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 data units 50 * per MCU. 51 * If you happen to run across such a file, you can up D_MAX_DATA_UNITS_IN_MCU 52 * to handle it. We even let you do this from the jconfig.h file. However, 53 * we strongly discourage changing C_MAX_DATA_UNITS_IN_MCU; just because Adobe 54 * sometimes emits noncompliant files doesn't mean you should too. 55 */ 56 #define C_MAX_DATA_UNITS_IN_MCU 10 /* compressor's limit on data units/MCU */ 57 #ifndef D_MAX_DATA_UNITS_IN_MCU 58 #define D_MAX_DATA_UNITS_IN_MCU 10 /* decompressor's limit on data units/MCU */ 59 #endif 60 61 62 /* Data structures for images (arrays of samples and of DCT coefficients). 63 * On 80x86 machines, the image arrays are too big for near pointers, 64 * but the pointer arrays can fit in near memory. 65 */ 66 67 typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */ 68 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ 69 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ 70 71 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ 72 typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */ 73 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ 74 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ 75 76 typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */ 77 78 typedef JDIFF FAR *JDIFFROW; /* pointer to one row of difference values */ 79 typedef JDIFFROW *JDIFFARRAY; /* ptr to some rows (a 2-D diff array) */ 80 typedef JDIFFARRAY *JDIFFIMAGE; /* a 3-D diff array: top index is color */ 81 82 83 /* Types for JPEG compression parameters and working tables. */ 84 85 86 /* DCT coefficient quantization tables. */ 87 88 typedef struct { 89 /* This array gives the coefficient quantizers in natural array order 90 * (not the zigzag order in which they are stored in a JPEG DQT marker). 91 * CAUTION: IJG versions prior to v6a kept this array in zigzag order. 92 */ 93 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */ 94 /* This field is used only during compression. It's initialized FALSE when 95 * the table is created, and set TRUE when it's been output to the file. 96 * You could suppress output of a table by setting this to TRUE. 97 * (See jpeg_suppress_tables for an example.) 98 */ 99 boolean sent_table; /* TRUE when table has been output */ 100 } JQUANT_TBL; 101 102 103 /* Huffman coding tables. */ 104 105 typedef struct { 106 /* These two fields directly represent the contents of a JPEG DHT marker */ 107 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ 108 /* length k bits; bits[0] is unused */ 109 UINT8 huffval[256]; /* The symbols, in order of incr code length */ 110 /* This field is used only during compression. It's initialized FALSE when 111 * the table is created, and set TRUE when it's been output to the file. 112 * You could suppress output of a table by setting this to TRUE. 113 * (See jpeg_suppress_tables for an example.) 114 */ 115 boolean sent_table; /* TRUE when table has been output */ 116 } JHUFF_TBL; 117 118 119 /* Basic info about one component (color channel). */ 120 121 typedef struct { 122 /* These values are fixed over the whole image. */ 123 /* For compression, they must be supplied by parameter setup; */ 124 /* for decompression, they are read from the SOF marker. */ 125 int component_id; /* identifier for this component (0..255) */ 126 int component_index; /* its index in SOF or cinfo->comp_info[] */ 127 int h_samp_factor; /* horizontal sampling factor (1..4) */ 128 int v_samp_factor; /* vertical sampling factor (1..4) */ 129 int quant_tbl_no; /* quantization table selector (0..3) */ 130 /* These values may vary between scans. */ 131 /* For compression, they must be supplied by parameter setup; */ 132 /* for decompression, they are read from the SOS marker. */ 133 /* The decompressor output side may not use these variables. */ 134 int dc_tbl_no; /* DC entropy table selector (0..3) */ 135 int ac_tbl_no; /* AC entropy table selector (0..3) */ 136 137 /* Remaining fields should be treated as private by applications. */ 138 139 /* These values are computed during compression or decompression startup: */ 140 /* Component's size in data units. 141 * Any dummy data units added to complete an MCU are not counted; therefore 142 * these values do not depend on whether a scan is interleaved or not. 143 */ 144 JDIMENSION width_in_data_units; 145 JDIMENSION height_in_data_units; 146 /* Size of a data unit in/output by the codec (in samples). Always 147 * data_unit for compression. For decompression this is the size of the 148 * output from one data_unit, reflecting any processing performed by the 149 * codec. For example, in the DCT-based codec, scaling may be applied 150 * during the IDCT step. Values of 1,2,4,8 are likely to be supported. 151 * Note that different components may have different codec_data_unit sizes. 152 */ 153 int codec_data_unit; 154 /* The downsampled dimensions are the component's actual, unpadded number 155 * of samples at the main buffer (preprocessing/compression interface), thus 156 * downsampled_width = ceil(image_width * Hi/Hmax) 157 * and similarly for height. For decompression, codec-based processing is 158 * included (ie, IDCT scaling), so 159 * downsampled_width = ceil(image_width * Hi/Hmax * codec_data_unit/data_unit) 160 */ 161 JDIMENSION downsampled_width; /* actual width in samples */ 162 JDIMENSION downsampled_height; /* actual height in samples */ 163 /* This flag is used only for decompression. In cases where some of the 164 * components will be ignored (eg grayscale output from YCbCr image), 165 * we can skip most computations for the unused components. 