1 /* 2 * jpeglib.h 3 * 4 * Copyright (C) 1991-1998, Thomas G. Lane. 5 * This file is part of the Independent JPEG Group's software. 6 * For conditions of distribution and use, see the accompanying README file. 7 * 8 * This file defines the application interface for the JPEG library. 9 * Most applications using the library need only include this file, 10 * and perhaps jerror.h if they want to know the exact error codes. 11 */ 12 13 #ifndef JPEGLIB_H 14 #define JPEGLIB_H 15 16 /* 17 * First we include the configuration files that record how this 18 * installation of the JPEG library is set up. jconfig.h can be 19 * generated automatically for many systems. jmorecfg.h contains 20 * manual configuration options that most people need not worry about. 21 */ 22 23 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */ 24 #include "jconfig.h" /* widely used configuration options */ 25 #endif 26 #include "jmorecfg.h" /* seldom changed options */ 27 28 29 /* Version ID for the JPEG library. 30 * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60". 31 */ 32 33 #define JPEG_LIB_VERSION 62 /* Version 6b */ 34 35 36 /* Various constants determining the sizes of things. 37 * All of these are specified by the JPEG standard, so don't change them 38 * if you want to be compatible. 39 */ 40 41 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */ 42 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */ 43 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */ 44 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */ 45 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */ 46 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */ 47 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */ 48 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard; 49 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU. 50 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU 51 * to handle it. We even let you do this from the jconfig.h file. However, 52 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe 53 * sometimes emits noncompliant files doesn't mean you should too. 54 */ 55 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */ 56 #ifndef D_MAX_BLOCKS_IN_MCU 57 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */ 58 #endif 59 60 61 /* Data structures for images (arrays of samples and of DCT coefficients). 62 * On 80x86 machines, the image arrays are too big for near pointers, 63 * but the pointer arrays can fit in near memory. 64 */ 65 66 typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */ 67 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ 68 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ 69 70 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ 71 typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */ 72 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ 73 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ 74 75 typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */ 76 77 78 /* Types for JPEG compression parameters and working tables. */ 79 80 81 /* DCT coefficient quantization tables. */ 82 83 typedef struct { 84 /* This array gives the coefficient quantizers in natural array order 85 * (not the zigzag order in which they are stored in a JPEG DQT marker). 86 * CAUTION: IJG versions prior to v6a kept this array in zigzag order. 87 */ 88 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */ 89 /* This field is used only during compression. It's initialized FALSE when 90 * the table is created, and set TRUE when it's been output to the file. 91 * You could suppress output of a table by setting this to TRUE. 92 * (See jpeg_suppress_tables for an example.) 93 */ 94 boolean sent_table; /* TRUE when table has been output */ 95 } JQUANT_TBL; 96 97 98 /* Huffman coding tables. */ 99 100 typedef struct { 101 /* These two fields directly represent the contents of a JPEG DHT marker */ 102 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ 103 /* length k bits; bits[0] is unused */ 104 UINT8 huffval[256]; /* The symbols, in order of incr code length */ 105 /* This field is used only during compression. It's initialized FALSE when 106 * the table is created, and set TRUE when it's been output to the file. 107 * You could suppress output of a table by setting this to TRUE. 108 * (See jpeg_suppress_tables for an example.) 109 */ 110 boolean sent_table; /* TRUE when table has been output */ 111 } JHUFF_TBL; 112 113 114 /* Basic info about one component (color channel). */ 115 116 typedef struct { 117 /* These values are fixed over the whole image. */ 118 /* For compression, they must be supplied by parameter setup; */ 119 /* for decompression, they are read from the SOF marker. */ 120 int component_id; /* identifier for this component (0..255) */ 121 int component_index; /* its index in SOF or cinfo->comp_info[] */ 122 int h_samp_factor; /* horizontal sampling factor (1..4) */ 123 int v_samp_factor; /* vertical sampling factor (1..4) */ 124 int quant_tbl_no; /* quantization table selector (0..3) */ 125 /* These values may vary between scans. */ 126 /* For compression, they must be supplied by parameter setup; */ 127 /* for decompression, they are read from the SOS marker. */ 128 /* The decompressor output side may not use these variables. */ 129 int dc_tbl_no; /* DC entropy table selector (0..3) */ 130 int ac_tbl_no; /* AC entropy table selector (0..3) */ 131 132 /* Remaining fields should be treated as private by applications. */ 133 134 /* These values are computed during compression or decompression startup: */ 135 /* Component's size in DCT blocks. 136 * Any dummy blocks added to complete an MCU are not counted; therefore 137 * these values do not depend on whether a scan is interleaved or not. 138 */ 139 JDIMENSION width_in_blocks; 140 JDIMENSION height_in_blocks; 141 /* Size of a DCT block in samples. Always DCTSIZE for compression. 