1/* 2 * jpeglib.h 3 * 4 * Copyright (C) 1991-1998, Thomas G. Lane. 5 * Modified 2002-2009 by Guido Vollbeding. 6 * This file is part of the Independent JPEG Group's software. 7 * For conditions of distribution and use, see the accompanying README file. 8 * 9 * This file defines the application interface for the JPEG library. 10 * Most applications using the library need only include this file, 11 * and perhaps jerror.h if they want to know the exact error codes. 12 */ 13 14#ifndef JPEGLIB_H 15#define JPEGLIB_H 16 17/* 18 * First we include the configuration files that record how this 19 * installation of the JPEG library is set up. jconfig.h can be 20 * generated automatically for many systems. jmorecfg.h contains 21 * manual configuration options that most people need not worry about. 22 */ 23 24#ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */ 25#include "jconfig.h" /* widely used configuration options */ 26#endif 27#include "jmorecfg.h" /* seldom changed options */ 28 29#ifdef __HAIKU__ 30#include <setjmp.h> 31#endif 32 33#ifdef __cplusplus 34#ifndef DONT_USE_EXTERN_C 35extern "C" { 36#endif 37#endif 38 39/* Version ID for the JPEG library. 40 * Might be useful for tests like "#if JPEG_LIB_VERSION >= 80". 41 */ 42 43#define JPEG_LIB_VERSION 80 /* Version 8.0 */ 44 45 46/* Various constants determining the sizes of things. 47 * All of these are specified by the JPEG standard, so don't change them 48 * if you want to be compatible. 49 */ 50 51#define DCTSIZE 8 /* The basic DCT block is 8x8 samples */ 52#define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */ 53#define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */ 54#define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */ 55#define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */ 56#define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */ 57#define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */ 58/* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard; 59 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU. 60 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU 61 * to handle it. We even let you do this from the jconfig.h file. However, 62 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe 63 * sometimes emits noncompliant files doesn't mean you should too. 64 */ 65#define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */ 66#ifndef D_MAX_BLOCKS_IN_MCU 67#define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */ 68#endif 69 70 71/* Data structures for images (arrays of samples and of DCT coefficients). 72 * On 80x86 machines, the image arrays are too big for near pointers, 73 * but the pointer arrays can fit in near memory. 74 */ 75 76typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */ 77typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ 78typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ 79 80typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ 81typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */ 82typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ 83typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ 84 85typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */ 86 87 88/* Types for JPEG compression parameters and working tables. */ 89 90 91/* DCT coefficient quantization tables. */ 92 93typedef struct { 94 /* This array gives the coefficient quantizers in natural array order 95 * (not the zigzag order in which they are stored in a JPEG DQT marker). 96 * CAUTION: IJG versions prior to v6a kept this array in zigzag order. 97 */ 98 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */ 99 /* This field is used only during compression. It's initialized FALSE when 100 * the table is created, and set TRUE when it's been output to the file. 101 * You could suppress output of a table by setting this to TRUE. 102 * (See jpeg_suppress_tables for an example.) 103 */ 104 boolean sent_table; /* TRUE when table has been output */ 105} JQUANT_TBL; 106 107 108/* Huffman coding tables. */ 109 110typedef struct { 111 /* These two fields directly represent the contents of a JPEG DHT marker */ 112 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ 113 /* length k bits; bits[0] is unused */ 114 UINT8 huffval[256]; /* The symbols, in order of incr code length */ 115 /* This field is used only during compression. It's initialized FALSE when 116 * the table is created, and set TRUE when it's been output to the file. 117 * You could suppress output of a table by setting this to TRUE. 118 * (See jpeg_suppress_tables for an example.) 119 */ 120 boolean sent_table; /* TRUE when table has been output */ 121} JHUFF_TBL; 122 123 124/* Basic info about one component (color channel). */ 125 126typedef struct { 127 /* These values are fixed over the whole image. */ 128 /* For compression, they must be supplied by parameter setup; */ 129 /* for decompression, they are read from the SOF marker. */ 130 int component_id; /* identifier for this component (0..255) */ 131 int component_index; /* its index in SOF or cinfo->comp_info[] */ 132 int h_samp_factor; /* horizontal sampling factor (1..4) */ 133 int v_samp_factor; /* vertical sampling factor (1..4) */ 134 int quant_tbl_no; /* quantization table selector (0..3) */ 135 /* These values may vary between scans. */ 136 /* For compression, they must be supplied by parameter setup; */ 137 /* for decompression, they are read from the SOS marker. */ 138 /* The decompressor output side may not use these variables. */ 139 int dc_tbl_no; /* DC entropy table selector (0..3) */ 140 int ac_tbl_no; /* AC entropy table selector (0..3) */ 141 142 /* Remaining fields should be treated as private by applications. */ 143 144 /* These values are computed during compression or decompression startup: */ 145 /* Component's size in DCT blocks. 146 * Any dummy blocks added to complete an MCU are not counted; therefore 147 * these values do not depend on whether a scan is interleaved or not. 148 */ 149 JDIMENSION width_in_blocks; 150 JDIMENSION height_in_blocks; 151 /* Size of a DCT block in samples, 152 * reflecting any scaling we choose to apply during the DCT step. 153 * Values from 1 to 16 are supported. 