 (int)(d / 60000000),
   1037                 (int)((d / 1000000) % 60),
   1038                 (int)(d % 1000000));
   1039    else
   1040        snprintf(buf, size, "%d.%06d",
   1041                 (int)(d / 1000000),
   1042                 (int)(d % 1000000));
   1043    e = buf + strlen(buf);
   1044    while (e > buf && e[-1] == '0')
   1045        *(--e) = 0;
   1046    if (e > buf && e[-1] == '.')
   1047        *(--e) = 0;
   1048 }
   1049 
   1050 static int opt_get_elem(const AVOption *o, uint8_t **pbuf, size_t buf_len,
   1051                        const void *dst, int search_flags)
   1052 {
   1053    int ret;
   1054 
   1055    switch (TYPE_BASE(o->type)) {
   1056    case AV_OPT_TYPE_BOOL:
   1057        ret = snprintf(*pbuf, buf_len, "%s", get_bool_name(*(int *)dst));
   1058        break;
   1059    case AV_OPT_TYPE_FLAGS:
   1060        ret = snprintf(*pbuf, buf_len, "0x%08X", *(int *)dst);
   1061        break;
   1062    case AV_OPT_TYPE_INT:
   1063        ret = snprintf(*pbuf, buf_len, "%d", *(int *)dst);
   1064        break;
   1065    case AV_OPT_TYPE_UINT:
   1066        ret = snprintf(*pbuf, buf_len, "%u", *(unsigned *)dst);
   1067        break;
   1068    case AV_OPT_TYPE_INT64:
   1069        ret = snprintf(*pbuf, buf_len, "%"PRId64, *(int64_t *)dst);
   1070        break;
   1071    case AV_OPT_TYPE_UINT64:
   1072        ret = snprintf(*pbuf, buf_len, "%"PRIu64, *(uint64_t *)dst);
   1073        break;
   1074    case AV_OPT_TYPE_FLOAT:
   1075        ret = snprintf(*pbuf, buf_len, "%f", *(float *)dst);
   1076        break;
   1077    case AV_OPT_TYPE_DOUBLE:
   1078        ret = snprintf(*pbuf, buf_len, "%f", *(double *)dst);
   1079        break;
   1080    case AV_OPT_TYPE_VIDEO_RATE:
   1081    case AV_OPT_TYPE_RATIONAL:
   1082        ret = snprintf(*pbuf, buf_len, "%d/%d", ((AVRational *)dst)->num, ((AVRational *)dst)->den);
   1083        break;
   1084    case AV_OPT_TYPE_CONST:
   1085        ret = snprintf(*pbuf, buf_len, "%"PRId64, o->default_val.i64);
   1086        break;
   1087    case AV_OPT_TYPE_STRING:
   1088        if (*(uint8_t **)dst) {
   1089            *pbuf = av_strdup(*(uint8_t **)dst);
   1090        } else if (search_flags & AV_OPT_ALLOW_NULL) {
   1091            *pbuf = NULL;
   1092            return 0;
   1093        } else {
   1094            *pbuf = av_strdup("");
   1095        }
   1096        return *pbuf ? 0 : AVERROR(ENOMEM);
   1097    case AV_OPT_TYPE_BINARY: {
   1098        const uint8_t *bin;
   1099        int len;
   1100 
   1101        if (!*(uint8_t **)dst && (search_flags & AV_OPT_ALLOW_NULL)) {
   1102            *pbuf = NULL;
   1103            return 0;
   1104        }
   1105        len = *(int *)(((uint8_t *)dst) + sizeof(uint8_t *));
   1106        if ((uint64_t)len * 2 + 1 > INT_MAX)
   1107            return AVERROR(EINVAL);
   1108        if (!(*pbuf = av_malloc(len * 2 + 1)))
   1109            return AVERROR(ENOMEM);
   1110        if (!len) {
   1111            *pbuf[0] = '\0';
   1112            return 0;
   1113        }
   1114        bin = *(uint8_t **)dst;
   1115        for (int i = 0; i < len; i++)
   1116            snprintf(*pbuf + i * 2, 3, "%02X", bin[i]);
   1117        return 0;
   1118    }
   1119    case AV_OPT_TYPE_IMAGE_SIZE:
   1120        ret = snprintf(*pbuf, buf_len, "%dx%d", ((int *)dst)[0], ((int *)dst)[1]);
   1121        break;
   1122    case AV_OPT_TYPE_PIXEL_FMT:
   1123        ret = snprintf(*pbuf, buf_len, "%s", (char *)av_x_if_null(av_get_pix_fmt_name(*(enum AVPixelFormat *)dst), "none"));
   1124        break;
   1125    case AV_OPT_TYPE_SAMPLE_FMT:
   1126        ret = snprintf(*pbuf, buf_len, "%s", (char *)av_x_if_null(av_get_sample_fmt_name(*(enum AVSampleFormat *)dst), "none"));
   1127        break;
   1128    case AV_OPT_TYPE_DURATION: {
   1129        int64_t i64 = *(int64_t *)dst;
   1130        format_duration(*pbuf, buf_len, i64);
   1131        ret = strlen(*pbuf); // no overflow possible, checked by an assert
   1132        break;
   1133    }
   1134    case AV_OPT_TYPE_COLOR:
   1135        ret = snprintf(*pbuf, buf_len, "0x%02x%02x%02x%02x",
   1136                       (int)((uint8_t *)dst)[0], (int)((uint8_t *)dst)[1],
   1137                       (int)((uint8_t *)dst)[2], (int)((uint8_t *)dst)[3]);
   1138        break;
   1139    case AV_OPT_TYPE_CHLAYOUT:
   1140        ret = av_channel_layout_describe(dst, *pbuf, buf_len);
   1141        break;
   1142    case AV_OPT_TYPE_DICT:
   1143        if (!*(AVDictionary **)dst && (search_flags & AV_OPT_ALLOW_NULL)) {
   1144            *pbuf = NULL;
   1145            return 0;
   1146        }
   1147        return av_dict_get_string(*(AVDictionary **)dst, (char **)pbuf, '=', ':');
   1148    default:
   1149        return AVERROR(EINVAL);
   1150    }
   1151 
   1152    return ret;
   1153 }
   1154 
   1155 static int opt_get_array(const AVOption *o, void *dst, uint8_t **out_val)
   1156 {
   1157    const unsigned count = *opt_array_pcount(dst);
   1158    const uint8_t    sep = opt_array_sep(o);
   1159 
   1160    uint8_t *str     = NULL;
   1161    size_t   str_len = 0;
   1162    int ret;
   1163 
   1164    *out_val = NULL;
   1165 
   1166    for (unsigned i = 0; i < count; i++) {
   1167        uint8_t buf[128], *out = buf;
   1168        size_t out_len;
   1169 
   1170        ret = opt_get_elem(o, &out, sizeof(buf),
   1171                           opt_array_pelem(o, *(void **)dst, i), 0);
   1172        if (ret < 0)
   1173            goto fail;
   1174 
   1175        out_len = strlen(out);
   1176        if (out_len > SIZE_MAX / 2 - !!i ||
   1177            !!i + out_len * 2 > SIZE_MAX - str_len - 1) {
   1178            ret = AVERROR(ERANGE);
   1179            goto fail;
   1180        }
   1181 
   1182        //                         terminator     escaping  separator
   1183        //                                ↓             ↓     ↓
   1184        ret = av_reallocp(&str, str_len + 1 + out_len * 2 + !!i);
   1185        if (ret < 0)
   1186            goto fail;
   1187 
   1188        // add separator if needed
   1189        if (i)
   1190            str[str_len++] = sep;
   1191 
   1192        // escape the element
   1193        for (unsigned j = 0; j < out_len; j++) {
   1194            uint8_t val = out[j];
   1195            if (val == sep || val == '\\')
   1196                str[str_len++] = '\\';
   1197            str[str_len++] = val;
   1198        }
   1199        str[str_len] = 0;
   1200 
   1201 fail:
   1202        if (out != buf)
   1203            av_freep(&out);
   1204        if (ret < 0) {
   1205            av_freep(&str);
   1206            return ret;
   1207        }
   1208    }
   1209 
   1210    *out_val = str;
   1211 
   1212    return 0;
   1213 }
   1214 
   1215 int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
   1216 {
   1217    void *dst, *target_obj;
   1218    const AVOption *o = av_opt_find2(obj, name, NULL, 0, search_flags, &target_obj);
   1219    uint8_t *out, buf[128];
   1220    int ret;
   1221 
   1222    if (!o || !target_obj || (o->offset<=0 && o->type != AV_OPT_TYPE_CONST))
   1223        return AVERROR_OPTION_NOT_FOUND;
   1224 
   1225    if (o->flags & AV_OPT_FLAG_DEPRECATED)
   1226        av_log(obj, AV_LOG_WARNING, "The \"%s\" option is deprecated: %s\n", name, o->help);
   1227 
   1228    dst = (uint8_t *)target_obj + o->offset;
   1229 