166 */ 167 boolean component_needed; /* do we need the value of this component? */ 168 169 /* These values are computed before starting a scan of the component. */ 170 /* The decompressor output side may not use these variables. */ 171 int MCU_width; /* number of data units per MCU, horizontally */ 172 int MCU_height; /* number of data units per MCU, vertically */ 173 int MCU_data_units; /* MCU_width * MCU_height */ 174 int MCU_sample_width; /* MCU width in samples, MCU_width*codec_data_unit */ 175 int last_col_width; /* # of non-dummy data_units across in last MCU */ 176 int last_row_height; /* # of non-dummy data_units down in last MCU */ 177 178 /* Saved quantization table for component; NULL if none yet saved. 179 * See jdinput.c comments about the need for this information. 180 * This field is currently used only for decompression. 181 */ 182 JQUANT_TBL * quant_table; 183 184 /* Private per-component storage for DCT or IDCT subsystem. */ 185 void * dct_table; 186 } jpeg_component_info; 187 188 189 /* The script for encoding a multiple-scan file is an array of these: */ 190 191 typedef struct { 192 int comps_in_scan; /* number of components encoded in this scan */ 193 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */ 194 int Ss, Se; /* progressive JPEG spectral selection parms 195 lossless JPEG predictor select parm (Ss) */ 196 int Ah, Al; /* progressive JPEG successive approx. parms 197 lossless JPEG point transform parm (Al) */ 198 } jpeg_scan_info; 199 200 /* The decompressor can save APPn and COM markers in a list of these: */ 201 202 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr; 203 204 struct jpeg_marker_struct { 205 jpeg_saved_marker_ptr next; /* next in list, or NULL */ 206 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */ 207 unsigned int original_length; /* # bytes of data in the file */ 208 unsigned int data_length; /* # bytes of data saved at data[] */ 209 JOCTET FAR * data; /* the data contained in the marker */ 210 /* the marker length word is not counted in data_length or original_length */ 211 }; 212 213 /* Known codec processes. */ 214 215 typedef enum { 216 JPROC_SEQUENTIAL, /* baseline/extended sequential DCT */ 217 JPROC_PROGRESSIVE, /* progressive DCT */ 218 JPROC_LOSSLESS /* lossless (sequential) */ 219 } J_CODEC_PROCESS; 220 221 /* Known color spaces. */ 222 223 typedef enum { 224 JCS_UNKNOWN, /* error/unspecified */ 225 JCS_GRAYSCALE, /* monochrome */ 226 JCS_RGB, /* red/green/blue */ 227 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ 228 JCS_CMYK, /* C/M/Y/K */ 229 JCS_YCCK /* Y/Cb/Cr/K */ 230 } J_COLOR_SPACE; 231 232 /* DCT/IDCT algorithm options. */ 233 234 typedef enum { 235 JDCT_ISLOW, /* slow but accurate integer algorithm */ 236 JDCT_IFAST, /* faster, less accurate integer method */ 237 JDCT_FLOAT /* floating-point: accurate, fast on fast HW */ 238 } J_DCT_METHOD; 239 240 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */ 241 #define JDCT_DEFAULT JDCT_ISLOW 242 #endif 243 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */ 244 #define JDCT_FASTEST JDCT_IFAST 245 #endif 246 247 /* Dithering options for decompression. */ 248 249 typedef enum { 250 JDITHER_NONE, /* no dithering */ 251 JDITHER_ORDERED, /* simple ordered dither */ 252 JDITHER_FS /* Floyd-Steinberg error diffusion dither */ 253 } J_DITHER_MODE; 254 255 256 /* Common fields between JPEG compression and decompression master structs. */ 257 258 #define jpeg_common_fields \ 259 struct jpeg_error_mgr * err; /* Error handler module */\ 260 struct jpeg_memory_mgr * mem; /* Memory manager module */\ 261 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\ 262 void * client_data; /* Available for use by application */\ 263 boolean is_decompressor; /* So common code can tell which is which */\ 264 int global_state /* For checking call sequence validity */ 265 266 /* Routines that are to be used by both halves of the library are declared 267 * to receive a pointer to this structure. There are no actual instances of 268 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct. 269 */ 270 struct jpeg_common_struct { 271 jpeg_common_fields; /* Fields common to both master struct types */ 272 /* Additional fields follow in an actual jpeg_compress_struct or 273 * jpeg_decompress_struct. All three structs must agree on these 274 * initial fields! (This would be a lot cleaner in C++.) 275 */ 276 }; 277 278 typedef struct jpeg_common_struct * j_common_ptr; 279 typedef struct jpeg_compress_struct * j_compress_ptr; 280 typedef struct jpeg_decompress_struct * j_decompress_ptr; 281 282 283 /* Master record for a compression instance */ 284 285 struct jpeg_compress_struct { 286 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */ 287 288 /* Destination for compressed data */ 289 struct jpeg_destination_mgr * dest; 290 291 /* Description of source image --- these fields must be filled in by 292 * outer application before starting compression. in_color_space must 293 * be correct before you can even call jpeg_set_defaults(). 294 */ 295 296 JDIMENSION image_width; /* input image width */ 297 JDIMENSION image_height; /* input image height */ 298 int input_components; /* # of color components in input image */ 299 J_COLOR_SPACE in_color_space; /* colorspace of input image */ 300 301 double input_gamma; /* image gamma of input image */ 302 303 /* Compression parameters --- these fields must be set before calling 304 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to 305 * initialize everything to reasonable defaults, then changing anything 306 * the application specifically wants to change. That way you won't get 307 * burnt when new parameters are added. Also note that there are several 308 * helper routines to simplify changing parameters. 