142 * For decompression this is the size of the output from one DCT block, 143 * reflecting any scaling we choose to apply during the IDCT step. 144 * Values of 1,2,4,8 are likely to be supported. Note that different 145 * components may receive different IDCT scalings. 146 */ 147 int DCT_scaled_size; 148 /* The downsampled dimensions are the component's actual, unpadded number 149 * of samples at the main buffer (preprocessing/compression interface), thus 150 * downsampled_width = ceil(image_width * Hi/Hmax) 151 * and similarly for height. For decompression, IDCT scaling is included, so 152 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE) 153 */ 154 JDIMENSION downsampled_width; /* actual width in samples */ 155 JDIMENSION downsampled_height; /* actual height in samples */ 156 /* This flag is used only for decompression. In cases where some of the 157 * components will be ignored (eg grayscale output from YCbCr image), 158 * we can skip most computations for the unused components. 159 */ 160 boolean component_needed; /* do we need the value of this component? */ 161 162 /* These values are computed before starting a scan of the component. */ 163 /* The decompressor output side may not use these variables. */ 164 int MCU_width; /* number of blocks per MCU, horizontally */ 165 int MCU_height; /* number of blocks per MCU, vertically */ 166 int MCU_blocks; /* MCU_width * MCU_height */ 167 int MCU_sample_width; /* MCU width in samples, MCU_width*DCT_scaled_size */ 168 int last_col_width; /* # of non-dummy blocks across in last MCU */ 169 int last_row_height; /* # of non-dummy blocks down in last MCU */ 170 171 /* Saved quantization table for component; NULL if none yet saved. 172 * See jdinput.c comments about the need for this information. 173 * This field is currently used only for decompression. 174 */ 175 JQUANT_TBL * quant_table; 176 177 /* Private per-component storage for DCT or IDCT subsystem. */ 178 void * dct_table; 179 } jpeg_component_info; 180 181 182 /* The script for encoding a multiple-scan file is an array of these: */ 183 184 typedef struct { 185 int comps_in_scan; /* number of components encoded in this scan */ 186 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */ 187 int Ss, Se; /* progressive JPEG spectral selection parms */ 188 int Ah, Al; /* progressive JPEG successive approx. parms */ 189 } jpeg_scan_info; 190 191 /* The decompressor can save APPn and COM markers in a list of these: */ 192 193 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr; 194 195 struct jpeg_marker_struct { 196 jpeg_saved_marker_ptr next; /* next in list, or NULL */ 197 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */ 198 unsigned int original_length; /* # bytes of data in the file */ 199 unsigned int data_length; /* # bytes of data saved at data[] */ 200 JOCTET FAR * data; /* the data contained in the marker */ 201 /* the marker length word is not counted in data_length or original_length */ 202 }; 203 204 /* Known color spaces. */ 205 206 typedef enum { 207 JCS_UNKNOWN, /* error/unspecified */ 208 JCS_GRAYSCALE, /* monochrome */ 209 JCS_RGB, /* red/green/blue */ 210 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ 211 JCS_CMYK, /* C/M/Y/K */ 212 JCS_YCCK, /* Y/Cb/Cr/K */ 213 #ifdef ANDROID_RGB 214 JCS_RGBA_8888, /* red/green/blue/alpha */ 215 JCS_RGB_565 /* red/green/blue in 565 format */ 216 #endif 217 } J_COLOR_SPACE; 218 219 /* DCT/IDCT algorithm options. */ 220 221 typedef enum { 222 JDCT_ISLOW, /* slow but accurate integer algorithm */ 223 JDCT_IFAST, /* faster, less accurate integer method */ 224 JDCT_FLOAT /* floating-point: accurate, fast on fast HW */ 225 } J_DCT_METHOD; 226 227 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */ 228 #define JDCT_DEFAULT JDCT_ISLOW 229 #endif 230 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */ 231 #define JDCT_FASTEST JDCT_IFAST 232 #endif 233 234 /* Dithering options for decompression. */ 235 236 typedef enum { 237 JDITHER_NONE, /* no dithering */ 238 JDITHER_ORDERED, /* simple ordered dither */ 239 JDITHER_FS /* Floyd-Steinberg error diffusion dither */ 240 } J_DITHER_MODE; 241 242 243 /* Common fields between JPEG compression and decompression master structs. */ 244 245 #define jpeg_common_fields \ 246 struct jpeg_error_mgr * err; /* Error handler module */\ 247 struct jpeg_memory_mgr * mem; /* Memory manager module */\ 248 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\ 249 void * client_data; /* Available for use by application */\ 250 boolean is_decompressor; /* So common code can tell which is which */\ 251 int global_state /* For checking call sequence validity */ 252 253 /* Routines that are to be used by both halves of the library are declared 254 * to receive a pointer to this structure. There are no actual instances of 255 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct. 256 */ 257 struct jpeg_common_struct { 258 jpeg_common_fields; /* Fields common to both master struct types */ 259 /* Additional fields follow in an actual jpeg_compress_struct or 260 * jpeg_decompress_struct. All three structs must agree on these 261 * initial fields! (This would be a lot cleaner in C++.) 262 */ 263 }; 264 265 typedef struct jpeg_common_struct * j_common_ptr; 266 typedef struct jpeg_compress_struct * j_compress_ptr; 267 typedef struct jpeg_decompress_struct * j_decompress_ptr; 268 269 270 /* Master record for a compression instance */ 271 272 struct jpeg_compress_struct { 273 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */ 274 275 /* Destination for compressed data */ 276 struct jpeg_destination_mgr * dest; 277 278 /* Description of source image --- these fields must be filled in by 279 * outer application before starting compression. in_color_space must 280 * be correct before you can even call jpeg_set_defaults(). 