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