309 */ 310 311 boolean lossless; /* TRUE=lossless encoding, FALSE=lossy */ 312 313 int data_precision; /* bits of precision in image data */ 314 315 int num_components; /* # of color components in JPEG image */ 316 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 317 318 jpeg_component_info * comp_info; 319 /* comp_info[i] describes component that appears i'th in SOF */ 320 321 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 322 /* ptrs to coefficient quantization tables, or NULL if not defined */ 323 324 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 325 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 326 /* ptrs to Huffman coding tables, or NULL if not defined */ 327 328 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 329 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 330 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 331 332 int num_scans; /* # of entries in scan_info array */ 333 const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */ 334 /* The default value of scan_info is NULL, which causes a single-scan 335 * sequential JPEG file to be emitted. To create a multi-scan file, 336 * set num_scans and scan_info to point to an array of scan definitions. 337 */ 338 339 boolean raw_data_in; /* TRUE=caller supplies downsampled data */ 340 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 341 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ 342 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 343 int smoothing_factor; /* 1..100, or 0 for no input smoothing */ 344 J_DCT_METHOD dct_method; /* DCT algorithm selector */ 345 346 /* The restart interval can be specified in absolute MCUs by setting 347 * restart_interval, or in MCU rows by setting restart_in_rows 348 * (in which case the correct restart_interval will be figured 349 * for each scan). 350 */ 351 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */ 352 int restart_in_rows; /* if > 0, MCU rows per restart interval */ 353 354 /* Parameters controlling emission of special markers. */ 355 356 boolean write_JFIF_header; /* should a JFIF marker be written? */ 357 UINT8 JFIF_major_version; /* What to write for the JFIF version number */ 358 UINT8 JFIF_minor_version; 359 /* These three values are not used by the JPEG code, merely copied */ 360 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ 361 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ 362 /* ratio is defined by X_density/Y_density even when density_unit=0. */ 363 UINT8 density_unit; /* JFIF code for pixel size units */ 364 UINT16 X_density; /* Horizontal pixel density */ 365 UINT16 Y_density; /* Vertical pixel density */ 366 boolean write_Adobe_marker; /* should an Adobe marker be written? */ 367 368 /* State variable: index of next scanline to be written to 369 * jpeg_write_scanlines(). Application may use this to control its 370 * processing loop, e.g., "while (next_scanline < image_height)". 371 */ 372 373 JDIMENSION next_scanline; /* 0 .. image_height-1 */ 374 375 /* Remaining fields are known throughout compressor, but generally 376 * should not be touched by a surrounding application. 377 */ 378 379 /* 380 * These fields are computed during compression startup 381 */ 382 int data_unit; /* size of data unit in samples */ 383 J_CODEC_PROCESS process; /* encoding process of JPEG image */ 384 385 int max_h_samp_factor; /* largest h_samp_factor */ 386 int max_v_samp_factor; /* largest v_samp_factor */ 387 388 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to codec */ 389 /* The codec receives data in units of MCU rows as defined for fully 390 * interleaved scans (whether the JPEG file is interleaved or not). 391 * There are v_samp_factor * data_unit sample rows of each component in an 392 * "iMCU" (interleaved MCU) row. 393 */ 394 395 /* 396 * These fields are valid during any one scan. 397 * They describe the components and MCUs actually appearing in the scan. 398 */ 399 int comps_in_scan; /* # of JPEG components in this scan */ 400 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 401 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 402 403 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 404 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 405 406 int data_units_in_MCU; /* # of data units per MCU */ 407 int MCU_membership[C_MAX_DATA_UNITS_IN_MCU]; 408 /* MCU_membership[i] is index in cur_comp_info of component owning */ 409 /* i'th block in an MCU */ 410 411 int Ss, Se, Ah, Al; /* progressive/lossless JPEG parameters for scan */ 412 413 /* 414 * Links to compression subobjects (methods and private variables of modules) 415 */ 416 struct jpeg_comp_master * master; 417 struct jpeg_c_main_controller * main; 418 struct jpeg_c_prep_controller * prep; 419 struct jpeg_c_codec * codec; 420 struct jpeg_marker_writer * marker; 421 struct jpeg_color_converter * cconvert; 422 struct jpeg_downsampler * downsample; 423 jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */ 424 int script_space_size; 425 }; 426 427 428 /* Master record for a decompression instance */ 429 430 struct jpeg_decompress_struct { 431 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */ 432 433 /* Source of compressed data */ 434 struct jpeg_source_mgr * src; 435 436 /* Basic description of image --- filled in by jpeg_read_header(). */ 437 /* Application may inspect these values to decide how to process image. */ 438 439 JDIMENSION image_width; /* nominal image width (from SOF marker) */ 440 JDIMENSION image_height; /* nominal image height */ 441 int num_components; /* # of color components in JPEG image */ 442 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 443 444 /* Decompression processing parameters --- these fields must be set before 445 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes 446 * them to default values. 