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File indexing completed on 2025-09-17 09:20:50
0001 /* 0002 * jpeglib.h 0003 * 0004 * This file was part of the Independent JPEG Group's software: 0005 * Copyright (C) 1991-1998, Thomas G. Lane. 0006 * Modified 2002-2009 by Guido Vollbeding. 0007 * Lossless JPEG Modifications: 0008 * Copyright (C) 1999, Ken Murchison. 0009 * libjpeg-turbo Modifications: 0010 * Copyright (C) 2009-2011, 2013-2014, 2016-2017, 2020, 2022-2024, 0011 D. R. Commander. 0012 * Copyright (C) 2015, Google, Inc. 0013 * For conditions of distribution and use, see the accompanying README.ijg 0014 * file. 0015 * 0016 * This file defines the application interface for the JPEG library. 0017 * Most applications using the library need only include this file, 0018 * and perhaps jerror.h if they want to know the exact error codes. 0019 */ 0020 0021 /* NOTE: This header file does not include stdio.h, despite the fact that it 0022 * uses FILE and size_t. That is by design, since the libjpeg API predates the 0023 * widespread adoption of ANSI/ISO C. Referring to libjpeg.txt, it is a 0024 * documented requirement that calling programs "include system headers that 0025 * define at least the typedefs FILE and size_t" before including jpeglib.h. 0026 * Technically speaking, changing that requirement by including stdio.h here 0027 * would break backward API compatibility. Please do not file bug reports, 0028 * feature requests, or pull requests regarding this. 0029 */ 0030 0031 #ifndef JPEGLIB_H 0032 #define JPEGLIB_H 0033 0034 /* 0035 * First we include the configuration files that record how this 0036 * installation of the JPEG library is set up. jconfig.h can be 0037 * generated automatically for many systems. jmorecfg.h contains 0038 * manual configuration options that most people need not worry about. 0039 */ 0040 0041 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */ 0042 #include "jconfig.h" /* widely used configuration options */ 0043 #endif 0044 #include "jmorecfg.h" /* seldom changed options */ 0045 0046 0047 #ifdef __cplusplus 0048 #ifndef DONT_USE_EXTERN_C 0049 extern "C" { 0050 #endif 0051 #endif 0052 0053 0054 /* Various constants determining the sizes of things. 0055 * All of these are specified by the JPEG standard, so don't change them 0056 * if you want to be compatible. 0057 */ 0058 0059 /* NOTE: In lossless mode, an MCU contains one or more samples rather than one 0060 * or more 8x8 DCT blocks, so the term "data unit" is used to generically 0061 * describe a sample in lossless mode or an 8x8 DCT block in lossy mode. To 0062 * preserve backward API/ABI compatibility, the field and macro names retain 0063 * the "block" terminology. 0064 */ 0065 0066 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */ 0067 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */ 0068 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */ 0069 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */ 0070 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */ 0071 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */ 0072 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */ 0073 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard; 0074 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU. 0075 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU 0076 * to handle it. We even let you do this from the jconfig.h file. However, 0077 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe 0078 * sometimes emits noncompliant files doesn't mean you should too. 0079 */ 0080 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on data units/MCU */ 0081 #ifndef D_MAX_BLOCKS_IN_MCU 0082 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on data units/MCU */ 0083 #endif 0084 0085 0086 /* Data structures for images (arrays of samples and of DCT coefficients). 0087 */ 0088 0089 typedef JSAMPLE *JSAMPROW; /* ptr to one image row of pixel samples. */ 0090 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ 0091 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ 0092 0093 typedef J12SAMPLE *J12SAMPROW; /* ptr to one image row of 12-bit pixel 0094 samples. */ 0095 typedef J12SAMPROW *J12SAMPARRAY; /* ptr to some 12-bit sample rows (a 2-D 0096 12-bit sample array) */ 0097 typedef J12SAMPARRAY *J12SAMPIMAGE; /* a 3-D 12-bit sample array: top index is 0098 color */ 0099 0100 typedef J16SAMPLE *J16SAMPROW; /* ptr to one image row of 16-bit pixel 0101 samples. */ 0102 typedef J16SAMPROW *J16SAMPARRAY; /* ptr to some 16-bit sample rows (a 2-D 0103 16-bit sample array) */ 0104 typedef J16SAMPARRAY *J16SAMPIMAGE; /* a 3-D 16-bit sample array: top index is 0105 color */ 0106 0107 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ 0108 typedef JBLOCK *JBLOCKROW; /* pointer to one row of coefficient blocks */ 0109 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ 0110 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ 0111 0112 typedef JCOEF *JCOEFPTR; /* useful in a couple of places */ 0113 0114 0115 /* Types for JPEG compression parameters and working tables. */ 0116 0117 0118 /* DCT coefficient quantization tables. */ 0119 0120 typedef struct { 0121 /* This array gives the coefficient quantizers in natural array order 0122 * (not the zigzag order in which they are stored in a JPEG DQT marker). 0123 * CAUTION: IJG versions prior to v6a kept this array in zigzag order. 0124 */ 0125 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */ 0126 /* This field is used only during compression. It's initialized FALSE when 0127 * the table is created, and set TRUE when it's been output to the file. 0128 * You could suppress output of a table by setting this to TRUE. 0129 * (See jpeg_suppress_tables for an example.) 0130 */ 0131 boolean sent_table; /* TRUE when table has been output */ 0132 } JQUANT_TBL; 0133 0134 0135 /* Huffman coding tables. */ 0136 0137 typedef struct { 0138 /* These two fields directly represent the contents of a JPEG DHT marker */ 0139 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ 0140 /* length k bits; bits[0] is unused */ 0141 UINT8 huffval[256]; /* The symbols, in order of incr code length */ 0142 /* This field is used only during compression. It's initialized FALSE when 0143 * the table is created, and set TRUE when it's been output to the file. 0144 * You could suppress output of a table by setting this to TRUE. 0145 * (See jpeg_suppress_tables for an example.) 