154 * Note that different components may receive different DCT scalings. 155 */ 156 int DCT_h_scaled_size; 157 int DCT_v_scaled_size; 158 /* The downsampled dimensions are the component's actual, unpadded number 159 * of samples at the main buffer (preprocessing/compression interface); 160 * DCT scaling is included, so 161 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_h_scaled_size/DCTSIZE) 162 * and similarly for height. 163 */ 164 JDIMENSION downsampled_width; /* actual width in samples */ 165 JDIMENSION downsampled_height; /* actual height in samples */ 166 /* This flag is used only for decompression. In cases where some of the 167 * components will be ignored (eg grayscale output from YCbCr image), 168 * we can skip most computations for the unused components. 169 */ 170 boolean component_needed; /* do we need the value of this component? */ 171 172 /* These values are computed before starting a scan of the component. */ 173 /* The decompressor output side may not use these variables. */ 174 int MCU_width; /* number of blocks per MCU, horizontally */ 175 int MCU_height; /* number of blocks per MCU, vertically */ 176 int MCU_blocks; /* MCU_width * MCU_height */ 177 int MCU_sample_width; /* MCU width in samples: MCU_width * DCT_h_scaled_size */ 178 int last_col_width; /* # of non-dummy blocks across in last MCU */ 179 int last_row_height; /* # of non-dummy blocks down in last MCU */ 180 181 /* Saved quantization table for component; NULL if none yet saved. 182 * See jdinput.c comments about the need for this information. 183 * This field is currently used only for decompression. 184 */ 185 JQUANT_TBL * quant_table; 186 187 /* Private per-component storage for DCT or IDCT subsystem. */ 188 void * dct_table; 189} jpeg_component_info; 190 191 192/* The script for encoding a multiple-scan file is an array of these: */ 193 194typedef struct { 195 int comps_in_scan; /* number of components encoded in this scan */ 196 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */ 197 int Ss, Se; /* progressive JPEG spectral selection parms */ 198 int Ah, Al; /* progressive JPEG successive approx. parms */ 199} jpeg_scan_info; 200 201/* The decompressor can save APPn and COM markers in a list of these: */ 202 203typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr; 204 205struct jpeg_marker_struct { 206 jpeg_saved_marker_ptr next; /* next in list, or NULL */ 207 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */ 208 unsigned int original_length; /* # bytes of data in the file */ 209 unsigned int data_length; /* # bytes of data saved at data[] */ 210 JOCTET FAR * data; /* the data contained in the marker */ 211 /* the marker length word is not counted in data_length or original_length */ 212}; 213 214/* Known color spaces. */ 215 216typedef enum { 217 JCS_UNKNOWN, /* error/unspecified */ 218 JCS_GRAYSCALE, /* monochrome */ 219 JCS_RGB, /* red/green/blue */ 220 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ 221 JCS_CMYK, /* C/M/Y/K */ 222 JCS_YCCK /* Y/Cb/Cr/K */ 223} J_COLOR_SPACE; 224 225/* DCT/IDCT algorithm options. */ 226 227typedef enum { 228 JDCT_ISLOW, /* slow but accurate integer algorithm */ 229 JDCT_IFAST, /* faster, less accurate integer method */ 230 JDCT_FLOAT /* floating-point: accurate, fast on fast HW */ 231} J_DCT_METHOD; 232 233#ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */ 234#define JDCT_DEFAULT JDCT_ISLOW 235#endif 236#ifndef JDCT_FASTEST /* may be overridden in jconfig.h */ 237#define JDCT_FASTEST JDCT_IFAST 238#endif 239 240/* Dithering options for decompression. */ 241 242typedef enum { 243 JDITHER_NONE, /* no dithering */ 244 JDITHER_ORDERED, /* simple ordered dither */ 245 JDITHER_FS /* Floyd-Steinberg error diffusion dither */ 246} J_DITHER_MODE; 247 248 249/* Common fields between JPEG compression and decompression master structs. */ 250 251#define jpeg_common_fields \ 252 struct jpeg_error_mgr * err; /* Error handler module */\ 253 struct jpeg_memory_mgr * mem; /* Memory manager module */\ 254 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\ 255 void * client_data; /* Available for use by application */\ 256 boolean is_decompressor; /* So common code can tell which is which */\ 257 int global_state /* For checking call sequence validity */ 258 259/* Routines that are to be used by both halves of the library are declared 260 * to receive a pointer to this structure. There are no actual instances of 261 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct. 262 */ 263struct jpeg_common_struct { 264 jpeg_common_fields; /* Fields common to both master struct types */ 265 /* Additional fields follow in an actual jpeg_compress_struct or 266 * jpeg_decompress_struct. All three structs must agree on these 267 * initial fields! (This would be a lot cleaner in C++.) 268 */ 269}; 270 271typedef struct jpeg_common_struct * j_common_ptr; 272typedef struct jpeg_compress_struct * j_compress_ptr; 273typedef struct jpeg_decompress_struct * j_decompress_ptr; 274 275 276/* Master record for a compression instance */ 277 278struct jpeg_compress_struct { 279 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */ 280 281 /* Destination for compressed data */ 282 struct jpeg_destination_mgr * dest; 283 284 /* Description of source image --- these fields must be filled in by 285 * outer application before starting compression. in_color_space must 286 * be correct before you can even call jpeg_set_defaults(). 287 */ 288 289 JDIMENSION image_width; /* input image width */ 290 JDIMENSION image_height; /* input image height */ 291 int input_components; /* # of color components in input image */ 292 J_COLOR_SPACE in_color_space; /* colorspace of input image */ 293 294 double input_gamma; /* image gamma of input image */ 295 296 /* Compression parameters --- these fields must be set before calling 297 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to 298 * initialize everything to reasonable defaults, then changing anything 299 * the application specifically wants to change. That way you won't get 300 * burnt when new parameters are added. Also note that there are several 301 * helper routines to simplify changing parameters. 