   1230    if (o->type & AV_OPT_TYPE_FLAG_ARRAY) {
   1231        ret = opt_get_array(o, dst, out_val);
   1232        if (ret < 0)
   1233            return ret;
   1234        if (!*out_val && !(search_flags & AV_OPT_ALLOW_NULL)) {
   1235            *out_val = av_strdup("");
   1236            if (!*out_val)
   1237               return AVERROR(ENOMEM);
   1238        }
   1239        return 0;
   1240    }
   1241 
   1242    buf[0] = 0;
   1243    out = buf;
   1244    ret = opt_get_elem(o, &out, sizeof(buf), dst, search_flags);
   1245    if (ret < 0)
   1246        return ret;
   1247    if (out != buf) {
   1248        *out_val = out;
   1249        return 0;
   1250    }
   1251 
   1252    if (ret >= sizeof(buf))
   1253        return AVERROR(EINVAL);
   1254    *out_val = av_strdup(out);
   1255    return *out_val ? 0 : AVERROR(ENOMEM);
   1256 }
   1257 
   1258 static int get_number(void *obj, const char *name, double *num, int *den, int64_t *intnum,
   1259                      int search_flags)
   1260 {
   1261    void *dst, *target_obj;
   1262    const AVOption *o = av_opt_find2(obj, name, NULL, 0, search_flags, &target_obj);
   1263    if (!o || !target_obj)
   1264        return AVERROR_OPTION_NOT_FOUND;
   1265    if (o->type & AV_OPT_TYPE_FLAG_ARRAY)
   1266        return AVERROR(EINVAL);
   1267 
   1268    dst = ((uint8_t *)target_obj) + o->offset;
   1269 
   1270    return read_number(o, dst, num, den, intnum);
   1271 }
   1272 
   1273 int av_opt_get_int(void *obj, const char *name, int search_flags, int64_t *out_val)
   1274 {
   1275    int64_t intnum = 1;
   1276    double num = 1;
   1277    int ret, den = 1;
   1278 
   1279    if ((ret = get_number(obj, name, &num, &den, &intnum, search_flags)) < 0)
   1280        return ret;
   1281    if (num == den)
   1282        *out_val = intnum;
   1283    else
   1284        *out_val = num * intnum / den;
   1285    return 0;
   1286 }
   1287 
   1288 int av_opt_get_double(void *obj, const char *name, int search_flags, double *out_val)
   1289 {
   1290    int64_t intnum = 1;
   1291    double num = 1;
   1292    int ret, den = 1;
   1293 
   1294    if ((ret = get_number(obj, name, &num, &den, &intnum, search_flags)) < 0)
   1295        return ret;
   1296    *out_val = num * intnum / den;
   1297    return 0;
   1298 }
   1299 
   1300 int av_opt_get_q(void *obj, const char *name, int search_flags, AVRational *out_val)
   1301 {
   1302    int64_t intnum = 1;
   1303    double num = 1;
   1304    int ret, den = 1;
   1305 
   1306    if ((ret = get_number(obj, name, &num, &den, &intnum, search_flags)) < 0)
   1307        return ret;
   1308 
   1309    if (num == 1.0 && (int)intnum == intnum)
   1310        *out_val = (AVRational){intnum, den};
   1311    else
   1312        *out_val = double_to_rational(num*intnum/den);
   1313    return 0;
   1314 }
   1315 
   1316 int av_opt_get_image_size(void *obj, const char *name, int search_flags, int *w_out, int *h_out)
   1317 {
   1318    void *dst, *target_obj;
   1319    const AVOption *o = av_opt_find2(obj, name, NULL, 0, search_flags, &target_obj);
   1320    if (!o || !target_obj)
   1321        return AVERROR_OPTION_NOT_FOUND;
   1322    if (o->type != AV_OPT_TYPE_IMAGE_SIZE) {
   1323        av_log(obj, AV_LOG_ERROR,
   1324               "The value for option '%s' is not a image size.\n", name);
   1325        return AVERROR(EINVAL);
   1326    }
   1327 
   1328    dst = ((uint8_t*)target_obj) + o->offset;
   1329    if (w_out) *w_out = *(int *)dst;
   1330    if (h_out) *h_out = *((int *)dst+1);
   1331    return 0;
   1332 }
   1333 
   1334 int av_opt_get_video_rate(void *obj, const char *name, int search_flags, AVRational *out_val)
   1335 {
   1336    return av_opt_get_q(obj, name, search_flags, out_val);
   1337 }
   1338 
   1339 static int get_format(void *obj, const char *name, int search_flags, int *out_fmt,
   1340                      enum AVOptionType type, const char *desc)
   1341 {
   1342    void *dst, *target_obj;
   1343    const AVOption *o = av_opt_find2(obj, name, NULL, 0, search_flags, &target_obj);
   1344    if (!o || !target_obj)
   1345        return AVERROR_OPTION_NOT_FOUND;
   1346    if (o->type != type) {
   1347        av_log(obj, AV_LOG_ERROR,
   1348               "The value for option '%s' is not a %s format.\n", desc, name);
   1349        return AVERROR(EINVAL);
   1350    }
   1351 
   1352    dst = ((uint8_t*)target_obj) + o->offset;
   1353    *out_fmt = *(int *)dst;
   1354    return 0;
   1355 }
   1356 
   1357 int av_opt_get_pixel_fmt(void *obj, const char *name, int search_flags, enum AVPixelFormat *out_fmt)
   1358 {
   1359    return get_format(obj, name, search_flags, out_fmt, AV_OPT_TYPE_PIXEL_FMT, "pixel");
   1360 }
   1361 
   1362 int av_opt_get_sample_fmt(void *obj, const char *name, int search_flags, enum AVSampleFormat *out_fmt)
   1363 {
   1364    return get_format(obj, name, search_flags, out_fmt, AV_OPT_TYPE_SAMPLE_FMT, "sample");
   1365 }
   1366 
   1367 int av_opt_get_chlayout(void *obj, const char *name, int search_flags, AVChannelLayout *cl)
   1368 {
   1369    void *dst, *target_obj;
   1370    const AVOption *o = av_opt_find2(obj, name, NULL, 0, search_flags, &target_obj);
   1371    if (!o || !target_obj)
   1372        return AVERROR_OPTION_NOT_FOUND;
   1373    if (o->type != AV_OPT_TYPE_CHLAYOUT) {
   1374        av_log(obj, AV_LOG_ERROR,
   1375               "The value for option '%s' is not a channel layout.\n", name);
   1376        return AVERROR(EINVAL);
   1377    }
   1378 
   1379    dst = ((uint8_t*)target_obj) + o->offset;
   1380    return av_channel_layout_copy(cl, dst);
   1381 }
   1382 
   1383 int av_opt_get_dict_val(void *obj, const char *name, int search_flags, AVDictionary **out_val)
   1384 {
   1385    void *target_obj;
   1386    AVDictionary *src;
   1387    const AVOption *o = av_opt_find2(obj, name, NULL, 0, search_flags, &target_obj);
   1388 
   1389    if (!o || !target_obj)
   1390        return AVERROR_OPTION_NOT_FOUND;
   1391    if (o->type != AV_OPT_TYPE_DICT)
   1392        return AVERROR(EINVAL);
   1393 
   1394    src = *(AVDictionary **)(((uint8_t *)target_obj) + o->offset);
   1395 
   1396    return av_dict_copy(out_val, src, 0);
   1397 }
   1398 
   1399 int av_opt_flag_is_set(void *obj, const char *field_name, const char *flag_name)
   1400 {
   1401    const AVOption *field = av_opt_find(obj, field_name, NULL, 0, 0);
   1402    const AVOption *flag  = av_opt_find(obj, flag_name,
   1403                                        field ? field->unit : NULL, 0, 0);
   1404    int64_t res;
   1405 
   1406    if (!field || !flag || flag->type != AV_OPT_TYPE_CONST ||
   1407        av_opt_get_int(obj, field_name, 0, &res) < 0)
   1408        return 0;
   1409    return res & flag->default_val.i64;
   1410 }
   1411 
   1412 static void log_int_value(void *av_log_obj, int level, int64_t i)
   1413 {
   1414    if (i == INT_MAX) {
   1415        av_log(av_log_obj, level, "INT_MAX");
   1416    } else if (i == INT_MIN) {
   1417        av_log(av_log_obj, level, "INT_MIN");
   1418    } else if (i == UINT32_MAX) {
   1419        av_log(av_log_obj, level, "UINT32_MAX");
   1420    } else if (i == INT64_MAX) {
   1421        av_log(av_log_obj, level, "I64_MAX");
   1422    } else if (i == INT64_MIN) {
   1423        av_log(av_log_obj, level, "I64_MIN");
   1424    } else {
   1425        av_log(av_log_obj, level, "%"PRId64, i);