0146 */ 0147 boolean sent_table; /* TRUE when table has been output */ 0148 } JHUFF_TBL; 0149 0150 0151 /* Basic info about one component (color channel). */ 0152 0153 typedef struct { 0154 /* These values are fixed over the whole image. */ 0155 /* For compression, they must be supplied by parameter setup; */ 0156 /* for decompression, they are read from the SOF marker. */ 0157 int component_id; /* identifier for this component (0..255) */ 0158 int component_index; /* its index in SOF or cinfo->comp_info[] */ 0159 int h_samp_factor; /* horizontal sampling factor (1..4) */ 0160 int v_samp_factor; /* vertical sampling factor (1..4) */ 0161 int quant_tbl_no; /* quantization table selector (0..3) */ 0162 /* These values may vary between scans. */ 0163 /* For compression, they must be supplied by parameter setup; */ 0164 /* for decompression, they are read from the SOS marker. */ 0165 /* The decompressor output side may not use these variables. */ 0166 int dc_tbl_no; /* DC entropy table selector (0..3) */ 0167 int ac_tbl_no; /* AC entropy table selector (0..3) */ 0168 0169 /* Remaining fields should be treated as private by applications. */ 0170 0171 /* These values are computed during compression or decompression startup: */ 0172 /* Component's size in data units. 0173 * In lossy mode, any dummy blocks added to complete an MCU are not counted; 0174 * therefore these values do not depend on whether a scan is interleaved or 0175 * not. In lossless mode, these are always equal to the image width and 0176 * height. 0177 */ 0178 JDIMENSION width_in_blocks; 0179 JDIMENSION height_in_blocks; 0180 /* Size of a data unit in samples. Always DCTSIZE for lossy compression. 0181 * For lossy decompression this is the size of the output from one DCT block, 0182 * reflecting any scaling we choose to apply during the IDCT step. 0183 * Values from 1 to 16 are supported. Note that different components may 0184 * receive different IDCT scalings. In lossless mode, this is always equal 0185 * to 1. 0186 */ 0187 #if JPEG_LIB_VERSION >= 70 0188 int DCT_h_scaled_size; 0189 int DCT_v_scaled_size; 0190 #else 0191 int DCT_scaled_size; 0192 #endif 0193 /* The downsampled dimensions are the component's actual, unpadded number 0194 * of samples at the main buffer (preprocessing/compression interface), thus 0195 * downsampled_width = ceil(image_width * Hi/Hmax) 0196 * and similarly for height. For lossy decompression, IDCT scaling is 0197 * included, so 0198 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_[h_]scaled_size/DCTSIZE) 0199 * In lossless mode, these are always equal to the image width and height. 0200 */ 0201 JDIMENSION downsampled_width; /* actual width in samples */ 0202 JDIMENSION downsampled_height; /* actual height in samples */ 0203 /* This flag is used only for decompression. In cases where some of the 0204 * components will be ignored (eg grayscale output from YCbCr image), 0205 * we can skip most computations for the unused components. 0206 */ 0207 boolean component_needed; /* do we need the value of this component? */ 0208 0209 /* These values are computed before starting a scan of the component. */ 0210 /* The decompressor output side may not use these variables. */ 0211 int MCU_width; /* number of data units per MCU, horizontally */ 0212 int MCU_height; /* number of data units per MCU, vertically */ 0213 int MCU_blocks; /* MCU_width * MCU_height */ 0214 int MCU_sample_width; /* MCU width in samples, MCU_width*DCT_[h_]scaled_size */ 0215 int last_col_width; /* # of non-dummy data units across in last MCU */ 0216 int last_row_height; /* # of non-dummy data units down in last MCU */ 0217 0218 /* Saved quantization table for component; NULL if none yet saved. 0219 * See jdinput.c comments about the need for this information. 0220 * This field is currently used only for decompression. 0221 */ 0222 JQUANT_TBL *quant_table; 0223 0224 /* Private per-component storage for DCT or IDCT subsystem. */ 0225 void *dct_table; 0226 } jpeg_component_info; 0227 0228 0229 /* The script for encoding a multiple-scan file is an array of these: */ 0230 0231 typedef struct { 0232 int comps_in_scan; /* number of components encoded in this scan */ 0233 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */ 0234 int Ss, Se; /* progressive JPEG spectral selection parms 0235 (Ss is the predictor selection value in 0236 lossless mode) */ 0237 int Ah, Al; /* progressive JPEG successive approx. parms 0238 (Al is the point transform value in lossless 0239 mode) */ 0240 } jpeg_scan_info; 0241 0242 /* The decompressor can save APPn and COM markers in a list of these: */ 0243 0244 typedef struct jpeg_marker_struct *jpeg_saved_marker_ptr; 0245 0246 struct jpeg_marker_struct { 0247 jpeg_saved_marker_ptr next; /* next in list, or NULL */ 0248 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */ 0249 unsigned int original_length; /* # bytes of data in the file */ 0250 unsigned int data_length; /* # bytes of data saved at data[] */ 0251 JOCTET *data; /* the data contained in the marker */ 0252 /* the marker length word is not counted in data_length or original_length */ 0253 }; 0254 0255 /* Known color spaces. */ 0256 0257 #define JCS_EXTENSIONS 1 0258 #define JCS_ALPHA_EXTENSIONS 1 0259 0260 typedef enum { 0261 JCS_UNKNOWN, /* error/unspecified */ 0262 JCS_GRAYSCALE, /* monochrome */ 0263 JCS_RGB, /* red/green/blue as specified by the RGB_RED, 0264 RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros */ 0265 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ 0266 JCS_CMYK, /* C/M/Y/K */ 0267 JCS_YCCK, /* Y/Cb/Cr/K */ 0268 JCS_EXT_RGB, /* red/green/blue */ 0269 JCS_EXT_RGBX, /* red/green/blue/x */ 0270 JCS_EXT_BGR, /* blue/green/red */ 0271 JCS_EXT_BGRX, /* blue/green/red/x */ 0272 JCS_EXT_XBGR, /* x/blue/green/red */ 0273 JCS_EXT_XRGB, /* x/red/green/blue */ 0274 /* When out_color_space it set to JCS_EXT_RGBX, JCS_EXT_BGRX, JCS_EXT_XBGR, 0275 or JCS_EXT_XRGB during decompression, the X byte is undefined, and in 0276 order to ensure the best performance, libjpeg-turbo can set that byte to 0277 whatever value it wishes. Use the following colorspace constants to 0278 ensure that the X byte is set to 0xFF, so that it can be interpreted as an 0279 opaque alpha