302 */ 303 304 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 305 306 JDIMENSION jpeg_width; /* scaled JPEG image width */ 307 JDIMENSION jpeg_height; /* scaled JPEG image height */ 308 /* Dimensions of actual JPEG image that will be written to file, 309 * derived from input dimensions by scaling factors above. 310 * These fields are computed by jpeg_start_compress(). 311 * You can also use jpeg_calc_jpeg_dimensions() to determine these values 312 * in advance of calling jpeg_start_compress(). 313 */ 314 315 int data_precision; /* bits of precision in image data */ 316 317 int num_components; /* # of color components in JPEG image */ 318 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 319 320 jpeg_component_info * comp_info; 321 /* comp_info[i] describes component that appears i'th in SOF */ 322 323 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 324 int q_scale_factor[NUM_QUANT_TBLS]; 325 /* ptrs to coefficient quantization tables, or NULL if not defined, 326 * and corresponding scale factors (percentage, initialized 100). 327 */ 328 329 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 330 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 331 /* ptrs to Huffman coding tables, or NULL if not defined */ 332 333 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 334 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 335 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 336 337 int num_scans; /* # of entries in scan_info array */ 338 const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */ 339 /* The default value of scan_info is NULL, which causes a single-scan 340 * sequential JPEG file to be emitted. To create a multi-scan file, 341 * set num_scans and scan_info to point to an array of scan definitions. 342 */ 343 344 boolean raw_data_in; /* TRUE=caller supplies downsampled data */ 345 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 346 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ 347 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 348 boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */ 349 int smoothing_factor; /* 1..100, or 0 for no input smoothing */ 350 J_DCT_METHOD dct_method; /* DCT algorithm selector */ 351 352 /* The restart interval can be specified in absolute MCUs by setting 353 * restart_interval, or in MCU rows by setting restart_in_rows 354 * (in which case the correct restart_interval will be figured 355 * for each scan). 356 */ 357 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */ 358 int restart_in_rows; /* if > 0, MCU rows per restart interval */ 359 360 /* Parameters controlling emission of special markers. */ 361 362 boolean write_JFIF_header; /* should a JFIF marker be written? */ 363 UINT8 JFIF_major_version; /* What to write for the JFIF version number */ 364 UINT8 JFIF_minor_version; 365 /* These three values are not used by the JPEG code, merely copied */ 366 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ 367 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ 368 /* ratio is defined by X_density/Y_density even when density_unit=0. */ 369 UINT8 density_unit; /* JFIF code for pixel size units */ 370 UINT16 X_density; /* Horizontal pixel density */ 371 UINT16 Y_density; /* Vertical pixel density */ 372 boolean write_Adobe_marker; /* should an Adobe marker be written? */ 373 374 /* State variable: index of next scanline to be written to 375 * jpeg_write_scanlines(). Application may use this to control its 376 * processing loop, e.g., "while (next_scanline < image_height)". 377 */ 378 379 JDIMENSION next_scanline; /* 0 .. image_height-1 */ 380 381 /* Remaining fields are known throughout compressor, but generally 382 * should not be touched by a surrounding application. 383 */ 384 385 /* 386 * These fields are computed during compression startup 387 */ 388 boolean progressive_mode; /* TRUE if scan script uses progressive mode */ 389 int max_h_samp_factor; /* largest h_samp_factor */ 390 int max_v_samp_factor; /* largest v_samp_factor */ 391 392 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */ 393 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */ 394 395 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */ 396 /* The coefficient controller receives data in units of MCU rows as defined 397 * for fully interleaved scans (whether the JPEG file is interleaved or not). 398 * There are v_samp_factor * DCTSIZE sample rows of each component in an 399 * "iMCU" (interleaved MCU) row. 400 */ 401 402 /* 403 * These fields are valid during any one scan. 404 * They describe the components and MCUs actually appearing in the scan. 405 */ 406 int comps_in_scan; /* # of JPEG components in this scan */ 407 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 408 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 409 410 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 411 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 412 413 int blocks_in_MCU; /* # of DCT blocks per MCU */ 414 int MCU_membership[C_MAX_BLOCKS_IN_MCU]; 415 /* MCU_membership[i] is index in cur_comp_info of component owning */ 416 /* i'th block in an MCU */ 417 418 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */ 419 420 int block_size; /* the basic DCT block size: 1..16 */ 421 const int * natural_order; /* natural-order position array */ 422 int lim_Se; /* min( Se, DCTSIZE2-1 ) */ 423 424 /* 425 * Links to compression subobjects (methods and private variables of modules) 426 */ 427 struct jpeg_comp_master * master; 428 struct jpeg_c_main_controller * main; 429 struct jpeg_c_prep_controller * prep; 430 struct jpeg_c_coef_controller * coef; 431 struct jpeg_marker_writer * marker; 432 struct jpeg_color_converter * cconvert; 433 struct jpeg_downsampler * downsample; 434 struct jpeg_forward_dct * fdct; 435 struct jpeg_entropy_encoder * entropy; 436 jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */ 437 int script_space_size; 438}; 439 440 441/* Master record for a decompression instance */ 442 443struct jpeg_decompress_struct { 444 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */ 445 446 /* Source of compressed data */ 447 struct jpeg_source_mgr * src; 448 449 /* Basic description of image --- filled in by jpeg_read_header(). */ 450 /* Application may inspect these values to decide how to process image. */ 451 452 JDIMENSION image_width; /* nominal image width (from SOF marker) */ 453 JDIMENSION image_height; /* nominal image height */ 454 int num_components; /* # of color components in JPEG image */ 455 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 456 457 /* Decompression processing parameters --- these fields must be set before 458 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes 459 * them to default values. 