   1426    }
   1427 }
   1428 
   1429 static void log_value(void *av_log_obj, int level, double d)
   1430 {
   1431    if      (d == INT_MAX) {
   1432        av_log(av_log_obj, level, "INT_MAX");
   1433    } else if (d == INT_MIN) {
   1434        av_log(av_log_obj, level, "INT_MIN");
   1435    } else if (d == UINT32_MAX) {
   1436        av_log(av_log_obj, level, "UINT32_MAX");
   1437    } else if (d == (double)INT64_MAX) {
   1438        av_log(av_log_obj, level, "I64_MAX");
   1439    } else if (d == INT64_MIN) {
   1440        av_log(av_log_obj, level, "I64_MIN");
   1441    } else if (d == FLT_MAX) {
   1442        av_log(av_log_obj, level, "FLT_MAX");
   1443    } else if (d == FLT_MIN) {
   1444        av_log(av_log_obj, level, "FLT_MIN");
   1445    } else if (d == -FLT_MAX) {
   1446        av_log(av_log_obj, level, "-FLT_MAX");
   1447    } else if (d == -FLT_MIN) {
   1448        av_log(av_log_obj, level, "-FLT_MIN");
   1449    } else if (d == DBL_MAX) {
   1450        av_log(av_log_obj, level, "DBL_MAX");
   1451    } else if (d == DBL_MIN) {
   1452        av_log(av_log_obj, level, "DBL_MIN");
   1453    } else if (d == -DBL_MAX) {
   1454        av_log(av_log_obj, level, "-DBL_MAX");
   1455    } else if (d == -DBL_MIN) {
   1456        av_log(av_log_obj, level, "-DBL_MIN");
   1457    } else {
   1458        av_log(av_log_obj, level, "%g", d);
   1459    }
   1460 }
   1461 
   1462 static const char *get_opt_const_name(void *obj, const char *unit, int64_t value)
   1463 {
   1464    const AVOption *opt = NULL;
   1465 
   1466    if (!unit)
   1467        return NULL;
   1468    while ((opt = av_opt_next(obj, opt)))
   1469        if (opt->type == AV_OPT_TYPE_CONST && !strcmp(opt->unit, unit) &&
   1470            opt->default_val.i64 == value)
   1471            return opt->name;
   1472    return NULL;
   1473 }
   1474 
   1475 static char *get_opt_flags_string(void *obj, const char *unit, int64_t value)
   1476 {
   1477    const AVOption *opt = NULL;
   1478    char flags[512];
   1479 
   1480    flags[0] = 0;
   1481    if (!unit)
   1482        return NULL;
   1483    while ((opt = av_opt_next(obj, opt))) {
   1484        if (opt->type == AV_OPT_TYPE_CONST && !strcmp(opt->unit, unit) &&
   1485            opt->default_val.i64 & value) {
   1486            if (flags[0])
   1487                av_strlcatf(flags, sizeof(flags), "+");
   1488            av_strlcatf(flags, sizeof(flags), "%s", opt->name);
   1489        }
   1490    }
   1491    if (flags[0])
   1492        return av_strdup(flags);
   1493    return NULL;
   1494 }
   1495 
   1496 static void log_type(void *av_log_obj, const AVOption *o,
   1497                     enum AVOptionType parent_type)
   1498 {
   1499    const enum AVOptionType type = TYPE_BASE(o->type);
   1500 
   1501    if (o->type == AV_OPT_TYPE_CONST && TYPE_BASE(parent_type) == AV_OPT_TYPE_INT)
   1502        av_log(av_log_obj, AV_LOG_INFO, "%-12"PRId64" ", o->default_val.i64);
   1503    else if (type < FF_ARRAY_ELEMS(opt_type_desc) && opt_type_desc[type].name) {
   1504        if (o->type & AV_OPT_TYPE_FLAG_ARRAY)
   1505            av_log(av_log_obj, AV_LOG_INFO, "[%-10s]", opt_type_desc[type].name);
   1506        else
   1507            av_log(av_log_obj, AV_LOG_INFO, "%-12s ", opt_type_desc[type].name);
   1508    }
   1509    else
   1510        av_log(av_log_obj, AV_LOG_INFO, "%-12s ", "");
   1511 }
   1512 
   1513 static void log_default(void *obj, void *av_log_obj, const AVOption *opt)
   1514 {
   1515    if (opt->type == AV_OPT_TYPE_CONST || opt->type == AV_OPT_TYPE_BINARY)
   1516        return;
   1517    if ((opt->type == AV_OPT_TYPE_COLOR      ||
   1518         opt->type == AV_OPT_TYPE_IMAGE_SIZE ||
   1519         opt->type == AV_OPT_TYPE_STRING     ||
   1520         opt->type == AV_OPT_TYPE_DICT       ||
   1521         opt->type == AV_OPT_TYPE_CHLAYOUT   ||
   1522         opt->type == AV_OPT_TYPE_VIDEO_RATE) &&
   1523        !opt->default_val.str)
   1524        return;
   1525 
   1526    if (opt->type & AV_OPT_TYPE_FLAG_ARRAY) {
   1527        const AVOptionArrayDef *arr = opt->default_val.arr;
   1528        if (arr && arr->def)
   1529            av_log(av_log_obj, AV_LOG_INFO, " (default %s)", arr->def);
   1530        return;
   1531    }
   1532 
   1533    av_log(av_log_obj, AV_LOG_INFO, " (default ");
   1534    switch (opt->type) {
   1535    case AV_OPT_TYPE_BOOL:
   1536        av_log(av_log_obj, AV_LOG_INFO, "%s", get_bool_name(opt->default_val.i64));
   1537        break;
   1538    case AV_OPT_TYPE_FLAGS: {
   1539        char *def_flags = get_opt_flags_string(obj, opt->unit, opt->default_val.i64);
   1540        if (def_flags) {
   1541            av_log(av_log_obj, AV_LOG_INFO, "%s", def_flags);
   1542            av_freep(&def_flags);
   1543        } else {
   1544            av_log(av_log_obj, AV_LOG_INFO, "%"PRIX64, opt->default_val.i64);
   1545        }
   1546        break;
   1547    }
   1548    case AV_OPT_TYPE_DURATION: {
   1549        char buf[25];
   1550        format_duration(buf, sizeof(buf), opt->default_val.i64);
   1551        av_log(av_log_obj, AV_LOG_INFO, "%s", buf);
   1552        break;
   1553    }
   1554    case AV_OPT_TYPE_UINT:
   1555    case AV_OPT_TYPE_INT:
   1556    case AV_OPT_TYPE_UINT64:
   1557    case AV_OPT_TYPE_INT64: {
   1558        const char *def_const = get_opt_const_name(obj, opt->unit, opt->default_val.i64);
   1559        if (def_const)
   1560            av_log(av_log_obj, AV_LOG_INFO, "%s", def_const);
   1561        else
   1562            log_int_value(av_log_obj, AV_LOG_INFO, opt->default_val.i64);
   1563        break;
   1564    }
   1565    case AV_OPT_TYPE_DOUBLE:
   1566    case AV_OPT_TYPE_FLOAT:
   1567        log_value(av_log_obj, AV_LOG_INFO, opt->default_val.dbl);
   1568        break;
   1569    case AV_OPT_TYPE_RATIONAL: {
   1570        AVRational q = av_d2q(opt->default_val.dbl, INT_MAX);
   1571        av_log(av_log_obj, AV_LOG_INFO, "%d/%d", q.num, q.den); }
   1572        break;
   1573    case AV_OPT_TYPE_PIXEL_FMT:
   1574        av_log(av_log_obj, AV_LOG_INFO, "%s", (char *)av_x_if_null(av_get_pix_fmt_name(opt->default_val.i64), "none"));
   1575        break;
   1576    case AV_OPT_TYPE_SAMPLE_FMT:
   1577        av_log(av_log_obj, AV_LOG_INFO, "%s", (char *)av_x_if_null(av_get_sample_fmt_name(opt->default_val.i64), "none"));
   1578        break;
   1579    case AV_OPT_TYPE_COLOR:
   1580    case AV_OPT_TYPE_IMAGE_SIZE:
   1581    case AV_OPT_TYPE_STRING:
   1582    case AV_OPT_TYPE_DICT:
   1583    case AV_OPT_TYPE_VIDEO_RATE:
   1584    case AV_OPT_TYPE_CHLAYOUT:
   1585        av_log(av_log_obj, AV_LOG_INFO, "\"%s\"", opt->default_val.str);
   1586        break;
   1587    }
   1588    av_log(av_log_obj, AV_LOG_INFO, ")");
   1589 }
   1590 
   1591 static void opt_list(void *obj, void *av_log_obj, const char *unit,
   1592                     int req_flags, int rej_flags, enum AVOptionType parent_type)
   1593 {
   1594    const AVOption *opt = NULL;
   1595    AVOptionRanges *r;
   1596    int i;
   1597 
   1598    while ((opt = av_opt_next(obj, opt))) {
   1599        if (!(opt->flags & req_flags) || (opt->flags & rej_flags))
   1600            continue;
   1601 
   1602        /* Don't print CONST's on level one.
   1603         * Don't print anything but CONST's on level two.
   1604         * Only print items from the requested unit.