281 */ 282 283 JDIMENSION image_width; /* input image width */ 284 JDIMENSION image_height; /* input image height */ 285 int input_components; /* # of color components in input image */ 286 J_COLOR_SPACE in_color_space; /* colorspace of input image */ 287 288 double input_gamma; /* image gamma of input image */ 289 290 /* Compression parameters --- these fields must be set before calling 291 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to 292 * initialize everything to reasonable defaults, then changing anything 293 * the application specifically wants to change. That way you won't get 294 * burnt when new parameters are added. Also note that there are several 295 * helper routines to simplify changing parameters. 296 */ 297 298 int data_precision; /* bits of precision in image data */ 299 300 int num_components; /* # of color components in JPEG image */ 301 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 302 303 jpeg_component_info * comp_info; 304 /* comp_info[i] describes component that appears i'th in SOF */ 305 306 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 307 /* ptrs to coefficient quantization tables, or NULL if not defined */ 308 309 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 310 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 311 /* ptrs to Huffman coding tables, or NULL if not defined */ 312 313 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 314 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 315 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 316 317 int num_scans; /* # of entries in scan_info array */ 318 const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */ 319 /* The default value of scan_info is NULL, which causes a single-scan 320 * sequential JPEG file to be emitted. To create a multi-scan file, 321 * set num_scans and scan_info to point to an array of scan definitions. 322 */ 323 324 boolean raw_data_in; /* TRUE=caller supplies downsampled data */ 325 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 326 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ 327 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 328 int smoothing_factor; /* 1..100, or 0 for no input smoothing */ 329 J_DCT_METHOD dct_method; /* DCT algorithm selector */ 330 331 /* The restart interval can be specified in absolute MCUs by setting 332 * restart_interval, or in MCU rows by setting restart_in_rows 333 * (in which case the correct restart_interval will be figured 334 * for each scan). 335 */ 336 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */ 337 int restart_in_rows; /* if > 0, MCU rows per restart interval */ 338 339 /* Parameters controlling emission of special markers. */ 340 341 boolean write_JFIF_header; /* should a JFIF marker be written? */ 342 UINT8 JFIF_major_version; /* What to write for the JFIF version number */ 343 UINT8 JFIF_minor_version; 344 /* These three values are not used by the JPEG code, merely copied */ 345 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ 346 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ 347 /* ratio is defined by X_density/Y_density even when density_unit=0. */ 348 UINT8 density_unit; /* JFIF code for pixel size units */ 349 UINT16 X_density; /* Horizontal pixel density */ 350 UINT16 Y_density; /* Vertical pixel density */ 351 boolean write_Adobe_marker; /* should an Adobe marker be written? */ 352 353 /* State variable: index of next scanline to be written to 354 * jpeg_write_scanlines(). Application may use this to control its 355 * processing loop, e.g., "while (next_scanline < image_height)". 356 */ 357 358 JDIMENSION next_scanline; /* 0 .. image_height-1 */ 359 360 /* Remaining fields are known throughout compressor, but generally 361 * should not be touched by a surrounding application. 362 */ 363 364 /* 365 * These fields are computed during compression startup 366 */ 367 boolean progressive_mode; /* TRUE if scan script uses progressive mode */ 368 int max_h_samp_factor; /* largest h_samp_factor */ 369 int max_v_samp_factor; /* largest v_samp_factor */ 370 371 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */ 372 /* The coefficient controller receives data in units of MCU rows as defined 373 * for fully interleaved scans (whether the JPEG file is interleaved or not). 374 * There are v_samp_factor * DCTSIZE sample rows of each component in an 375 * "iMCU" (interleaved MCU) row. 376 */ 377 378 /* 379 * These fields are valid during any one scan. 380 * They describe the components and MCUs actually appearing in the scan. 381 */ 382 int comps_in_scan; /* # of JPEG components in this scan */ 383 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 384 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 385 386 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 387 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 388 389 int blocks_in_MCU; /* # of DCT blocks per MCU */ 390 int MCU_membership[C_MAX_BLOCKS_IN_MCU]; 391 /* MCU_membership[i] is index in cur_comp_info of component owning */ 392 /* i'th block in an MCU */ 393 394 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */ 395 396 /* 397 * Links to compression subobjects (methods and private variables of modules) 398 */ 399 struct jpeg_comp_master * master; 400 struct jpeg_c_main_controller * main; 401 struct jpeg_c_prep_controller * prep; 402 struct jpeg_c_coef_controller * coef; 403 struct jpeg_marker_writer * marker; 404 struct jpeg_color_converter * cconvert; 405 struct jpeg_downsampler * downsample; 406 struct jpeg_forward_dct * fdct; 407 struct jpeg_entropy_encoder * entropy; 408 jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */ 409 int script_space_size; 410 }; 411 412 413 /* Master record for a decompression instance */ 414 415 struct jpeg_decompress_struct { 416 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */ 417 418 /* Source of compressed data */ 419 struct jpeg_source_mgr * src; 420 421 /* Basic description of image --- filled in by jpeg_read_header(). */ 422 /* Application may inspect these values to decide how to process image. */ 423 424 JDIMENSION image_width; /* nominal image width (from SOF marker) */ 425 JDIMENSION image_height; /* nominal image height */ 426 int num_components; /* # of color components in JPEG image */ 427 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 428 429 /* Decompression processing parameters --- these fields must be set before 430 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes 431 * them to default values. 