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 * Modifications: 8 * Copyright (C) 2009-2011, 2013, D. R. Commander. 9 * For conditions of distribution and use, see the accompanying README file. 10 * 11 * This file defines the application interface for the JPEG library. 12 * Most applications using the library need only include this file, 13 * and perhaps jerror.h if they want to know the exact error codes. 14 */ 15 16 #ifndef JPEGLIB_H 17 #define JPEGLIB_H 18 19 /* Begin chromium edits */ 20 #include "jpeglibmangler.h" 21 /* End chromium edits */ 22 23 /* 24 * First we include the configuration files that record how this 25 * installation of the JPEG library is set up. jconfig.h can be 26 * generated automatically for many systems. jmorecfg.h contains 27 * manual configuration options that most people need not worry about. 28 */ 29 30 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */ 31 #include "jconfig.h" /* widely used configuration options */ 32 #endif 33 #include "jmorecfg.h" /* seldom changed options */ 34 35 36 #ifdef __cplusplus 37 #ifndef DONT_USE_EXTERN_C 38 extern "C" { 39 #endif 40 #endif 41 42 43 /* Various constants determining the sizes of things. 44 * All of these are specified by the JPEG standard, so don't change them 45 * if you want to be compatible. 46 */ 47 48 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */ 49 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */ 50 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */ 51 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */ 52 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */ 53 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */ 54 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */ 55 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard; 56 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU. 57 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU 58 * to handle it. We even let you do this from the jconfig.h file. However, 59 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe 60 * sometimes emits noncompliant files doesn't mean you should too. 61 */ 62 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */ 63 #ifndef D_MAX_BLOCKS_IN_MCU 64 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */ 65 #endif 66 67 68 /* Data structures for images (arrays of samples and of DCT coefficients). 69 * On 80x86 machines, the image arrays are too big for near pointers, 70 * but the pointer arrays can fit in near memory. 71 */ 72 73 typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */ 74 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ 75 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ 76 77 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ 78 typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */ 79 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ 80 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ 81 82 typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */ 83 84 85 /* Types for JPEG compression parameters and working tables. */ 86 87 88 /* DCT coefficient quantization tables. */ 89 90 typedef struct { 91 /* This array gives the coefficient quantizers in natural array order 92 * (not the zigzag order in which they are stored in a JPEG DQT marker). 93 * CAUTION: IJG versions prior to v6a kept this array in zigzag order. 94 */ 95 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */ 96 /* This field is used only during compression. It's initialized FALSE when 97 * the table is created, and set TRUE when it's been output to the file. 98 * You could suppress output of a table by setting this to TRUE. 99 * (See jpeg_suppress_tables for an example.) 100 */ 101 boolean sent_table; /* TRUE when table has been output */ 102 } JQUANT_TBL; 103 104 105 /* Huffman coding tables. */ 106 107 typedef struct { 108 /* These two fields directly represent the contents of a JPEG DHT marker */ 109 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ 110 /* length k bits; bits[0] is unused */ 111 UINT8 huffval[256]; /* The symbols, in order of incr code length */ 112 /* This field is used only during compression. It's initialized FALSE when 113 * the table is created, and set TRUE when it's been output to the file. 114 * You could suppress output of a table by setting this to TRUE. 115 * (See jpeg_suppress_tables for an example.) 116 */ 117 boolean sent_table; /* TRUE when table has been output */ 118 } JHUFF_TBL; 119 120 121 /* Basic info about one component (color channel). */ 122 123 typedef struct { 124 /* These values are fixed over the whole image. */ 125 /* For compression, they must be supplied by parameter setup; */ 126 /* for decompression, they are read from the SOF marker. */ 127 int component_id; /* identifier for this component (0..255) */ 128 int component_index; /* its index in SOF or cinfo->comp_info[] */ 129 int h_samp_factor; /* horizontal sampling factor (1..4) */ 130 int v_samp_factor; /* vertical sampling factor (1..4) */ 131 int quant_tbl_no; /* quantization table selector (0..3) */ 132 /* These values may vary between scans. */ 133 /* For compression, they must be supplied by parameter setup; */ 134 /* for decompression, they are read from the SOS marker. */ 135 /* The decompressor output side may not use these variables. */ 136 int dc_tbl_no; /* DC entropy table selector (0..3) */ 137 int ac_tbl_no; /* AC entropy table selector (0..3) */ 138 139 /* Remaining fields should be treated as private by applications. */ 140 141 /* These values are computed during compression or decompression startup: */ 142 /* Component's size in DCT blocks. 143 * Any dummy blocks added to complete an MCU are not counted; therefore 144 * these values do not depend on whether a scan is interleaved or not. 145 */ 146 JDIMENSION width_in_blocks; 147 JDIMENSION height_in_blocks; 148 /* Size of a DCT block in samples. Always DCTSIZE for compression. 149 * For decompression this is the size of the output from one DCT block, 150 * reflecting any scaling we choose to apply during the IDCT step. 151 * Values of 1,2,4,8 are likely to be supported. Note that different 152 * components may receive different IDCT scalings. 