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, 208 const JOCTET *dataptr, 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 } 296