432 */ 433 434 J_COLOR_SPACE out_color_space; /* colorspace for output */ 435 436 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 437 438 double output_gamma; /* image gamma wanted in output */ 439 440 boolean buffered_image; /* TRUE=multiple output passes */ 441 boolean raw_data_out; /* TRUE=downsampled data wanted */ 442 443 J_DCT_METHOD dct_method; /* IDCT algorithm selector */ 444 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */ 445 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */ 446 447 boolean quantize_colors; /* TRUE=colormapped output wanted */ 448 /* the following are ignored if not quantize_colors: */ 449 J_DITHER_MODE dither_mode; /* type of color dithering to use */ 450 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */ 451 int desired_number_of_colors; /* max # colors to use in created colormap */ 452 /* these are significant only in buffered-image mode: */ 453 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */ 454 boolean enable_external_quant;/* enable future use of external colormap */ 455 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */ 456 457 /* Description of actual output image that will be returned to application. 458 * These fields are computed by jpeg_start_decompress(). 459 * You can also use jpeg_calc_output_dimensions() to determine these values 460 * in advance of calling jpeg_start_decompress(). 461 */ 462 463 JDIMENSION output_width; /* scaled image width */ 464 JDIMENSION output_height; /* scaled image height */ 465 int out_color_components; /* # of color components in out_color_space */ 466 int output_components; /* # of color components returned */ 467 /* output_components is 1 (a colormap index) when quantizing colors; 468 * otherwise it equals out_color_components. 469 */ 470 int rec_outbuf_height; /* min recommended height of scanline buffer */ 471 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows 472 * high, space and time will be wasted due to unnecessary data copying. 473 * Usually rec_outbuf_height will be 1 or 2, at most 4. 474 */ 475 476 /* When quantizing colors, the output colormap is described by these fields. 477 * The application can supply a colormap by setting colormap non-NULL before 478 * calling jpeg_start_decompress; otherwise a colormap is created during 479 * jpeg_start_decompress or jpeg_start_output. 480 * The map has out_color_components rows and actual_number_of_colors columns. 481 */ 482 int actual_number_of_colors; /* number of entries in use */ 483 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */ 484 485 /* State variables: these variables indicate the progress of decompression. 486 * The application may examine these but must not modify them. 487 */ 488 489 /* Row index of next scanline to be read from jpeg_read_scanlines(). 490 * Application may use this to control its processing loop, e.g., 491 * "while (output_scanline < output_height)". 492 */ 493 JDIMENSION output_scanline; /* 0 .. output_height-1 */ 494 495 /* Current input scan number and number of iMCU rows completed in scan. 496 * These indicate the progress of the decompressor input side. 497 */ 498 int input_scan_number; /* Number of SOS markers seen so far */ 499 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */ 500 501 /* The "output scan number" is the notional scan being displayed by the 502 * output side. The decompressor will not allow output scan/row number 503 * to get ahead of input scan/row, but it can fall arbitrarily far behind. 504 */ 505 int output_scan_number; /* Nominal scan number being displayed */ 506 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */ 507 508 /* Current progression status. coef_bits[c][i] indicates the precision 509 * with which component c's DCT coefficient i (in zigzag order) is known. 510 * It is -1 when no data has yet been received, otherwise it is the point 511 * transform (shift) value for the most recent scan of the coefficient 512 * (thus, 0 at completion of the progression). 513 * This pointer is NULL when reading a non-progressive file. 514 */ 515 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */ 516 517 /* Internal JPEG parameters --- the application usually need not look at 518 * these fields. Note that the decompressor output side may not use 519 * any parameters that can change between scans. 520 */ 521 522 /* Quantization and Huffman tables are carried forward across input 523 * datastreams when processing abbreviated JPEG datastreams. 524 */ 525 526 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 527 /* ptrs to coefficient quantization tables, or NULL if not defined */ 528 529 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 530 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 531 /* ptrs to Huffman coding tables, or NULL if not defined */ 532 533 /* These parameters are never carried across datastreams, since they 534 * are given in SOF/SOS markers or defined to be reset by SOI. 535 */ 536 537 int data_precision; /* bits of precision in image data */ 538 539 jpeg_component_info * comp_info; 540 /* comp_info[i] describes component that appears i'th in SOF */ 541 542 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */ 543 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 544 545 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 546 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 547 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 548 549 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */ 550 551 /* These fields record data obtained from optional markers recognized by 552 * the JPEG library. 