   1605         */
   1606        if (!unit && opt->type == AV_OPT_TYPE_CONST)
   1607            continue;
   1608        else if (unit && opt->type != AV_OPT_TYPE_CONST)
   1609            continue;
   1610        else if (unit && opt->type == AV_OPT_TYPE_CONST && strcmp(unit, opt->unit))
   1611            continue;
   1612        else if (unit && opt->type == AV_OPT_TYPE_CONST)
   1613            av_log(av_log_obj, AV_LOG_INFO, "     %-15s ", opt->name);
   1614        else
   1615            av_log(av_log_obj, AV_LOG_INFO, "  %s%-17s ",
   1616                   (opt->flags & AV_OPT_FLAG_FILTERING_PARAM) ? " " : "-",
   1617                   opt->name);
   1618 
   1619        log_type(av_log_obj, opt, parent_type);
   1620 
   1621        av_log(av_log_obj, AV_LOG_INFO, "%c%c%c%c%c%c%c%c%c%c%c",
   1622               (opt->flags & AV_OPT_FLAG_ENCODING_PARAM)  ? 'E' : '.',
   1623               (opt->flags & AV_OPT_FLAG_DECODING_PARAM)  ? 'D' : '.',
   1624               (opt->flags & AV_OPT_FLAG_FILTERING_PARAM) ? 'F' : '.',
   1625               (opt->flags & AV_OPT_FLAG_VIDEO_PARAM)     ? 'V' : '.',
   1626               (opt->flags & AV_OPT_FLAG_AUDIO_PARAM)     ? 'A' : '.',
   1627               (opt->flags & AV_OPT_FLAG_SUBTITLE_PARAM)  ? 'S' : '.',
   1628               (opt->flags & AV_OPT_FLAG_EXPORT)          ? 'X' : '.',
   1629               (opt->flags & AV_OPT_FLAG_READONLY)        ? 'R' : '.',
   1630               (opt->flags & AV_OPT_FLAG_BSF_PARAM)       ? 'B' : '.',
   1631               (opt->flags & AV_OPT_FLAG_RUNTIME_PARAM)   ? 'T' : '.',
   1632               (opt->flags & AV_OPT_FLAG_DEPRECATED)      ? 'P' : '.');
   1633 
   1634        if (opt->help)
   1635            av_log(av_log_obj, AV_LOG_INFO, " %s", opt->help);
   1636 
   1637        if (av_opt_query_ranges(&r, obj, opt->name, AV_OPT_SEARCH_FAKE_OBJ) >= 0) {
   1638            switch (opt->type) {
   1639            case AV_OPT_TYPE_INT:
   1640            case AV_OPT_TYPE_UINT:
   1641            case AV_OPT_TYPE_INT64:
   1642            case AV_OPT_TYPE_UINT64:
   1643            case AV_OPT_TYPE_DOUBLE:
   1644            case AV_OPT_TYPE_FLOAT:
   1645            case AV_OPT_TYPE_RATIONAL:
   1646                for (i = 0; i < r->nb_ranges; i++) {
   1647                    av_log(av_log_obj, AV_LOG_INFO, " (from ");
   1648                    log_value(av_log_obj, AV_LOG_INFO, r->range[i]->value_min);
   1649                    av_log(av_log_obj, AV_LOG_INFO, " to ");
   1650                    log_value(av_log_obj, AV_LOG_INFO, r->range[i]->value_max);
   1651                    av_log(av_log_obj, AV_LOG_INFO, ")");
   1652                }
   1653                break;
   1654            }
   1655            av_opt_freep_ranges(&r);
   1656        }
   1657 
   1658        log_default(obj, av_log_obj, opt);
   1659 
   1660        av_log(av_log_obj, AV_LOG_INFO, "\n");
   1661        if (opt->unit && opt->type != AV_OPT_TYPE_CONST)
   1662            opt_list(obj, av_log_obj, opt->unit, req_flags, rej_flags, opt->type);
   1663    }
   1664 }
   1665 
   1666 int av_opt_show2(void *obj, void *av_log_obj, int req_flags, int rej_flags)
   1667 {
   1668    if (!obj)
   1669        return -1;
   1670 
   1671    av_log(av_log_obj, AV_LOG_INFO, "%s AVOptions:\n", (*(AVClass **)obj)->class_name);
   1672 
   1673    opt_list(obj, av_log_obj, NULL, req_flags, rej_flags, -1);
   1674 
   1675    return 0;
   1676 }
   1677 
   1678 void av_opt_set_defaults(void *s)
   1679 {
   1680    av_opt_set_defaults2(s, 0, 0);
   1681 }
   1682 
   1683 void av_opt_set_defaults2(void *s, int mask, int flags)
   1684 {
   1685    const AVOption *opt = NULL;
   1686    while ((opt = av_opt_next(s, opt))) {
   1687        void *dst = ((uint8_t*)s) + opt->offset;
   1688 
   1689        if ((opt->flags & mask) != flags)
   1690            continue;
   1691 
   1692        if (opt->flags & AV_OPT_FLAG_READONLY)
   1693            continue;
   1694 
   1695        if (opt->type & AV_OPT_TYPE_FLAG_ARRAY) {
   1696            const AVOptionArrayDef *arr = opt->default_val.arr;
   1697            const char              sep = opt_array_sep(opt);
   1698 
   1699            av_assert0(sep && sep != '\\' &&
   1700                       (sep < 'a' || sep > 'z') &&
   1701                       (sep < 'A' || sep > 'Z') &&
   1702                       (sep < '0' || sep > '9'));
   1703 
   1704            if (arr && arr->def)
   1705                opt_set_array(s, s, opt, arr->def, dst);
   1706 
   1707            continue;
   1708        }
   1709 
   1710        switch (opt->type) {
   1711            case AV_OPT_TYPE_CONST:
   1712                /* Nothing to be done here */
   1713                break;
   1714            case AV_OPT_TYPE_BOOL:
   1715            case AV_OPT_TYPE_FLAGS:
   1716            case AV_OPT_TYPE_INT:
   1717            case AV_OPT_TYPE_UINT:
   1718            case AV_OPT_TYPE_INT64:
   1719            case AV_OPT_TYPE_UINT64:
   1720            case AV_OPT_TYPE_DURATION:
   1721            case AV_OPT_TYPE_PIXEL_FMT:
   1722            case AV_OPT_TYPE_SAMPLE_FMT:
   1723                write_number(s, opt, dst, 1, 1, opt->default_val.i64);
   1724                break;
   1725            case AV_OPT_TYPE_DOUBLE:
   1726            case AV_OPT_TYPE_FLOAT: {
   1727                double val;
   1728                val = opt->default_val.dbl;
   1729                write_number(s, opt, dst, val, 1, 1);
   1730            }
   1731            break;
   1732            case AV_OPT_TYPE_RATIONAL: {
   1733                AVRational val;
   1734                val = av_d2q(opt->default_val.dbl, INT_MAX);
   1735                write_number(s, opt, dst, 1, val.den, val.num);
   1736            }
   1737            break;
   1738            case AV_OPT_TYPE_COLOR:
   1739                set_string_color(s, opt, opt->default_val.str, dst);
   1740                break;
   1741            case AV_OPT_TYPE_STRING:
   1742                set_string(s, opt, opt->default_val.str, dst);
   1743                break;
   1744            case AV_OPT_TYPE_IMAGE_SIZE:
   1745                set_string_image_size(s, opt, opt->default_val.str, dst);
   1746                break;
   1747            case AV_OPT_TYPE_VIDEO_RATE:
   1748                set_string_video_rate(s, opt, opt->default_val.str, dst);
   1749                break;
   1750            case AV_OPT_TYPE_BINARY:
   1751                set_string_binary(s, opt, opt->default_val.str, dst);
   1752                break;
   1753            case AV_OPT_TYPE_CHLAYOUT:
   1754                set_string_channel_layout(s, opt, opt->default_val.str, dst);
   1755                break;
   1756            case AV_OPT_TYPE_DICT:
   1757                set_string_dict(s, opt, opt->default_val.str, dst);
   1758                break;
   1759        default:
   1760            av_log(s, AV_LOG_DEBUG, "AVOption type %d of option %s not implemented yet\n",
   1761                   opt->type, opt->name);
   1762        }
   1763    }
   1764 }
   1765 
   1766 /**
   1767 * Store the value in the field in ctx that is named like key.
   1768 * ctx must be an AVClass context, storing is done using AVOptions.
   1769 *
   1770 * @param buf the string to parse, buf will be updated to point at the
   1771 * separator just after the parsed key/value pair
   1772 * @param key_val_sep a 0-terminated list of characters used to
   1773 * separate key from value
   1774 * @param pairs_sep a 0-terminated list of characters used to separate
   1775 * two pairs from each other
   1776 * @return 0 if the key/value pair has been successfully parsed and
   1777 * set, or a negative value corresponding to an AVERROR code in case
   1778 * of error:
   1779 * AVERROR(EINVAL) if the key/value pair cannot be parsed,
   1780 * the error code issued by av_opt_set() if the key/value pair
   1781 * cannot be set
   1782 */
   1783 static int parse_key_value_pair(void *ctx, const char **buf,
   1784                                const char *key_val_sep, const char *pairs_sep)
   1785 {
   1786    char *key = av_get_token(buf, key_val_sep);
   1787    char *val;
   1788    int ret;
   1789 
   1790    if (!key)
   1791        return AVERROR(ENOMEM);
   1792 
   1793    if (*key && strspn(*buf, key_val_sep)) {
   1794        (*buf)++;
   1795        val = av_get_token(buf, pairs_sep);
   1796        if (!val) {
   1797            av_freep(&key);
   1798            return AVERROR(ENOMEM);
   1799        }
   1800    } else {
   1801        av_log(ctx, AV_LOG_ERROR, "Missing key or no key/value separator found after key '%s'\n", key);
   1802        av_free(key);
   1803        return AVERROR(EINVAL);
   1804    }
   1805 
   1806    av_log(ctx, AV_LOG_DEBUG, "Setting entry with key '%s' to value '%s'\n", key, val);
   1807 
   1808    ret = av_opt_set(ctx, key, val, AV_OPT_SEARCH_CHILDREN);
   1809    if (ret == AVERROR_OPTION_NOT_FOUND)
   1810        av_log(ctx, AV_LOG_ERROR, "Key '%s' not found.\n", key);
   1811 
   1812    av_free(key);
   1813    av_free(val);
   1814    return ret;
   1815 }
   1816 
   1817 int av_set_options_string(void *ctx, const char *opts,
   1818                          const char *key_val_sep, const char *pairs_sep)
   1819 {
   1820    int ret, count = 0;
   1821 
   1822    if (!opts)
   1823        return 0;
   1824 
   1825    while (*opts) {
   1826        if ((ret = parse_key_value_pair(ctx, &opts, key_val_sep, pairs_sep)) < 0)
   1827            return ret;
   1828        count++;
   1829 
   1830        if (*opts)
   1831            opts++;
   1832    }
   1833 
   1834    return count;
   1835 }
   1836 
   1837 #define WHITESPACES " \n\t\r"
   1838 
   1839 static int is_key_char(char c)
   1840 {
   1841    return (unsigned)((c | 32) - 'a') < 26 ||
   1842           (unsigned)(c - '0') < 10 ||
   1843           c == '-' || c == '_' || c == '/' || c == '.';
   1844 }
   1845 
   1846 /**
   1847 * Read a key from a string.
   1848 *
   1849 * The key consists of is_key_char characters and must be terminated by a
   1850 * character from the delim string; spaces are ignored.