447 */ 448 449 J_COLOR_SPACE out_color_space; /* colorspace for output */ 450 451 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 452 453 double output_gamma; /* image gamma wanted in output */ 454 455 boolean buffered_image; /* TRUE=multiple output passes */ 456 boolean raw_data_out; /* TRUE=downsampled data wanted */ 457 458 J_DCT_METHOD dct_method; /* IDCT algorithm selector */ 459 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */ 460 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */ 461 462 boolean quantize_colors; /* TRUE=colormapped output wanted */ 463 /* the following are ignored if not quantize_colors: */ 464 J_DITHER_MODE dither_mode; /* type of color dithering to use */ 465 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */ 466 int desired_number_of_colors; /* max # colors to use in created colormap */ 467 /* these are significant only in buffered-image mode: */ 468 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */ 469 boolean enable_external_quant;/* enable future use of external colormap */ 470 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */ 471 472 /* Description of actual output image that will be returned to application. 473 * These fields are computed by jpeg_start_decompress(). 474 * You can also use jpeg_calc_output_dimensions() to determine these values 475 * in advance of calling jpeg_start_decompress(). 476 */ 477 478 JDIMENSION output_width; /* scaled image width */ 479 JDIMENSION output_height; /* scaled image height */ 480 int out_color_components; /* # of color components in out_color_space */ 481 int output_components; /* # of color components returned */ 482 /* output_components is 1 (a colormap index) when quantizing colors; 483 * otherwise it equals out_color_components. 484 */ 485 int rec_outbuf_height; /* min recommended height of scanline buffer */ 486 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows 487 * high, space and time will be wasted due to unnecessary data copying. 488 * Usually rec_outbuf_height will be 1 or 2, at most 4. 489 */ 490 491 /* When quantizing colors, the output colormap is described by these fields. 492 * The application can supply a colormap by setting colormap non-NULL before 493 * calling jpeg_start_decompress; otherwise a colormap is created during 494 * jpeg_start_decompress or jpeg_start_output. 495 * The map has out_color_components rows and actual_number_of_colors columns. 496 */ 497 int actual_number_of_colors; /* number of entries in use */ 498 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */ 499 500 /* State variables: these variables indicate the progress of decompression. 501 * The application may examine these but must not modify them. 502 */ 503 504 /* Row index of next scanline to be read from jpeg_read_scanlines(). 505 * Application may use this to control its processing loop, e.g., 506 * "while (output_scanline < output_height)". 507 */ 508 JDIMENSION output_scanline; /* 0 .. output_height-1 */ 509 510 /* Current input scan number and number of iMCU rows completed in scan. 511 * These indicate the progress of the decompressor input side. 512 */ 513 int input_scan_number; /* Number of SOS markers seen so far */ 514 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */ 515 516 /* The "output scan number" is the notional scan being displayed by the 517 * output side. The decompressor will not allow output scan/row number 518 * to get ahead of input scan/row, but it can fall arbitrarily far behind. 519 */ 520 int output_scan_number; /* Nominal scan number being displayed */ 521 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */ 522 523 /* Current progression status. coef_bits[c][i] indicates the precision 524 * with which component c's DCT coefficient i (in zigzag order) is known. 525 * It is -1 when no data has yet been received, otherwise it is the point 526 * transform (shift) value for the most recent scan of the coefficient 527 * (thus, 0 at completion of the progression). 528 * This pointer is NULL when reading a non-progressive file. 529 */ 530 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */ 531 532 /* Internal JPEG parameters --- the application usually need not look at 533 * these fields. Note that the decompressor output side may not use 534 * any parameters that can change between scans. 535 */ 536 537 /* Quantization and Huffman tables are carried forward across input 538 * datastreams when processing abbreviated JPEG datastreams. 539 */ 540 541 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 542 /* ptrs to coefficient quantization tables, or NULL if not defined */ 543 544 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 545 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 546 /* ptrs to Huffman coding tables, or NULL if not defined */ 547 548 /* These parameters are never carried across datastreams, since they 549 * are given in SOF/SOS markers or defined to be reset by SOI. 550 */ 551 552 int data_precision; /* bits of precision in image data */ 553 554 jpeg_component_info * comp_info; 555 /* comp_info[i] describes component that appears i'th in SOF */ 556 557 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 558 559 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 560 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 561 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 562 563 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */ 564 565 /* These fields record data obtained from optional markers recognized by 566 * the JPEG library. 567 */ 568 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */ 569 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */ 570 UINT8 JFIF_major_version; /* JFIF version number */ 571 UINT8 JFIF_minor_version; 572 UINT8 density_unit; /* JFIF code for pixel size units */ 573 UINT16 X_density; /* Horizontal pixel density */ 574 UINT16 Y_density; /* Vertical pixel density */ 575 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */ 576 UINT8 Adobe_transform; /* Color transform code from Adobe marker */ 577 578 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 579 580 /* Aside from the specific data retained from APPn markers known to the 581 * library, the uninterpreted contents of any or all APPn and COM markers 582 * can be saved in a list for examination by the application. 