553 */ 554 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */ 555 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */ 556 UINT8 JFIF_major_version; /* JFIF version number */ 557 UINT8 JFIF_minor_version; 558 UINT8 density_unit; /* JFIF code for pixel size units */ 559 UINT16 X_density; /* Horizontal pixel density */ 560 UINT16 Y_density; /* Vertical pixel density */ 561 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */ 562 UINT8 Adobe_transform; /* Color transform code from Adobe marker */ 563 564 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 565 566 /* Aside from the specific data retained from APPn markers known to the 567 * library, the uninterpreted contents of any or all APPn and COM markers 568 * can be saved in a list for examination by the application. 569 */ 570 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */ 571 572 /* Remaining fields are known throughout decompressor, but generally 573 * should not be touched by a surrounding application. 574 */ 575 576 /* 577 * These fields are computed during decompression startup 578 */ 579 int max_h_samp_factor; /* largest h_samp_factor */ 580 int max_v_samp_factor; /* largest v_samp_factor */ 581 582 int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */ 583 584 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ 585 /* The coefficient controller's input and output progress is measured in 586 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows 587 * in fully interleaved JPEG scans, but are used whether the scan is 588 * interleaved or not. We define an iMCU row as v_samp_factor DCT block 589 * rows of each component. Therefore, the IDCT output contains 590 * v_samp_factor*DCT_scaled_size sample rows of a component per iMCU row. 591 */ 592 593 JSAMPLE * sample_range_limit; /* table for fast range-limiting */ 594 595 /* 596 * These fields are valid during any one scan. 597 * They describe the components and MCUs actually appearing in the scan. 598 * Note that the decompressor output side must not use these fields. 599 */ 600 int comps_in_scan; /* # of JPEG components in this scan */ 601 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 602 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 603 604 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 605 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 606 607 int blocks_in_MCU; /* # of DCT blocks per MCU */ 608 int MCU_membership[D_MAX_BLOCKS_IN_MCU]; 609 /* MCU_membership[i] is index in cur_comp_info of component owning */ 610 /* i'th block in an MCU */ 611 612 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */ 613 614 /* This field is shared between entropy decoder and marker parser. 615 * It is either zero or the code of a JPEG marker that has been 616 * read from the data source, but has not yet been processed. 617 */ 618 int unread_marker; 619 620 /* 621 * Links to decompression subobjects (methods, private variables of modules) 622 */ 623 struct jpeg_decomp_master * master; 624 struct jpeg_d_main_controller * main; 625 struct jpeg_d_coef_controller * coef; 626 struct jpeg_d_post_controller * post; 627 struct jpeg_input_controller * inputctl; 628 struct jpeg_marker_reader * marker; 629 struct jpeg_entropy_decoder * entropy; 630 struct jpeg_inverse_dct * idct; 631 struct jpeg_upsampler * upsample; 632 struct jpeg_color_deconverter * cconvert; 633 struct jpeg_color_quantizer * cquantize; 634 }; 635 636 637 /* "Object" declarations for JPEG modules that may be supplied or called 638 * directly by the surrounding application. 639 * As with all objects in the JPEG library, these structs only define the 640 * publicly visible methods and state variables of a module. Additional 641 * private fields may exist after the public ones. 642 */ 643 644 645 /* Error handler object */ 646 647 struct jpeg_error_mgr { 648 /* Error exit handler: does not return to caller */ 649 JMETHOD(void, error_exit, (j_common_ptr cinfo)); 650 /* Conditionally emit a trace or warning message */ 651 JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level)); 652 /* Routine that actually outputs a trace or error message */ 653 JMETHOD(void, output_message, (j_common_ptr cinfo)); 654 /* Format a message string for the most recent JPEG error or message */ 655 JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer)); 656 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */ 657 /* Reset error state variables at start of a new image */ 658 JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo)); 659 660 /* The message ID code and any parameters are saved here. 661 * A message can have one string parameter or up to 8 int parameters. 662 */ 663 int msg_code; 664 #define JMSG_STR_PARM_MAX 80 665 union { 666 int i[8]; 667 char s[JMSG_STR_PARM_MAX]; 668 } msg_parm; 669 670 /* Standard state variables for error facility */ 671 672 int trace_level; /* max msg_level that will be displayed */ 673 674 /* For recoverable corrupt-data errors, we emit a warning message, 675 * but keep going unless emit_message chooses to abort. emit_message 676 * should count warnings in num_warnings. The surrounding application 677 * can check for bad data by seeing if num_warnings is nonzero at the 678 * end of processing. 679 */ 680 long num_warnings; /* number of corrupt-data warnings */ 681 682 /* These fields point to the table(s) of error message strings. 683 * An application can change the table pointer to switch to a different 684 * message list (typically, to change the language in which errors are 685 * reported). Some applications may wish to add additional error codes 686 * that will be handled by the JPEG library error mechanism; the second 687 * table pointer is used for this purpose. 