   1851 *
   1852 * @return  0 for success (even with ellipsis), <0 for failure
   1853 */
   1854 static int get_key(const char **ropts, const char *delim, char **rkey)
   1855 {
   1856    const char *opts = *ropts;
   1857    const char *key_start, *key_end;
   1858 
   1859    key_start = opts += strspn(opts, WHITESPACES);
   1860    while (is_key_char(*opts))
   1861        opts++;
   1862    key_end = opts;
   1863    opts += strspn(opts, WHITESPACES);
   1864    if (!*opts || !strchr(delim, *opts))
   1865        return AVERROR(EINVAL);
   1866    opts++;
   1867    if (!(*rkey = av_malloc(key_end - key_start + 1)))
   1868        return AVERROR(ENOMEM);
   1869    memcpy(*rkey, key_start, key_end - key_start);
   1870    (*rkey)[key_end - key_start] = 0;
   1871    *ropts = opts;
   1872    return 0;
   1873 }
   1874 
   1875 int av_opt_get_key_value(const char **ropts,
   1876                         const char *key_val_sep, const char *pairs_sep,
   1877                         unsigned flags,
   1878                         char **rkey, char **rval)
   1879 {
   1880    int ret;
   1881    char *key = NULL, *val;
   1882    const char *opts = *ropts;
   1883 
   1884    if ((ret = get_key(&opts, key_val_sep, &key)) < 0 &&
   1885        !(flags & AV_OPT_FLAG_IMPLICIT_KEY))
   1886        return AVERROR(EINVAL);
   1887    if (!(val = av_get_token(&opts, pairs_sep))) {
   1888        av_free(key);
   1889        return AVERROR(ENOMEM);
   1890    }
   1891    *ropts = opts;
   1892    *rkey  = key;
   1893    *rval  = val;
   1894    return 0;
   1895 }
   1896 
   1897 int av_opt_set_from_string(void *ctx, const char *opts,
   1898                           const char *const *shorthand,
   1899                           const char *key_val_sep, const char *pairs_sep)
   1900 {
   1901    int ret, count = 0;
   1902    const char *dummy_shorthand = NULL;
   1903    const char *key;
   1904 
   1905    if (!opts)
   1906        return 0;
   1907    if (!shorthand)
   1908        shorthand = &dummy_shorthand;
   1909 
   1910    while (*opts) {
   1911        char *parsed_key, *value;
   1912        ret = av_opt_get_key_value(&opts, key_val_sep, pairs_sep,
   1913                                   *shorthand ? AV_OPT_FLAG_IMPLICIT_KEY : 0,
   1914                                   &parsed_key, &value);
   1915        if (ret < 0) {
   1916            if (ret == AVERROR(EINVAL))
   1917                av_log(ctx, AV_LOG_ERROR, "No option name near '%s'\n", opts);
   1918            else
   1919                av_log(ctx, AV_LOG_ERROR, "Unable to parse '%s': %s\n", opts,
   1920                       av_err2str(ret));
   1921            return ret;
   1922        }
   1923        if (*opts)
   1924            opts++;
   1925        if (parsed_key) {
   1926            key = parsed_key;
   1927            while (*shorthand) /* discard all remaining shorthand */
   1928                shorthand++;
   1929        } else {
   1930            key = *(shorthand++);
   1931        }
   1932 
   1933        av_log(ctx, AV_LOG_DEBUG, "Setting '%s' to value '%s'\n", key, value);
   1934        if ((ret = av_opt_set(ctx, key, value, 0)) < 0) {
   1935            if (ret == AVERROR_OPTION_NOT_FOUND)
   1936                av_log(ctx, AV_LOG_ERROR, "Option '%s' not found\n", key);
   1937            av_free(value);
   1938            av_free(parsed_key);
   1939            return ret;
   1940        }
   1941 
   1942        av_free(value);
   1943        av_free(parsed_key);
   1944        count++;
   1945    }
   1946    return count;
   1947 }
   1948 
   1949 void av_opt_free(void *obj)
   1950 {
   1951    const AVOption *o = NULL;
   1952    while ((o = av_opt_next(obj, o))) {
   1953        void *pitem = (uint8_t *)obj + o->offset;
   1954 
   1955        if (o->type & AV_OPT_TYPE_FLAG_ARRAY)
   1956            opt_free_array(o, pitem, opt_array_pcount(pitem));
   1957        else
   1958            opt_free_elem(o->type, pitem);
   1959    }
   1960 }
   1961 
   1962 int av_opt_set_dict2(void *obj, AVDictionary **options, int search_flags)
   1963 {
   1964    const AVDictionaryEntry *t = NULL;
   1965    AVDictionary    *tmp = NULL;
   1966    int ret;
   1967 
   1968    if (!options)
   1969        return 0;
   1970 
   1971    while ((t = av_dict_iterate(*options, t))) {
   1972        ret = av_opt_set(obj, t->key, t->value, search_flags);
   1973        if (ret == AVERROR_OPTION_NOT_FOUND)
   1974            ret = av_dict_set(&tmp, t->key, t->value, AV_DICT_MULTIKEY);
   1975        if (ret < 0) {
   1976            av_log(obj, AV_LOG_ERROR, "Error setting option %s to value %s.\n", t->key, t->value);
   1977            av_dict_free(&tmp);
   1978            return ret;
   1979        }
   1980    }
   1981    av_dict_free(options);
   1982    *options = tmp;
   1983    return 0;
   1984 }
   1985 
   1986 int av_opt_set_dict(void *obj, AVDictionary **options)
   1987 {
   1988    return av_opt_set_dict2(obj, options, 0);
   1989 }
   1990 
   1991 const AVOption *av_opt_find(void *obj, const char *name, const char *unit,
   1992                            int opt_flags, int search_flags)
   1993 {
   1994    return av_opt_find2(obj, name, unit, opt_flags, search_flags, NULL);
   1995 }
   1996 
   1997 const AVOption *av_opt_find2(void *obj, const char *name, const char *unit,
   1998                             int opt_flags, int search_flags, void **target_obj)
   1999 {
   2000    const AVClass  *c;
   2001    const AVOption *o = NULL;
   2002 
   2003    if(!obj)
   2004        return NULL;
   2005 
   2006    c= *(AVClass**)obj;
   2007 
   2008    if (!c)
   2009        return NULL;
   2010 
   2011    if (search_flags & AV_OPT_SEARCH_CHILDREN) {
   2012        if (search_flags & AV_OPT_SEARCH_FAKE_OBJ) {
   2013            void *iter = NULL;
   2014            const AVClass *child;
   2015            while (child = av_opt_child_class_iterate(c, &iter))
   2016                if (o = av_opt_find2(&child, name, unit, opt_flags, search_flags, NULL))
   2017                    return o;
   2018        } else {
   2019            void *child = NULL;
   2020            while (child = av_opt_child_next(obj, child))
   2021                if (o = av_opt_find2(child, name, unit, opt_flags, search_flags, target_obj))
   2022                    return o;
   2023        }
   2024    }
   2025 
   2026    while (o = av_opt_next(obj, o)) {
   2027        if (!strcmp(o->name, name) && (o->flags & opt_flags) == opt_flags &&
   2028            ((!unit && o->type != AV_OPT_TYPE_CONST) ||
   2029             (unit  && o->type == AV_OPT_TYPE_CONST && o->unit && !strcmp(o->unit, unit)))) {
   2030            if (target_obj) {
   2031                if (!(search_flags & AV_OPT_SEARCH_FAKE_OBJ))
   2032                    *target_obj = obj;
   2033                else
   2034                    *target_obj = NULL;
   2035            }
   2036            return o;
   2037        }
   2038    }
   2039    return NULL;
   2040 }
   2041 
   2042 void *av_opt_child_next(void *obj, void *prev)
   2043 {
   2044    const AVClass *c = *(AVClass **)obj;
   2045    if (c->child_next)
   2046        return c->child_next(obj, prev);
   2047    return NULL;
   2048 }
   2049 
   2050 const AVClass *av_opt_child_class_iterate(const AVClass *parent, void **iter)
   2051 {
   2052    if (parent->child_class_iterate)
   2053        return parent->child_class_iterate(iter);
   2054    return NULL;
   2055 }
   2056 
   2057 #if FF_API_OPT_PTR
   2058 void *av_opt_ptr(const AVClass *class, void *obj, const char *name)
   2059 {
   2060    const AVOption *opt= av_opt_find2(&class, name, NULL, 0, AV_OPT_SEARCH_FAKE_OBJ, NULL);
   2061 
   2062    // no direct access to array-type options
   2063    if (!opt || (opt->type & AV_OPT_TYPE_FLAG_ARRAY))
   2064        return NULL;
   2065    return (uint8_t*)obj + opt->offset;
   2066 }
   2067 #endif
   2068 
   2069 static int opt_copy_elem(void *logctx, enum AVOptionType type,
   2070                         void *dst, const void *src)
   2071 {
   2072    if (type == AV_OPT_TYPE_STRING) {
   2073        const char *src_str = *(const char *const *)src;
   2074        char         **dstp =  (char **)dst;
   2075        if (*dstp != src_str)
   2076            av_freep(dstp);
   2077        if (src_str) {
   2078            *dstp = av_strdup(src_str);
   2079            if (!*dstp)
   2080                return AVERROR(ENOMEM);
   2081        }
   2082    } else if (type == AV_OPT_TYPE_BINARY) {
   2083        const uint8_t *const *src8 = (const uint8_t *const *)src;
   2084        uint8_t             **dst8 = (uint8_t **)dst;
   2085        int len = *(const int *)(src8 + 1);
   2086        if (*dst8 != *src8)
   2087            av_freep(dst8);
   2088        *dst8 = av_memdup(*src8, len);
   2089        if (len && !*dst8) {
   2090            *(int *)(dst8 + 1) = 0;
   2091            return AVERROR(ENOMEM);
   2092        }
   2093        *(int *)(dst8 + 1) = len;
   2094    } else if (type == AV_OPT_TYPE_CONST) {
   2095        // do nothing
   2096    } else if (type == AV_OPT_TYPE_DICT) {
   2097        const AVDictionary *sdict = *(const AVDictionary * const *)src;
   2098        AVDictionary     **ddictp = (AVDictionary **)dst;
   2099        if (sdict != *ddictp)
   2100            av_dict_free(ddictp);
   2101        *ddictp = NULL;
   2102        return av_dict_copy(ddictp, sdict, 0);
   2103    } else if (type == AV_OPT_TYPE_CHLAYOUT) {
   2104        if (dst != src)
   2105            return av_channel_layout_copy(dst, src);
   2106    } else if (opt_is_pod(type)) {
   2107        size_t size = opt_type_desc[type].size;
   2108        memcpy(dst, src, size);
   2109    } else {
   2110        av_log(logctx, AV_LOG_ERROR, "Unhandled option type: %d\n", type);
   2111        return AVERROR(EINVAL);
   2112    }
   2113 
   2114    return 0;
   2115 }
   2116 
   2117 static int opt_copy_array(void *logctx, const AVOption *o,
   2118                          void **pdst, const void * const *psrc)
   2119 {
   2120    unsigned nb_elems = *opt_array_pcount(psrc);
   2121    void         *dst = NULL;
   2122    int ret;
   2123 
   2124    if (*pdst == *psrc) {
   2125        *pdst                   = NULL;
   2126        *opt_array_pcount(pdst) = 0;
   2127    }
   2128 
   2129    opt_free_array(o, pdst, opt_array_pcount(pdst));
   2130 
   2131    dst = av_calloc(nb_elems, opt_type_desc[TYPE_BASE(o->type)].size);
   2132    if (!dst)
   2133        return AVERROR(ENOMEM);
   2134 
   2135    for (unsigned i = 0; i < nb_elems; i++) {
   2136        ret = opt_copy_elem(logctx, TYPE_BASE(o->type),
   2137                            opt_array_pelem(o, dst, i),
   2138                            opt_array_pelem(o, *(void**)psrc, i));
   2139        if (ret < 0) {
   2140            opt_free_array(o, &dst, &nb_elems);
   2141            return ret;
   2142        }
   2143    }
   2144 
   2145    *pdst                   = dst;
   2146    *opt_array_pcount(pdst) = nb_elems;
   2147 
   2148    return 0;
   2149 }
   2150 
   2151 int av_opt_copy(void *dst, const void *src)
   2152 {
   2153    const AVOption *o = NULL;
   2154    const AVClass *c;
   2155    int ret = 0;
   2156 
   2157    if (!src)
   2158        return AVERROR(EINVAL);
   2159 
   2160    c = *(AVClass **)src;
   2161    if (!c || c != *(AVClass **)dst)
   2162        return AVERROR(EINVAL);
   2163 
   2164    while ((o = av_opt_next(src, o))) {
   2165        void *field_dst = (uint8_t *)dst + o->offset;
   2166        void *field_src = (uint8_t *)src + o->offset;
   2167 
   2168        int err = (o->type & AV_OPT_TYPE_FLAG_ARRAY)                 ?
