1 /* 2 * jpeglib.h 3 * 4 * This file was part of the Independent JPEG Group's software: 5 * Copyright (C) 1991-1998, Thomas G. Lane. 6 * Modified 2002-2009 by Guido Vollbeding. 7 * libjpeg-turbo Modifications: 8 * Copyright (C) 2009-2011, 2013-2014, 2016-2017, 2020, D. R. Commander. 9 * Copyright (C) 2015, Google, Inc. 10 * For conditions of distribution and use, see the accompanying README.ijg 11 * file. 12 * 13 * This file defines the application interface for the JPEG library. 14 * Most applications using the library need only include this file, 15 * and perhaps jerror.h if they want to know the exact error codes. 16 */ 17 18 #ifndef JPEGLIB_H 19 #define JPEGLIB_H 20 21 /* Begin chromium edits */ 22 #ifdef MANGLE_JPEG_NAMES 23 #include "jpeglibmangler.h" 24 #endif 25 /* End chromium edits */ 26 27 /* 28 * First we include the configuration files that record how this 29 * installation of the JPEG library is set up. jconfig.h can be 30 * generated automatically for many systems. jmorecfg.h contains 31 * manual configuration options that most people need not worry about. 32 */ 33 34 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */ 35 #include "jconfig.h" /* widely used configuration options */ 36 #endif 37 #include "jmorecfg.h" /* seldom changed options */ 38 39 40 #ifdef __cplusplus 41 #ifndef DONT_USE_EXTERN_C 42 extern "C" { 43 #endif 44 #endif 45 46 47 /* Various constants determining the sizes of things. 48 * All of these are specified by the JPEG standard, so don't change them 49 * if you want to be compatible. 50 */ 51 52 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */ 53 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */ 54 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */ 55 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */ 56 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */ 57 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */ 58 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */ 59 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard; 60 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU. 61 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU 62 * to handle it. We even let you do this from the jconfig.h file. However, 63 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe 64 * sometimes emits noncompliant files doesn't mean you should too. 65 */ 66 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */ 67 #ifndef D_MAX_BLOCKS_IN_MCU 68 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */ 69 #endif 70 71 72 /* Data structures for images (arrays of samples and of DCT coefficients). 73 */ 74 75 typedef JSAMPLE *JSAMPROW; /* ptr to one image row of pixel samples. */ 76 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ 77 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ 78 79 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ 80 typedef JBLOCK *JBLOCKROW; /* pointer to one row of coefficient blocks */ 81 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ 82 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ 83 84 typedef JCOEF *JCOEFPTR; /* useful in a couple of places */ 85 86 87 /* Types for JPEG compression parameters and working tables. */ 88 89 90 /* DCT coefficient quantization tables. */ 91 92 typedef struct { 93 /* This array gives the coefficient quantizers in natural array order 94 * (not the zigzag order in which they are stored in a JPEG DQT marker). 95 * CAUTION: IJG versions prior to v6a kept this array in zigzag order. 96 */ 97 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */ 98 /* This field is used only during compression. It's initialized FALSE when 99 * the table is created, and set TRUE when it's been output to the file. 100 * You could suppress output of a table by setting this to TRUE. 101 * (See jpeg_suppress_tables for an example.) 102 */ 103 boolean sent_table; /* TRUE when table has been output */ 104 } JQUANT_TBL; 105 106 107 /* Huffman coding tables. */ 108 109 typedef struct { 110 /* These two fields directly represent the contents of a JPEG DHT marker */ 111 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ 112 /* length k bits; bits[0] is unused */ 113 UINT8 huffval[256]; /* The symbols, in order of incr code length */ 114 /* This field is used only during compression. It's initialized FALSE when 115 * the table is created, and set TRUE when it's been output to the file. 116 * You could suppress output of a table by setting this to TRUE. 117 * (See jpeg_suppress_tables for an example.) 118 */ 119 boolean sent_table; /* TRUE when table has been output */ 120 } JHUFF_TBL; 121 122 123 /* Basic info about one component (color channel). */ 124 125 typedef struct { 126 /* These values are fixed over the whole image. */ 127 /* For compression, they must be supplied by parameter setup; */ 128 /* for decompression, they are read from the SOF marker. */ 129 int component_id; /* identifier for this component (0..255) */ 130 int component_index; /* its index in SOF or cinfo->comp_info[] */ 131 int h_samp_factor; /* horizontal sampling factor (1..4) */ 132 int v_samp_factor; /* vertical sampling factor (1..4) */ 133 int quant_tbl_no; /* quantization table selector (0..3) */ 134 /* These values may vary between scans. */ 135 /* For compression, they must be supplied by parameter setup; */ 136 /* for decompression, they are read from the SOS marker. */ 137 /* The decompressor output side may not use these variables. */ 138 int dc_tbl_no; /* DC entropy table selector (0..3) */ 139 int ac_tbl_no; /* AC entropy table selector (0..3) */ 140 141 /* Remaining fields should be treated as private by applications. */ 142 143 /* These values are computed during compression or decompression startup: */ 144 /* Component's size in DCT blocks. 145 * Any dummy blocks added to complete an MCU are not counted; therefore 146 * these values do not depend on whether a scan is interleaved or not. 147 */ 148 JDIMENSION width_in_blocks; 149 JDIMENSION height_in_blocks; 150 /* Size of a DCT block in samples. Always DCTSIZE for compression. 