153 */ 154 #if JPEG_LIB_VERSION >= 70 155 int DCT_h_scaled_size; 156 int DCT_v_scaled_size; 157 #else 158 int DCT_scaled_size; 159 #endif 160 /* The downsampled dimensions are the component's actual, unpadded number 161 * of samples at the main buffer (preprocessing/compression interface), thus 162 * downsampled_width = ceil(image_width * Hi/Hmax) 163 * and similarly for height. For decompression, IDCT scaling is included, so 164 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_[h_]scaled_size/DCTSIZE) 165 */ 166 JDIMENSION downsampled_width; /* actual width in samples */ 167 JDIMENSION downsampled_height; /* actual height in samples */ 168 /* This flag is used only for decompression. In cases where some of the 169 * components will be ignored (eg grayscale output from YCbCr image), 170 * we can skip most computations for the unused components. 171 */ 172 boolean component_needed; /* do we need the value of this component? */ 173 174 /* These values are computed before starting a scan of the component. */ 175 /* The decompressor output side may not use these variables. */ 176 int MCU_width; /* number of blocks per MCU, horizontally */ 177 int MCU_height; /* number of blocks per MCU, vertically */ 178 int MCU_blocks; /* MCU_width * MCU_height */ 179 int MCU_sample_width; /* MCU width in samples, MCU_width*DCT_[h_]scaled_size */ 180 int last_col_width; /* # of non-dummy blocks across in last MCU */ 181 int last_row_height; /* # of non-dummy blocks down in last MCU */ 182 183 /* Saved quantization table for component; NULL if none yet saved. 184 * See jdinput.c comments about the need for this information. 185 * This field is currently used only for decompression. 186 */ 187 JQUANT_TBL * quant_table; 188 189 /* Private per-component storage for DCT or IDCT subsystem. */ 190 void * dct_table; 191 } jpeg_component_info; 192 193 194 /* The script for encoding a multiple-scan file is an array of these: */ 195 196 typedef struct { 197 int comps_in_scan; /* number of components encoded in this scan */ 198 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */ 199 int Ss, Se; /* progressive JPEG spectral selection parms */ 200 int Ah, Al; /* progressive JPEG successive approx. parms */ 201 } jpeg_scan_info; 202 203 /* The decompressor can save APPn and COM markers in a list of these: */ 204 205 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr; 206 207 struct jpeg_marker_struct { 208 jpeg_saved_marker_ptr next; /* next in list, or NULL */ 209 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */ 210 unsigned int original_length; /* # bytes of data in the file */ 211 unsigned int data_length; /* # bytes of data saved at data[] */ 212 JOCTET FAR * data; /* the data contained in the marker */ 213 /* the marker length word is not counted in data_length or original_length */ 214 }; 215 216 /* Known color spaces. */ 217 218 #define JCS_EXTENSIONS 1 219 #define JCS_ALPHA_EXTENSIONS 1 220 221 typedef enum { 222 JCS_UNKNOWN, /* error/unspecified */ 223 JCS_GRAYSCALE, /* monochrome */ 224 JCS_RGB, /* red/green/blue as specified by the RGB_RED, RGB_GREEN, 225 RGB_BLUE, and RGB_PIXELSIZE macros */ 226 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ 227 JCS_CMYK, /* C/M/Y/K */ 228 JCS_YCCK, /* Y/Cb/Cr/K */ 229 JCS_EXT_RGB, /* red/green/blue */ 230 JCS_EXT_RGBX, /* red/green/blue/x */ 231 JCS_EXT_BGR, /* blue/green/red */ 232 JCS_EXT_BGRX, /* blue/green/red/x */ 233 JCS_EXT_XBGR, /* x/blue/green/red */ 234 JCS_EXT_XRGB, /* x/red/green/blue */ 235 /* When out_color_space it set to JCS_EXT_RGBX, JCS_EXT_BGRX, 236 JCS_EXT_XBGR, or JCS_EXT_XRGB during decompression, the X byte is 237 undefined, and in order to ensure the best performance, 238 libjpeg-turbo can set that byte to whatever value it wishes. Use 239 the following colorspace constants to ensure that the X byte is set 240 to 0xFF, so that it can be interpreted as an opaque alpha 241 channel. */ 242 JCS_EXT_RGBA, /* red/green/blue/alpha */ 243 JCS_EXT_BGRA, /* blue/green/red/alpha */ 244 JCS_EXT_ABGR, /* alpha/blue/green/red */ 245 JCS_EXT_ARGB /* alpha/red/green/blue */ 246 } J_COLOR_SPACE; 247 248 /* DCT/IDCT algorithm options. */ 249 250 typedef enum { 251 JDCT_ISLOW, /* slow but accurate integer algorithm */ 252 JDCT_IFAST, /* faster, less accurate integer method */ 253 JDCT_FLOAT /* floating-point: accurate, fast on fast HW */ 254 } J_DCT_METHOD; 255 256 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */ 257 #define JDCT_DEFAULT JDCT_ISLOW 258 #endif 259 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */ 260 #define JDCT_FASTEST JDCT_IFAST 261 #endif 262 263 /* Dithering options for decompression. */ 264 265 typedef enum { 266 JDITHER_NONE, /* no dithering */ 267 JDITHER_ORDERED, /* simple ordered dither */ 268 JDITHER_FS /* Floyd-Steinberg error diffusion dither */ 269 } J_DITHER_MODE; 270 271 272 /* Common fields between JPEG compression and decompression master structs. */ 273 274 #define jpeg_common_fields \ 275 struct jpeg_error_mgr * err; /* Error handler module */\ 276 struct jpeg_memory_mgr * mem; /* Memory manager module */\ 277 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\ 278 void * client_data; /* Available for use by application */\ 279 boolean is_decompressor; /* So common code can tell which is which */\ 280 int global_state /* For checking call sequence validity */ 281 282 /* Routines that are to be used by both halves of the library are declared 283 * to receive a pointer to this structure. There are no actual instances of 284 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct. 285 */ 286 struct jpeg_common_struct { 287 jpeg_common_fields; /* Fields common to both master struct types */ 288 /* Additional fields follow in an actual jpeg_compress_struct or 289 * jpeg_decompress_struct. All three structs must agree on these 290 * initial fields! (This would be a lot cleaner in C++.) 291 */ 292 }; 293 294 typedef struct jpeg_common_struct * j_common_ptr; 295 typedef struct jpeg_compress_struct * j_compress_ptr; 296 typedef struct jpeg_decompress_struct * j_decompress_ptr; 297 298 299 /* Master record for a compression instance */ 300 301 struct jpeg_compress_struct { 302 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */ 303 304 /* Destination for compressed data */ 305 struct jpeg_destination_mgr * dest; 306 307 /* Description of source image --- these fields must be filled in by 308 * outer application before starting compression. in_color_space must 309 * be correct before you can even call jpeg_set_defaults(). 