583 */ 584 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */ 585 586 /* Remaining fields are known throughout decompressor, but generally 587 * should not be touched by a surrounding application. 588 */ 589 590 /* 591 * These fields are computed during decompression startup 592 */ 593 int data_unit; /* size of data unit in samples */ 594 J_CODEC_PROCESS process; /* decoding process of JPEG image */ 595 596 int max_h_samp_factor; /* largest h_samp_factor */ 597 int max_v_samp_factor; /* largest v_samp_factor */ 598 599 int min_codec_data_unit; /* smallest codec_data_unit of any component */ 600 601 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ 602 /* The codec's input and output progress is measured in units of "iMCU" 603 * (interleaved MCU) rows. These are the same as MCU rows in fully 604 * interleaved JPEG scans, but are used whether the scan is interleaved 605 * or not. We define an iMCU row as v_samp_factor data_unit rows of each 606 * component. Therefore, the codec output contains 607 * v_samp_factor*codec_data_unit sample rows of a component per iMCU row. 608 */ 609 610 JSAMPLE * sample_range_limit; /* table for fast range-limiting */ 611 612 /* 613 * These fields are valid during any one scan. 614 * They describe the components and MCUs actually appearing in the scan. 615 * Note that the decompressor output side must not use these fields. 616 */ 617 int comps_in_scan; /* # of JPEG components in this scan */ 618 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 619 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 620 621 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 622 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 623 624 int data_units_in_MCU; /* # of data _units per MCU */ 625 int MCU_membership[D_MAX_DATA_UNITS_IN_MCU]; 626 /* MCU_membership[i] is index in cur_comp_info of component owning */ 627 /* i'th data unit in an MCU */ 628 629 int Ss, Se, Ah, Al; /* progressive/lossless JPEG parms for scan */ 630 631 /* This field is shared between entropy decoder and marker parser. 632 * It is either zero or the code of a JPEG marker that has been 633 * read from the data source, but has not yet been processed. 634 */ 635 int unread_marker; 636 637 /* 638 * Links to decompression subobjects (methods, private variables of modules) 639 */ 640 struct jpeg_decomp_master * master; 641 struct jpeg_d_main_controller * main; 642 struct jpeg_d_codec * codec; 643 struct jpeg_d_post_controller * post; 644 struct jpeg_input_controller * inputctl; 645 struct jpeg_marker_reader * marker; 646 struct jpeg_upsampler * upsample; 647 struct jpeg_color_deconverter * cconvert; 648 struct jpeg_color_quantizer * cquantize; 649 }; 650 651 652 /* "Object" declarations for JPEG modules that may be supplied or called 653 * directly by the surrounding application. 654 * As with all objects in the JPEG library, these structs only define the 655 * publicly visible methods and state variables of a module. Additional 656 * private fields may exist after the public ones. 657 */ 658 659 660 /* Error handler object */ 661 662 struct jpeg_error_mgr { 663 /* Error exit handler: does not return to caller */ 664 JMETHOD(void, error_exit, (j_common_ptr cinfo)); 665 /* Conditionally emit a trace or warning message */ 666 JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level)); 667 /* Routine that actually outputs a trace or error message */ 668 JMETHOD(void, output_message, (j_common_ptr cinfo)); 669 /* Format a message string for the most recent JPEG error or message */ 670 JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer)); 671 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */ 672 /* Reset error state variables at start of a new image */ 673 JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo)); 674 675 /* The message ID code and any parameters are saved here. 676 * A message can have one string parameter or up to 8 int parameters. 677 */ 678 int msg_code; 679 #define JMSG_STR_PARM_MAX 80 680 union { 681 int i[8]; 682 char s[JMSG_STR_PARM_MAX]; 683 } msg_parm; 684 685 /* Standard state variables for error facility */ 686 687 int trace_level; /* max msg_level that will be displayed */ 688 689 /* For recoverable corrupt-data errors, we emit a warning message, 690 * but keep going unless emit_message chooses to abort. emit_message 691 * should count warnings in num_warnings. The surrounding application 692 * can check for bad data by seeing if num_warnings is nonzero at the 693 * end of processing. 694 */ 695 long num_warnings; /* number of corrupt-data warnings */ 696 697 /* These fields point to the table(s) of error message strings. 698 * An application can change the table pointer to switch to a different 699 * message list (typically, to change the language in which errors are 700 * reported). Some applications may wish to add additional error codes 701 * that will be handled by the JPEG library error mechanism; the second 702 * table pointer is used for this purpose. 703 * 704 * First table includes all errors generated by JPEG library itself. 705 * Error code 0 is reserved for a "no such error string" message. 706 */ 707 const char * const * jpeg_message_table; /* Library errors */ 708 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */ 709 /* Second table can be added by application (see cjpeg/djpeg for example). 710 * It contains strings numbered first_addon_message..last_addon_message. 