channel. */ 0280 JCS_EXT_RGBA, /* red/green/blue/alpha */ 0281 JCS_EXT_BGRA, /* blue/green/red/alpha */ 0282 JCS_EXT_ABGR, /* alpha/blue/green/red */ 0283 JCS_EXT_ARGB, /* alpha/red/green/blue */ 0284 JCS_RGB565 /* 5-bit red/6-bit green/5-bit blue 0285 [decompression only] */ 0286 } J_COLOR_SPACE; 0287 0288 /* DCT/IDCT algorithm options. */ 0289 0290 typedef enum { 0291 JDCT_ISLOW, /* accurate integer method */ 0292 JDCT_IFAST, /* less accurate integer method [legacy feature] */ 0293 JDCT_FLOAT /* floating-point method [legacy feature] */ 0294 } J_DCT_METHOD; 0295 0296 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */ 0297 #define JDCT_DEFAULT JDCT_ISLOW 0298 #endif 0299 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */ 0300 #define JDCT_FASTEST JDCT_IFAST 0301 #endif 0302 0303 /* Dithering options for decompression. */ 0304 0305 typedef enum { 0306 JDITHER_NONE, /* no dithering */ 0307 JDITHER_ORDERED, /* simple ordered dither */ 0308 JDITHER_FS /* Floyd-Steinberg error diffusion dither */ 0309 } J_DITHER_MODE; 0310 0311 0312 /* Common fields between JPEG compression and decompression master structs. */ 0313 0314 #define jpeg_common_fields \ 0315 struct jpeg_error_mgr *err; /* Error handler module */ \ 0316 struct jpeg_memory_mgr *mem; /* Memory manager module */ \ 0317 struct jpeg_progress_mgr *progress; /* Progress monitor, or NULL if none */ \ 0318 void *client_data; /* Available for use by application */ \ 0319 boolean is_decompressor; /* So common code can tell which is which */ \ 0320 int global_state /* For checking call sequence validity */ 0321 0322 /* Routines that are to be used by both halves of the library are declared 0323 * to receive a pointer to this structure. There are no actual instances of 0324 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct. 0325 */ 0326 struct jpeg_common_struct { 0327 jpeg_common_fields; /* Fields common to both master struct types */ 0328 /* Additional fields follow in an actual jpeg_compress_struct or 0329 * jpeg_decompress_struct. All three structs must agree on these 0330 * initial fields! (This would be a lot cleaner in C++.) 0331 */ 0332 }; 0333 0334 typedef struct jpeg_common_struct *j_common_ptr; 0335 typedef struct jpeg_compress_struct *j_compress_ptr; 0336 typedef struct jpeg_decompress_struct *j_decompress_ptr; 0337 0338 0339 /* Master record for a compression instance */ 0340 0341 struct jpeg_compress_struct { 0342 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */ 0343 0344 /* Destination for compressed data */ 0345 struct jpeg_destination_mgr *dest; 0346 0347 /* Description of source image --- these fields must be filled in by 0348 * outer application before starting compression. in_color_space must 0349 * be correct before you can even call jpeg_set_defaults(). 0350 */ 0351 0352 JDIMENSION image_width; /* input image width */ 0353 JDIMENSION image_height; /* input image height */ 0354 int input_components; /* # of color components in input image */ 0355 J_COLOR_SPACE in_color_space; /* colorspace of input image */ 0356 0357 double input_gamma; /* image gamma of input image */ 0358 0359 /* Compression parameters --- these fields must be set before calling 0360 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to 0361 * initialize everything to reasonable defaults, then changing anything 0362 * the application specifically wants to change. That way you won't get 0363 * burnt when new parameters are added. Also note that there are several 0364 * helper routines to simplify changing parameters. 0365 */ 0366 0367 #if JPEG_LIB_VERSION >= 70 0368 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 0369 0370 JDIMENSION jpeg_width; /* scaled JPEG image width */ 0371 JDIMENSION jpeg_height; /* scaled JPEG image height */ 0372 /* Dimensions of actual JPEG image that will be written to file, 0373 * derived from input dimensions by scaling factors above. 0374 * These fields are computed by jpeg_start_compress(). 0375 * You can also use jpeg_calc_jpeg_dimensions() to determine these values 0376 * in advance of calling jpeg_start_compress(). 0377 */ 0378 #endif 0379 0380 int data_precision; /* bits of precision in image data */ 0381 0382 int num_components; /* # of color components in JPEG image */ 0383 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 0384 0385 jpeg_component_info *comp_info; 0386 /* comp_info[i] describes component that appears i'th in SOF */ 0387 0388 JQUANT_TBL *quant_tbl_ptrs[NUM_QUANT_TBLS]; 0389 #if JPEG_LIB_VERSION >= 70 0390 int q_scale_factor[NUM_QUANT_TBLS]; 0391 #endif 0392 /* ptrs to coefficient quantization tables, or NULL if not defined, 0393 * and corresponding scale factors (percentage, initialized 100). 0394 */ 0395 0396 JHUFF_TBL *dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 0397 JHUFF_TBL *ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 0398 /* ptrs to Huffman coding tables, or NULL if not defined */ 0399 0400 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 0401 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 0402 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 0403 0404 int num_scans; /* # of entries in scan_info array */ 0405 const jpeg_scan_info *scan_info; /* script for multi-scan file, or NULL */ 0406 /* The default value of scan_info is NULL, which causes a single-scan 0407 * sequential JPEG file to be emitted. To create a multi-scan file, 0408 * set num_scans and scan_info to point to an array of scan definitions. 0409 */ 0410 0411 boolean raw_data_in; /* TRUE=caller supplies downsampled data */ 0412 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 0413 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ 0414 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 0415 #if JPEG_LIB_VERSION >= 70 0416 boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */ 0417 #endif 0418 int smoothing_factor; /* 1..100, or 0 for no input smoothing */ 0419 J_DCT_METHOD dct_method; /* DCT algorithm selector */ 0420 0421 /* The restart interval can be specified in absolute MCUs by setting 0422 * restart_interval, or in MCU rows by setting restart_in_rows 0423 * (in which case the correct restart_interval will be figured 0424 * for each scan). 