   2169                  opt_copy_array(dst, o,       field_dst, field_src) :
   2170                  opt_copy_elem (dst, o->type, field_dst, field_src);
   2171        if (err < 0)
   2172            ret = err;
   2173    }
   2174    return ret;
   2175 }
   2176 
   2177 int av_opt_get_array_size(void *obj, const char *name, int search_flags,
   2178                          unsigned int *out_val)
   2179 {
   2180    void *target_obj, *parray;
   2181    const AVOption *o;
   2182 
   2183    o = av_opt_find2(obj, name, NULL, 0, search_flags, &target_obj);
   2184    if (!o || !target_obj)
   2185        return AVERROR_OPTION_NOT_FOUND;
   2186    if (!(o->type & AV_OPT_TYPE_FLAG_ARRAY))
   2187        return AVERROR(EINVAL);
   2188 
   2189    parray = (uint8_t *)target_obj + o->offset;
   2190    *out_val = *opt_array_pcount(parray);
   2191 
   2192    return 0;
   2193 }
   2194 
   2195 int av_opt_get_array(void *obj, const char *name, int search_flags,
   2196                     unsigned int start_elem, unsigned int nb_elems,
   2197                     enum AVOptionType out_type, void *out_val)
   2198 {
   2199    const size_t elem_size_out = opt_type_desc[TYPE_BASE(out_type)].size;
   2200 
   2201    const AVOption *o;
   2202    void *target_obj;
   2203 
   2204    const void *parray;
   2205    unsigned array_size;
   2206 
   2207    int ret;
   2208 
   2209    o = av_opt_find2(obj, name, NULL, 0, search_flags, &target_obj);
   2210    if (!o || !target_obj)
   2211        return AVERROR_OPTION_NOT_FOUND;
   2212    if (!(o->type & AV_OPT_TYPE_FLAG_ARRAY) ||
   2213        (out_type & AV_OPT_TYPE_FLAG_ARRAY))
   2214        return AVERROR(EINVAL);
   2215 
   2216    parray     = (uint8_t *)target_obj + o->offset;
   2217    array_size = *opt_array_pcount(parray);
   2218 
   2219    if (start_elem >= array_size ||
   2220        array_size - start_elem < nb_elems)
   2221        return AVERROR(EINVAL);
   2222 
   2223    for (unsigned i = 0; i < nb_elems; i++) {
   2224        const void *src = opt_array_pelem(o, *(void**)parray, start_elem + i);
   2225        void       *dst = (uint8_t*)out_val + i * elem_size_out;
   2226 
   2227        if (out_type == TYPE_BASE(o->type)) {
   2228            ret = opt_copy_elem(obj, out_type, dst, src);
   2229            if (ret < 0)
   2230                goto fail;
   2231        } else if (out_type == AV_OPT_TYPE_STRING) {
   2232            uint8_t buf[128], *out = buf;
   2233 
   2234            ret = opt_get_elem(o, &out, sizeof(buf), src, search_flags);
   2235            if (ret < 0)
   2236                goto fail;
   2237 
   2238            if (out == buf) {
   2239                out = av_strdup(buf);
   2240                if (!out) {
   2241                    ret = AVERROR(ENOMEM);
   2242                    goto fail;
   2243                }
   2244            }
   2245 
   2246            *(uint8_t**)dst = out;
   2247        } else if (out_type == AV_OPT_TYPE_INT64    ||
   2248                   out_type == AV_OPT_TYPE_DOUBLE   ||
   2249                   out_type == AV_OPT_TYPE_RATIONAL) {
   2250            double     num = 1.0;
   2251            int        den = 1;
   2252            int64_t intnum = 1;
   2253 
   2254            ret = read_number(o, src, &num, &den, &intnum);
   2255            if (ret < 0)
   2256                goto fail;
   2257 
   2258            switch (out_type) {
   2259            case AV_OPT_TYPE_INT64:
   2260                *(int64_t*)dst = (num == den) ?  intnum : num * intnum / den;
   2261                break;
   2262            case AV_OPT_TYPE_DOUBLE:
   2263                *(double*)dst = num * intnum / den;
   2264                break;
   2265            case AV_OPT_TYPE_RATIONAL:
   2266                *(AVRational*)dst = (num == 1.0 && (int)intnum == intnum) ?
   2267                                    (AVRational){ intnum, den }           :
   2268                                    double_to_rational(num * intnum / den);
   2269                break;
   2270            default: av_assert0(0);
   2271            }
   2272        } else
   2273            return AVERROR(ENOSYS);
   2274    }
   2275 
   2276    return 0;
   2277 fail:
   2278    for (unsigned i = 0; i < nb_elems; i++)
   2279        opt_free_elem(out_type, (uint8_t*)out_val + i * elem_size_out);
   2280    return ret;
   2281 }
   2282 
   2283 int av_opt_set_array(void *obj, const char *name, int search_flags,
   2284                     unsigned int start_elem, unsigned int nb_elems,
   2285                     enum AVOptionType val_type, const void *val)
   2286 {
   2287    const size_t elem_size_val = opt_type_desc[TYPE_BASE(val_type)].size;
   2288 
   2289    const AVOption *o;
   2290    const AVOptionArrayDef *arr;
   2291    void *target_obj;
   2292 
   2293    void *parray;
   2294    void *new_elems;
   2295    unsigned *array_size, new_size;
   2296    size_t elem_size;
   2297 
   2298    int ret = 0;
   2299 
   2300    ret = opt_set_init(obj, name, search_flags, 0, &target_obj, &o, &parray);
   2301    if (ret < 0)
   2302        return ret;
   2303 
   2304    if (!(o->type & AV_OPT_TYPE_FLAG_ARRAY) ||
   2305        (val_type & AV_OPT_TYPE_FLAG_ARRAY))
   2306        return AVERROR(EINVAL);
   2307 
   2308    arr        = o->default_val.arr;
   2309    array_size = opt_array_pcount(parray);
   2310    elem_size  = opt_type_desc[TYPE_BASE(o->type)].size;
   2311 
   2312    if (start_elem > *array_size)
   2313        return AVERROR(EINVAL);
   2314 
   2315    // compute new array size
   2316    if (!val) {
   2317        if (*array_size - start_elem < nb_elems)
   2318            return AVERROR(EINVAL);
   2319 
   2320        new_size = *array_size - nb_elems;
   2321    } else if (search_flags & AV_OPT_ARRAY_REPLACE) {
   2322        if (start_elem >= UINT_MAX - nb_elems)
   2323            return AVERROR(EINVAL);
   2324 
   2325        new_size = FFMAX(*array_size, start_elem + nb_elems);
   2326    } else {
   2327        if (nb_elems >= UINT_MAX - *array_size)
   2328            return AVERROR(EINVAL);
   2329 
   2330        new_size = *array_size + nb_elems;
   2331    }
   2332 
   2333    if (arr &&
   2334        ((arr->size_max && new_size > arr->size_max) ||
   2335         (arr->size_min && new_size < arr->size_min)))
   2336        return AVERROR(EINVAL);
   2337 
   2338    // desired operation is shrinking the array
   2339    if (!val) {
   2340        void *array = *(void**)parray;
   2341 
   2342        for (unsigned i = 0; i < nb_elems; i++) {
   2343            opt_free_elem(o->type,
   2344                          opt_array_pelem(o, array, start_elem + i));
   2345        }
   2346 
   2347        if (new_size > 0) {
   2348            memmove(opt_array_pelem(o, array, start_elem),
   2349                    opt_array_pelem(o, array, start_elem + nb_elems),
   2350                    elem_size * (*array_size - start_elem - nb_elems));
   2351 
   2352            array = av_realloc_array(array, new_size, elem_size);
   2353            if (!array)
   2354                return AVERROR(ENOMEM);
   2355 
   2356            *(void**)parray = array;
   2357        } else
   2358            av_freep(parray);
   2359 
   2360        *array_size = new_size;
   2361 
   2362        return 0;
   2363    }
   2364 
   2365    // otherwise, desired operation is insert/replace;
   2366    // first, store new elements in a separate array to simplify
   2367    // rollback on failure
   2368    new_elems = av_calloc(nb_elems, elem_size);
   2369    if (!new_elems)
   2370        return AVERROR(ENOMEM);
   2371 
   2372    // convert/validate each new element
   2373    for (unsigned i = 0; i < nb_elems; i++) {
   2374        void       *dst = opt_array_pelem(o, new_elems, i);
   2375        const void *src = (uint8_t*)val + i * elem_size_val;
   2376 
   2377        double     num = 1.0;
   2378        int        den = 1;
   2379        int64_t intnum = 1;
   2380 
   2381        if (val_type == TYPE_BASE(o->type)) {
   2382            int err;
   2383 