711 */ 712 const char * const * addon_message_table; /* Non-library errors */ 713 int first_addon_message; /* code for first string in addon table */ 714 int last_addon_message; /* code for last string in addon table */ 715 }; 716 717 718 /* Progress monitor object */ 719 720 struct jpeg_progress_mgr { 721 JMETHOD(void, progress_monitor, (j_common_ptr cinfo)); 722 723 long pass_counter; /* work units completed in this pass */ 724 long pass_limit; /* total number of work units in this pass */ 725 int completed_passes; /* passes completed so far */ 726 int total_passes; /* total number of passes expected */ 727 }; 728 729 730 /* Data destination object for compression */ 731 732 struct jpeg_destination_mgr { 733 JOCTET * next_output_byte; /* => next byte to write in buffer */ 734 size_t free_in_buffer; /* # of byte spaces remaining in buffer */ 735 736 JMETHOD(void, init_destination, (j_compress_ptr cinfo)); 737 JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo)); 738 JMETHOD(void, term_destination, (j_compress_ptr cinfo)); 739 }; 740 741 742 /* Data source object for decompression */ 743 744 struct jpeg_source_mgr { 745 const JOCTET * next_input_byte; /* => next byte to read from buffer */ 746 size_t bytes_in_buffer; /* # of bytes remaining in buffer */ 747 748 JMETHOD(void, init_source, (j_decompress_ptr cinfo)); 749 JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo)); 750 JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes)); 751 JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired)); 752 JMETHOD(void, term_source, (j_decompress_ptr cinfo)); 753 }; 754 755 756 /* Memory manager object. 757 * Allocates "small" objects (a few K total), "large" objects (tens of K), 758 * and "really big" objects (virtual arrays with backing store if needed). 759 * The memory manager does not allow individual objects to be freed; rather, 760 * each created object is assigned to a pool, and whole pools can be freed 761 * at once. This is faster and more convenient than remembering exactly what 762 * to free, especially where malloc()/free() are not too speedy. 763 * NB: alloc routines never return NULL. They exit to error_exit if not 764 * successful. 765 */ 766 767 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */ 768 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */ 769 #define JPOOL_NUMPOOLS 2 770 771 typedef struct jvirt_sarray_control * jvirt_sarray_ptr; 772 typedef struct jvirt_barray_control * jvirt_barray_ptr; 773 774 775 #ifdef C_LOSSLESS_SUPPORTED 776 #define NEED_DARRAY 777 #else 778 #ifdef D_LOSSLESS_SUPPORTED 779 #define NEED_DARRAY 780 #endif 781 #endif 782 783 struct jpeg_memory_mgr { 784 /* Method pointers */ 785 JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id, 786 size_t sizeofobject)); 787 JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id, 788 size_t sizeofobject)); 789 JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id, 790 JDIMENSION samplesperrow, 791 JDIMENSION numrows)); 792 JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id, 793 JDIMENSION blocksperrow, 794 JDIMENSION numrows)); 795 #ifdef NEED_DARRAY 796 JMETHOD(JDIFFARRAY, alloc_darray, (j_common_ptr cinfo, int pool_id, 797 JDIMENSION diffsperrow, 798 JDIMENSION numrows)); 799 #endif 800 JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo, 801 int pool_id, 802 boolean pre_zero, 803 JDIMENSION samplesperrow, 804 JDIMENSION numrows, 805 JDIMENSION maxaccess)); 806 JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo, 807 int pool_id, 808 boolean pre_zero, 809 JDIMENSION blocksperrow, 810 JDIMENSION numrows, 811 JDIMENSION maxaccess)); 812 JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo)); 813 JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo, 814 jvirt_sarray_ptr ptr, 815 JDIMENSION start_row, 816 JDIMENSION num_rows, 817 boolean writable)); 818 JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo, 819 jvirt_barray_ptr ptr, 820 JDIMENSION start_row, 821 JDIMENSION num_rows, 822 boolean writable)); 823 JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id)); 824 JMETHOD(void, self_destruct, (j_common_ptr cinfo)); 825 826 /* Limit on memory allocation for this JPEG object. (Note that this is 827 * merely advisory, not a guaranteed maximum; it only affects the space 828 * used for virtual-array buffers.) May be changed by outer application 829 * after creating the JPEG object. 830 */ 831 long max_memory_to_use; 832 833 /* Maximum allocation request accepted by alloc_large. */ 834 long max_alloc_chunk; 835 }; 836 837 838 /* Routine signature for application-supplied marker processing methods. 839 * Need not pass marker code since it is stored in cinfo->unread_marker. 840 */ 841 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo)); 842 843 844 /* Declarations for routines called by application. 845 * The JPP macro hides prototype parameters from compilers that can't cope. 846 * Note JPP requires double parentheses. 847 */ 848 849 #ifdef HAVE_PROTOTYPES 850 #define JPP(arglist) arglist 851 #else 852 #define JPP(arglist) () 853 #endif 854 855 856 /* Short forms of external names for systems with brain-damaged linkers. 857 * We shorten external names to be unique in the first six letters, which 858 * is good enough for all known systems. 859 * (If your compiler itself needs names to be unique in less than 15 860 * characters, you are out of luck. Get a better compiler.) 