151 * For decompression this is the size of the output from one DCT block, 152 * reflecting any scaling we choose to apply during the IDCT step. 153 * Values from 1 to 16 are supported. 154 * Note that different components may receive different IDCT scalings. 155 */ 156 #if JPEG_LIB_VERSION >= 70 157 int DCT_h_scaled_size; 158 int DCT_v_scaled_size; 159 #else 160 int DCT_scaled_size; 161 #endif 162 /* The downsampled dimensions are the component's actual, unpadded number 163 * of samples at the main buffer (preprocessing/compression interface), thus 164 * downsampled_width = ceil(image_width * Hi/Hmax) 165 * and similarly for height. For decompression, IDCT scaling is included, so 166 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_[h_]scaled_size/DCTSIZE) 167 */ 168 JDIMENSION downsampled_width; /* actual width in samples */ 169 JDIMENSION downsampled_height; /* actual height in samples */ 170 /* This flag is used only for decompression. In cases where some of the 171 * components will be ignored (eg grayscale output from YCbCr image), 172 * we can skip most computations for the unused components. 173 */ 174 boolean component_needed; /* do we need the value of this component? */ 175 176 /* These values are computed before starting a scan of the component. */ 177 /* The decompressor output side may not use these variables. */ 178 int MCU_width; /* number of blocks per MCU, horizontally */ 179 int MCU_height; /* number of blocks per MCU, vertically */ 180 int MCU_blocks; /* MCU_width * MCU_height */ 181 int MCU_sample_width; /* MCU width in samples, MCU_width*DCT_[h_]scaled_size */ 182 int last_col_width; /* # of non-dummy blocks across in last MCU */ 183 int last_row_height; /* # of non-dummy blocks down in last MCU */ 184 185 /* Saved quantization table for component; NULL if none yet saved. 186 * See jdinput.c comments about the need for this information. 187 * This field is currently used only for decompression. 188 */ 189 JQUANT_TBL *quant_table; 190 191 /* Private per-component storage for DCT or IDCT subsystem. */ 192 void *dct_table; 193 } jpeg_component_info; 194 195 196 /* The script for encoding a multiple-scan file is an array of these: */ 197 198 typedef struct { 199 int comps_in_scan; /* number of components encoded in this scan */ 200 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */ 201 int Ss, Se; /* progressive JPEG spectral selection parms */ 202 int Ah, Al; /* progressive JPEG successive approx. parms */ 203 } jpeg_scan_info; 204 205 /* The decompressor can save APPn and COM markers in a list of these: */ 206 207 typedef struct jpeg_marker_struct *jpeg_saved_marker_ptr; 208 209 struct jpeg_marker_struct { 210 jpeg_saved_marker_ptr next; /* next in list, or NULL */ 211 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */ 212 unsigned int original_length; /* # bytes of data in the file */ 213 unsigned int data_length; /* # bytes of data saved at data[] */ 214 JOCTET *data; /* the data contained in the marker */ 215 /* the marker length word is not counted in data_length or original_length */ 216 }; 217 218 /* Known color spaces. */ 219 220 #define JCS_EXTENSIONS 1 221 #define JCS_ALPHA_EXTENSIONS 1 222 223 typedef enum { 224 JCS_UNKNOWN, /* error/unspecified */ 225 JCS_GRAYSCALE, /* monochrome */ 226 JCS_RGB, /* red/green/blue as specified by the RGB_RED, 227 RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros */ 228 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ 229 JCS_CMYK, /* C/M/Y/K */ 230 JCS_YCCK, /* Y/Cb/Cr/K */ 231 JCS_EXT_RGB, /* red/green/blue */ 232 JCS_EXT_RGBX, /* red/green/blue/x */ 233 JCS_EXT_BGR, /* blue/green/red */ 234 JCS_EXT_BGRX, /* blue/green/red/x */ 235 JCS_EXT_XBGR, /* x/blue/green/red */ 236 JCS_EXT_XRGB, /* x/red/green/blue */ 237 /* When out_color_space it set to JCS_EXT_RGBX, JCS_EXT_BGRX, JCS_EXT_XBGR, 238 or JCS_EXT_XRGB during decompression, the X byte is undefined, and in 239 order to ensure the best performance, libjpeg-turbo can set that byte to 240 whatever value it wishes. Use the following colorspace constants to 241 ensure that the X byte is set to 0xFF, so that it can be interpreted as an 242 opaque alpha channel. */ 243 JCS_EXT_RGBA, /* red/green/blue/alpha */ 244 JCS_EXT_BGRA, /* blue/green/red/alpha */ 245 JCS_EXT_ABGR, /* alpha/blue/green/red */ 246 JCS_EXT_ARGB, /* alpha/red/green/blue */ 247 JCS_RGB565 /* 5-bit red/6-bit green/5-bit blue */ 248 } J_COLOR_SPACE; 249 250 /* DCT/IDCT algorithm options. */ 251 252 typedef enum { 253 JDCT_ISLOW, /* accurate integer method */ 254 JDCT_IFAST, /* less accurate integer method [legacy feature] */ 255 JDCT_FLOAT /* floating-point method [legacy feature] */ 256 } J_DCT_METHOD; 257 258 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */ 259 #define JDCT_DEFAULT JDCT_ISLOW 260 #endif 261 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */ 262 #define JDCT_FASTEST JDCT_IFAST 263 #endif 264 265 /* Dithering options for decompression. */ 266 267 typedef enum { 268 JDITHER_NONE, /* no dithering */ 269 JDITHER_ORDERED, /* simple ordered dither */ 270 JDITHER_FS /* Floyd-Steinberg error diffusion dither */ 271 } J_DITHER_MODE; 272 273 274 /* Common fields between JPEG compression and decompression master structs. */ 275 276 #define jpeg_common_fields \ 277 struct jpeg_error_mgr *err; /* Error handler module */ \ 278 struct jpeg_memory_mgr *mem; /* Memory manager module */ \ 279 struct jpeg_progress_mgr *progress; /* Progress monitor, or NULL if none */ \ 280 void *client_data; /* Available for use by application */ \ 281 boolean is_decompressor; /* So common code can tell which is which */ \ 282 int global_state /* For checking call sequence validity */ 283 284 /* Routines that are to be used by both halves of the library are declared 285 * to receive a pointer to this structure. There are no actual instances of 286 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct. 287 */ 288 struct jpeg_common_struct { 289 jpeg_common_fields; /* Fields common to both master struct types */ 290 /* Additional fields follow in an actual jpeg_compress_struct or 291 * jpeg_decompress_struct. All three structs must agree on these 292 * initial fields! (This would be a lot cleaner in C++.) 