   2384            ret = opt_copy_elem(obj, val_type, dst, src);
   2385            if (ret < 0)
   2386                goto fail;
   2387 
   2388            // validate the range for numeric options
   2389            err = read_number(o, dst, &num, &den, &intnum);
   2390            if (err >= 0 && TYPE_BASE(o->type) != AV_OPT_TYPE_FLAGS &&
   2391                (!den || o->max * den < num * intnum || o->min * den > num * intnum)) {
   2392                num = den ? num * intnum / den : (num && intnum ? INFINITY : NAN);
   2393                av_log(obj, AV_LOG_ERROR, "Cannot set array element %u for "
   2394                       "parameter '%s': value %f out of range [%g - %g]\n",
   2395                       start_elem + i, o->name, num, o->min, o->max);
   2396                ret = AVERROR(ERANGE);
   2397                goto fail;
   2398            }
   2399        } else if (val_type == AV_OPT_TYPE_STRING) {
   2400            ret = opt_set_elem(obj, target_obj, o, *(const char **)src, dst);
   2401            if (ret < 0)
   2402                goto fail;
   2403        } else if (val_type == AV_OPT_TYPE_INT ||
   2404              val_type == AV_OPT_TYPE_INT64    ||
   2405              val_type == AV_OPT_TYPE_FLOAT    ||
   2406              val_type == AV_OPT_TYPE_DOUBLE   ||
   2407              val_type == AV_OPT_TYPE_RATIONAL) {
   2408 
   2409            switch (val_type) {
   2410            case AV_OPT_TYPE_INT:       intnum = *(int*)src;                break;
   2411            case AV_OPT_TYPE_INT64:     intnum = *(int64_t*)src;            break;
   2412            case AV_OPT_TYPE_FLOAT:     num    = *(float*)src;              break;
   2413            case AV_OPT_TYPE_DOUBLE:    num    = *(double*)src;             break;
   2414            case AV_OPT_TYPE_RATIONAL:  intnum = ((AVRational*)src)->num;
   2415                                        den    = ((AVRational*)src)->den;   break;
   2416            default: av_assert0(0);
   2417            }
   2418 
   2419            ret = write_number(obj, o, dst, num, den, intnum);
   2420            if (ret < 0)
   2421                goto fail;
   2422        } else {
   2423            ret = AVERROR(ENOSYS);
   2424            goto fail;
   2425        }
   2426    }
   2427 
   2428    // commit new elements to the array
   2429    if (start_elem == 0 && nb_elems == new_size) {
   2430        // replacing the existing array entirely
   2431        opt_free_array(o, parray, array_size);
   2432        *(void**)parray = new_elems;
   2433        *array_size     = nb_elems;
   2434 
   2435        new_elems = NULL;
   2436        nb_elems  = 0;
   2437    } else {
   2438        void *array = av_realloc_array(*(void**)parray, new_size, elem_size);
   2439        if (!array) {
   2440            ret = AVERROR(ENOMEM);
   2441            goto fail;
   2442        }
   2443 
   2444        if (search_flags & AV_OPT_ARRAY_REPLACE) {
   2445            // free the elements being overwritten
   2446            for (unsigned i = start_elem; i < FFMIN(start_elem + nb_elems, *array_size); i++)
   2447                opt_free_elem(o->type, opt_array_pelem(o, array, i));
   2448        } else {
   2449            // shift existing elements to the end
   2450            memmove(opt_array_pelem(o, array, start_elem + nb_elems),
   2451                    opt_array_pelem(o, array, start_elem),
   2452                    elem_size * (*array_size - start_elem));
   2453        }
   2454 
   2455        memcpy((uint8_t*)array + elem_size * start_elem, new_elems, elem_size * nb_elems);
   2456 
   2457        av_freep(&new_elems);
   2458        nb_elems = 0;
   2459 
   2460        *(void**)parray = array;
   2461        *array_size     = new_size;
   2462    }
   2463 
   2464 fail:
   2465    opt_free_array(o, &new_elems, &nb_elems);
   2466 
   2467    return ret;
   2468 }
   2469 
   2470 int av_opt_query_ranges(AVOptionRanges **ranges_arg, void *obj, const char *key, int flags)
   2471 {
   2472    int ret;
   2473    const AVClass *c = *(AVClass**)obj;
   2474    int (*callback)(AVOptionRanges **, void *obj, const char *key, int flags) = c->query_ranges;
   2475 
   2476    if (!callback)
   2477        callback = av_opt_query_ranges_default;
   2478 
   2479    ret = callback(ranges_arg, obj, key, flags);
   2480    if (ret >= 0) {
   2481        if (!(flags & AV_OPT_MULTI_COMPONENT_RANGE))
   2482            ret = 1;
   2483        (*ranges_arg)->nb_components = ret;
   2484    }
   2485    return ret;
   2486 }
   2487 
   2488 int av_opt_query_ranges_default(AVOptionRanges **ranges_arg, void *obj, const char *key, int flags)
   2489 {
   2490    AVOptionRanges *ranges = av_mallocz(sizeof(*ranges));
   2491    AVOptionRange **range_array = av_mallocz(sizeof(void*));
   2492    AVOptionRange *range = av_mallocz(sizeof(*range));
   2493    const AVOption *field = av_opt_find(obj, key, NULL, 0, flags);
   2494    int ret;
   2495 
   2496    *ranges_arg = NULL;
   2497 
   2498    if (!ranges || !range || !range_array || !field) {
   2499        ret = AVERROR(ENOMEM);
   2500        goto fail;
   2501    }
   2502 
   2503    ranges->range = range_array;
   2504    ranges->range[0] = range;
   2505    ranges->nb_ranges = 1;
   2506    ranges->nb_components = 1;
   2507    range->is_range = 1;
   2508    range->value_min = field->min;
   2509    range->value_max = field->max;
   2510 
   2511    switch (field->type) {
   2512    case AV_OPT_TYPE_BOOL:
   2513    case AV_OPT_TYPE_INT:
   2514    case AV_OPT_TYPE_UINT:
   2515    case AV_OPT_TYPE_INT64:
   2516    case AV_OPT_TYPE_UINT64:
   2517    case AV_OPT_TYPE_PIXEL_FMT:
   2518    case AV_OPT_TYPE_SAMPLE_FMT:
   2519    case AV_OPT_TYPE_FLOAT:
   2520    case AV_OPT_TYPE_DOUBLE:
   2521    case AV_OPT_TYPE_DURATION:
   2522    case AV_OPT_TYPE_COLOR:
   2523        break;
   2524    case AV_OPT_TYPE_STRING:
   2525        range->component_min = 0;
   2526        range->component_max = 0x10FFFF; // max unicode value
   2527        range->value_min = -1;
   2528        range->value_max = INT_MAX;
   2529        break;
   2530    case AV_OPT_TYPE_RATIONAL:
   2531        range->component_min = INT_MIN;
   2532        range->component_max = INT_MAX;
   2533        break;
   2534    case AV_OPT_TYPE_IMAGE_SIZE:
   2535        range->component_min = 0;
   2536        range->component_max = INT_MAX/128/8;
   2537        range->value_min = 0;
   2538        range->value_max = INT_MAX/8;
   2539        break;
   2540    case AV_OPT_TYPE_VIDEO_RATE:
   2541        range->component_min = 1;
   2542        range->component_max = INT_MAX;
   2543        range->value_min = 1;
   2544        range->value_max = INT_MAX;
   2545        break;
   2546    default:
   2547        ret = AVERROR(ENOSYS);
   2548        goto fail;
   2549    }
   2550 
   2551    *ranges_arg = ranges;
   2552    return 1;
   2553 fail:
   2554    av_free(ranges);
   2555    av_free(range);
   2556    av_free(range_array);
   2557    return ret;
   2558 }
   2559 
   2560 void av_opt_freep_ranges(AVOptionRanges **rangesp)
   2561 {
   2562    int i;
   2563    AVOptionRanges *ranges = *rangesp;
   2564 
   2565    if (!ranges)
   2566        return;
   2567 
   2568    for (i = 0; i < ranges->nb_ranges * ranges->nb_components; i++) {
   2569        AVOptionRange *range = ranges->range[i];
   2570        if (range) {
   2571            av_freep(&range->str);
   2572            av_freep(&ranges->range[i]);
   2573        }
   2574    }
   2575    av_freep(&ranges->range);
   2576    av_freep(rangesp);
   2577 }
   2578 
   2579 int av_opt_is_set_to_default(void *obj, const AVOption *o)
   2580 {
   2581    int64_t i64;
   2582    double d;
   2583    AVRational q;
   2584    int ret, w, h;
   2585    char *str;
   2586    void *dst;
   2587 
   2588    if (!o || !obj)
   2589        return AVERROR(EINVAL);
   2590 
   2591    dst = ((uint8_t*)obj) + o->offset;
   2592 
   2593    if (o->type & AV_OPT_TYPE_FLAG_ARRAY) {
   2594        const char *def = o->default_val.arr ? o->default_val.arr->def : NULL;