310 */ 311 312 JDIMENSION image_width; /* input image width */ 313 JDIMENSION image_height; /* input image height */ 314 int input_components; /* # of color components in input image */ 315 J_COLOR_SPACE in_color_space; /* colorspace of input image */ 316 317 double input_gamma; /* image gamma of input image */ 318 319 /* Compression parameters --- these fields must be set before calling 320 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to 321 * initialize everything to reasonable defaults, then changing anything 322 * the application specifically wants to change. That way you won't get 323 * burnt when new parameters are added. Also note that there are several 324 * helper routines to simplify changing parameters. 325 */ 326 327 #if JPEG_LIB_VERSION >= 70 328 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 329 330 JDIMENSION jpeg_width; /* scaled JPEG image width */ 331 JDIMENSION jpeg_height; /* scaled JPEG image height */ 332 /* Dimensions of actual JPEG image that will be written to file, 333 * derived from input dimensions by scaling factors above. 334 * These fields are computed by jpeg_start_compress(). 335 * You can also use jpeg_calc_jpeg_dimensions() to determine these values 336 * in advance of calling jpeg_start_compress(). 337 */ 338 #endif 339 340 int data_precision; /* bits of precision in image data */ 341 342 int num_components; /* # of color components in JPEG image */ 343 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 344 345 jpeg_component_info * comp_info; 346 /* comp_info[i] describes component that appears i'th in SOF */ 347 348 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 349 #if JPEG_LIB_VERSION >= 70 350 int q_scale_factor[NUM_QUANT_TBLS]; 351 #endif 352 /* ptrs to coefficient quantization tables, or NULL if not defined, 353 * and corresponding scale factors (percentage, initialized 100). 354 */ 355 356 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 357 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 358 /* ptrs to Huffman coding tables, or NULL if not defined */ 359 360 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 361 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 362 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 363 364 int num_scans; /* # of entries in scan_info array */ 365 const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */ 366 /* The default value of scan_info is NULL, which causes a single-scan 367 * sequential JPEG file to be emitted. To create a multi-scan file, 368 * set num_scans and scan_info to point to an array of scan definitions. 369 */ 370 371 boolean raw_data_in; /* TRUE=caller supplies downsampled data */ 372 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 373 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ 374 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 375 #if JPEG_LIB_VERSION >= 70 376 boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */ 377 #endif 378 int smoothing_factor; /* 1..100, or 0 for no input smoothing */ 379 J_DCT_METHOD dct_method; /* DCT algorithm selector */ 380 381 /* The restart interval can be specified in absolute MCUs by setting 382 * restart_interval, or in MCU rows by setting restart_in_rows 383 * (in which case the correct restart_interval will be figured 384 * for each scan). 385 */ 386 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */ 387 int restart_in_rows; /* if > 0, MCU rows per restart interval */ 388 389 /* Parameters controlling emission of special markers. */ 390 391 boolean write_JFIF_header; /* should a JFIF marker be written? */ 392 UINT8 JFIF_major_version; /* What to write for the JFIF version number */ 393 UINT8 JFIF_minor_version; 394 /* These three values are not used by the JPEG code, merely copied */ 395 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ 396 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ 397 /* ratio is defined by X_density/Y_density even when density_unit=0. */ 398 UINT8 density_unit; /* JFIF code for pixel size units */ 399 UINT16 X_density; /* Horizontal pixel density */ 400 UINT16 Y_density; /* Vertical pixel density */ 401 boolean write_Adobe_marker; /* should an Adobe marker be written? */ 402 403 /* State variable: index of next scanline to be written to 404 * jpeg_write_scanlines(). Application may use this to control its 405 * processing loop, e.g., "while (next_scanline < image_height)". 406 */ 407 408 JDIMENSION next_scanline; /* 0 .. image_height-1 */ 409 410 /* Remaining fields are known throughout compressor, but generally 411 * should not be touched by a surrounding application. 412 */ 413 414 /* 415 * These fields are computed during compression startup 416 */ 417 boolean progressive_mode; /* TRUE if scan script uses progressive mode */ 418 int max_h_samp_factor; /* largest h_samp_factor */ 419 int max_v_samp_factor; /* largest v_samp_factor */ 420 421 #if JPEG_LIB_VERSION >= 70 422 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */ 423 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */ 424 #endif 425 426 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */ 427 /* The coefficient controller receives data in units of MCU rows as defined 428 * for fully interleaved scans (whether the JPEG file is interleaved or not). 429 * There are v_samp_factor * DCTSIZE sample rows of each component in an 430 * "iMCU" (interleaved MCU) row. 431 */ 432 433 /* 434 * These fields are valid during any one scan. 435 * They describe the components and MCUs actually appearing in the scan. 436 */ 437 int comps_in_scan; /* # of JPEG components in this scan */ 438 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 439 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 440 441 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 442 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 443 444 int blocks_in_MCU; /* # of DCT blocks per MCU */ 445 int MCU_membership[C_MAX_BLOCKS_IN_MCU]; 446 /* MCU_membership[i] is index in cur_comp_info of component owning */ 447 /* i'th block in an MCU */ 448 449 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */ 450 451 #if JPEG_LIB_VERSION >= 80 452 int block_size; /* the basic DCT block size: 1..16 */ 453 const int * natural_order; /* natural-order position array */ 454 int lim_Se; /* min( Se, DCTSIZE2-1 ) */ 455 #endif 456 457 /* 458 * Links to compression subobjects (methods and private variables of modules) 459 */ 460 struct jpeg_comp_master * master; 461 struct jpeg_c_main_controller * main; 