0425 */ 0426 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */ 0427 int restart_in_rows; /* if > 0, MCU rows per restart interval */ 0428 0429 /* Parameters controlling emission of special markers. */ 0430 0431 boolean write_JFIF_header; /* should a JFIF marker be written? */ 0432 UINT8 JFIF_major_version; /* What to write for the JFIF version number */ 0433 UINT8 JFIF_minor_version; 0434 /* These three values are not used by the JPEG code, merely copied */ 0435 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ 0436 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ 0437 /* ratio is defined by X_density/Y_density even when density_unit=0. */ 0438 UINT8 density_unit; /* JFIF code for pixel size units */ 0439 UINT16 X_density; /* Horizontal pixel density */ 0440 UINT16 Y_density; /* Vertical pixel density */ 0441 boolean write_Adobe_marker; /* should an Adobe marker be written? */ 0442 0443 /* State variable: index of next scanline to be written to 0444 * jpeg_write_scanlines(). Application may use this to control its 0445 * processing loop, e.g., "while (next_scanline < image_height)". 0446 */ 0447 0448 JDIMENSION next_scanline; /* 0 .. image_height-1 */ 0449 0450 /* Remaining fields are known throughout compressor, but generally 0451 * should not be touched by a surrounding application. 0452 */ 0453 0454 /* 0455 * These fields are computed during compression startup 0456 */ 0457 boolean progressive_mode; /* TRUE if scan script uses progressive mode */ 0458 int max_h_samp_factor; /* largest h_samp_factor */ 0459 int max_v_samp_factor; /* largest v_samp_factor */ 0460 0461 #if JPEG_LIB_VERSION >= 70 0462 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */ 0463 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */ 0464 #endif 0465 0466 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coefficient or 0467 difference controller */ 0468 /* The coefficient or difference controller receives data in units of MCU 0469 * rows as defined for fully interleaved scans (whether the JPEG file is 0470 * interleaved or not). In lossy mode, there are v_samp_factor * DCTSIZE 0471 * sample rows of each component in an "iMCU" (interleaved MCU) row. In 0472 * lossless mode, total_iMCU_rows is always equal to the image height. 0473 */ 0474 0475 /* 0476 * These fields are valid during any one scan. 0477 * They describe the components and MCUs actually appearing in the scan. 0478 */ 0479 int comps_in_scan; /* # of JPEG components in this scan */ 0480 jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN]; 0481 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 0482 0483 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 0484 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 0485 0486 int blocks_in_MCU; /* # of data units per MCU */ 0487 int MCU_membership[C_MAX_BLOCKS_IN_MCU]; 0488 /* MCU_membership[i] is index in cur_comp_info of component owning */ 0489 /* i'th data unit in an MCU */ 0490 0491 int Ss, Se, Ah, Al; /* progressive/lossless JPEG parameters for 0492 scan */ 0493 0494 #if JPEG_LIB_VERSION >= 80 0495 int block_size; /* the basic DCT block size: 1..16 */ 0496 const int *natural_order; /* natural-order position array */ 0497 int lim_Se; /* min( Se, DCTSIZE2-1 ) */ 0498 #endif 0499 0500 /* 0501 * Links to compression subobjects (methods and private variables of modules) 0502 */ 0503 struct jpeg_comp_master *master; 0504 struct jpeg_c_main_controller *main; 0505 struct jpeg_c_prep_controller *prep; 0506 struct jpeg_c_coef_controller *coef; 0507 struct jpeg_marker_writer *marker; 0508 struct jpeg_color_converter *cconvert; 0509 struct jpeg_downsampler *downsample; 0510 struct jpeg_forward_dct *fdct; 0511 struct jpeg_entropy_encoder *entropy; 0512 jpeg_scan_info *script_space; /* workspace for jpeg_simple_progression */ 0513 int script_space_size; 0514 }; 0515 0516 0517 /* Master record for a decompression instance */ 0518 0519 struct jpeg_decompress_struct { 0520 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */ 0521 0522 /* Source of compressed data */ 0523 struct jpeg_source_mgr *src; 0524 0525 /* Basic description of image --- filled in by jpeg_read_header(). */ 0526 /* Application may inspect these values to decide how to process image. */ 0527 0528 JDIMENSION image_width; /* nominal image width (from SOF marker) */ 0529 JDIMENSION image_height; /* nominal image height */ 0530 int num_components; /* # of color components in JPEG image */ 0531 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 0532 0533 /* Decompression processing parameters --- these fields must be set before 0534 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes 0535 * them to default values. 0536 */ 0537 0538 J_COLOR_SPACE out_color_space; /* colorspace for output */ 0539 0540 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 0541 0542 double output_gamma; /* image gamma wanted in output */ 0543 0544 boolean buffered_image; /* TRUE=multiple output passes */ 0545 boolean raw_data_out; /* TRUE=downsampled data wanted */ 0546 0547 J_DCT_METHOD dct_method; /* IDCT algorithm selector */ 0548 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */ 0549 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */ 0550 0551 boolean quantize_colors; /* TRUE=colormapped output wanted */ 0552 /* the following are ignored if not quantize_colors: */ 0553 J_DITHER_MODE dither_mode; /* type of color dithering to use */ 0554 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */ 0555 int desired_number_of_colors; /* max # colors to use in created colormap */ 0556 /* these are significant only in buffered-image mode: */ 0557 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */ 0558 boolean enable_external_quant;/* enable future use of external colormap */ 0559 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */ 0560 0561 /* Description of actual output image that will be returned to application. 0562 * These fields are computed by jpeg_start_decompress(). 0563 * You can also use jpeg_calc_output_dimensions() to determine these values 0564 * in advance of calling jpeg_start_decompress(). 0565 */ 0566 0567 JDIMENSION output_width; /* scaled image width */ 0568 JDIMENSION output_height; /* scaled image height */ 0569 int out_color_components; /* # of color components in out_color_space */ 0570 int output_components; /* # of color components returned */ 0571 /* output_components is 1 (a colormap index) when quantizing colors; 0572 * otherwise it equals out_color_components. 