460 */ 461 462 J_COLOR_SPACE out_color_space; /* colorspace for output */ 463 464 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 465 466 double output_gamma; /* image gamma wanted in output */ 467 468 boolean buffered_image; /* TRUE=multiple output passes */ 469 boolean raw_data_out; /* TRUE=downsampled data wanted */ 470 471 J_DCT_METHOD dct_method; /* IDCT algorithm selector */ 472 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */ 473 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */ 474 475 boolean quantize_colors; /* TRUE=colormapped output wanted */ 476 /* the following are ignored if not quantize_colors: */ 477 J_DITHER_MODE dither_mode; /* type of color dithering to use */ 478 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */ 479 int desired_number_of_colors; /* max # colors to use in created colormap */ 480 /* these are significant only in buffered-image mode: */ 481 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */ 482 boolean enable_external_quant;/* enable future use of external colormap */ 483 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */ 484 485 /* Description of actual output image that will be returned to application. 486 * These fields are computed by jpeg_start_decompress(). 487 * You can also use jpeg_calc_output_dimensions() to determine these values 488 * in advance of calling jpeg_start_decompress(). 489 */ 490 491 JDIMENSION output_width; /* scaled image width */ 492 JDIMENSION output_height; /* scaled image height */ 493 int out_color_components; /* # of color components in out_color_space */ 494 int output_components; /* # of color components returned */ 495 /* output_components is 1 (a colormap index) when quantizing colors; 496 * otherwise it equals out_color_components. 497 */ 498 int rec_outbuf_height; /* min recommended height of scanline buffer */ 499 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows 500 * high, space and time will be wasted due to unnecessary data copying. 501 * Usually rec_outbuf_height will be 1 or 2, at most 4. 502 */ 503 504 /* When quantizing colors, the output colormap is described by these fields. 505 * The application can supply a colormap by setting colormap non-NULL before 506 * calling jpeg_start_decompress; otherwise a colormap is created during 507 * jpeg_start_decompress or jpeg_start_output. 508 * The map has out_color_components rows and actual_number_of_colors columns. 509 */ 510 int actual_number_of_colors; /* number of entries in use */ 511 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */ 512 513 /* State variables: these variables indicate the progress of decompression. 514 * The application may examine these but must not modify them. 515 */ 516 517 /* Row index of next scanline to be read from jpeg_read_scanlines(). 518 * Application may use this to control its processing loop, e.g., 519 * "while (output_scanline < output_height)". 520 */ 521 JDIMENSION output_scanline; /* 0 .. output_height-1 */ 522 523 /* Current input scan number and number of iMCU rows completed in scan. 524 * These indicate the progress of the decompressor input side. 525 */ 526 int input_scan_number; /* Number of SOS markers seen so far */ 527 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */ 528 529 /* The "output scan number" is the notional scan being displayed by the 530 * output side. The decompressor will not allow output scan/row number 531 * to get ahead of input scan/row, but it can fall arbitrarily far behind. 532 */ 533 int output_scan_number; /* Nominal scan number being displayed */ 534 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */ 535 536 /* Current progression status. coef_bits[c][i] indicates the precision 537 * with which component c's DCT coefficient i (in zigzag order) is known. 538 * It is -1 when no data has yet been received, otherwise it is the point 539 * transform (shift) value for the most recent scan of the coefficient 540 * (thus, 0 at completion of the progression). 541 * This pointer is NULL when reading a non-progressive file. 542 */ 543 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */ 544 545 /* Internal JPEG parameters --- the application usually need not look at 546 * these fields. Note that the decompressor output side may not use 547 * any parameters that can change between scans. 548 */ 549 550 /* Quantization and Huffman tables are carried forward across input 551 * datastreams when processing abbreviated JPEG datastreams. 552 */ 553 554 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 555 /* ptrs to coefficient quantization tables, or NULL if not defined */ 556 557 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 558 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 559 /* ptrs to Huffman coding tables, or NULL if not defined */ 560 561 /* These parameters are never carried across datastreams, since they 562 * are given in SOF/SOS markers or defined to be reset by SOI. 563 */ 564 565 int data_precision; /* bits of precision in image data */ 566 567 jpeg_component_info * comp_info; 568 /* comp_info[i] describes component that appears i'th in SOF */ 569 570 boolean is_baseline; /* TRUE if Baseline SOF0 encountered */ 571 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */ 572 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 573 574 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 575 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 576 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 577 578 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */ 579 580 /* These fields record data obtained from optional markers recognized by 581 * the JPEG library. 