293 */ 294 }; 295 296 typedef struct jpeg_common_struct *j_common_ptr; 297 typedef struct jpeg_compress_struct *j_compress_ptr; 298 typedef struct jpeg_decompress_struct *j_decompress_ptr; 299 300 301 /* Master record for a compression instance */ 302 303 struct jpeg_compress_struct { 304 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */ 305 306 /* Destination for compressed data */ 307 struct jpeg_destination_mgr *dest; 308 309 /* Description of source image --- these fields must be filled in by 310 * outer application before starting compression. in_color_space must 311 * be correct before you can even call jpeg_set_defaults(). 312 */ 313 314 JDIMENSION image_width; /* input image width */ 315 JDIMENSION image_height; /* input image height */ 316 int input_components; /* # of color components in input image */ 317 J_COLOR_SPACE in_color_space; /* colorspace of input image */ 318 319 double input_gamma; /* image gamma of input image */ 320 321 /* Compression parameters --- these fields must be set before calling 322 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to 323 * initialize everything to reasonable defaults, then changing anything 324 * the application specifically wants to change. That way you won't get 325 * burnt when new parameters are added. Also note that there are several 326 * helper routines to simplify changing parameters. 327 */ 328 329 #if JPEG_LIB_VERSION >= 70 330 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 331 332 JDIMENSION jpeg_width; /* scaled JPEG image width */ 333 JDIMENSION jpeg_height; /* scaled JPEG image height */ 334 /* Dimensions of actual JPEG image that will be written to file, 335 * derived from input dimensions by scaling factors above. 336 * These fields are computed by jpeg_start_compress(). 337 * You can also use jpeg_calc_jpeg_dimensions() to determine these values 338 * in advance of calling jpeg_start_compress(). 339 */ 340 #endif 341 342 int data_precision; /* bits of precision in image data */ 343 344 int num_components; /* # of color components in JPEG image */ 345 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 346 347 jpeg_component_info *comp_info; 348 /* comp_info[i] describes component that appears i'th in SOF */ 349 350 JQUANT_TBL *quant_tbl_ptrs[NUM_QUANT_TBLS]; 351 #if JPEG_LIB_VERSION >= 70 352 int q_scale_factor[NUM_QUANT_TBLS]; 353 #endif 354 /* ptrs to coefficient quantization tables, or NULL if not defined, 355 * and corresponding scale factors (percentage, initialized 100). 356 */ 357 358 JHUFF_TBL *dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 359 JHUFF_TBL *ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 360 /* ptrs to Huffman coding tables, or NULL if not defined */ 361 362 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 363 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 364 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 365 366 int num_scans; /* # of entries in scan_info array */ 367 const jpeg_scan_info *scan_info; /* script for multi-scan file, or NULL */ 368 /* The default value of scan_info is NULL, which causes a single-scan 369 * sequential JPEG file to be emitted. To create a multi-scan file, 370 * set num_scans and scan_info to point to an array of scan definitions. 371 */ 372 373 boolean raw_data_in; /* TRUE=caller supplies downsampled data */ 374 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 375 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ 376 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 377 #if JPEG_LIB_VERSION >= 70 378 boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */ 379 #endif 380 int smoothing_factor; /* 1..100, or 0 for no input smoothing */ 381 J_DCT_METHOD dct_method; /* DCT algorithm selector */ 382 383 /* The restart interval can be specified in absolute MCUs by setting 384 * restart_interval, or in MCU rows by setting restart_in_rows 385 * (in which case the correct restart_interval will be figured 386 * for each scan). 387 */ 388 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */ 389 int restart_in_rows; /* if > 0, MCU rows per restart interval */ 390 391 /* Parameters controlling emission of special markers. */ 392 393 boolean write_JFIF_header; /* should a JFIF marker be written? */ 394 UINT8 JFIF_major_version; /* What to write for the JFIF version number */ 395 UINT8 JFIF_minor_version; 396 /* These three values are not used by the JPEG code, merely copied */ 397 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ 398 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ 399 /* ratio is defined by X_density/Y_density even when density_unit=0. */ 400 UINT8 density_unit; /* JFIF code for pixel size units */ 401 UINT16 X_density; /* Horizontal pixel density */ 402 UINT16 Y_density; /* Vertical pixel density */ 403 boolean write_Adobe_marker; /* should an Adobe marker be written? */ 404 405 /* State variable: index of next scanline to be written to 406 * jpeg_write_scanlines(). Application may use this to control its 407 * processing loop, e.g., "while (next_scanline < image_height)". 408 */ 409 410 JDIMENSION next_scanline; /* 0 .. image_height-1 */ 411 412 /* Remaining fields are known throughout compressor, but generally 413 * should not be touched by a surrounding application. 414 */ 415 416 /* 417 * These fields are computed during compression startup 418 */ 419 boolean progressive_mode; /* TRUE if scan script uses progressive mode */ 420 int max_h_samp_factor; /* largest h_samp_factor */ 421 int max_v_samp_factor; /* largest v_samp_factor */ 422 423 #if JPEG_LIB_VERSION >= 70 424 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */ 425 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */ 426 #endif 427 428 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */ 429 /* The coefficient controller receives data in units of MCU rows as defined 430 * for fully interleaved scans (whether the JPEG file is interleaved or not). 