688 * 689 * First table includes all errors generated by JPEG library itself. 690 * Error code 0 is reserved for a "no such error string" message. 691 */ 692 const char * const * jpeg_message_table; /* Library errors */ 693 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */ 694 /* Second table can be added by application (see cjpeg/djpeg for example). 695 * It contains strings numbered first_addon_message..last_addon_message. 696 */ 697 const char * const * addon_message_table; /* Non-library errors */ 698 int first_addon_message; /* code for first string in addon table */ 699 int last_addon_message; /* code for last string in addon table */ 700 }; 701 702 703 /* Progress monitor object */ 704 705 struct jpeg_progress_mgr { 706 JMETHOD(void, progress_monitor, (j_common_ptr cinfo)); 707 708 long pass_counter; /* work units completed in this pass */ 709 long pass_limit; /* total number of work units in this pass */ 710 int completed_passes; /* passes completed so far */ 711 int total_passes; /* total number of passes expected */ 712 }; 713 714 715 /* Data destination object for compression */ 716 717 struct jpeg_destination_mgr { 718 JOCTET * next_output_byte; /* => next byte to write in buffer */ 719 size_t free_in_buffer; /* # of byte spaces remaining in buffer */ 720 721 JMETHOD(void, init_destination, (j_compress_ptr cinfo)); 722 JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo)); 723 JMETHOD(void, term_destination, (j_compress_ptr cinfo)); 724 }; 725 726 727 /* Data source object for decompression */ 728 729 struct jpeg_source_mgr { 730 const JOCTET * next_input_byte; /* => next byte to read from buffer */ 731 size_t bytes_in_buffer; /* # of bytes remaining in buffer */ 732 733 JMETHOD(void, init_source, (j_decompress_ptr cinfo)); 734 JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo)); 735 JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes)); 736 JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired)); 737 JMETHOD(void, term_source, (j_decompress_ptr cinfo)); 738 }; 739 740 741 /* Memory manager object. 742 * Allocates "small" objects (a few K total), "large" objects (tens of K), 743 * and "really big" objects (virtual arrays with backing store if needed). 744 * The memory manager does not allow individual objects to be freed; rather, 745 * each created object is assigned to a pool, and whole pools can be freed 746 * at once. This is faster and more convenient than remembering exactly what 747 * to free, especially where malloc()/free() are not too speedy. 748 * NB: alloc routines never return NULL. They exit to error_exit if not 749 * successful. 750 */ 751 752 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */ 753 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */ 754 #define JPOOL_NUMPOOLS 2 755 756 typedef struct jvirt_sarray_control * jvirt_sarray_ptr; 757 typedef struct jvirt_barray_control * jvirt_barray_ptr; 758 759 760 struct jpeg_memory_mgr { 761 /* Method pointers */ 762 JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id, 763 size_t sizeofobject)); 764 JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id, 765 size_t sizeofobject)); 766 JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id, 767 JDIMENSION samplesperrow, 768 JDIMENSION numrows)); 769 JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id, 770 JDIMENSION blocksperrow, 771 JDIMENSION numrows)); 772 JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo, 773 int pool_id, 774 boolean pre_zero, 775 JDIMENSION samplesperrow, 776 JDIMENSION numrows, 777 JDIMENSION maxaccess)); 778 JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo, 779 int pool_id, 780 boolean pre_zero, 781 JDIMENSION blocksperrow, 782 JDIMENSION numrows, 783 JDIMENSION maxaccess)); 784 JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo)); 785 JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo, 786 jvirt_sarray_ptr ptr, 787 JDIMENSION start_row, 788 JDIMENSION num_rows, 789 boolean writable)); 790 JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo, 791 jvirt_barray_ptr ptr, 792 JDIMENSION start_row, 793 JDIMENSION num_rows, 794 boolean writable)); 795 JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id)); 796 JMETHOD(void, self_destruct, (j_common_ptr cinfo)); 797 798 /* Limit on memory allocation for this JPEG object. (Note that this is 799 * merely advisory, not a guaranteed maximum; it only affects the space 800 * used for virtual-array buffers.) May be changed by outer application 801 * after creating the JPEG object. 802 */ 803 long max_memory_to_use; 804 805 /* Maximum allocation request accepted by alloc_large. */ 806 long max_alloc_chunk; 807 }; 808 809 810 /* Routine signature for application-supplied marker processing methods. 811 * Need not pass marker code since it is stored in cinfo->unread_marker. 812 */ 813 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo)); 814 815 816 /* Declarations for routines called by application. 817 * The JPP macro hides prototype parameters from compilers that can't cope. 818 * Note JPP requires double parentheses. 819 */ 820 821 #ifdef HAVE_PROTOTYPES 822 #define JPP(arglist) arglist 823 #else 824 #define JPP(arglist) () 825 #endif 826 827 828 /* Short forms of external names for systems with brain-damaged linkers. 829 * We shorten external names to be unique in the first six letters, which 830 * is good enough for all known systems. 831 * (If your compiler itself needs names to be unique in less than 15 832 * characters, you are out of luck. Get a better compiler.) 