462 struct jpeg_c_prep_controller * prep; 463 struct jpeg_c_coef_controller * coef; 464 struct jpeg_marker_writer * marker; 465 struct jpeg_color_converter * cconvert; 466 struct jpeg_downsampler * downsample; 467 struct jpeg_forward_dct * fdct; 468 struct jpeg_entropy_encoder * entropy; 469 jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */ 470 int script_space_size; 471 }; 472 473 474 /* Master record for a decompression instance */ 475 476 struct jpeg_decompress_struct { 477 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */ 478 479 /* Source of compressed data */ 480 struct jpeg_source_mgr * src; 481 482 /* Basic description of image --- filled in by jpeg_read_header(). */ 483 /* Application may inspect these values to decide how to process image. */ 484 485 JDIMENSION image_width; /* nominal image width (from SOF marker) */ 486 JDIMENSION image_height; /* nominal image height */ 487 int num_components; /* # of color components in JPEG image */ 488 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 489 490 /* Decompression processing parameters --- these fields must be set before 491 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes 492 * them to default values. 493 */ 494 495 J_COLOR_SPACE out_color_space; /* colorspace for output */ 496 497 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 498 499 double output_gamma; /* image gamma wanted in output */ 500 501 boolean buffered_image; /* TRUE=multiple output passes */ 502 boolean raw_data_out; /* TRUE=downsampled data wanted */ 503 504 J_DCT_METHOD dct_method; /* IDCT algorithm selector */ 505 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */ 506 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */ 507 508 boolean quantize_colors; /* TRUE=colormapped output wanted */ 509 /* the following are ignored if not quantize_colors: */ 510 J_DITHER_MODE dither_mode; /* type of color dithering to use */ 511 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */ 512 int desired_number_of_colors; /* max # colors to use in created colormap */ 513 /* these are significant only in buffered-image mode: */ 514 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */ 515 boolean enable_external_quant;/* enable future use of external colormap */ 516 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */ 517 518 /* Description of actual output image that will be returned to application. 519 * These fields are computed by jpeg_start_decompress(). 520 * You can also use jpeg_calc_output_dimensions() to determine these values 521 * in advance of calling jpeg_start_decompress(). 522 */ 523 524 JDIMENSION output_width; /* scaled image width */ 525 JDIMENSION output_height; /* scaled image height */ 526 int out_color_components; /* # of color components in out_color_space */ 527 int output_components; /* # of color components returned */ 528 /* output_components is 1 (a colormap index) when quantizing colors; 529 * otherwise it equals out_color_components. 530 */ 531 int rec_outbuf_height; /* min recommended height of scanline buffer */ 532 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows 533 * high, space and time will be wasted due to unnecessary data copying. 534 * Usually rec_outbuf_height will be 1 or 2, at most 4. 535 */ 536 537 /* When quantizing colors, the output colormap is described by these fields. 538 * The application can supply a colormap by setting colormap non-NULL before 539 * calling jpeg_start_decompress; otherwise a colormap is created during 540 * jpeg_start_decompress or jpeg_start_output. 541 * The map has out_color_components rows and actual_number_of_colors columns. 542 */ 543 int actual_number_of_colors; /* number of entries in use */ 544 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */ 545 546 /* State variables: these variables indicate the progress of decompression. 547 * The application may examine these but must not modify them. 548 */ 549 550 /* Row index of next scanline to be read from jpeg_read_scanlines(). 551 * Application may use this to control its processing loop, e.g., 552 * "while (output_scanline < output_height)". 553 */ 554 JDIMENSION output_scanline; /* 0 .. output_height-1 */ 555 556 /* Current input scan number and number of iMCU rows completed in scan. 557 * These indicate the progress of the decompressor input side. 558 */ 559 int input_scan_number; /* Number of SOS markers seen so far */ 560 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */ 561 562 /* The "output scan number" is the notional scan being displayed by the 563 * output side. The decompressor will not allow output scan/row number 564 * to get ahead of input scan/row, but it can fall arbitrarily far behind. 565 */ 566 int output_scan_number; /* Nominal scan number being displayed */ 567 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */ 568 569 /* Current progression status. coef_bits[c][i] indicates the precision 570 * with which component c's DCT coefficient i (in zigzag order) is known. 571 * It is -1 when no data has yet been received, otherwise it is the point 572 * transform (shift) value for the most recent scan of the coefficient 573 * (thus, 0 at completion of the progression). 574 * This pointer is NULL when reading a non-progressive file. 575 */ 576 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */ 577 578 /* Internal JPEG parameters --- the application usually need not look at 579 * these fields. Note that the decompressor output side may not use 580 * any parameters that can change between scans. 581 */ 582 583 /* Quantization and Huffman tables are carried forward across input 584 * datastreams when processing abbreviated JPEG datastreams. 585 */ 586 587 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 588 /* ptrs to coefficient quantization tables, or NULL if not defined */ 589 590 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 591 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 592 /* ptrs to Huffman coding tables, or NULL if not defined */ 593 594 /* These parameters are never carried across datastreams, since they 595 * are given in SOF/SOS markers or defined to be reset by SOI. 596 */ 597 598 int data_precision; /* bits of precision in image data */ 599 600 jpeg_component_info * comp_info; 601 /* comp_info[i] describes component that appears i'th in SOF */ 602 603 #if JPEG_LIB_VERSION >= 80 604 boolean is_baseline; /* TRUE if Baseline SOF0 encountered */ 605 #endif 606 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */ 607 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 608 609 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 610 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 611 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 612 613 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */ 614 615 /* These fields record data obtained from optional markers recognized by 616 * the JPEG library. 