861 */ 862 863 #ifdef NEED_SHORT_EXTERNAL_NAMES 864 #define jpeg_std_error jStdError 865 #define jpeg_CreateCompress jCreaCompress 866 #define jpeg_CreateDecompress jCreaDecompress 867 #define jpeg_destroy_compress jDestCompress 868 #define jpeg_destroy_decompress jDestDecompress 869 #define jpeg_stdio_dest jStdDest 870 #define jpeg_stdio_src jStdSrc 871 #define jpeg_set_defaults jSetDefaults 872 #define jpeg_set_colorspace jSetColorspace 873 #define jpeg_default_colorspace jDefColorspace 874 #define jpeg_set_quality jSetQuality 875 #define jpeg_set_linear_quality jSetLQuality 876 #define jpeg_add_quant_table jAddQuantTable 877 #define jpeg_quality_scaling jQualityScaling 878 #define jpeg_simple_lossless jSimLossless 879 #define jpeg_simple_progression jSimProgress 880 #define jpeg_suppress_tables jSuppressTables 881 #define jpeg_alloc_quant_table jAlcQTable 882 #define jpeg_alloc_huff_table jAlcHTable 883 #define jpeg_start_compress jStrtCompress 884 #define jpeg_write_scanlines jWrtScanlines 885 #define jpeg_finish_compress jFinCompress 886 #define jpeg_write_raw_data jWrtRawData 887 #define jpeg_write_marker jWrtMarker 888 #define jpeg_write_m_header jWrtMHeader 889 #define jpeg_write_m_byte jWrtMByte 890 #define jpeg_write_tables jWrtTables 891 #define jpeg_read_header jReadHeader 892 #define jpeg_start_decompress jStrtDecompress 893 #define jpeg_read_scanlines jReadScanlines 894 #define jpeg_finish_decompress jFinDecompress 895 #define jpeg_read_raw_data jReadRawData 896 #define jpeg_has_multiple_scans jHasMultScn 897 #define jpeg_start_output jStrtOutput 898 #define jpeg_finish_output jFinOutput 899 #define jpeg_input_complete jInComplete 900 #define jpeg_new_colormap jNewCMap 901 #define jpeg_consume_input jConsumeInput 902 #define jpeg_calc_output_dimensions jCalcDimensions 903 #define jpeg_save_markers jSaveMarkers 904 #define jpeg_set_marker_processor jSetMarker 905 #define jpeg_read_coefficients jReadCoefs 906 #define jpeg_write_coefficients jWrtCoefs 907 #define jpeg_copy_critical_parameters jCopyCrit 908 #define jpeg_abort_compress jAbrtCompress 909 #define jpeg_abort_decompress jAbrtDecompress 910 #define jpeg_abort jAbort 911 #define jpeg_destroy jDestroy 912 #define jpeg_resync_to_restart jResyncRestart 913 #endif /* NEED_SHORT_EXTERNAL_NAMES */ 914 915 916 /* Default error-management setup */ 917 EXTERN(struct jpeg_error_mgr *) jpeg_std_error 918 JPP((struct jpeg_error_mgr * err)); 919 920 /* Initialization of JPEG compression objects. 921 * jpeg_create_compress() and jpeg_create_decompress() are the exported 922 * names that applications should call. These expand to calls on 923 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information 924 * passed for version mismatch checking. 925 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx. 926 */ 927 #define jpeg_create_compress(cinfo) \ 928 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \ 929 (size_t) sizeof(struct jpeg_compress_struct)) 930 #define jpeg_create_decompress(cinfo) \ 931 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \ 932 (size_t) sizeof(struct jpeg_decompress_struct)) 933 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo, 934 int version, size_t structsize)); 935 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo, 936 int version, size_t structsize)); 937 /* Destruction of JPEG compression objects */ 938 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo)); 939 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo)); 940 941 /* Standard data source and destination managers: stdio streams. */ 942 /* Caller is responsible for opening the file before and closing after. */ 943 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile)); 944 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile)); 945 946 /* Default parameter setup for compression */ 947 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo)); 948 /* Compression parameter setup aids */ 949 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo, 950 J_COLOR_SPACE colorspace)); 951 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo)); 952 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality, 953 boolean force_baseline)); 954 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo, 955 int scale_factor, 956 boolean force_baseline)); 957 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl, 958 const unsigned int *basic_table, 959 int scale_factor, 960 boolean force_baseline)); 961 EXTERN(int) jpeg_quality_scaling JPP((int quality)); 962 EXTERN(void) jpeg_simple_lossless JPP((j_compress_ptr cinfo, 963 int predictor, int point_transform)); 964 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo)); 965 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo, 966 boolean suppress)); 967 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo)); 968 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo)); 969 970 /* Main entry points for compression */ 971 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo, 972 boolean write_all_tables)); 973 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo, 974 JSAMPARRAY scanlines, 975 JDIMENSION num_lines)); 976 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo)); 977 978 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */ 979 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo, 980 JSAMPIMAGE data, 981 JDIMENSION num_lines)); 982 983 /* Write a special marker. See libjpeg.doc concerning safe usage. */ 984 EXTERN(void) jpeg_write_marker 985 JPP((j_compress_ptr cinfo, int marker, 986 const JOCTET * dataptr, unsigned int datalen)); 987 /* Same, but piecemeal. */ 988 EXTERN(void) jpeg_write_m_header 989 JPP((j_compress_ptr cinfo, int marker, unsigned int datalen)); 990 EXTERN(void) jpeg_write_m_byte 991 JPP((j_compress_ptr cinfo, int val)); 992 993 /* Alternate compression function: just write an abbreviated table file */ 994 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo)); 995 996 /* Decompression startup: read start of JPEG datastream to see what's there */ 997 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo, 998 boolean require_image)); 999 /* Return value is one of: */ 1000 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */ 1001 #define JPEG_HEADER_OK 1 /* Found valid image datastream */ 1002 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */ 1003 /* If you pass require_image = TRUE (normal case), you need not check for 1004 * a TABLES_ONLY return code; an abbreviated file will cause an error exit. 1005 * JPEG_SUSPENDED is only possible if you use a data source module that can 1006 * give a suspension return (the stdio source module doesn't). 