582 */ 583 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */ 584 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */ 585 UINT8 JFIF_major_version; /* JFIF version number */ 586 UINT8 JFIF_minor_version; 587 UINT8 density_unit; /* JFIF code for pixel size units */ 588 UINT16 X_density; /* Horizontal pixel density */ 589 UINT16 Y_density; /* Vertical pixel density */ 590 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */ 591 UINT8 Adobe_transform; /* Color transform code from Adobe marker */ 592 593 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 594 595 /* Aside from the specific data retained from APPn markers known to the 596 * library, the uninterpreted contents of any or all APPn and COM markers 597 * can be saved in a list for examination by the application. 598 */ 599 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */ 600 601 /* Remaining fields are known throughout decompressor, but generally 602 * should not be touched by a surrounding application. 603 */ 604 605 /* 606 * These fields are computed during decompression startup 607 */ 608 int max_h_samp_factor; /* largest h_samp_factor */ 609 int max_v_samp_factor; /* largest v_samp_factor */ 610 611 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */ 612 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */ 613 614 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ 615 /* The coefficient controller's input and output progress is measured in 616 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows 617 * in fully interleaved JPEG scans, but are used whether the scan is 618 * interleaved or not. We define an iMCU row as v_samp_factor DCT block 619 * rows of each component. Therefore, the IDCT output contains 620 * v_samp_factor*DCT_v_scaled_size sample rows of a component per iMCU row. 621 */ 622 623 JSAMPLE * sample_range_limit; /* table for fast range-limiting */ 624 625 /* 626 * These fields are valid during any one scan. 627 * They describe the components and MCUs actually appearing in the scan. 628 * Note that the decompressor output side must not use these fields. 629 */ 630 int comps_in_scan; /* # of JPEG components in this scan */ 631 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 632 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 633 634 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 635 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 636 637 int blocks_in_MCU; /* # of DCT blocks per MCU */ 638 int MCU_membership[D_MAX_BLOCKS_IN_MCU]; 639 /* MCU_membership[i] is index in cur_comp_info of component owning */ 640 /* i'th block in an MCU */ 641 642 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */ 643 644 /* These fields are derived from Se of first SOS marker. 645 */ 646 int block_size; /* the basic DCT block size: 1..16 */ 647 const int * natural_order; /* natural-order position array for entropy decode */ 648 int lim_Se; /* min( Se, DCTSIZE2-1 ) for entropy decode */ 649 650 /* This field is shared between entropy decoder and marker parser. 651 * It is either zero or the code of a JPEG marker that has been 652 * read from the data source, but has not yet been processed. 653 */ 654 int unread_marker; 655 656 /* 657 * Links to decompression subobjects (methods, private variables of modules) 658 */ 659 struct jpeg_decomp_master * master; 660 struct jpeg_d_main_controller * main; 661 struct jpeg_d_coef_controller * coef; 662 struct jpeg_d_post_controller * post; 663 struct jpeg_input_controller * inputctl; 664 struct jpeg_marker_reader * marker; 665 struct jpeg_entropy_decoder * entropy; 666 struct jpeg_inverse_dct * idct; 667 struct jpeg_upsampler * upsample; 668 struct jpeg_color_deconverter * cconvert; 669 struct jpeg_color_quantizer * cquantize; 670}; 671 672 673/* "Object" declarations for JPEG modules that may be supplied or called 674 * directly by the surrounding application. 675 * As with all objects in the JPEG library, these structs only define the 676 * publicly visible methods and state variables of a module. Additional 677 * private fields may exist after the public ones. 678 */ 679 680 681/* Error handler object */ 682 683struct jpeg_error_mgr { 684 /* Error exit handler: does not return to caller */ 685 JMETHOD(void, error_exit, (j_common_ptr cinfo)); 686 /* Conditionally emit a trace or warning message */ 687 JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level)); 688 /* Routine that actually outputs a trace or error message */ 689 JMETHOD(void, output_message, (j_common_ptr cinfo)); 690 /* Format a message string for the most recent JPEG error or message */ 691 JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer)); 692#define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */ 693 /* Reset error state variables at start of a new image */ 694 JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo)); 695 696 /* The message ID code and any parameters are saved here. 697 * A message can have one string parameter or up to 8 int parameters. 698 */ 699 int msg_code; 700#define JMSG_STR_PARM_MAX 80 701 union { 702 int i[8]; 703 char s[JMSG_STR_PARM_MAX]; 704 } msg_parm; 705 706 /* Standard state variables for error facility */ 707 708 int trace_level; /* max msg_level that will be displayed */ 709 710 /* For recoverable corrupt-data errors, we emit a warning message, 711 * but keep going unless emit_message chooses to abort. emit_message 712 * should count warnings in num_warnings. The surrounding application 713 * can check for bad data by seeing if num_warnings is nonzero at the 714 * end of processing. 715 */ 716 long num_warnings; /* number of corrupt-data warnings */ 717 718 /* These fields point to the table(s) of error message strings. 719 * An application can change the table pointer to switch to a different 720 * message list (typically, to change the language in which errors are 721 * reported). Some applications may wish to add additional error codes 722 * that will be handled by the JPEG library error mechanism; the second 723 * table pointer is used for this purpose. 