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jcapimin.c (10517B)


      1 /*
      2 * jcapimin.c
      3 *
      4 * This file was part of the Independent JPEG Group's software:
      5 * Copyright (C) 1994-1998, Thomas G. Lane.
      6 * Modified 2003-2010 by Guido Vollbeding.
      7 * libjpeg-turbo Modifications:
      8 * Copyright (C) 2022, D. R. Commander.
      9 * For conditions of distribution and use, see the accompanying README.ijg
     10 * file.
     11 *
     12 * This file contains application interface code for the compression half
     13 * of the JPEG library.  These are the "minimum" API routines that may be
     14 * needed in either the normal full-compression case or the transcoding-only
     15 * case.
     16 *
     17 * Most of the routines intended to be called directly by an application
     18 * are in this file or in jcapistd.c.  But also see jcparam.c for
     19 * parameter-setup helper routines, jcomapi.c for routines shared by
     20 * compression and decompression, and jctrans.c for the transcoding case.
     21 */
     22 
     23 #define JPEG_INTERNALS
     24 #include "jinclude.h"
     25 #include "jpeglib.h"
     26 #include "jcmaster.h"
     27 
     28 
     29 /*
     30 * Initialization of a JPEG compression object.
     31 * The error manager must already be set up (in case memory manager fails).
     32 */
     33 
     34 GLOBAL(void)
     35 jpeg_CreateCompress(j_compress_ptr cinfo, int version, size_t structsize)
     36 {
     37  int i;
     38 
     39  /* Guard against version mismatches between library and caller. */
     40  cinfo->mem = NULL;            /* so jpeg_destroy knows mem mgr not called */
     41  if (version != JPEG_LIB_VERSION)
     42    ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version);
     43  if (structsize != sizeof(struct jpeg_compress_struct))
     44    ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE,
     45             (int)sizeof(struct jpeg_compress_struct), (int)structsize);
     46 
     47  /* For debugging purposes, we zero the whole master structure.
     48   * But the application has already set the err pointer, and may have set
     49   * client_data, so we have to save and restore those fields.
     50   * Note: if application hasn't set client_data, tools like Purify may
     51   * complain here.
     52   */
     53  {
     54    struct jpeg_error_mgr *err = cinfo->err;
     55    void *client_data = cinfo->client_data; /* ignore Purify complaint here */
     56    memset(cinfo, 0, sizeof(struct jpeg_compress_struct));
     57    cinfo->err = err;
     58    cinfo->client_data = client_data;
     59  }
     60  cinfo->is_decompressor = FALSE;
     61 
     62  /* Initialize a memory manager instance for this object */
     63  jinit_memory_mgr((j_common_ptr)cinfo);
     64 
     65  /* Zero out pointers to permanent structures. */
     66  cinfo->progress = NULL;
     67  cinfo->dest = NULL;
     68 
     69  cinfo->comp_info = NULL;
     70 
     71  for (i = 0; i < NUM_QUANT_TBLS; i++) {
     72    cinfo->quant_tbl_ptrs[i] = NULL;
     73 #if JPEG_LIB_VERSION >= 70
     74    cinfo->q_scale_factor[i] = 100;
     75 #endif
     76  }
     77 
     78  for (i = 0; i < NUM_HUFF_TBLS; i++) {
     79    cinfo->dc_huff_tbl_ptrs[i] = NULL;
     80    cinfo->ac_huff_tbl_ptrs[i] = NULL;
     81  }
     82 
     83 #if JPEG_LIB_VERSION >= 80
     84  /* Must do it here for emit_dqt in case jpeg_write_tables is used */
     85  cinfo->block_size = DCTSIZE;
     86  cinfo->natural_order = jpeg_natural_order;
     87  cinfo->lim_Se = DCTSIZE2 - 1;
     88 #endif
     89 
     90  cinfo->script_space = NULL;
     91 
     92  cinfo->input_gamma = 1.0;     /* in case application forgets */
     93 
     94  cinfo->data_precision = BITS_IN_JSAMPLE;
     95 
     96  /* OK, I'm ready */
     97  cinfo->global_state = CSTATE_START;
     98 
     99  /* The master struct is used to store extension parameters, so we allocate it
    100   * here.
