media/libjpeg/jcapimin.c

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