431 * There are v_samp_factor * DCTSIZE sample rows of each component in an 432 * "iMCU" (interleaved MCU) row. 433 */ 434 435 /* 436 * These fields are valid during any one scan. 437 * They describe the components and MCUs actually appearing in the scan. 438 */ 439 int comps_in_scan; /* # of JPEG components in this scan */ 440 jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN]; 441 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 442 443 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 444 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 445 446 int blocks_in_MCU; /* # of DCT blocks per MCU */ 447 int MCU_membership[C_MAX_BLOCKS_IN_MCU]; 448 /* MCU_membership[i] is index in cur_comp_info of component owning */ 449 /* i'th block in an MCU */ 450 451 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */ 452 453 #if JPEG_LIB_VERSION >= 80 454 int block_size; /* the basic DCT block size: 1..16 */ 455 const int *natural_order; /* natural-order position array */ 456 int lim_Se; /* min( Se, DCTSIZE2-1 ) */ 457 #endif 458 459 /* 460 * Links to compression subobjects (methods and private variables of modules) 461 */ 462 struct jpeg_comp_master *master; 463 struct jpeg_c_main_controller *main; 464 struct jpeg_c_prep_controller *prep; 465 struct jpeg_c_coef_controller *coef; 466 struct jpeg_marker_writer *marker; 467 struct jpeg_color_converter *cconvert; 468 struct jpeg_downsampler *downsample; 469 struct jpeg_forward_dct *fdct; 470 struct jpeg_entropy_encoder *entropy; 471 jpeg_scan_info *script_space; /* workspace for jpeg_simple_progression */ 472 int script_space_size; 473 }; 474 475 476 /* Master record for a decompression instance */ 477 478 struct jpeg_decompress_struct { 479 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */ 480 481 /* Source of compressed data */ 482 struct jpeg_source_mgr *src; 483 484 /* Basic description of image --- filled in by jpeg_read_header(). */ 485 /* Application may inspect these values to decide how to process image. */ 486 487 JDIMENSION image_width; /* nominal image width (from SOF marker) */ 488 JDIMENSION image_height; /* nominal image height */ 489 int num_components; /* # of color components in JPEG image */ 490 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 491 492 /* Decompression processing parameters --- these fields must be set before 493 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes 494 * them to default values. 495 */ 496 497 J_COLOR_SPACE out_color_space; /* colorspace for output */ 498 499 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 500 501 double output_gamma; /* image gamma wanted in output */ 502 503 boolean buffered_image; /* TRUE=multiple output passes */ 504 boolean raw_data_out; /* TRUE=downsampled data wanted */ 505 506 J_DCT_METHOD dct_method; /* IDCT algorithm selector */ 507 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */ 508 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */ 509 510 boolean quantize_colors; /* TRUE=colormapped output wanted */ 511 /* the following are ignored if not quantize_colors: */ 512 J_DITHER_MODE dither_mode; /* type of color dithering to use */ 513 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */ 514 int desired_number_of_colors; /* max # colors to use in created colormap */ 515 /* these are significant only in buffered-image mode: */ 516 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */ 517 boolean enable_external_quant;/* enable future use of external colormap */ 518 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */ 519 520 /* Description of actual output image that will be returned to application. 521 * These fields are computed by jpeg_start_decompress(). 522 * You can also use jpeg_calc_output_dimensions() to determine these values 523 * in advance of calling jpeg_start_decompress(). 524 */ 525 526 JDIMENSION output_width; /* scaled image width */ 527 JDIMENSION output_height; /* scaled image height */ 528 int out_color_components; /* # of color components in out_color_space */ 529 int output_components; /* # of color components returned */ 530 /* output_components is 1 (a colormap index) when quantizing colors; 531 * otherwise it equals out_color_components. 532 */ 533 int rec_outbuf_height; /* min recommended height of scanline buffer */ 534 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows 535 * high, space and time will be wasted due to unnecessary data copying. 536 * Usually rec_outbuf_height will be 1 or 2, at most 4. 537 */ 538 539 /* When quantizing colors, the output colormap is described by these fields. 540 * The application can supply a colormap by setting colormap non-NULL before 541 * calling jpeg_start_decompress; otherwise a colormap is created during 542 * jpeg_start_decompress or jpeg_start_output. 543 * The map has out_color_components rows and actual_number_of_colors columns. 544 */ 545 int actual_number_of_colors; /* number of entries in use */ 546 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */ 547 548 /* State variables: these variables indicate the progress of decompression. 549 * The application may examine these but must not modify them. 550 */ 551 552 /* Row index of next scanline to be read from jpeg_read_scanlines(). 553 * Application may use this to control its processing loop, e.g., 554 * "while (output_scanline < output_height)". 555 */ 556 JDIMENSION output_scanline; /* 0 .. output_height-1 */ 557 558 /* Current input scan number and number of iMCU rows completed in scan. 559 * These indicate the progress of the decompressor input side. 560 */ 561 int input_scan_number; /* Number of SOS markers seen so far */ 562 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */ 563 564 /* The "output scan number" is the notional scan being displayed by the 565 * output side. The decompressor will not allow output scan/row number 566 * to get ahead of input scan/row, but it can fall arbitrarily far behind. 567 */ 568 int output_scan_number; /* Nominal scan number being displayed */ 569 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */ 570 571 /* Current progression status. coef_bits[c][i] indicates the precision 572 * with which component c's DCT coefficient i (in zigzag order) is known. 