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