0573 */ 0574 int rec_outbuf_height; /* min recommended height of scanline buffer */ 0575 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows 0576 * high, space and time will be wasted due to unnecessary data copying. 0577 * Usually rec_outbuf_height will be 1 or 2, at most 4. 0578 */ 0579 0580 /* When quantizing colors, the output colormap is described by these fields. 0581 * The application can supply a colormap by setting colormap non-NULL before 0582 * calling jpeg_start_decompress; otherwise a colormap is created during 0583 * jpeg_start_decompress or jpeg_start_output. 0584 * The map has out_color_components rows and actual_number_of_colors columns. 0585 */ 0586 int actual_number_of_colors; /* number of entries in use */ 0587 JSAMPARRAY colormap; /* The color map as a 2-D pixel array 0588 If data_precision is 12, then this is 0589 actually a J12SAMPARRAY, so callers must 0590 type-cast it in order to read/write 12-bit 0591 samples from/to the array. */ 0592 0593 /* State variables: these variables indicate the progress of decompression. 0594 * The application may examine these but must not modify them. 0595 */ 0596 0597 /* Row index of next scanline to be read from jpeg_read_scanlines(). 0598 * Application may use this to control its processing loop, e.g., 0599 * "while (output_scanline < output_height)". 0600 */ 0601 JDIMENSION output_scanline; /* 0 .. output_height-1 */ 0602 0603 /* Current input scan number and number of iMCU rows completed in scan. 0604 * These indicate the progress of the decompressor input side. 0605 */ 0606 int input_scan_number; /* Number of SOS markers seen so far */ 0607 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */ 0608 0609 /* The "output scan number" is the notional scan being displayed by the 0610 * output side. The decompressor will not allow output scan/row number 0611 * to get ahead of input scan/row, but it can fall arbitrarily far behind. 0612 */ 0613 int output_scan_number; /* Nominal scan number being displayed */ 0614 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */ 0615 0616 /* Current progression status. coef_bits[c][i] indicates the precision 0617 * with which component c's DCT coefficient i (in zigzag order) is known. 0618 * It is -1 when no data has yet been received, otherwise it is the point 0619 * transform (shift) value for the most recent scan of the coefficient 0620 * (thus, 0 at completion of the progression). 0621 * This pointer is NULL when reading a non-progressive file. 0622 */ 0623 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */ 0624 0625 /* Internal JPEG parameters --- the application usually need not look at 0626 * these fields. Note that the decompressor output side may not use 0627 * any parameters that can change between scans. 0628 */ 0629 0630 /* Quantization and Huffman tables are carried forward across input 0631 * datastreams when processing abbreviated JPEG datastreams. 0632 */ 0633 0634 JQUANT_TBL *quant_tbl_ptrs[NUM_QUANT_TBLS]; 0635 /* ptrs to coefficient quantization tables, or NULL if not defined */ 0636 0637 JHUFF_TBL *dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 0638 JHUFF_TBL *ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 0639 /* ptrs to Huffman coding tables, or NULL if not defined */ 0640 0641 /* These parameters are never carried across datastreams, since they 0642 * are given in SOF/SOS markers or defined to be reset by SOI. 0643 */ 0644 0645 int data_precision; /* bits of precision in image data */ 0646 0647 jpeg_component_info *comp_info; 0648 /* comp_info[i] describes component that appears i'th in SOF */ 0649 0650 #if JPEG_LIB_VERSION >= 80 0651 boolean is_baseline; /* TRUE if Baseline SOF0 encountered */ 0652 #endif 0653 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */ 0654 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 0655 0656 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 0657 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 0658 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 0659 0660 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */ 0661 0662 /* These fields record data obtained from optional markers recognized by 0663 * the JPEG library. 0664 */ 0665 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */ 0666 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */ 0667 UINT8 JFIF_major_version; /* JFIF version number */ 0668 UINT8 JFIF_minor_version; 0669 UINT8 density_unit; /* JFIF code for pixel size units */ 0670 UINT16 X_density; /* Horizontal pixel density */ 0671 UINT16 Y_density; /* Vertical pixel density */ 0672 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */ 0673 UINT8 Adobe_transform; /* Color transform code from Adobe marker */ 0674 0675 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 0676 0677 /* Aside from the specific data retained from APPn markers known to the 0678 * library, the uninterpreted contents of any or all APPn and COM markers 0679 * can be saved in a list for examination by the application. 0680 */ 0681 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */ 0682 0683 /* Remaining fields are known throughout decompressor, but generally 0684 * should not be touched by a surrounding application. 0685 */ 0686 0687 /* 0688 * These fields are computed during decompression startup 0689 */ 0690 int max_h_samp_factor; /* largest h_samp_factor */ 0691 int max_v_samp_factor; /* largest v_samp_factor */ 0692 0693 #if JPEG_LIB_VERSION >= 70 0694 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */ 0695 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */ 0696 #else 0697 int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */ 0698 #endif 0699 0700 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ 0701 /* The coefficient or difference controller's input and output progress is 0702 * measured in units of "iMCU" (interleaved MCU) rows. These are the same as 0703 * MCU rows in fully interleaved JPEG scans, but are used whether the scan is 0704 * interleaved or not. In lossy mode, we define an iMCU row as v_samp_factor 0705 * DCT block rows of each component. Therefore, the IDCT output contains 0706 * v_samp_factor*DCT_[v_]scaled_size sample rows of a component per iMCU row. 0707 * In lossless mode, total_iMCU_rows is always equal to the image height. 