tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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av1_parse.c (3702B)

      1 /*
      2 * AV1 common parsing code
      3 *
      4 * This file is part of FFmpeg.
      5 *
      6 * FFmpeg is free software; you can redistribute it and/or
      7 * modify it under the terms of the GNU Lesser General Public
      8 * License as published by the Free Software Foundation; either
      9 * version 2.1 of the License, or (at your option) any later version.
     10 *
     11 * FFmpeg is distributed in the hope that it will be useful,
     12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14 * Lesser General Public License for more details.
     15 *
     16 * You should have received a copy of the GNU Lesser General Public
     17 * License along with FFmpeg; if not, write to the Free Software
     18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
     19 */
     20 
     21 #include "config.h"
     22 
     23 #include "libavutil/mem.h"
     24 
     25 #include "av1.h"
     26 #include "av1_parse.h"
     27 #include "bytestream.h"
     28 
     29 int ff_av1_extract_obu(AV1OBU *obu, const uint8_t *buf, int length, void *logctx)
     30 {
     31    int64_t obu_size;
     32    int start_pos, type, temporal_id, spatial_id;
     33    int len;
     34 
     35    len = parse_obu_header(buf, length, &obu_size, &start_pos,
     36                           &type, &temporal_id, &spatial_id);
     37    if (len < 0)
     38        return len;
     39 
     40    obu->type        = type;
     41    obu->temporal_id = temporal_id;
     42    obu->spatial_id  = spatial_id;
     43 
     44    obu->data     = buf + start_pos;
     45    obu->size     = obu_size;
     46    obu->raw_data = buf;
     47    obu->raw_size = len;
     48 
     49    av_log(logctx, AV_LOG_DEBUG,
     50           "obu_type: %d, temporal_id: %d, spatial_id: %d, payload size: %d\n",
     51           obu->type, obu->temporal_id, obu->spatial_id, obu->size);
     52 
     53    return len;
     54 }
     55 
     56 int ff_av1_packet_split(AV1Packet *pkt, const uint8_t *buf, int length, void *logctx)
     57 {
     58    GetByteContext bc;
     59    int consumed;
     60 
     61    bytestream2_init(&bc, buf, length);
     62    pkt->nb_obus = 0;
     63 
     64    while (bytestream2_get_bytes_left(&bc) > 0) {
     65        AV1OBU *obu;
     66 
     67        if (pkt->obus_allocated < pkt->nb_obus + 1) {
     68            int new_size = pkt->obus_allocated + 1;
     69            AV1OBU *tmp;
     70 
     71            if (new_size >= INT_MAX / sizeof(*tmp))
     72                return AVERROR(ENOMEM);
     73            tmp = av_fast_realloc(pkt->obus, &pkt->obus_allocated_size, new_size * sizeof(*tmp));
     74            if (!tmp)
     75                return AVERROR(ENOMEM);
     76 
     77            pkt->obus = tmp;
     78            memset(pkt->obus + pkt->obus_allocated, 0, sizeof(*pkt->obus));
     79            pkt->obus_allocated = new_size;
     80        }
     81        obu = &pkt->obus[pkt->nb_obus];
     82 
     83        consumed = ff_av1_extract_obu(obu, bc.buffer, bytestream2_get_bytes_left(&bc), logctx);
     84        if (consumed < 0)
     85            return consumed;
     86 
     87        bytestream2_skip(&bc, consumed);
     88 
     89        obu->size_bits = get_obu_bit_length(obu->data, obu->size, obu->type);
     90 
     91        if (obu->size_bits < 0 ||
     92            (obu->size_bits == 0 && (obu->type != AV1_OBU_TEMPORAL_DELIMITER &&
     93                                     obu->type != AV1_OBU_PADDING))) {
     94            av_log(logctx, AV_LOG_ERROR, "Invalid OBU of type %d, skipping.\n", obu->type);
     95            continue;
     96        }
     97 
     98        pkt->nb_obus++;
     99    }
    100 
    101    return 0;
    102 }
    103 
    104 void ff_av1_packet_uninit(AV1Packet *pkt)
    105 {
    106    av_freep(&pkt->obus);
    107    pkt->obus_allocated = pkt->obus_allocated_size = 0;
    108 }
    109 
    110 AVRational ff_av1_framerate(int64_t ticks_per_frame, int64_t units_per_tick,
    111                            int64_t time_scale)
    112 {
    113    AVRational fr;
    114 
    115    if (ticks_per_frame && units_per_tick && time_scale &&
    116        ticks_per_frame < INT64_MAX / units_per_tick    &&
    117        av_reduce(&fr.den, &fr.num, units_per_tick * ticks_per_frame,
    118                  time_scale, INT_MAX))
    119        return fr;
    120 
    121    return (AVRational){ 0, 1 };
    122 }