1007 */ 1008 1009 /* Main entry points for decompression */ 1010 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo)); 1011 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo, 1012 JSAMPARRAY scanlines, 1013 JDIMENSION max_lines)); 1014 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo)); 1015 1016 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */ 1017 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo, 1018 JSAMPIMAGE data, 1019 JDIMENSION max_lines)); 1020 1021 /* Additional entry points for buffered-image mode. */ 1022 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo)); 1023 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo, 1024 int scan_number)); 1025 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo)); 1026 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo)); 1027 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo)); 1028 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo)); 1029 /* Return value is one of: */ 1030 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */ 1031 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */ 1032 #define JPEG_REACHED_EOI 2 /* Reached end of image */ 1033 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */ 1034 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */ 1035 1036 /* Precalculate output dimensions for current decompression parameters. */ 1037 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo)); 1038 1039 /* Control saving of COM and APPn markers into marker_list. */ 1040 EXTERN(void) jpeg_save_markers 1041 JPP((j_decompress_ptr cinfo, int marker_code, 1042 unsigned int length_limit)); 1043 1044 /* Install a special processing method for COM or APPn markers. */ 1045 EXTERN(void) jpeg_set_marker_processor 1046 JPP((j_decompress_ptr cinfo, int marker_code, 1047 jpeg_marker_parser_method routine)); 1048 1049 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */ 1050 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo)); 1051 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo, 1052 jvirt_barray_ptr * coef_arrays)); 1053 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo, 1054 j_compress_ptr dstinfo)); 1055 1056 /* If you choose to abort compression or decompression before completing 1057 * jpeg_finish_(de)compress, then you need to clean up to release memory, 1058 * temporary files, etc. You can just call jpeg_destroy_(de)compress 1059 * if you're done with the JPEG object, but if you want to clean it up and 1060 * reuse it, call this: 1061 */ 1062 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo)); 1063 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo)); 1064 1065 /* Generic versions of jpeg_abort and jpeg_destroy that work on either 1066 * flavor of JPEG object. These may be more convenient in some places. 1067 */ 1068 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo)); 1069 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo)); 1070 1071 /* Default restart-marker-resync procedure for use by data source modules */ 1072 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo, 1073 int desired)); 1074 1075 1076 /* These marker codes are exported since applications and data source modules 1077 * are likely to want to use them. 1078 */ 1079 1080 #define JPEG_RST0 0xD0 /* RST0 marker code */ 1081 #define JPEG_EOI 0xD9 /* EOI marker code */ 1082 #define JPEG_APP0 0xE0 /* APP0 marker code */ 1083 #define JPEG_COM 0xFE /* COM marker code */ 1084 1085 1086 /* If we have a brain-damaged compiler that emits warnings (or worse, errors) 1087 * for structure definitions that are never filled in, keep it quiet by 1088 * supplying dummy definitions for the various substructures. 1089 */ 1090 1091 #ifdef INCOMPLETE_TYPES_BROKEN 1092 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */ 1093 struct jvirt_sarray_control { long dummy; }; 1094 struct jvirt_barray_control { long dummy; }; 1095 struct jpeg_comp_master { long dummy; }; 1096 struct jpeg_c_main_controller { long dummy; }; 1097 struct jpeg_c_prep_controller { long dummy; }; 1098 struct jpeg_c_coef_controller { long dummy; }; 1099 struct jpeg_marker_writer { long dummy; }; 1100 struct jpeg_color_converter { long dummy; }; 1101 struct jpeg_downsampler { long dummy; }; 1102 struct jpeg_forward_dct { long dummy; }; 1103 struct jpeg_entropy_encoder { long dummy; }; 1104 struct jpeg_decomp_master { long dummy; }; 1105 struct jpeg_d_main_controller { long dummy; }; 1106 struct jpeg_d_coef_controller { long dummy; }; 1107 struct jpeg_d_post_controller { long dummy; }; 1108 struct jpeg_input_controller { long dummy; }; 1109 struct jpeg_marker_reader { long dummy; }; 1110 struct jpeg_entropy_decoder { long dummy; }; 1111 struct jpeg_inverse_dct { long dummy; }; 1112 struct jpeg_upsampler { long dummy; }; 1113 struct jpeg_color_deconverter { long dummy; }; 1114 struct jpeg_color_quantizer { long dummy; }; 1115 #endif /* JPEG_INTERNALS */ 1116 #endif /* INCOMPLETE_TYPES_BROKEN */ 1117 1118 1119 /* 1120 * The JPEG library modules define JPEG_INTERNALS before including this file. 1121 * The internal structure declarations are read only when that is true. 1122 * Applications using the library should not include jpegint.h, but may wish 1123 * to include jerror.h. 1124 */ 1125 1126 #ifdef JPEG_INTERNALS 1127 #include "jpegint.h" /* fetch private declarations */ 1128 #include "jerror.h" /* fetch error codes too */ 1129 #endif 1130 1131 #endif /* JPEGLIB_H */ 1132