573 * It is -1 when no data has yet been received, otherwise it is the point 574 * transform (shift) value for the most recent scan of the coefficient 575 * (thus, 0 at completion of the progression). 576 * This pointer is NULL when reading a non-progressive file. 577 */ 578 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */ 579 580 /* Internal JPEG parameters --- the application usually need not look at 581 * these fields. Note that the decompressor output side may not use 582 * any parameters that can change between scans. 583 */ 584 585 /* Quantization and Huffman tables are carried forward across input 586 * datastreams when processing abbreviated JPEG datastreams. 587 */ 588 589 JQUANT_TBL *quant_tbl_ptrs[NUM_QUANT_TBLS]; 590 /* ptrs to coefficient quantization tables, or NULL if not defined */ 591 592 JHUFF_TBL *dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 593 JHUFF_TBL *ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 594 /* ptrs to Huffman coding tables, or NULL if not defined */ 595 596 /* These parameters are never carried across datastreams, since they 597 * are given in SOF/SOS markers or defined to be reset by SOI. 598 */ 599 600 int data_precision; /* bits of precision in image data */ 601 602 jpeg_component_info *comp_info; 603 /* comp_info[i] describes component that appears i'th in SOF */ 604 605 #if JPEG_LIB_VERSION >= 80 606 boolean is_baseline; /* TRUE if Baseline SOF0 encountered */ 607 #endif 608 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */ 609 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 610 611 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 612 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 613 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 614 615 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */ 616 617 /* These fields record data obtained from optional markers recognized by 618 * the JPEG library. 619 */ 620 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */ 621 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */ 622 UINT8 JFIF_major_version; /* JFIF version number */ 623 UINT8 JFIF_minor_version; 624 UINT8 density_unit; /* JFIF code for pixel size units */ 625 UINT16 X_density; /* Horizontal pixel density */ 626 UINT16 Y_density; /* Vertical pixel density */ 627 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */ 628 UINT8 Adobe_transform; /* Color transform code from Adobe marker */ 629 630 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 631 632 /* Aside from the specific data retained from APPn markers known to the 633 * library, the uninterpreted contents of any or all APPn and COM markers 634 * can be saved in a list for examination by the application. 635 */ 636 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */ 637 638 /* Remaining fields are known throughout decompressor, but generally 639 * should not be touched by a surrounding application. 640 */ 641 642 /* 643 * These fields are computed during decompression startup 644 */ 645 int max_h_samp_factor; /* largest h_samp_factor */ 646 int max_v_samp_factor; /* largest v_samp_factor */ 647 648 #if JPEG_LIB_VERSION >= 70 649 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */ 650 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */ 651 #else 652 int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */ 653 #endif 654 655 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ 656 /* The coefficient controller's input and output progress is measured in 657 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows 658 * in fully interleaved JPEG scans, but are used whether the scan is 659 * interleaved or not. We define an iMCU row as v_samp_factor DCT block 660 * rows of each component. Therefore, the IDCT output contains 661 * v_samp_factor*DCT_[v_]scaled_size sample rows of a component per iMCU row. 662 */ 663 664 JSAMPLE *sample_range_limit; /* table for fast range-limiting */ 665 666 /* 667 * These fields are valid during any one scan. 668 * They describe the components and MCUs actually appearing in the scan. 669 * Note that the decompressor output side must not use these fields. 670 */ 671 int comps_in_scan; /* # of JPEG components in this scan */ 672 jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN]; 673 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 674 675 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 676 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 677 678 int blocks_in_MCU; /* # of DCT blocks per MCU */ 679 int MCU_membership[D_MAX_BLOCKS_IN_MCU]; 680 /* MCU_membership[i] is index in cur_comp_info of component owning */ 681 /* i'th block in an MCU */ 682 683 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */ 684 685 #if JPEG_LIB_VERSION >= 80 686 /* These fields are derived from Se of first SOS marker. 687 */ 688 int block_size; /* the basic DCT block size: 1..16 */ 689 const int *natural_order; /* natural-order position array for entropy decode */ 690 int lim_Se; /* min( Se, DCTSIZE2-1 ) for entropy decode */ 691 #endif 692 693 /* This field is shared between entropy decoder and marker parser. 694 * It is either zero or the code of a JPEG marker that has been 695 * read from the data source, but has not yet been processed. 696 */ 697 int unread_marker; 698 699 /* 700 * Links to decompression subobjects (methods, private variables of modules) 701 */ 702 struct jpeg_decomp_master *master; 703 struct jpeg_d_main_controller *main; 704 struct jpeg_d_coef_controller *coef; 705 struct jpeg_d_post_controller *post; 706 struct jpeg_input_controller *inputctl; 707 struct jpeg_marker_reader *marker; 708 struct jpeg_entropy_decoder *entropy; 709 struct jpeg_inverse_dct *idct; 710 struct jpeg_upsampler *upsample; 711 struct jpeg_color_deconverter *cconvert; 712 struct jpeg_color_quantizer *cquantize; 713 }; 714 715 716 /* "Object" declarations for JPEG modules that may be supplied or called 717 * directly by the surrounding application. 