833 */ 834 835 #ifdef NEED_SHORT_EXTERNAL_NAMES 836 #define jpeg_std_error jStdError 837 #define jpeg_CreateCompress jCreaCompress 838 #define jpeg_CreateDecompress jCreaDecompress 839 #define jpeg_destroy_compress jDestCompress 840 #define jpeg_destroy_decompress jDestDecompress 841 #define jpeg_stdio_dest jStdDest 842 #define jpeg_stdio_src jStdSrc 843 #define jpeg_set_defaults jSetDefaults 844 #define jpeg_set_colorspace jSetColorspace 845 #define jpeg_default_colorspace jDefColorspace 846 #define jpeg_set_quality jSetQuality 847 #define jpeg_set_linear_quality jSetLQuality 848 #define jpeg_add_quant_table jAddQuantTable 849 #define jpeg_quality_scaling jQualityScaling 850 #define jpeg_simple_progression jSimProgress 851 #define jpeg_suppress_tables jSuppressTables 852 #define jpeg_alloc_quant_table jAlcQTable 853 #define jpeg_alloc_huff_table jAlcHTable 854 #define jpeg_start_compress jStrtCompress 855 #define jpeg_write_scanlines jWrtScanlines 856 #define jpeg_finish_compress jFinCompress 857 #define jpeg_write_raw_data jWrtRawData 858 #define jpeg_write_marker jWrtMarker 859 #define jpeg_write_m_header jWrtMHeader 860 #define jpeg_write_m_byte jWrtMByte 861 #define jpeg_write_tables jWrtTables 862 #define jpeg_read_header jReadHeader 863 #define jpeg_start_decompress jStrtDecompress 864 #define jpeg_read_scanlines jReadScanlines 865 #define jpeg_finish_decompress jFinDecompress 866 #define jpeg_read_raw_data jReadRawData 867 #define jpeg_has_multiple_scans jHasMultScn 868 #define jpeg_start_output jStrtOutput 869 #define jpeg_finish_output jFinOutput 870 #define jpeg_input_complete jInComplete 871 #define jpeg_new_colormap jNewCMap 872 #define jpeg_consume_input jConsumeInput 873 #define jpeg_calc_output_dimensions jCalcDimensions 874 #define jpeg_save_markers jSaveMarkers 875 #define jpeg_set_marker_processor jSetMarker 876 #define jpeg_read_coefficients jReadCoefs 877 #define jpeg_write_coefficients jWrtCoefs 878 #define jpeg_copy_critical_parameters jCopyCrit 879 #define jpeg_abort_compress jAbrtCompress 880 #define jpeg_abort_decompress jAbrtDecompress 881 #define jpeg_abort jAbort 882 #define jpeg_destroy jDestroy 883 #define jpeg_resync_to_restart jResyncRestart 884 #endif /* NEED_SHORT_EXTERNAL_NAMES */ 885 886 887 /* Default error-management setup */ 888 EXTERN(struct jpeg_error_mgr *) jpeg_std_error 889 JPP((struct jpeg_error_mgr * err)); 890 891 /* Initialization of JPEG compression objects. 892 * jpeg_create_compress() and jpeg_create_decompress() are the exported 893 * names that applications should call. These expand to calls on 894 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information 895 * passed for version mismatch checking. 896 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx. 897 */ 898 #define jpeg_create_compress(cinfo) \ 899 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \ 900 (size_t) sizeof(struct jpeg_compress_struct)) 901 #define jpeg_create_decompress(cinfo) \ 902 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \ 903 (size_t) sizeof(struct jpeg_decompress_struct)) 904 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo, 905 int version, size_t structsize)); 906 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo, 907 int version, size_t structsize)); 908 /* Destruction of JPEG compression objects */ 909 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo)); 910 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo)); 911 912 /* Standard data source and destination managers: stdio streams. */ 913 /* Caller is responsible for opening the file before and closing after. */ 914 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile)); 915 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile)); 916 917 /* Default parameter setup for compression */ 918 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo)); 919 /* Compression parameter setup aids */ 920 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo, 921 J_COLOR_SPACE colorspace)); 922 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo)); 923 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality, 924 boolean force_baseline)); 925 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo, 926 int scale_factor, 927 boolean force_baseline)); 928 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl, 929 const unsigned int *basic_table, 930 int scale_factor, 931 boolean force_baseline)); 932 EXTERN(int) jpeg_quality_scaling JPP((int quality)); 933 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo)); 934 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo, 935 boolean suppress)); 936 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo)); 937 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo)); 938 939 /* Main entry points for compression */ 940 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo, 941 boolean write_all_tables)); 942 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo, 943 JSAMPARRAY scanlines, 944 JDIMENSION num_lines)); 945 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo)); 946 947 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */ 948 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo, 949 JSAMPIMAGE data, 950 JDIMENSION num_lines)); 951 952 /* Write a special marker. See libjpeg.doc concerning safe usage. */ 953 EXTERN(void) jpeg_write_marker 954 JPP((j_compress_ptr cinfo, int marker, 955 const JOCTET * dataptr, unsigned int datalen)); 956 /* Same, but piecemeal. */ 957 EXTERN(void) jpeg_write_m_header 958 JPP((j_compress_ptr cinfo, int marker, unsigned int datalen)); 959 EXTERN(void) jpeg_write_m_byte 960 JPP((j_compress_ptr cinfo, int val)); 961 962 /* Alternate compression function: just write an abbreviated table file */ 963 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo)); 964 965 /* Decompression startup: read start of JPEG datastream to see what's there */ 966 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo, 967 boolean require_image)); 968 /* Return value is one of: */ 969 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */ 970 #define JPEG_HEADER_OK 1 /* Found valid image datastream */ 971 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */ 972 /* If you pass require_image = TRUE (normal case), you need not check for 973 * a TABLES_ONLY return code; an abbreviated file will cause an error exit. 974 * JPEG_SUSPENDED is only possible if you use a data source module that can 975 * give a suspension return (the stdio source module doesn't). 