0708 */ 0709 0710 JSAMPLE *sample_range_limit; /* table for fast range-limiting 0711 If data_precision is 12 or 16, then this is 0712 actually a J12SAMPLE pointer or a J16SAMPLE 0713 pointer, so callers must type-cast it in 0714 order to read 12-bit or 16-bit samples from 0715 the array. */ 0716 0717 /* 0718 * These fields are valid during any one scan. 0719 * They describe the components and MCUs actually appearing in the scan. 0720 * Note that the decompressor output side must not use these fields. 0721 */ 0722 int comps_in_scan; /* # of JPEG components in this scan */ 0723 jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN]; 0724 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 0725 0726 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 0727 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 0728 0729 int blocks_in_MCU; /* # of data units per MCU */ 0730 int MCU_membership[D_MAX_BLOCKS_IN_MCU]; 0731 /* MCU_membership[i] is index in cur_comp_info of component owning */ 0732 /* i'th data unit in an MCU */ 0733 0734 int Ss, Se, Ah, Al; /* progressive/lossless JPEG parameters for 0735 scan */ 0736 0737 #if JPEG_LIB_VERSION >= 80 0738 /* These fields are derived from Se of first SOS marker. 0739 */ 0740 int block_size; /* the basic DCT block size: 1..16 */ 0741 const int *natural_order; /* natural-order position array for entropy decode */ 0742 int lim_Se; /* min( Se, DCTSIZE2-1 ) for entropy decode */ 0743 #endif 0744 0745 /* This field is shared between entropy decoder and marker parser. 0746 * It is either zero or the code of a JPEG marker that has been 0747 * read from the data source, but has not yet been processed. 0748 */ 0749 int unread_marker; 0750 0751 /* 0752 * Links to decompression subobjects (methods, private variables of modules) 0753 */ 0754 struct jpeg_decomp_master *master; 0755 struct jpeg_d_main_controller *main; 0756 struct jpeg_d_coef_controller *coef; 0757 struct jpeg_d_post_controller *post; 0758 struct jpeg_input_controller *inputctl; 0759 struct jpeg_marker_reader *marker; 0760 struct jpeg_entropy_decoder *entropy; 0761 struct jpeg_inverse_dct *idct; 0762 struct jpeg_upsampler *upsample; 0763 struct jpeg_color_deconverter *cconvert; 0764 struct jpeg_color_quantizer *cquantize; 0765 }; 0766 0767 0768 /* "Object" declarations for JPEG modules that may be supplied or called 0769 * directly by the surrounding application. 0770 * As with all objects in the JPEG library, these structs only define the 0771 * publicly visible methods and state variables of a module. Additional 0772 * private fields may exist after the public ones. 0773 */ 0774 0775 0776 /* Error handler object */ 0777 0778 struct jpeg_error_mgr { 0779 /* Error exit handler: does not return to caller */ 0780 void (*error_exit) (j_common_ptr cinfo); 0781 /* Conditionally emit a trace or warning message */ 0782 void (*emit_message) (j_common_ptr cinfo, int msg_level); 0783 /* Routine that actually outputs a trace or error message */ 0784 void (*output_message) (j_common_ptr cinfo); 0785 /* Format a message string for the most recent JPEG error or message */ 0786 void (*format_message) (j_common_ptr cinfo, char *buffer); 0787 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */ 0788 /* Reset error state variables at start of a new image */ 0789 void (*reset_error_mgr) (j_common_ptr cinfo); 0790 0791 /* The message ID code and any parameters are saved here. 0792 * A message can have one string parameter or up to 8 int parameters. 0793 */ 0794 int msg_code; 0795 #define JMSG_STR_PARM_MAX 80 0796 union { 0797 int i[8]; 0798 char s[JMSG_STR_PARM_MAX]; 0799 } msg_parm; 0800 0801 /* Standard state variables for error facility */ 0802 0803 int trace_level; /* max msg_level that will be displayed */ 0804 0805 /* For recoverable corrupt-data errors, we emit a warning message, 0806 * but keep going unless emit_message chooses to abort. emit_message 0807 * should count warnings in num_warnings. The surrounding application 0808 * can check for bad data by seeing if num_warnings is nonzero at the 0809 * end of processing. 0810 */ 0811 long num_warnings; /* number of corrupt-data warnings */ 0812 0813 /* These fields point to the table(s) of error message strings. 0814 * An application can change the table pointer to switch to a different 0815 * message list (typically, to change the language in which errors are 0816 * reported). Some applications may wish to add additional error codes 0817 * that will be handled by the JPEG library error mechanism; the second 0818 * table pointer is used for this purpose. 0819 * 0820 * First table includes all errors generated by JPEG library itself. 0821 * Error code 0 is reserved for a "no such error string" message. 0822 */ 0823 const char * const *jpeg_message_table; /* Library errors */ 0824 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */ 0825 /* Second table can be added by application (see cjpeg/djpeg for example). 0826 * It contains strings numbered first_addon_message..last_addon_message. 0827 */ 0828 const char * const *addon_message_table; /* Non-library errors */ 0829 int first_addon_message; /* code for first string in addon table */ 0830 int last_addon_message; /* code for last string in addon table */ 0831 }; 0832 0833 0834 /* Progress monitor object */ 0835 0836 struct jpeg_progress_mgr { 0837 void (*progress_monitor) (j_common_ptr cinfo); 0838 0839 long pass_counter; /* work units completed in this pass */ 0840 long pass_limit; /* total number of work units in this pass */ 0841 int completed_passes; /* passes completed so far */ 0842 int total_passes; /* total number of passes expected */ 0843 }; 0844 0845 0846 /* Data destination object for compression */ 0847 0848 struct jpeg_destination_mgr { 0849 JOCTET *next_output_byte; /* => next byte to write in buffer */ 0850 size_t free_in_buffer; /* # of byte spaces remaining in buffer */ 0851 0852 void (*init_destination) (j_compress_ptr cinfo); 0853 boolean (*empty_output_buffer) (j_compress_ptr cinfo); 0854 void (*term_destination) (j_compress_ptr cinfo); 0855 }; 0856 0857 0858 /* Data source object for decompression */ 0859 0860 struct jpeg_source_mgr { 0861 const JOCTET *next_input_byte; /* => next byte to read from buffer */ 0862 size_t bytes_in_buffer; /* # of bytes remaining in buffer */ 0863 0864 void (*init_source) (j_decompress_ptr cinfo); 0865 boolean (*fill_input_buffer) (j_decompress_ptr cinfo); 0866 void (*skip_input_data) (j_decompress_ptr cinfo, long num_bytes); 0867 boolean (*resync_to_restart) (j_decompress_ptr cinfo, int desired); 0868 void (*term_source) (j_decompress_ptr cinfo); 0869 }; 0870 0871 0872 /* Memory manager object. 