718 * As with all objects in the JPEG library, these structs only define the 719 * publicly visible methods and state variables of a module. Additional 720 * private fields may exist after the public ones. 721 */ 722 723 724 /* Error handler object */ 725 726 struct jpeg_error_mgr { 727 /* Error exit handler: does not return to caller */ 728 void (*error_exit) (j_common_ptr cinfo); 729 /* Conditionally emit a trace or warning message */ 730 void (*emit_message) (j_common_ptr cinfo, int msg_level); 731 /* Routine that actually outputs a trace or error message */ 732 void (*output_message) (j_common_ptr cinfo); 733 /* Format a message string for the most recent JPEG error or message */ 734 void (*format_message) (j_common_ptr cinfo, char *buffer); 735 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */ 736 /* Reset error state variables at start of a new image */ 737 void (*reset_error_mgr) (j_common_ptr cinfo); 738 739 /* The message ID code and any parameters are saved here. 740 * A message can have one string parameter or up to 8 int parameters. 741 */ 742 int msg_code; 743 #define JMSG_STR_PARM_MAX 80 744 union { 745 int i[8]; 746 char s[JMSG_STR_PARM_MAX]; 747 } msg_parm; 748 749 /* Standard state variables for error facility */ 750 751 int trace_level; /* max msg_level that will be displayed */ 752 753 /* For recoverable corrupt-data errors, we emit a warning message, 754 * but keep going unless emit_message chooses to abort. emit_message 755 * should count warnings in num_warnings. The surrounding application 756 * can check for bad data by seeing if num_warnings is nonzero at the 757 * end of processing. 758 */ 759 long num_warnings; /* number of corrupt-data warnings */ 760 761 /* These fields point to the table(s) of error message strings. 762 * An application can change the table pointer to switch to a different 763 * message list (typically, to change the language in which errors are 764 * reported). Some applications may wish to add additional error codes 765 * that will be handled by the JPEG library error mechanism; the second 766 * table pointer is used for this purpose. 767 * 768 * First table includes all errors generated by JPEG library itself. 769 * Error code 0 is reserved for a "no such error string" message. 770 */ 771 const char * const *jpeg_message_table; /* Library errors */ 772 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */ 773 /* Second table can be added by application (see cjpeg/djpeg for example). 774 * It contains strings numbered first_addon_message..last_addon_message. 775 */ 776 const char * const *addon_message_table; /* Non-library errors */ 777 int first_addon_message; /* code for first string in addon table */ 778 int last_addon_message; /* code for last string in addon table */ 779 }; 780 781 782 /* Progress monitor object */ 783 784 struct jpeg_progress_mgr { 785 void (*progress_monitor) (j_common_ptr cinfo); 786 787 long pass_counter; /* work units completed in this pass */ 788 long pass_limit; /* total number of work units in this pass */ 789 int completed_passes; /* passes completed so far */ 790 int total_passes; /* total number of passes expected */ 791 }; 792 793 794 /* Data destination object for compression */ 795 796 struct jpeg_destination_mgr { 797 JOCTET *next_output_byte; /* => next byte to write in buffer */ 798 size_t free_in_buffer; /* # of byte spaces remaining in buffer */ 799 800 void (*init_destination) (j_compress_ptr cinfo); 801 boolean (*empty_output_buffer) (j_compress_ptr cinfo); 802 void (*term_destination) (j_compress_ptr cinfo); 803 }; 804 805 806 /* Data source object for decompression */ 807 808 struct jpeg_source_mgr { 809 const JOCTET *next_input_byte; /* => next byte to read from buffer */ 810 size_t bytes_in_buffer; /* # of bytes remaining in buffer */ 811 812 void (*init_source) (j_decompress_ptr cinfo); 813 boolean (*fill_input_buffer) (j_decompress_ptr cinfo); 814 void (*skip_input_data) (j_decompress_ptr cinfo, long num_bytes); 815 boolean (*resync_to_restart) (j_decompress_ptr cinfo, int desired); 816 void (*term_source) (j_decompress_ptr cinfo); 817 }; 818 819 820 /* Memory manager object. 821 * Allocates "small" objects (a few K total), "large" objects (tens of K), 822 * and "really big" objects (virtual arrays with backing store if needed). 823 * The memory manager does not allow individual objects to be freed; rather, 824 * each created object is assigned to a pool, and whole pools can be freed 825 * at once. This is faster and more convenient than remembering exactly what 826 * to free, especially where malloc()/free() are not too speedy. 827 * NB: alloc routines never return NULL. They exit to error_exit if not 828 * successful. 829 */ 830 831 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */ 832 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */ 833 #define JPOOL_NUMPOOLS 2 834 835 typedef struct jvirt_sarray_control *jvirt_sarray_ptr; 836 typedef struct jvirt_barray_control *jvirt_barray_ptr; 837 838 839 struct jpeg_memory_mgr { 840 /* Method pointers */ 841 void *(*alloc_small) (j_common_ptr cinfo, int pool_id, size_t sizeofobject); 842 void *(*alloc_large) (j_common_ptr cinfo, int pool_id, 843 size_t sizeofobject); 844 JSAMPARRAY (*alloc_sarray) (j_common_ptr cinfo, int pool_id, 845 JDIMENSION samplesperrow, JDIMENSION numrows); 846 JBLOCKARRAY (*alloc_barray) (j_common_ptr cinfo, int pool_id, 847 JDIMENSION blocksperrow, JDIMENSION numrows); 848 jvirt_sarray_ptr (*request_virt_sarray) (j_common_ptr cinfo, int pool_id, 849 boolean pre_zero, 850 JDIMENSION samplesperrow, 851 JDIMENSION numrows, 852 JDIMENSION maxaccess); 853 jvirt_barray_ptr (*request_virt_barray) (j_common_ptr cinfo, int pool_id, 854 boolean pre_zero, 855 JDIMENSION blocksperrow, 856 JDIMENSION numrows, 857 JDIMENSION maxaccess); 858 void (*realize_virt_arrays) (j_common_ptr cinfo); 859 JSAMPARRAY (*access_virt_sarray) (j_common_ptr cinfo, jvirt_sarray_ptr ptr, 860 JDIMENSION start_row, JDIMENSION num_rows, 861 boolean writable); 862 JBLOCKARRAY (*access_virt_barray) (j_common_ptr cinfo, jvirt_barray_ptr ptr, 863 JDIMENSION start_row, JDIMENSION num_rows, 864 boolean writable); 865 void (*free_pool) (j_common_ptr cinfo, int pool_id); 866 void (*self_destruct) (j_common_ptr cinfo); 867 868 /* Limit on memory allocation for this JPEG object. (Note that this is 869 * merely advisory, not a guaranteed maximum; it only affects the space 870 * used for virtual-array buffers.) May be changed by outer application 871 * after creating the JPEG object. 