724 * 725 * First table includes all errors generated by JPEG library itself. 726 * Error code 0 is reserved for a "no such error string" message. 727 */ 728 const char * const * jpeg_message_table; /* Library errors */ 729 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */ 730 /* Second table can be added by application (see cjpeg/djpeg for example). 731 * It contains strings numbered first_addon_message..last_addon_message. 732 */ 733 const char * const * addon_message_table; /* Non-library errors */ 734 int first_addon_message; /* code for first string in addon table */ 735 int last_addon_message; /* code for last string in addon table */ 736 737#ifdef __HAIKU__ 738 jmp_buf long_jump_buffer; 739#endif 740}; 741 742 743/* Progress monitor object */ 744 745struct jpeg_progress_mgr { 746 JMETHOD(void, progress_monitor, (j_common_ptr cinfo)); 747 748 long pass_counter; /* work units completed in this pass */ 749 long pass_limit; /* total number of work units in this pass */ 750 int completed_passes; /* passes completed so far */ 751 int total_passes; /* total number of passes expected */ 752}; 753 754 755/* Data destination object for compression */ 756 757struct jpeg_destination_mgr { 758 JOCTET * next_output_byte; /* => next byte to write in buffer */ 759 size_t free_in_buffer; /* # of byte spaces remaining in buffer */ 760 761 JMETHOD(void, init_destination, (j_compress_ptr cinfo)); 762 JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo)); 763 JMETHOD(void, term_destination, (j_compress_ptr cinfo)); 764}; 765 766 767/* Data source object for decompression */ 768 769struct jpeg_source_mgr { 770 const JOCTET * next_input_byte; /* => next byte to read from buffer */ 771 size_t bytes_in_buffer; /* # of bytes remaining in buffer */ 772 773 JMETHOD(void, init_source, (j_decompress_ptr cinfo)); 774 JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo)); 775 JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes)); 776 JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired)); 777 JMETHOD(void, term_source, (j_decompress_ptr cinfo)); 778}; 779 780 781/* Memory manager object. 782 * Allocates "small" objects (a few K total), "large" objects (tens of K), 783 * and "really big" objects (virtual arrays with backing store if needed). 784 * The memory manager does not allow individual objects to be freed; rather, 785 * each created object is assigned to a pool, and whole pools can be freed 786 * at once. This is faster and more convenient than remembering exactly what 787 * to free, especially where malloc()/free() are not too speedy. 788 * NB: alloc routines never return NULL. They exit to error_exit if not 789 * successful. 790 */ 791 792#define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */ 793#define JPOOL_IMAGE 1 /* lasts until done with image/datastream */ 794#define JPOOL_NUMPOOLS 2 795 796typedef struct jvirt_sarray_control * jvirt_sarray_ptr; 797typedef struct jvirt_barray_control * jvirt_barray_ptr; 798 799 800struct jpeg_memory_mgr { 801 /* Method pointers */ 802 JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id, 803 size_t sizeofobject)); 804 JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id, 805 size_t sizeofobject)); 806 JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id, 807 JDIMENSION samplesperrow, 808 JDIMENSION numrows)); 809 JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id, 810 JDIMENSION blocksperrow, 811 JDIMENSION numrows)); 812 JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo, 813 int pool_id, 814 boolean pre_zero, 815 JDIMENSION samplesperrow, 816 JDIMENSION numrows, 817 JDIMENSION maxaccess)); 818 JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo, 819 int pool_id, 820 boolean pre_zero, 821 JDIMENSION blocksperrow, 822 JDIMENSION numrows, 823 JDIMENSION maxaccess)); 824 JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo)); 825 JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo, 826 jvirt_sarray_ptr ptr, 827 JDIMENSION start_row, 828 JDIMENSION num_rows, 829 boolean writable)); 830 JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo, 831 jvirt_barray_ptr ptr, 832 JDIMENSION start_row, 833 JDIMENSION num_rows, 834 boolean writable)); 835 JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id)); 836 JMETHOD(void, self_destruct, (j_common_ptr cinfo)); 837 838 /* Limit on memory allocation for this JPEG object. (Note that this is 839 * merely advisory, not a guaranteed maximum; it only affects the space 840 * used for virtual-array buffers.) May be changed by outer application 841 * after creating the JPEG object. 842 */ 843 long max_memory_to_use; 844 845 /* Maximum allocation request accepted by alloc_large. */ 846 long max_alloc_chunk; 847}; 848 849 850/* Routine signature for application-supplied marker processing methods. 851 * Need not pass marker code since it is stored in cinfo->unread_marker. 852 */ 853typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo)); 854 855 856/* Declarations for routines called by application. 857 * The JPP macro hides prototype parameters from compilers that can't cope. 858 * Note JPP requires double parentheses. 859 */ 860 861#ifdef HAVE_PROTOTYPES 862#define JPP(arglist) arglist 863#else 864#define JPP(arglist) () 865#endif 866 867 868/* Short forms of external names for systems with brain-damaged linkers. 869 * We shorten external names to be unique in the first six letters, which 870 * is good enough for all known systems. 871 * (If your compiler itself needs names to be unique in less than 15 872 * characters, you are out of luck. Get a better compiler.) 