976 */ 977 978 /* Main entry points for decompression */ 979 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo)); 980 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo, 981 JSAMPARRAY scanlines, 982 JDIMENSION max_lines)); 983 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo)); 984 985 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */ 986 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo, 987 JSAMPIMAGE data, 988 JDIMENSION max_lines)); 989 990 /* Additional entry points for buffered-image mode. */ 991 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo)); 992 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo, 993 int scan_number)); 994 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo)); 995 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo)); 996 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo)); 997 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo)); 998 /* Return value is one of: */ 999 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */ 1000 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */ 1001 #define JPEG_REACHED_EOI 2 /* Reached end of image */ 1002 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */ 1003 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */ 1004 1005 /* Precalculate output dimensions for current decompression parameters. */ 1006 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo)); 1007 1008 /* Control saving of COM and APPn markers into marker_list. */ 1009 EXTERN(void) jpeg_save_markers 1010 JPP((j_decompress_ptr cinfo, int marker_code, 1011 unsigned int length_limit)); 1012 1013 /* Install a special processing method for COM or APPn markers. */ 1014 EXTERN(void) jpeg_set_marker_processor 1015 JPP((j_decompress_ptr cinfo, int marker_code, 1016 jpeg_marker_parser_method routine)); 1017 1018 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */ 1019 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo)); 1020 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo, 1021 jvirt_barray_ptr * coef_arrays)); 1022 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo, 1023 j_compress_ptr dstinfo)); 1024 1025 /* If you choose to abort compression or decompression before completing 1026 * jpeg_finish_(de)compress, then you need to clean up to release memory, 1027 * temporary files, etc. You can just call jpeg_destroy_(de)compress 1028 * if you're done with the JPEG object, but if you want to clean it up and 1029 * reuse it, call this: 1030 */ 1031 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo)); 1032 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo)); 1033 1034 /* Generic versions of jpeg_abort and jpeg_destroy that work on either 1035 * flavor of JPEG object. These may be more convenient in some places. 1036 */ 1037 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo)); 1038 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo)); 1039 1040 /* Default restart-marker-resync procedure for use by data source modules */ 1041 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo, 1042 int desired)); 1043 1044 1045 /* These marker codes are exported since applications and data source modules 1046 * are likely to want to use them. 1047 */ 1048 1049 #define JPEG_RST0 0xD0 /* RST0 marker code */ 1050 #define JPEG_EOI 0xD9 /* EOI marker code */ 1051 #define JPEG_APP0 0xE0 /* APP0 marker code */ 1052 #define JPEG_COM 0xFE /* COM marker code */ 1053 1054 1055 /* If we have a brain-damaged compiler that emits warnings (or worse, errors) 1056 * for structure definitions that are never filled in, keep it quiet by 1057 * supplying dummy definitions for the various substructures. 1058 */ 1059 1060 #ifdef INCOMPLETE_TYPES_BROKEN 1061 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */ 1062 struct jvirt_sarray_control { long dummy; }; 1063 struct jvirt_barray_control { long dummy; }; 1064 struct jpeg_comp_master { long dummy; }; 1065 struct jpeg_c_main_controller { long dummy; }; 1066 struct jpeg_c_prep_controller { long dummy; }; 1067 struct jpeg_c_coef_controller { long dummy; }; 1068 struct jpeg_marker_writer { long dummy; }; 1069 struct jpeg_color_converter { long dummy; }; 1070 struct jpeg_downsampler { long dummy; }; 1071 struct jpeg_forward_dct { long dummy; }; 1072 struct jpeg_entropy_encoder { long dummy; }; 1073 struct jpeg_decomp_master { long dummy; }; 1074 struct jpeg_d_main_controller { long dummy; }; 1075 struct jpeg_d_coef_controller { long dummy; }; 1076 struct jpeg_d_post_controller { long dummy; }; 1077 struct jpeg_input_controller { long dummy; }; 1078 struct jpeg_marker_reader { long dummy; }; 1079 struct jpeg_entropy_decoder { long dummy; }; 1080 struct jpeg_inverse_dct { long dummy; }; 1081 struct jpeg_upsampler { long dummy; }; 1082 struct jpeg_color_deconverter { long dummy; }; 1083 struct jpeg_color_quantizer { long dummy; }; 1084 #endif /* JPEG_INTERNALS */ 1085 #endif /* INCOMPLETE_TYPES_BROKEN */ 1086 1087 1088 /* 1089 * The JPEG library modules define JPEG_INTERNALS before including this file. 1090 * The internal structure declarations are read only when that is true. 1091 * Applications using the library should not include jpegint.h, but may wish 1092 * to include jerror.h. 1093 */ 1094 1095 #ifdef JPEG_INTERNALS 1096 #include "jpegint.h" /* fetch private declarations */ 1097 #include "jerror.h" /* fetch error codes too */ 1098 #endif 1099 1100 #endif /* JPEGLIB_H */ 1101