872 */ 873 long max_memory_to_use; 874 875 /* Maximum allocation request accepted by alloc_large. */ 876 long max_alloc_chunk; 877 }; 878 879 880 /* Routine signature for application-supplied marker processing methods. 881 * Need not pass marker code since it is stored in cinfo->unread_marker. 882 */ 883 typedef boolean (*jpeg_marker_parser_method) (j_decompress_ptr cinfo); 884 885 886 /* Originally, this macro was used as a way of defining function prototypes 887 * for both modern compilers as well as older compilers that did not support 888 * prototype parameters. libjpeg-turbo has never supported these older, 889 * non-ANSI compilers, but the macro is still included because there is some 890 * software out there that uses it. 891 */ 892 893 #define JPP(arglist) arglist 894 895 896 /* Default error-management setup */ 897 EXTERN(struct jpeg_error_mgr *) jpeg_std_error(struct jpeg_error_mgr *err); 898 899 /* Initialization of JPEG compression objects. 900 * jpeg_create_compress() and jpeg_create_decompress() are the exported 901 * names that applications should call. These expand to calls on 902 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information 903 * passed for version mismatch checking. 904 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx. 905 */ 906 #define jpeg_create_compress(cinfo) \ 907 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \ 908 (size_t)sizeof(struct jpeg_compress_struct)) 909 #define jpeg_create_decompress(cinfo) \ 910 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \ 911 (size_t)sizeof(struct jpeg_decompress_struct)) 912 EXTERN(void) jpeg_CreateCompress(j_compress_ptr cinfo, int version, 913 size_t structsize); 914 EXTERN(void) jpeg_CreateDecompress(j_decompress_ptr cinfo, int version, 915 size_t structsize); 916 /* Destruction of JPEG compression objects */ 917 EXTERN(void) jpeg_destroy_compress(j_compress_ptr cinfo); 918 EXTERN(void) jpeg_destroy_decompress(j_decompress_ptr cinfo); 919 920 /* Standard data source and destination managers: stdio streams. */ 921 /* Caller is responsible for opening the file before and closing after. */ 922 EXTERN(void) jpeg_stdio_dest(j_compress_ptr cinfo, FILE *outfile); 923 EXTERN(void) jpeg_stdio_src(j_decompress_ptr cinfo, FILE *infile); 924 925 #if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED) 926 /* Data source and destination managers: memory buffers. */ 927 EXTERN(void) jpeg_mem_dest(j_compress_ptr cinfo, unsigned char **outbuffer, 928 unsigned long *outsize); 929 EXTERN(void) jpeg_mem_src(j_decompress_ptr cinfo, 930 const unsigned char *inbuffer, unsigned long insize); 931 #endif 932 933 /* Default parameter setup for compression */ 934 EXTERN(void) jpeg_set_defaults(j_compress_ptr cinfo); 935 /* Compression parameter setup aids */ 936 EXTERN(void) jpeg_set_colorspace(j_compress_ptr cinfo, 937 J_COLOR_SPACE colorspace); 938 EXTERN(void) jpeg_default_colorspace(j_compress_ptr cinfo); 939 EXTERN(void) jpeg_set_quality(j_compress_ptr cinfo, int quality, 940 boolean force_baseline); 941 EXTERN(void) jpeg_set_linear_quality(j_compress_ptr cinfo, int scale_factor, 942 boolean force_baseline); 943 #if JPEG_LIB_VERSION >= 70 944 EXTERN(void) jpeg_default_qtables(j_compress_ptr cinfo, 945 boolean force_baseline); 946 #endif 947 EXTERN(void) jpeg_add_quant_table(j_compress_ptr cinfo, int which_tbl, 948 const unsigned int *basic_table, 949 int scale_factor, boolean force_baseline); 950 EXTERN(int) jpeg_quality_scaling(int quality); 951 EXTERN(void) jpeg_simple_progression(j_compress_ptr cinfo); 952 EXTERN(void) jpeg_suppress_tables(j_compress_ptr cinfo, boolean suppress); 953 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table(j_common_ptr cinfo); 954 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table(j_common_ptr cinfo); 955 956 /* Main entry points for compression */ 957 EXTERN(void) jpeg_start_compress(j_compress_ptr cinfo, 958 boolean write_all_tables); 959 EXTERN(JDIMENSION) jpeg_write_scanlines(j_compress_ptr cinfo, 960 JSAMPARRAY scanlines, 961 JDIMENSION num_lines); 962 EXTERN(void) jpeg_finish_compress(j_compress_ptr cinfo); 963 964 #if JPEG_LIB_VERSION >= 70 965 /* Precalculate JPEG dimensions for current compression parameters. */ 966 EXTERN(void) jpeg_calc_jpeg_dimensions(j_compress_ptr cinfo); 967 #endif 968 969 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */ 970 EXTERN(JDIMENSION) jpeg_write_raw_data(j_compress_ptr cinfo, JSAMPIMAGE data, 971 JDIMENSION num_lines); 972 973 /* Write a special marker. See libjpeg.txt concerning safe usage. */ 974 EXTERN(void) jpeg_write_marker(j_compress_ptr cinfo, int marker, 975 const JOCTET *dataptr, unsigned int datalen); 976 /* Same, but piecemeal. */ 977 EXTERN(void) jpeg_write_m_header(j_compress_ptr cinfo, int marker, 978 unsigned int datalen); 979 EXTERN(void) jpeg_write_m_byte(j_compress_ptr cinfo, int val); 980 981 /* Alternate compression function: just write an abbreviated table file */ 982 EXTERN(void) jpeg_write_tables(j_compress_ptr cinfo); 983 984 /* Write ICC profile. See libjpeg.txt for usage information. */ 985 EXTERN(void) jpeg_write_icc_profile(j_compress_ptr cinfo, 986 const JOCTET *icc_data_ptr, 987 unsigned int icc_data_len); 988 989 990 /* Decompression startup: read start of JPEG datastream to see what's there */ 991 EXTERN(int) jpeg_read_header(j_decompress_ptr cinfo, boolean require_image); 992 /* Return value is one of: */ 993 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */ 994 #define JPEG_HEADER_OK 1 /* Found valid image datastream */ 995 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */ 996 /* If you pass require_image = TRUE (normal case), you need not check for 997 * a TABLES_ONLY return code; an abbreviated file will cause an error exit. 998 * JPEG_SUSPENDED is only possible if you use a data source module that can 999 * give a suspension return (the stdio source module doesn't). 