873 */ 874 875#ifdef NEED_SHORT_EXTERNAL_NAMES 876#define jpeg_std_error jStdError 877#define jpeg_CreateCompress jCreaCompress 878#define jpeg_CreateDecompress jCreaDecompress 879#define jpeg_destroy_compress jDestCompress 880#define jpeg_destroy_decompress jDestDecompress 881#define jpeg_stdio_dest jStdDest 882#define jpeg_stdio_src jStdSrc 883#define jpeg_mem_dest jMemDest 884#define jpeg_mem_src jMemSrc 885#define jpeg_set_defaults jSetDefaults 886#define jpeg_set_colorspace jSetColorspace 887#define jpeg_default_colorspace jDefColorspace 888#define jpeg_set_quality jSetQuality 889#define jpeg_set_linear_quality jSetLQuality 890#define jpeg_default_qtables jDefQTables 891#define jpeg_add_quant_table jAddQuantTable 892#define jpeg_quality_scaling jQualityScaling 893#define jpeg_simple_progression jSimProgress 894#define jpeg_suppress_tables jSuppressTables 895#define jpeg_alloc_quant_table jAlcQTable 896#define jpeg_alloc_huff_table jAlcHTable 897#define jpeg_start_compress jStrtCompress 898#define jpeg_write_scanlines jWrtScanlines 899#define jpeg_finish_compress jFinCompress 900#define jpeg_calc_jpeg_dimensions jCjpegDimensions 901#define jpeg_write_raw_data jWrtRawData 902#define jpeg_write_marker jWrtMarker 903#define jpeg_write_m_header jWrtMHeader 904#define jpeg_write_m_byte jWrtMByte 905#define jpeg_write_tables jWrtTables 906#define jpeg_read_header jReadHeader 907#define jpeg_start_decompress jStrtDecompress 908#define jpeg_read_scanlines jReadScanlines 909#define jpeg_finish_decompress jFinDecompress 910#define jpeg_read_raw_data jReadRawData 911#define jpeg_has_multiple_scans jHasMultScn 912#define jpeg_start_output jStrtOutput 913#define jpeg_finish_output jFinOutput 914#define jpeg_input_complete jInComplete 915#define jpeg_new_colormap jNewCMap 916#define jpeg_consume_input jConsumeInput 917#define jpeg_core_output_dimensions jCoreDimensions 918#define jpeg_calc_output_dimensions jCalcDimensions 919#define jpeg_save_markers jSaveMarkers 920#define jpeg_set_marker_processor jSetMarker 921#define jpeg_read_coefficients jReadCoefs 922#define jpeg_write_coefficients jWrtCoefs 923#define jpeg_copy_critical_parameters jCopyCrit 924#define jpeg_abort_compress jAbrtCompress 925#define jpeg_abort_decompress jAbrtDecompress 926#define jpeg_abort jAbort 927#define jpeg_destroy jDestroy 928#define jpeg_resync_to_restart jResyncRestart 929#endif /* NEED_SHORT_EXTERNAL_NAMES */ 930 931 932/* Default error-management setup */ 933EXTERN(struct jpeg_error_mgr *) jpeg_std_error 934 JPP((struct jpeg_error_mgr * err)); 935 936/* Initialization of JPEG compression objects. 937 * jpeg_create_compress() and jpeg_create_decompress() are the exported 938 * names that applications should call. These expand to calls on 939 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information 940 * passed for version mismatch checking. 941 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx. 942 */ 943#define jpeg_create_compress(cinfo) \ 944 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \ 945 (size_t) sizeof(struct jpeg_compress_struct)) 946#define jpeg_create_decompress(cinfo) \ 947 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \ 948 (size_t) sizeof(struct jpeg_decompress_struct)) 949EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo, 950 int version, size_t structsize)); 951EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo, 952 int version, size_t structsize)); 953/* Destruction of JPEG compression objects */ 954EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo)); 955EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo)); 956 957/* Standard data source and destination managers: stdio streams. */ 958/* Caller is responsible for opening the file before and closing after. */ 959EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile)); 960EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile)); 961 962/* Data source and destination managers: memory buffers. */ 963EXTERN(void) jpeg_mem_dest JPP((j_compress_ptr cinfo, 964 unsigned char ** outbuffer, 965 unsigned long * outsize)); 966EXTERN(void) jpeg_mem_src JPP((j_decompress_ptr cinfo, 967 unsigned char * inbuffer, 968 unsigned long insize)); 969 970/* Default parameter setup for compression */ 971EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo)); 972/* Compression parameter setup aids */ 973EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo, 974 J_COLOR_SPACE colorspace)); 975EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo)); 976EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality, 977 boolean force_baseline)); 978EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo, 979 int scale_factor, 980 boolean force_baseline)); 981EXTERN(void) jpeg_default_qtables JPP((j_compress_ptr cinfo, 982 boolean force_baseline)); 983EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl, 984 const unsigned int *basic_table, 985 int scale_factor, 986 boolean force_baseline)); 987EXTERN(int) jpeg_quality_scaling JPP((int quality)); 988EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo)); 989EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo, 990 boolean suppress)); 991EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo)); 992EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo)); 993 994/* Main entry points for compression */ 995EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo, 996 boolean write_all_tables)); 997EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo, 998 JSAMPARRAY scanlines, 999 JDIMENSION num_lines)); 1000EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo)); 1001 1002/* Precalculate JPEG dimensions for current compression parameters. */ 1003EXTERN(void) jpeg_calc_jpeg_dimensions JPP((j_compress_ptr cinfo)); 1004 1005/* Replaces jpeg_write_scanlines when writing raw downsampled data. */ 1006EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo, 1007 JSAMPIMAGE data, 1008 JDIMENSION num_lines)); 1009 1010/* Write a special marker. See libjpeg.txt concerning safe usage. */ 1011EXTERN(void) jpeg_write_marker 1012 JPP((j_compress_ptr cinfo, int marker, 1013 const JOCTET * dataptr, unsigned int datalen)); 1014/* Same, but piecemeal. */ 1015EXTERN(void) jpeg_write_m_header 1016 JPP((j_compress_ptr cinfo, int marker, unsigned int datalen)); 1017EXTERN(void) jpeg_write_m_byte 1018 JPP((j_compress_ptr cinfo, int val)); 1019 1020/* Alternate compression function: just write an abbreviated table file */ 1021EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo)); 1022 1023/* Decompression startup: read start of JPEG datastream to see what's there */ 1024EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo, 1025 boolean require_image)); 1026/* Return value is one of: */ 1027#define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */ 1028#define JPEG_HEADER_OK 1 /* Found valid image datastream */ 1029#define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */ 1030/* If you pass require_image = TRUE (normal case), you need not check for 1031 * a TABLES_ONLY return code; an abbreviated file will cause an error exit. 1032 * JPEG_SUSPENDED is only possible if you use a data source module that can 1033 * give a suspension return (the stdio source module doesn't). 