0873 * Allocates "small" objects (a few K total), "large" objects (tens of K), 0874 * and "really big" objects (virtual arrays with backing store if needed). 0875 * The memory manager does not allow individual objects to be freed; rather, 0876 * each created object is assigned to a pool, and whole pools can be freed 0877 * at once. This is faster and more convenient than remembering exactly what 0878 * to free, especially where malloc()/free() are not too speedy. 0879 * NB: alloc routines never return NULL. They exit to error_exit if not 0880 * successful. 0881 */ 0882 0883 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */ 0884 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */ 0885 #define JPOOL_NUMPOOLS 2 0886 0887 typedef struct jvirt_sarray_control *jvirt_sarray_ptr; 0888 typedef struct jvirt_barray_control *jvirt_barray_ptr; 0889 0890 0891 struct jpeg_memory_mgr { 0892 /* Method pointers */ 0893 void *(*alloc_small) (j_common_ptr cinfo, int pool_id, size_t sizeofobject); 0894 void *(*alloc_large) (j_common_ptr cinfo, int pool_id, 0895 size_t sizeofobject); 0896 /* If cinfo->data_precision is 12 or 16, then this method and the 0897 * access_virt_sarray method actually return a J12SAMPARRAY or a 0898 * J16SAMPARRAY, so callers must type-cast the return value in order to 0899 * read/write 12-bit or 16-bit samples from/to the array. 0900 */ 0901 JSAMPARRAY (*alloc_sarray) (j_common_ptr cinfo, int pool_id, 0902 JDIMENSION samplesperrow, JDIMENSION numrows); 0903 JBLOCKARRAY (*alloc_barray) (j_common_ptr cinfo, int pool_id, 0904 JDIMENSION blocksperrow, JDIMENSION numrows); 0905 jvirt_sarray_ptr (*request_virt_sarray) (j_common_ptr cinfo, int pool_id, 0906 boolean pre_zero, 0907 JDIMENSION samplesperrow, 0908 JDIMENSION numrows, 0909 JDIMENSION maxaccess); 0910 jvirt_barray_ptr (*request_virt_barray) (j_common_ptr cinfo, int pool_id, 0911 boolean pre_zero, 0912 JDIMENSION blocksperrow, 0913 JDIMENSION numrows, 0914 JDIMENSION maxaccess); 0915 void (*realize_virt_arrays) (j_common_ptr cinfo); 0916 JSAMPARRAY (*access_virt_sarray) (j_common_ptr cinfo, jvirt_sarray_ptr ptr, 0917 JDIMENSION start_row, JDIMENSION num_rows, 0918 boolean writable); 0919 JBLOCKARRAY (*access_virt_barray) (j_common_ptr cinfo, jvirt_barray_ptr ptr, 0920 JDIMENSION start_row, JDIMENSION num_rows, 0921 boolean writable); 0922 void (*free_pool) (j_common_ptr cinfo, int pool_id); 0923 void (*self_destruct) (j_common_ptr cinfo); 0924 0925 /* Limit on memory allocation for this JPEG object. (Note that this is 0926 * merely advisory, not a guaranteed maximum; it only affects the space 0927 * used for virtual-array buffers.) May be changed by outer application 0928 * after creating the JPEG object. 0929 */ 0930 long max_memory_to_use; 0931 0932 /* Maximum allocation request accepted by alloc_large. */ 0933 long max_alloc_chunk; 0934 }; 0935 0936 0937 /* Routine signature for application-supplied marker processing methods. 0938 * Need not pass marker code since it is stored in cinfo->unread_marker. 0939 */ 0940 typedef boolean (*jpeg_marker_parser_method) (j_decompress_ptr cinfo); 0941 0942 0943 /* Originally, this macro was used as a way of defining function prototypes 0944 * for both modern compilers as well as older compilers that did not support 0945 * prototype parameters. libjpeg-turbo has never supported these older, 0946 * non-ANSI compilers, but the macro is still included because there is some 0947 * software out there that uses it. 0948 */ 0949 0950 #define JPP(arglist) arglist 0951 0952 0953 /* Default error-management setup */ 0954 EXTERN(struct jpeg_error_mgr *) jpeg_std_error(struct jpeg_error_mgr *err); 0955 0956 /* Initialization of JPEG compression objects. 0957 * jpeg_create_compress() and jpeg_create_decompress() are the exported 0958 * names that applications should call. These expand to calls on 0959 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information 0960 * passed for version mismatch checking. 0961 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx. 0962 */ 0963 #define jpeg_create_compress(cinfo) \ 0964 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \ 0965 (size_t)sizeof(struct jpeg_compress_struct)) 0966 #define jpeg_create_decompress(cinfo) \ 0967 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \ 0968 (size_t)sizeof(struct jpeg_decompress_struct)) 0969 EXTERN(void) jpeg_CreateCompress(j_compress_ptr cinfo, int version, 0970 size_t structsize); 0971 EXTERN(void) jpeg_CreateDecompress(j_decompress_ptr cinfo, int version, 0972 size_t structsize); 0973 /* Destruction of JPEG compression objects */ 0974 EXTERN(void) jpeg_destroy_compress(j_compress_ptr cinfo); 0975 EXTERN(void) jpeg_destroy_decompress(j_decompress_ptr cinfo); 0976 0977 /* Standard data source and destination managers: stdio streams. */ 0978 /* Caller is responsible for opening the file before and closing after. */ 0979 EXTERN(void) jpeg_stdio_dest(j_compress_ptr cinfo, FILE *outfile); 0980 EXTERN(void) jpeg_stdio_src(j_decompress_ptr cinfo, FILE *infile); 0981 0982 /* Data source and destination managers: memory buffers. */ 0983 EXTERN(void) jpeg_mem_dest(j_compress_ptr cinfo, unsigned char **outbuffer, 0984 unsigned long *outsize); 0985 EXTERN(void) jpeg_mem_src(j_decompress_ptr cinfo, 0986 const unsigned char *inbuffer, unsigned long insize); 0987 0988 /* Default parameter setup for compression */ 0989 EXTERN(void) jpeg_set_defaults(j_compress_ptr cinfo); 0990 /* Compression parameter setup aids */ 0991 EXTERN(void) jpeg_set_colorspace(j_compress_ptr cinfo, 0992 J_COLOR_SPACE colorspace); 0993 EXTERN(void) jpeg_default_colorspace(j_compress_ptr cinfo); 0994 EXTERN(void) jpeg_set_quality(j_compress_ptr cinfo, int quality, 0995 boolean force_baseline); 0996 EXTERN(void) jpeg_set_linear_quality(j_compress_ptr cinfo, int scale_factor, 0997 boolean force_baseline); 0998 #if JPEG_LIB_VERSION >= 70 0999 EXTERN(void) jpeg_default_qtables(j_compress_ptr cinfo, 1000 boolean force_baseline); 1001 #endif 1002 