   2595        uint8_t *val;
   2596 
   2597        ret = opt_get_array(o, dst, &val);
   2598        if (ret < 0)
   2599            return ret;
   2600 
   2601        if (!!val != !!def)
   2602            ret = 0;
   2603        else if (val)
   2604            ret = !strcmp(val, def);
   2605 
   2606        av_freep(&val);
   2607 
   2608        return ret;
   2609    }
   2610 
   2611    switch (o->type) {
   2612    case AV_OPT_TYPE_CONST:
   2613        return 1;
   2614    case AV_OPT_TYPE_BOOL:
   2615    case AV_OPT_TYPE_FLAGS:
   2616    case AV_OPT_TYPE_PIXEL_FMT:
   2617    case AV_OPT_TYPE_SAMPLE_FMT:
   2618    case AV_OPT_TYPE_INT:
   2619    case AV_OPT_TYPE_UINT:
   2620    case AV_OPT_TYPE_DURATION:
   2621    case AV_OPT_TYPE_INT64:
   2622    case AV_OPT_TYPE_UINT64:
   2623        read_number(o, dst, NULL, NULL, &i64);
   2624        return o->default_val.i64 == i64;
   2625    case AV_OPT_TYPE_CHLAYOUT: {
   2626        AVChannelLayout ch_layout = { 0 };
   2627        if (o->default_val.str) {
   2628            if ((ret = av_channel_layout_from_string(&ch_layout, o->default_val.str)) < 0)
   2629                return ret;
   2630        }
   2631        ret = !av_channel_layout_compare((AVChannelLayout *)dst, &ch_layout);
   2632        av_channel_layout_uninit(&ch_layout);
   2633        return ret;
   2634    }
   2635    case AV_OPT_TYPE_STRING:
   2636        str = *(char **)dst;
   2637        if (str == o->default_val.str) //2 NULLs
   2638            return 1;
   2639        if (!str || !o->default_val.str) //1 NULL
   2640            return 0;
   2641        return !strcmp(str, o->default_val.str);
   2642    case AV_OPT_TYPE_DOUBLE:
   2643        d = *(double *)dst;
   2644        return o->default_val.dbl == d;
   2645    case AV_OPT_TYPE_FLOAT:
   2646        d = *(float *)dst;
   2647        return (float)o->default_val.dbl == d;
   2648    case AV_OPT_TYPE_RATIONAL:
   2649        q = av_d2q(o->default_val.dbl, INT_MAX);
   2650        return !av_cmp_q(*(AVRational*)dst, q);
   2651    case AV_OPT_TYPE_BINARY: {
   2652        struct {
   2653            uint8_t *data;
   2654            int size;
   2655        } tmp = {0};
   2656        int opt_size = *(int *)((void **)dst + 1);
   2657        void *opt_ptr = *(void **)dst;
   2658        if (!opt_size && (!o->default_val.str || !strlen(o->default_val.str)))
   2659            return 1;
   2660        if (!opt_size ||  !o->default_val.str || !strlen(o->default_val.str ))
   2661            return 0;
   2662        if (opt_size != strlen(o->default_val.str) / 2)
   2663            return 0;
   2664        ret = set_string_binary(NULL, NULL, o->default_val.str, &tmp.data);
   2665        if (!ret)
   2666            ret = !memcmp(opt_ptr, tmp.data, tmp.size);
   2667        av_free(tmp.data);
   2668        return ret;
   2669    }
   2670    case AV_OPT_TYPE_DICT: {
   2671        AVDictionary *dict1 = NULL;
   2672        AVDictionary *dict2 = *(AVDictionary **)dst;
   2673        const AVDictionaryEntry *en1 = NULL;
   2674        const AVDictionaryEntry *en2 = NULL;
   2675        ret = av_dict_parse_string(&dict1, o->default_val.str, "=", ":", 0);
   2676        if (ret < 0) {
   2677            av_dict_free(&dict1);
   2678            return ret;
   2679        }
   2680        do {
   2681            en1 = av_dict_iterate(dict1, en1);
   2682            en2 = av_dict_iterate(dict2, en2);
   2683        } while (en1 && en2 && !strcmp(en1->key, en2->key) && !strcmp(en1->value, en2->value));
   2684        av_dict_free(&dict1);
   2685        return (!en1 && !en2);
   2686    }
   2687    case AV_OPT_TYPE_IMAGE_SIZE:
   2688        if (!o->default_val.str || !strcmp(o->default_val.str, "none"))
   2689            w = h = 0;
   2690        else if ((ret = av_parse_video_size(&w, &h, o->default_val.str)) < 0)
   2691            return ret;
   2692        return (w == *(int *)dst) && (h == *((int *)dst+1));
   2693    case AV_OPT_TYPE_VIDEO_RATE:
   2694        q = (AVRational){0, 0};
   2695        if (o->default_val.str) {
   2696            if ((ret = av_parse_video_rate(&q, o->default_val.str)) < 0)
   2697                return ret;
   2698        }
   2699        return !av_cmp_q(*(AVRational*)dst, q);
   2700    case AV_OPT_TYPE_COLOR: {
   2701        uint8_t color[4] = {0, 0, 0, 0};
   2702        if (o->default_val.str) {
   2703            if ((ret = av_parse_color(color, o->default_val.str, -1, NULL)) < 0)
   2704                return ret;
   2705        }
   2706        return !memcmp(color, dst, sizeof(color));
   2707    }
   2708    default:
   2709        av_log(obj, AV_LOG_WARNING, "Not supported option type: %d, option name: %s\n", o->type, o->name);
   2710        break;
   2711    }
   2712    return AVERROR_PATCHWELCOME;
   2713 }
   2714 
   2715 int av_opt_is_set_to_default_by_name(void *obj, const char *name, int search_flags)
   2716 {
   2717    const AVOption *o;
   2718    void *target;
   2719    if (!obj)
   2720        return AVERROR(EINVAL);
   2721    o = av_opt_find2(obj, name, NULL, 0, search_flags, &target);
   2722    if (!o)
   2723        return AVERROR_OPTION_NOT_FOUND;
   2724    return av_opt_is_set_to_default(target, o);
   2725 }
   2726 
   2727 static int opt_serialize(void *obj, int opt_flags, int flags, int *cnt,
   2728                         AVBPrint *bprint, const char key_val_sep, const char pairs_sep)
   2729 {
   2730    const AVOption *o = NULL;
   2731    void *child = NULL;
   2732    uint8_t *buf;
   2733    int ret;
   2734    const char special_chars[] = {pairs_sep, key_val_sep, '\0'};
   2735 
   2736    if (flags & AV_OPT_SERIALIZE_SEARCH_CHILDREN)
   2737        while (child = av_opt_child_next(obj, child)) {
   2738            ret = opt_serialize(child, opt_flags, flags, cnt, bprint,
   2739                                key_val_sep, pairs_sep);
   2740            if (ret < 0)
   2741                return ret;
   2742        }
   2743 
   2744    while (o = av_opt_next(obj, o)) {
   2745        if (o->type == AV_OPT_TYPE_CONST)
   2746            continue;
   2747        if ((flags & AV_OPT_SERIALIZE_OPT_FLAGS_EXACT) && o->flags != opt_flags)
   2748            continue;
   2749        else if (((o->flags & opt_flags) != opt_flags))
   2750            continue;
   2751        if (flags & AV_OPT_SERIALIZE_SKIP_DEFAULTS && av_opt_is_set_to_default(obj, o) > 0)
   2752            continue;
   2753        if ((ret = av_opt_get(obj, o->name, 0, &buf)) < 0) {
   2754            av_bprint_finalize(bprint, NULL);
   2755            return ret;
   2756        }
   2757        if (buf) {
   2758            if ((*cnt)++)
   2759                av_bprint_append_data(bprint, &pairs_sep, 1);
   2760            av_bprint_escape(bprint, o->name, special_chars, AV_ESCAPE_MODE_BACKSLASH, 0);
   2761            av_bprint_append_data(bprint, &key_val_sep, 1);
   2762            av_bprint_escape(bprint, buf, special_chars, AV_ESCAPE_MODE_BACKSLASH, 0);
   2763            av_freep(&buf);
   2764        }
   2765    }
   2766 
   2767    return 0;
   2768 }
   2769 
   2770 int av_opt_serialize(void *obj, int opt_flags, int flags, char **buffer,
   2771                     const char key_val_sep, const char pairs_sep)
   2772 {
   2773    AVBPrint bprint;
   2774    int ret, cnt = 0;
   2775 
   2776    if (pairs_sep == '\0' || key_val_sep == '\0' || pairs_sep == key_val_sep ||
   2777        pairs_sep == '\\' || key_val_sep == '\\') {
   2778        av_log(obj, AV_LOG_ERROR, "Invalid separator(s) found.");
   2779        return AVERROR(EINVAL);
   2780    }
   2781 
   2782    if (!obj || !buffer)
   2783        return AVERROR(EINVAL);
   2784 
   2785    *buffer = NULL;
   2786    av_bprint_init(&bprint, 64, AV_BPRINT_SIZE_UNLIMITED);
   2787 
   2788    ret = opt_serialize(obj, opt_flags, flags, &cnt, &bprint,
   2789                        key_val_sep, pairs_sep);
   2790    if (ret < 0)
   2791        return ret;
   2792 
   2793    ret = av_bprint_finalize(&bprint, buffer);
   2794    if (ret < 0)
   2795        return ret;
   2796    return 0;
   2797 }