1034 */ 1035 1036/* Main entry points for decompression */ 1037EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo)); 1038EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo, 1039 JSAMPARRAY scanlines, 1040 JDIMENSION max_lines)); 1041EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo)); 1042 1043/* Replaces jpeg_read_scanlines when reading raw downsampled data. */ 1044EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo, 1045 JSAMPIMAGE data, 1046 JDIMENSION max_lines)); 1047 1048/* Additional entry points for buffered-image mode. */ 1049EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo)); 1050EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo, 1051 int scan_number)); 1052EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo)); 1053EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo)); 1054EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo)); 1055EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo)); 1056/* Return value is one of: */ 1057/* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */ 1058#define JPEG_REACHED_SOS 1 /* Reached start of new scan */ 1059#define JPEG_REACHED_EOI 2 /* Reached end of image */ 1060#define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */ 1061#define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */ 1062 1063/* Precalculate output dimensions for current decompression parameters. */ 1064EXTERN(void) jpeg_core_output_dimensions JPP((j_decompress_ptr cinfo)); 1065EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo)); 1066 1067/* Control saving of COM and APPn markers into marker_list. */ 1068EXTERN(void) jpeg_save_markers 1069 JPP((j_decompress_ptr cinfo, int marker_code, 1070 unsigned int length_limit)); 1071 1072/* Install a special processing method for COM or APPn markers. */ 1073EXTERN(void) jpeg_set_marker_processor 1074 JPP((j_decompress_ptr cinfo, int marker_code, 1075 jpeg_marker_parser_method routine)); 1076 1077/* Read or write raw DCT coefficients --- useful for lossless transcoding. */ 1078EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo)); 1079EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo, 1080 jvirt_barray_ptr * coef_arrays)); 1081EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo, 1082 j_compress_ptr dstinfo)); 1083 1084/* If you choose to abort compression or decompression before completing 1085 * jpeg_finish_(de)compress, then you need to clean up to release memory, 1086 * temporary files, etc. You can just call jpeg_destroy_(de)compress 1087 * if you're done with the JPEG object, but if you want to clean it up and 1088 * reuse it, call this: 1089 */ 1090EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo)); 1091EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo)); 1092 1093/* Generic versions of jpeg_abort and jpeg_destroy that work on either 1094 * flavor of JPEG object. These may be more convenient in some places. 1095 */ 1096EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo)); 1097EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo)); 1098 1099/* Default restart-marker-resync procedure for use by data source modules */ 1100EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo, 1101 int desired)); 1102 1103 1104/* These marker codes are exported since applications and data source modules 1105 * are likely to want to use them. 1106 */ 1107 1108#define JPEG_RST0 0xD0 /* RST0 marker code */ 1109#define JPEG_EOI 0xD9 /* EOI marker code */ 1110#define JPEG_APP0 0xE0 /* APP0 marker code */ 1111#define JPEG_COM 0xFE /* COM marker code */ 1112 1113 1114/* If we have a brain-damaged compiler that emits warnings (or worse, errors) 1115 * for structure definitions that are never filled in, keep it quiet by 1116 * supplying dummy definitions for the various substructures. 1117 */ 1118 1119#ifdef INCOMPLETE_TYPES_BROKEN 1120#ifndef JPEG_INTERNALS /* will be defined in jpegint.h */ 1121struct jvirt_sarray_control { long dummy; }; 1122struct jvirt_barray_control { long dummy; }; 1123struct jpeg_comp_master { long dummy; }; 1124struct jpeg_c_main_controller { long dummy; }; 1125struct jpeg_c_prep_controller { long dummy; }; 1126struct jpeg_c_coef_controller { long dummy; }; 1127struct jpeg_marker_writer { long dummy; }; 1128struct jpeg_color_converter { long dummy; }; 1129struct jpeg_downsampler { long dummy; }; 1130struct jpeg_forward_dct { long dummy; }; 1131struct jpeg_entropy_encoder { long dummy; }; 1132struct jpeg_decomp_master { long dummy; }; 1133struct jpeg_d_main_controller { long dummy; }; 1134struct jpeg_d_coef_controller { long dummy; }; 1135struct jpeg_d_post_controller { long dummy; }; 1136struct jpeg_input_controller { long dummy; }; 1137struct jpeg_marker_reader { long dummy; }; 1138struct jpeg_entropy_decoder { long dummy; }; 1139struct jpeg_inverse_dct { long dummy; }; 1140struct jpeg_upsampler { long dummy; }; 1141struct jpeg_color_deconverter { long dummy; }; 1142struct jpeg_color_quantizer { long dummy; }; 1143#endif /* JPEG_INTERNALS */ 1144#endif /* INCOMPLETE_TYPES_BROKEN */ 1145 1146 1147/* 1148 * The JPEG library modules define JPEG_INTERNALS before including this file. 1149 * The internal structure declarations are read only when that is true. 1150 * Applications using the library should not include jpegint.h, but may wish 1151 * to include jerror.h. 1152 */ 1153 1154#ifdef JPEG_INTERNALS 1155#include "jpegint.h" /* fetch private declarations */ 1156#include "jerror.h" /* fetch error codes too */ 1157#endif 1158 1159#ifdef __cplusplus 1160#ifndef DONT_USE_EXTERN_C 1161} 1162#endif 1163#endif 1164 1165#endif /* JPEGLIB_H */ 1166