617 */ 618 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */ 619 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */ 620 UINT8 JFIF_major_version; /* JFIF version number */ 621 UINT8 JFIF_minor_version; 622 UINT8 density_unit; /* JFIF code for pixel size units */ 623 UINT16 X_density; /* Horizontal pixel density */ 624 UINT16 Y_density; /* Vertical pixel density */ 625 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */ 626 UINT8 Adobe_transform; /* Color transform code from Adobe marker */ 627 628 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 629 630 /* Aside from the specific data retained from APPn markers known to the 631 * library, the uninterpreted contents of any or all APPn and COM markers 632 * can be saved in a list for examination by the application. 633 */ 634 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */ 635 636 /* Remaining fields are known throughout decompressor, but generally 637 * should not be touched by a surrounding application. 638 */ 639 640 /* 641 * These fields are computed during decompression startup 642 */ 643 int max_h_samp_factor; /* largest h_samp_factor */ 644 int max_v_samp_factor; /* largest v_samp_factor */ 645 646 #if JPEG_LIB_VERSION >= 70 647 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */ 648 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */ 649 #else 650 int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */ 651 #endif 652 653 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ 654 /* The coefficient controller's input and output progress is measured in 655 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows 656 * in fully interleaved JPEG scans, but are used whether the scan is 657 * interleaved or not. We define an iMCU row as v_samp_factor DCT block 658 * rows of each component. Therefore, the IDCT output contains 659 * v_samp_factor*DCT_[v_]scaled_size sample rows of a component per iMCU row. 660 */ 661 662 JSAMPLE * sample_range_limit; /* table for fast range-limiting */ 663 664 /* 665 * These fields are valid during any one scan. 666 * They describe the components and MCUs actually appearing in the scan. 667 * Note that the decompressor output side must not use these fields. 668 */ 669 int comps_in_scan; /* # of JPEG components in this scan */ 670 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 671 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 672 673 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 674 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 675 676 int blocks_in_MCU; /* # of DCT blocks per MCU */ 677 int MCU_membership[D_MAX_BLOCKS_IN_MCU]; 678 /* MCU_membership[i] is index in cur_comp_info of component owning */ 679 /* i'th block in an MCU */ 680 681 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */ 682 683 #if JPEG_LIB_VERSION >= 80 684 /* These fields are derived from Se of first SOS marker. 685 */ 686 int block_size; /* the basic DCT block size: 1..16 */ 687 const int * natural_order; /* natural-order position array for entropy decode */ 688 int lim_Se; /* min( Se, DCTSIZE2-1 ) for entropy decode */ 689 #endif 690 691 /* This field is shared between entropy decoder and marker parser. 692 * It is either zero or the code of a JPEG marker that has been 693 * read from the data source, but has not yet been processed. 694 */ 695 int unread_marker; 696 697 /* 698 * Links to decompression subobjects (methods, private variables of modules) 699 */ 700 struct jpeg_decomp_master * master; 701 struct jpeg_d_main_controller * main; 702 struct jpeg_d_coef_controller * coef; 703 struct jpeg_d_post_controller * post; 704 struct jpeg_input_controller * inputctl; 705 struct jpeg_marker_reader * marker; 706 struct jpeg_entropy_decoder * entropy; 707 struct jpeg_inverse_dct * idct; 708 struct jpeg_upsampler * upsample; 709 struct jpeg_color_deconverter * cconvert; 710 struct jpeg_color_quantizer * cquantize; 711 }; 712 713 714 /* "Object" declarations for JPEG modules that may be supplied or called 715 * directly by the surrounding application. 716 * As with all objects in the JPEG library, these structs only define the 717 * publicly visible methods and state variables of a module. Additional 718 * private fields may exist after the public ones. 719 */ 720 721 722 /* Error handler object */ 723 724 struct jpeg_error_mgr { 725 /* Error exit handler: does not return to caller */ 726 JMETHOD(void, error_exit, (j_common_ptr cinfo)); 727 /* Conditionally emit a trace or warning message */ 728 JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level)); 729 /* Routine that actually outputs a trace or error message */ 730 JMETHOD(void, output_message, (j_common_ptr cinfo)); 731 /* Format a message string for the most recent JPEG error or message */ 732 JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer)); 733 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */ 734 /* Reset error state variables at start of a new image */ 735 JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo)); 736 737 /* The message ID code and any parameters are saved here. 738 * A message can have one string parameter or up to 8 int parameters. 739 */ 740 int msg_code; 741 #define JMSG_STR_PARM_MAX 80 742 union { 743 int i[8]; 744 char s[JMSG_STR_PARM_MAX]; 745 } msg_parm; 746 747 /* Standard state variables for error facility */ 748 749 int trace_level; /* max msg_level that will be displayed */ 750 751 /* For recoverable corrupt-data errors, we emit a warning message, 752 * but keep going unless emit_message chooses to abort. emit_message 753 * should count warnings in num_warnings. The surrounding application 754 * can check for bad data by seeing if num_warnings is nonzero at the 755 * end of processing. 756 */ 757 long num_warnings; /* number of corrupt-data warnings */ 758 759 /* These fields point to the table(s) of error message strings. 