1000 */ 1001 1002 /* Main entry points for decompression */ 1003 EXTERN(boolean) jpeg_start_decompress(j_decompress_ptr cinfo); 1004 EXTERN(JDIMENSION) jpeg_read_scanlines(j_decompress_ptr cinfo, 1005 JSAMPARRAY scanlines, 1006 JDIMENSION max_lines); 1007 EXTERN(JDIMENSION) jpeg_skip_scanlines(j_decompress_ptr cinfo, 1008 JDIMENSION num_lines); 1009 EXTERN(void) jpeg_crop_scanline(j_decompress_ptr cinfo, JDIMENSION *xoffset, 1010 JDIMENSION *width); 1011 EXTERN(boolean) jpeg_finish_decompress(j_decompress_ptr cinfo); 1012 1013 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */ 1014 EXTERN(JDIMENSION) jpeg_read_raw_data(j_decompress_ptr cinfo, JSAMPIMAGE data, 1015 JDIMENSION max_lines); 1016 1017 /* Additional entry points for buffered-image mode. */ 1018 EXTERN(boolean) jpeg_has_multiple_scans(j_decompress_ptr cinfo); 1019 EXTERN(boolean) jpeg_start_output(j_decompress_ptr cinfo, int scan_number); 1020 EXTERN(boolean) jpeg_finish_output(j_decompress_ptr cinfo); 1021 EXTERN(boolean) jpeg_input_complete(j_decompress_ptr cinfo); 1022 EXTERN(void) jpeg_new_colormap(j_decompress_ptr cinfo); 1023 EXTERN(int) jpeg_consume_input(j_decompress_ptr cinfo); 1024 /* Return value is one of: */ 1025 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */ 1026 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */ 1027 #define JPEG_REACHED_EOI 2 /* Reached end of image */ 1028 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */ 1029 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */ 1030 1031 /* Precalculate output dimensions for current decompression parameters. */ 1032 #if JPEG_LIB_VERSION >= 80 1033 EXTERN(void) jpeg_core_output_dimensions(j_decompress_ptr cinfo); 1034 #endif 1035 EXTERN(void) jpeg_calc_output_dimensions(j_decompress_ptr cinfo); 1036 1037 /* Control saving of COM and APPn markers into marker_list. */ 1038 EXTERN(void) jpeg_save_markers(j_decompress_ptr cinfo, int marker_code, 1039 unsigned int length_limit); 1040 1041 /* Install a special processing method for COM or APPn markers. */ 1042 EXTERN(void) jpeg_set_marker_processor(j_decompress_ptr cinfo, 1043 int marker_code, 1044 jpeg_marker_parser_method routine); 1045 1046 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */ 1047 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients(j_decompress_ptr cinfo); 1048 EXTERN(void) jpeg_write_coefficients(j_compress_ptr cinfo, 1049 jvirt_barray_ptr *coef_arrays); 1050 EXTERN(void) jpeg_copy_critical_parameters(j_decompress_ptr srcinfo, 1051 j_compress_ptr dstinfo); 1052 1053 /* If you choose to abort compression or decompression before completing 1054 * jpeg_finish_(de)compress, then you need to clean up to release memory, 1055 * temporary files, etc. You can just call jpeg_destroy_(de)compress 1056 * if you're done with the JPEG object, but if you want to clean it up and 1057 * reuse it, call this: 1058 */ 1059 EXTERN(void) jpeg_abort_compress(j_compress_ptr cinfo); 1060 EXTERN(void) jpeg_abort_decompress(j_decompress_ptr cinfo); 1061 1062 /* Generic versions of jpeg_abort and jpeg_destroy that work on either 1063 * flavor of JPEG object. These may be more convenient in some places. 1064 */ 1065 EXTERN(void) jpeg_abort(j_common_ptr cinfo); 1066 EXTERN(void) jpeg_destroy(j_common_ptr cinfo); 1067 1068 /* Default restart-marker-resync procedure for use by data source modules */ 1069 EXTERN(boolean) jpeg_resync_to_restart(j_decompress_ptr cinfo, int desired); 1070 1071 /* Read ICC profile. See libjpeg.txt for usage information. */ 1072 EXTERN(boolean) jpeg_read_icc_profile(j_decompress_ptr cinfo, 1073 JOCTET **icc_data_ptr, 1074 unsigned int *icc_data_len); 1075 1076 1077 /* These marker codes are exported since applications and data source modules 1078 * are likely to want to use them. 1079 */ 1080 1081 #define JPEG_RST0 0xD0 /* RST0 marker code */ 1082 #define JPEG_EOI 0xD9 /* EOI marker code */ 1083 #define JPEG_APP0 0xE0 /* APP0 marker code */ 1084 #define JPEG_COM 0xFE /* COM marker code */ 1085 1086 1087 /* If we have a brain-damaged compiler that emits warnings (or worse, errors) 1088 * for structure definitions that are never filled in, keep it quiet by 1089 * supplying dummy definitions for the various substructures. 1090 */ 1091 1092 #ifdef INCOMPLETE_TYPES_BROKEN 1093 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */ 1094 struct jvirt_sarray_control { long dummy; }; 1095 struct jvirt_barray_control { long dummy; }; 1096 struct jpeg_comp_master { long dummy; }; 1097 struct jpeg_c_main_controller { long dummy; }; 1098 struct jpeg_c_prep_controller { long dummy; }; 1099 struct jpeg_c_coef_controller { long dummy; }; 1100 struct jpeg_marker_writer { long dummy; }; 1101 struct jpeg_color_converter { long dummy; }; 1102 struct jpeg_downsampler { long dummy; }; 1103 struct jpeg_forward_dct { long dummy; }; 1104 struct jpeg_entropy_encoder { long dummy; }; 1105 struct jpeg_decomp_master { long dummy; }; 1106 struct jpeg_d_main_controller { long dummy; }; 1107 struct jpeg_d_coef_controller { long dummy; }; 1108 struct jpeg_d_post_controller { long dummy; }; 1109 struct jpeg_input_controller { long dummy; }; 1110 struct jpeg_marker_reader { long dummy; }; 1111 struct jpeg_entropy_decoder { long dummy; }; 1112 struct jpeg_inverse_dct { long dummy; }; 1113 struct jpeg_upsampler { long dummy; }; 1114 struct jpeg_color_deconverter { long dummy; }; 1115 struct jpeg_color_quantizer { long dummy; }; 1116 #endif /* JPEG_INTERNALS */ 1117 #endif /* INCOMPLETE_TYPES_BROKEN */ 1118 1119 1120 /* 1121 * The JPEG library modules define JPEG_INTERNALS before including this file. 1122 * The internal structure declarations are read only when that is true. 1123 * Applications using the library should not include jpegint.h, but may wish 1124 * to include jerror.h. 1125 */ 1126 1127 #ifdef JPEG_INTERNALS 1128 #include "jpegint.h" /* fetch private declarations */ 1129 #include "jerror.h" /* fetch error codes too */ 1130 #endif 1131 1132 #ifdef __cplusplus 1133 #ifndef DONT_USE_EXTERN_C 1134 } 1135 #endif 1136 #endif 1137 1138 #endif /* JPEGLIB_H */ 1139