    101   */
    102  cinfo->master = (struct jpeg_comp_master *)
    103      (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_PERMANENT,
    104                                  sizeof(my_comp_master));
    105  memset(cinfo->master, 0, sizeof(my_comp_master));
    106 }
    107 
    108 
    109 /*
    110 * Destruction of a JPEG compression object
    111 */
    112 
    113 GLOBAL(void)
    114 jpeg_destroy_compress(j_compress_ptr cinfo)
    115 {
    116  jpeg_destroy((j_common_ptr)cinfo); /* use common routine */
    117 }
    118 
    119 
    120 /*
    121 * Abort processing of a JPEG compression operation,
    122 * but don't destroy the object itself.
    123 */
    124 
    125 GLOBAL(void)
    126 jpeg_abort_compress(j_compress_ptr cinfo)
    127 {
    128  jpeg_abort((j_common_ptr)cinfo); /* use common routine */
    129 }
    130 
    131 
    132 /*
    133 * Forcibly suppress or un-suppress all quantization and Huffman tables.
    134 * Marks all currently defined tables as already written (if suppress)
    135 * or not written (if !suppress).  This will control whether they get emitted
    136 * by a subsequent jpeg_start_compress call.
    137 *
    138 * This routine is exported for use by applications that want to produce
    139 * abbreviated JPEG datastreams.  It logically belongs in jcparam.c, but
    140 * since it is called by jpeg_start_compress, we put it here --- otherwise
    141 * jcparam.o would be linked whether the application used it or not.
    142 */
    143 
    144 GLOBAL(void)
    145 jpeg_suppress_tables(j_compress_ptr cinfo, boolean suppress)
    146 {
    147  int i;
    148  JQUANT_TBL *qtbl;
    149  JHUFF_TBL *htbl;
    150 
    151  for (i = 0; i < NUM_QUANT_TBLS; i++) {
    152    if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)
    153      qtbl->sent_table = suppress;
    154  }
    155 
    156  for (i = 0; i < NUM_HUFF_TBLS; i++) {
    157    if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)
    158      htbl->sent_table = suppress;
    159    if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)
    160      htbl->sent_table = suppress;
    161  }
    162 }
    163 
    164 
    165 /*
    166 * Finish JPEG compression.
    167 *
    168 * If a multipass operating mode was selected, this may do a great deal of
    169 * work including most of the actual output.
    170 */
    171 
    172 GLOBAL(void)
    173 jpeg_finish_compress(j_compress_ptr cinfo)
    174 {
    175  JDIMENSION iMCU_row;
    176 
    177  if (cinfo->global_state == CSTATE_SCANNING ||
    178      cinfo->global_state == CSTATE_RAW_OK) {
    179    /* Terminate first pass */
    180    if (cinfo->next_scanline < cinfo->image_height)
    181      ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
    182    (*cinfo->master->finish_pass) (cinfo);
    183  } else if (cinfo->global_state != CSTATE_WRCOEFS)
    184    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
    185  /* Perform any remaining passes */
    186  while (!cinfo->master->is_last_pass) {
    187    (*cinfo->master->prepare_for_pass) (cinfo);
    188    for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {
    189      if (cinfo->progress != NULL) {
    190        cinfo->progress->pass_counter = (long)iMCU_row;
    191        cinfo->progress->pass_limit = (long)cinfo->total_iMCU_rows;
    192        (*cinfo->progress->progress_monitor) ((j_common_ptr)cinfo);
    193      }
    194      /* We bypass the main controller and invoke coef controller directly;
    195       * all work is being done from the coefficient buffer.
    196       */
    197      if (cinfo->data_precision == 16) {
    198 #ifdef C_LOSSLESS_SUPPORTED
    199        if (!(*cinfo->coef->compress_data_16) (cinfo, (J16SAMPIMAGE)NULL))
    200          ERREXIT(cinfo, JERR_CANT_SUSPEND);
    201 #else
    202        ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
    203 #endif
    204      } else if (cinfo->data_precision == 12) {
    205        if (!(*cinfo->coef->compress_data_12) (cinfo, (J12SAMPIMAGE)NULL))
    206          ERREXIT(cinfo, JERR_CANT_SUSPEND);
    207      } else {
    208        if (!(*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE)NULL))
    209          ERREXIT(cinfo, JERR_CANT_SUSPEND);
    210      }
    211    }
    212    (*cinfo->master->finish_pass) (cinfo);
    213  }
    214  /* Write EOI, do final cleanup */
    215  (*cinfo->marker->write_file_trailer) (cinfo);
    216  (*cinfo->dest->term_destination) (cinfo);
    217  /* We can use jpeg_abort to release memory and reset global_state */
    218  jpeg_abort((j_common_ptr)cinfo);
    219 }
    220 
    221 
    222 /*
    223 * Write a special marker.