760 * An application can change the table pointer to switch to a different 761 * message list (typically, to change the language in which errors are 762 * reported). Some applications may wish to add additional error codes 763 * that will be handled by the JPEG library error mechanism; the second 764 * table pointer is used for this purpose. 765 * 766 * First table includes all errors generated by JPEG library itself. 767 * Error code 0 is reserved for a "no such error string" message. 768 */ 769 const char * const * jpeg_message_table; /* Library errors */ 770 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */ 771 /* Second table can be added by application (see cjpeg/djpeg for example). 772 * It contains strings numbered first_addon_message..last_addon_message. 773 */ 774 const char * const * addon_message_table; /* Non-library errors */ 775 int first_addon_message; /* code for first string in addon table */ 776 int last_addon_message; /* code for last string in addon table */ 777 }; 778 779 780 /* Progress monitor object */ 781 782 struct jpeg_progress_mgr { 783 JMETHOD(void, progress_monitor, (j_common_ptr cinfo)); 784 785 long pass_counter; /* work units completed in this pass */ 786 long pass_limit; /* total number of work units in this pass */ 787 int completed_passes; /* passes completed so far */ 788 int total_passes; /* total number of passes expected */ 789 }; 790 791 792 /* Data destination object for compression */ 793 794 struct jpeg_destination_mgr { 795 JOCTET * next_output_byte; /* => next byte to write in buffer */ 796 size_t free_in_buffer; /* # of byte spaces remaining in buffer */ 797 798 JMETHOD(void, init_destination, (j_compress_ptr cinfo)); 799 JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo)); 800 JMETHOD(void, term_destination, (j_compress_ptr cinfo)); 801 }; 802 803 804 /* Data source object for decompression */ 805 806 struct jpeg_source_mgr { 807 const JOCTET * next_input_byte; /* => next byte to read from buffer */ 808 size_t bytes_in_buffer; /* # of bytes remaining in buffer */ 809 810 JMETHOD(void, init_source, (j_decompress_ptr cinfo)); 811 JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo)); 812 JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes)); 813 JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired)); 814 JMETHOD(void, term_source, (j_decompress_ptr cinfo)); 815 }; 816 817 818 /* Memory manager object. 819 * Allocates "small" objects (a few K total), "large" objects (tens of K), 820 * and "really big" objects (virtual arrays with backing store if needed). 821 * The memory manager does not allow individual objects to be freed; rather, 822 * each created object is assigned to a pool, and whole pools can be freed 823 * at once. This is faster and more convenient than remembering exactly what 824 * to free, especially where malloc()/free() are not too speedy. 825 * NB: alloc routines never return NULL. They exit to error_exit if not 826 * successful. 827 */ 828 829 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */ 830 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */ 831 #define JPOOL_NUMPOOLS 2 832 833 typedef struct jvirt_sarray_control * jvirt_sarray_ptr; 834 typedef struct jvirt_barray_control * jvirt_barray_ptr; 835 836 837 struct jpeg_memory_mgr { 838 /* Method pointers */ 839 JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id, 840 size_t sizeofobject)); 841 JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id, 842 size_t sizeofobject)); 843 JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id, 844 JDIMENSION samplesperrow, 845 JDIMENSION numrows)); 846 JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id, 847 JDIMENSION blocksperrow, 848 JDIMENSION numrows)); 849 JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo, 850 int pool_id, 851 boolean pre_zero, 852 JDIMENSION samplesperrow, 853 JDIMENSION numrows, 854 JDIMENSION maxaccess)); 855 JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo, 856 int pool_id, 857 boolean pre_zero, 858 JDIMENSION blocksperrow, 859 JDIMENSION numrows, 860 JDIMENSION maxaccess)); 861 JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo)); 862 JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo, 863 jvirt_sarray_ptr ptr, 864 JDIMENSION start_row, 865 JDIMENSION num_rows, 866 boolean writable)); 867 JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo, 868 jvirt_barray_ptr ptr, 869 JDIMENSION start_row, 870 JDIMENSION num_rows, 871 boolean writable)); 872 JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id)); 873 JMETHOD(void, self_destruct, (j_common_ptr cinfo)); 874 875 /* Limit on memory allocation for this JPEG object. (Note that this is 876 * merely advisory, not a guaranteed maximum; it only affects the space 877 * used for virtual-array buffers.) May be changed by outer application 878 * after creating the JPEG object. 879 */ 880 long max_memory_to_use; 881 882 /* Maximum allocation request accepted by alloc_large. */ 883 long max_alloc_chunk; 884 }; 885 886 887 /* Routine signature for application-supplied marker processing methods. 888 * Need not pass marker code since it is stored in cinfo->unread_marker. 889 */ 890 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo)); 891 892 893 /* Declarations for routines called by application. 894 * The JPP macro hides prototype parameters from compilers that can't cope. 895 * Note JPP requires double parentheses. 896 */ 897 898 #ifdef HAVE_PROTOTYPES 899 #define JPP(arglist) arglist 900 #else 901 #define JPP(arglist) () 902 #endif 903 904 905 /* Short forms of external names for systems with brain-damaged linkers. 906 * We shorten external names to be unique in the first six letters, which 907 * is good enough for all known systems. 908 * (If your compiler itself needs names to be unique in less than 15 909 * characters, you are out of luck. Get a better compiler.) 910 */ 911 912 #ifdef NEED_SHORT_EXTERNAL_NAMES 913 #define jpeg_std_error jStdError 914 #define jpeg_CreateCompress jCreaCompress 915 #define jpeg_CreateDecompress jCreaDecompress 916 #define jpeg_destroy_compress jDestCompress 917 #define jpeg_destroy_decompress jDestDecompress 918 #define jpeg_stdio_dest jStdDest 919 #define jpeg_stdio_src jStdSrc 920 #if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED) 921 #define jpeg_mem_dest jMemDest 922 #define jpeg_mem_src jMemSrc 923 #endif 924 #define jpeg_set_defaults jSetDefaults 925 #define jpeg_set_colorspace jSetColorspace 926 #define jpeg_default_colorspace jDefColorspace 927 #define jpeg_set_quality jSetQuality 928 #define jpeg_set_linear_quality jSetLQuality 929 #if JPEG_LIB_VERSION >= 70 930 #define jpeg_default_qtables jDefQTables 931 #endif 932 #define jpeg_add_quant_table jAddQuantTable 933 #define jpeg_quality_scaling jQualityScaling 934 #define jpeg_simple_progression jSimProgress 935 #define jpeg_suppress_tables jSuppressTables 936 #define jpeg_alloc_quant_table jAlcQTable 937 #define jpeg_alloc_huff_table jAlcHTable 938 #define jpeg_start_compress jStrtCompress 939 #define jpeg_write_scanlines jWrtScanlines 940 #define jpeg_finish_compress jFinCompress 941 #if JPEG_LIB_VERSION >= 70 942 #define jpeg_calc_jpeg_dimensions jCjpegDimensions 943 #endif 944 #define jpeg_write_raw_data jWrtRawData 945 #define jpeg_write_marker jWrtMarker 946 #define jpeg_write_m_header jWrtMHeader 947 #define jpeg_write_m_byte jWrtMByte 948 #define jpeg_write_tables jWrtTables 949 #define jpeg_read_header jReadHeader 950 #define jpeg_start_decompress jStrtDecompress 951 #define jpeg_read_scanlines jReadScanlines 952 #define jpeg_finish_decompress jFinDecompress 953 #define jpeg_read_raw_data jReadRawData 954 #define jpeg_has_multiple_scans jHasMultScn 955 #define jpeg_start_output jStrtOutput 956 #define jpeg_finish_output jFinOutput 957 #define jpeg_input_complete jInComplete 958 #define jpeg_new_colormap jNewCMap 959 #define jpeg_consume_input jConsumeInput 960 #if JPEG_LIB_VERSION >= 80 961 #define jpeg_core_output_dimensions jCoreDimensions 962 #endif 963 #define jpeg_calc_output_dimensions jCalcDimensions 964 #define jpeg_save_markers jSaveMarkers 965 #define jpeg_set_marker_processor jSetMarker 966 #define jpeg_read_coefficients jReadCoefs 967 #define jpeg_write_coefficients jWrtCoefs 968 #define jpeg_copy_critical_parameters jCopyCrit 969 #define jpeg_abort_compress jAbrtCompress 970 #define jpeg_abort_decompress jAbrtDecompress 971 #define jpeg_abort jAbort 972 #define jpeg_destroy jDestroy 973 #define jpeg_resync_to_restart jResyncRestart 974 #endif /* NEED_SHORT_EXTERNAL_NAMES */ 975 976 977 /* Default error-management setup */ 978 EXTERN(struct jpeg_error_mgr *) jpeg_std_error 979 JPP((struct jpeg_error_mgr * err)); 980 981 /* Initialization of JPEG compression objects. 982 * jpeg_create_compress() and jpeg_create_decompress() are the exported 983 * names that applications should call. These expand to calls on 984 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information 985 * passed for version mismatch checking. 986 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx. 987 */ 988 #define jpeg_create_compress(cinfo) \ 989 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \ 990 (size_t) sizeof(struct jpeg_compress_struct)) 991 #define jpeg_create_decompress(cinfo) \ 992 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \ 993 (size_t) sizeof(struct jpeg_decompress_struct)) 994 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo, 995 int version, size_t structsize)); 996 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo, 997 int version, size_t structsize)); 998 /* Destruction of JPEG compression objects */ 999 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo)); 1000 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo)); 1001 1002 /* Standard data source and destination managers: stdio streams. */ 1003 /* Caller is responsible for opening the file before and closing after. */ 1004 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile)); 1005 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile)); 1006 1007 #if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED) 1008 /* Data source and destination managers: memory buffers. */ 1009 EXTERN(void) jpeg_mem_dest JPP((j_compress_ptr cinfo, 1010 unsigned char ** outbuffer, 1011 unsigned long * outsize)); 1012 EXTERN(void) jpeg_mem_src JPP((j_decompress_ptr cinfo, 1013 unsigned char * inbuffer, 1014 unsigned long insize)); 1015 #endif 1016 1017 /* Default parameter setup for compression */ 1018 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo)); 1019 /* Compression parameter setup aids */ 1020 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo, 1021 J_COLOR_SPACE colorspace)); 1022 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo)); 1023 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality, 1024 boolean force_baseline)); 1025 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo, 1026 int scale_factor, 1027 boolean force_baseline)); 1028 #if JPEG_LIB_VERSION >= 70 1029 EXTERN(void) jpeg_default_qtables JPP((j_compress_ptr cinfo, 1030 boolean force_baseline)); 1031 #endif 1032 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl, 1033 const unsigned int *basic_table, 1034 int scale_factor, 1035 boolean force_baseline)); 1036 EXTERN(int) jpeg_quality_scaling JPP((int quality)); 1037 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo)); 1038 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo, 1039 boolean suppress)); 1040 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo)); 1041 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo)); 1042 1043 /* Main entry points for compression */ 1044 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo, 1045 boolean write_all_tables)); 1046 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo, 1047 JSAMPARRAY scanlines, 1048 JDIMENSION num_lines)); 1049 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo)); 1050 1051 #if JPEG_LIB_VERSION >= 70 1052 /* Precalculate JPEG dimensions for current compression parameters. */ 1053 EXTERN(void) jpeg_calc_jpeg_dimensions JPP((j_compress_ptr cinfo)); 1054 #endif 1055 1056 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */ 1057 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo, 1058 JSAMPIMAGE data, 1059 JDIMENSION num_lines)); 1060 1061 /* Write a special marker. See libjpeg.txt concerning safe usage. */ 1062 EXTERN(void) jpeg_write_marker 1063 JPP((j_compress_ptr cinfo, int marker, 1064 const JOCTET * dataptr, unsigned int datalen)); 1065 /* Same, but piecemeal. */ 1066 EXTERN(void) jpeg_write_m_header 1067 JPP((j_compress_ptr cinfo, int marker, unsigned int datalen)); 1068 EXTERN(void) jpeg_write_m_byte 1069 JPP((j_compress_ptr cinfo, int val)); 1070 1071 /* Alternate compression function: just write an abbreviated table file */ 1072 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo)); 1073 1074 /* Decompression startup: read start of JPEG datastream to see what's there */ 1075 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo, 1076 boolean require_image)); 1077 /* Return value is one of: */ 1078 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */ 1079 #define JPEG_HEADER_OK 1 /* Found valid image datastream */ 1080 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */ 1081 /* If you pass require_image = TRUE (normal case), you need not check for 1082 * a TABLES_ONLY return code; an abbreviated file will cause an error exit. 1083 * JPEG_SUSPENDED is only possible if you use a data source module that can 1084 * give a suspension return (the stdio source module doesn't). 