    224 * This is only recommended for writing COM or APPn markers.
    225 * Must be called after jpeg_start_compress() and before
    226 * first call to jpeg_write_scanlines() or jpeg_write_raw_data().
    227 */
    228 
    229 GLOBAL(void)
    230 jpeg_write_marker(j_compress_ptr cinfo, int marker, const JOCTET *dataptr,
    231                  unsigned int datalen)
    232 {
    233  void (*write_marker_byte) (j_compress_ptr info, int val);
    234 
    235  if (cinfo->next_scanline != 0 ||
    236      (cinfo->global_state != CSTATE_SCANNING &&
    237       cinfo->global_state != CSTATE_RAW_OK &&
    238       cinfo->global_state != CSTATE_WRCOEFS))
    239    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
    240 
    241  (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
    242  write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */
    243  while (datalen--) {
    244    (*write_marker_byte) (cinfo, *dataptr);
    245    dataptr++;
    246  }
    247 }
    248 
    249 /* Same, but piecemeal. */
    250 
    251 GLOBAL(void)
    252 jpeg_write_m_header(j_compress_ptr cinfo, int marker, unsigned int datalen)
    253 {
    254  if (cinfo->next_scanline != 0 ||
    255      (cinfo->global_state != CSTATE_SCANNING &&
    256       cinfo->global_state != CSTATE_RAW_OK &&
    257       cinfo->global_state != CSTATE_WRCOEFS))
    258    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
    259 
    260  (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
    261 }
    262 
    263 GLOBAL(void)
    264 jpeg_write_m_byte(j_compress_ptr cinfo, int val)
    265 {
    266  (*cinfo->marker->write_marker_byte) (cinfo, val);
    267 }
    268 
    269 
    270 /*
    271 * Alternate compression function: just write an abbreviated table file.
    272 * Before calling this, all parameters and a data destination must be set up.
    273 *
    274 * To produce a pair of files containing abbreviated tables and abbreviated
    275 * image data, one would proceed as follows:
    276 *
    277 *              initialize JPEG object
    278 *              set JPEG parameters
    279 *              set destination to table file
    280 *              jpeg_write_tables(cinfo);
    281 *              set destination to image file
    282 *              jpeg_start_compress(cinfo, FALSE);
    283 *              write data...
    284 *              jpeg_finish_compress(cinfo);
    285 *
    286 * jpeg_write_tables has the side effect of marking all tables written
    287 * (same as jpeg_suppress_tables(..., TRUE)).  Thus a subsequent start_compress
    288 * will not re-emit the tables unless it is passed write_all_tables=TRUE.
    289 */
    290 
    291 GLOBAL(void)
    292 jpeg_write_tables(j_compress_ptr cinfo)
    293 {
    294  if (cinfo->global_state != CSTATE_START)
    295    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
    296 
    297  /* (Re)initialize error mgr and destination modules */
    298  (*cinfo->err->reset_error_mgr) ((j_common_ptr)cinfo);
    299  (*cinfo->dest->init_destination) (cinfo);
    300  /* Initialize the marker writer ... bit of a crock to do it here. */
    301  jinit_marker_writer(cinfo);
    302  /* Write them tables! */
    303  (*cinfo->marker->write_tables_only) (cinfo);
    304  /* And clean up. */
    305  (*cinfo->dest->term_destination) (cinfo);
    306  /*
    307   * In library releases up through v6a, we called jpeg_abort() here to free
    308   * any working memory allocated by the destination manager and marker
    309   * writer.  Some applications had a problem with that: they allocated space
    310   * of their own from the library memory manager, and didn't want it to go
    311   * away during write_tables.  So now we do nothing.  This will cause a
    312   * memory leak if an app calls write_tables repeatedly without doing a full
    313   * compression cycle or otherwise resetting the JPEG object.  However, that
    314   * seems less bad than unexpectedly freeing memory in the normal case.
    315   * An app that prefers the old behavior can call jpeg_abort for itself after
    316   * each call to jpeg_write_tables().
    317   */
    318 }