1085 */ 1086 1087 /* Main entry points for decompression */ 1088 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo)); 1089 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo, 1090 JSAMPARRAY scanlines, 1091 JDIMENSION max_lines)); 1092 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo)); 1093 1094 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */ 1095 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo, 1096 JSAMPIMAGE data, 1097 JDIMENSION max_lines)); 1098 1099 /* Additional entry points for buffered-image mode. */ 1100 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo)); 1101 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo, 1102 int scan_number)); 1103 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo)); 1104 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo)); 1105 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo)); 1106 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo)); 1107 /* Return value is one of: */ 1108 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */ 1109 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */ 1110 #define JPEG_REACHED_EOI 2 /* Reached end of image */ 1111 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */ 1112 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */ 1113 1114 /* Precalculate output dimensions for current decompression parameters. */ 1115 #if JPEG_LIB_VERSION >= 80 1116 EXTERN(void) jpeg_core_output_dimensions JPP((j_decompress_ptr cinfo)); 1117 #endif 1118 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo)); 1119 1120 /* Control saving of COM and APPn markers into marker_list. */ 1121 EXTERN(void) jpeg_save_markers 1122 JPP((j_decompress_ptr cinfo, int marker_code, 1123 unsigned int length_limit)); 1124 1125 /* Install a special processing method for COM or APPn markers. */ 1126 EXTERN(void) jpeg_set_marker_processor 1127 JPP((j_decompress_ptr cinfo, int marker_code, 1128 jpeg_marker_parser_method routine)); 1129 1130 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */ 1131 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo)); 1132 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo, 1133 jvirt_barray_ptr * coef_arrays)); 1134 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo, 1135 j_compress_ptr dstinfo)); 1136 1137 /* If you choose to abort compression or decompression before completing 1138 * jpeg_finish_(de)compress, then you need to clean up to release memory, 1139 * temporary files, etc. You can just call jpeg_destroy_(de)compress 1140 * if you're done with the JPEG object, but if you want to clean it up and 1141 * reuse it, call this: 1142 */ 1143 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo)); 1144 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo)); 1145 1146 /* Generic versions of jpeg_abort and jpeg_destroy that work on either 1147 * flavor of JPEG object. These may be more convenient in some places. 1148 */ 1149 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo)); 1150 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo)); 1151 1152 /* Default restart-marker-resync procedure for use by data source modules */ 1153 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo, 1154 int desired)); 1155 1156 1157 /* These marker codes are exported since applications and data source modules 1158 * are likely to want to use them. 1159 */ 1160 1161 #define JPEG_RST0 0xD0 /* RST0 marker code */ 1162 #define JPEG_EOI 0xD9 /* EOI marker code */ 1163 #define JPEG_APP0 0xE0 /* APP0 marker code */ 1164 #define JPEG_COM 0xFE /* COM marker code */ 1165 1166 1167 /* If we have a brain-damaged compiler that emits warnings (or worse, errors) 1168 * for structure definitions that are never filled in, keep it quiet by 1169 * supplying dummy definitions for the various substructures. 1170 */ 1171 1172 #ifdef INCOMPLETE_TYPES_BROKEN 1173 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */ 1174 struct jvirt_sarray_control { long dummy; }; 1175 struct jvirt_barray_control { long dummy; }; 1176 struct jpeg_comp_master { long dummy; }; 1177 struct jpeg_c_main_controller { long dummy; }; 1178 struct jpeg_c_prep_controller { long dummy; }; 1179 struct jpeg_c_coef_controller { long dummy; }; 1180 struct jpeg_marker_writer { long dummy; }; 1181 struct jpeg_color_converter { long dummy; }; 1182 struct jpeg_downsampler { long dummy; }; 1183 struct jpeg_forward_dct { long dummy; }; 1184 struct jpeg_entropy_encoder { long dummy; }; 1185 struct jpeg_decomp_master { long dummy; }; 1186 struct jpeg_d_main_controller { long dummy; }; 1187 struct jpeg_d_coef_controller { long dummy; }; 1188 struct jpeg_d_post_controller { long dummy; }; 1189 struct jpeg_input_controller { long dummy; }; 1190 struct jpeg_marker_reader { long dummy; }; 1191 struct jpeg_entropy_decoder { long dummy; }; 1192 struct jpeg_inverse_dct { long dummy; }; 1193 struct jpeg_upsampler { long dummy; }; 1194 struct jpeg_color_deconverter { long dummy; }; 1195 struct jpeg_color_quantizer { long dummy; }; 1196 #endif /* JPEG_INTERNALS */ 1197 #endif /* INCOMPLETE_TYPES_BROKEN */ 1198 1199 1200 /* 1201 * The JPEG library modules define JPEG_INTERNALS before including this file. 1202 * The internal structure declarations are read only when that is true. 1203 * Applications using the library should not include jpegint.h, but may wish 1204 * to include jerror.h. 1205 */ 1206 1207 #ifdef JPEG_INTERNALS 1208 #include "jpegint.h" /* fetch private declarations */ 1209 #include "jerror.h" /* fetch error codes too */ 1210 #endif 1211 1212 #ifdef __cplusplus 1213 #ifndef DONT_USE_EXTERN_C 1214 } 1215 #endif 1216 #endif 1217 1218 #endif /* JPEGLIB_H */ 1219