EXTERN(void) jpeg_add_quant_table(j_compress_ptr cinfo, int which_tbl, 1003 const unsigned int *basic_table, 1004 int scale_factor, boolean force_baseline); 1005 EXTERN(int) jpeg_quality_scaling(int quality); 1006 EXTERN(void) jpeg_enable_lossless(j_compress_ptr cinfo, 1007 int predictor_selection_value, 1008 int point_transform); 1009 EXTERN(void) jpeg_simple_progression(j_compress_ptr cinfo); 1010 EXTERN(void) jpeg_suppress_tables(j_compress_ptr cinfo, boolean suppress); 1011 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table(j_common_ptr cinfo); 1012 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table(j_common_ptr cinfo); 1013 1014 /* Main entry points for compression */ 1015 EXTERN(void) jpeg_start_compress(j_compress_ptr cinfo, 1016 boolean write_all_tables); 1017 EXTERN(JDIMENSION) jpeg_write_scanlines(j_compress_ptr cinfo, 1018 JSAMPARRAY scanlines, 1019 JDIMENSION num_lines); 1020 EXTERN(JDIMENSION) jpeg12_write_scanlines(j_compress_ptr cinfo, 1021 J12SAMPARRAY scanlines, 1022 JDIMENSION num_lines); 1023 EXTERN(JDIMENSION) jpeg16_write_scanlines(j_compress_ptr cinfo, 1024 J16SAMPARRAY scanlines, 1025 JDIMENSION num_lines); 1026 EXTERN(void) jpeg_finish_compress(j_compress_ptr cinfo); 1027 1028 #if JPEG_LIB_VERSION >= 70 1029 /* Precalculate JPEG dimensions for current compression parameters. */ 1030 EXTERN(void) jpeg_calc_jpeg_dimensions(j_compress_ptr cinfo); 1031 #endif 1032 1033 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */ 1034 EXTERN(JDIMENSION) jpeg_write_raw_data(j_compress_ptr cinfo, JSAMPIMAGE data, 1035 JDIMENSION num_lines); 1036 EXTERN(JDIMENSION) jpeg12_write_raw_data(j_compress_ptr cinfo, 1037 J12SAMPIMAGE data, 1038 JDIMENSION num_lines); 1039 1040 /* Write a special marker. See libjpeg.txt concerning safe usage. */ 1041 EXTERN(void) jpeg_write_marker(j_compress_ptr cinfo, int marker, 1042 const JOCTET *dataptr, unsigned int datalen); 1043 /* Same, but piecemeal. */ 1044 EXTERN(void) jpeg_write_m_header(j_compress_ptr cinfo, int marker, 1045 unsigned int datalen); 1046 EXTERN(void) jpeg_write_m_byte(j_compress_ptr cinfo, int val); 1047 1048 /* Alternate compression function: just write an abbreviated table file */ 1049 EXTERN(void) jpeg_write_tables(j_compress_ptr cinfo); 1050 1051 /* Write ICC profile. See libjpeg.txt for usage information. */ 1052 EXTERN(void) jpeg_write_icc_profile(j_compress_ptr cinfo, 1053 const JOCTET *icc_data_ptr, 1054 unsigned int icc_data_len); 1055 1056 1057 /* Decompression startup: read start of JPEG datastream to see what's there */ 1058 EXTERN(int) jpeg_read_header(j_decompress_ptr cinfo, boolean require_image); 1059 /* Return value is one of: */ 1060 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */ 1061 #define JPEG_HEADER_OK 1 /* Found valid image datastream */ 1062 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */ 1063 /* If you pass require_image = TRUE (normal case), you need not check for 1064 * a TABLES_ONLY return code; an abbreviated file will cause an error exit. 1065 * JPEG_SUSPENDED is only possible if you use a data source module that can 1066 * give a suspension return (the stdio source module doesn't). 1067 */ 1068 1069 /* Main entry points for decompression */ 1070 EXTERN(boolean) jpeg_start_decompress(j_decompress_ptr cinfo); 1071 EXTERN(JDIMENSION) jpeg_read_scanlines(j_decompress_ptr cinfo, 1072 JSAMPARRAY scanlines, 1073 JDIMENSION max_lines); 1074 EXTERN(JDIMENSION) jpeg12_read_scanlines(j_decompress_ptr cinfo, 1075 J12SAMPARRAY scanlines, 1076 JDIMENSION max_lines); 1077 EXTERN(JDIMENSION) jpeg16_read_scanlines(j_decompress_ptr cinfo, 1078 J16SAMPARRAY scanlines, 1079 JDIMENSION max_lines); 1080 EXTERN(JDIMENSION) jpeg_skip_scanlines(j_decompress_ptr cinfo, 1081 JDIMENSION num_lines); 1082 EXTERN(JDIMENSION) jpeg12_skip_scanlines(j_decompress_ptr cinfo, 1083 JDIMENSION num_lines); 1084 EXTERN(void) jpeg_crop_scanline(j_decompress_ptr cinfo, JDIMENSION *xoffset, 1085 JDIMENSION *width); 1086 EXTERN(void) jpeg12_crop_scanline(j_decompress_ptr cinfo, JDIMENSION *xoffset, 1087 JDIMENSION *width); 1088 EXTERN(boolean) jpeg_finish_decompress(j_decompress_ptr cinfo); 1089 1090 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */ 1091 EXTERN(JDIMENSION) jpeg_read_raw_data(j_decompress_ptr cinfo, JSAMPIMAGE data, 1092 JDIMENSION max_lines); 1093 EXTERN(JDIMENSION) jpeg12_read_raw_data(j_decompress_ptr cinfo, 1094 J12SAMPIMAGE data, 1095 JDIMENSION max_lines); 1096 1097 /* Additional entry points for buffered-image mode. */ 1098 EXTERN(boolean) jpeg_has_multiple_scans(j_decompress_ptr cinfo); 1099 EXTERN(boolean) jpeg_start_output(j_decompress_ptr cinfo, int scan_number); 1100 EXTERN(boolean) jpeg_finish_output(j_decompress_ptr cinfo); 1101 EXTERN(boolean) jpeg_input_complete(j_decompress_ptr cinfo); 1102 EXTERN(void) jpeg_new_colormap(j_decompress_ptr cinfo); 1103 EXTERN(int) jpeg_consume_input(j_decompress_ptr cinfo); 1104 /* Return value is one of: */ 1105 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */ 1106 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */ 1107 #define JPEG_REACHED_EOI 2 /* Reached end of image */ 1108 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */ 1109 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */ 1110 1111 /* Precalculate output dimensions for current decompression parameters. */ 1112 #if JPEG_LIB_VERSION >= 80 1113 EXTERN(void) jpeg_core_output_dimensions(j_decompress_ptr cinfo); 1114 #endif 1115 EXTERN(void) jpeg_calc_output_dimensions(j_decompress_ptr cinfo); 1116 1117 /* Control saving of COM and APPn markers into marker_list. */ 1118 EXTERN(void) jpeg_save_markers(j_decompress_ptr cinfo, int marker_code, 1119 unsigned int length_limit); 1120 1121 /* Install a special processing method for COM or APPn markers. */ 1122 EXTERN(void) jpeg_set_marker_processor(j_decompress_ptr cinfo, 1123 int marker_code, 1124 jpeg_marker_parser_method routine); 1125 1126 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */ 1127 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients(j_decompress_ptr cinfo); 1128 EXTERN(void) jpeg_write_coefficients(j_compress_ptr cinfo, 1129 jvirt_barray_ptr *coef_arrays); 1130 EXTERN(void) jpeg_copy_critical_parameters(j_decompress_ptr srcinfo, 1131 j_compress_ptr dstinfo); 1132 1133 /* If you choose to abort compression or decompression before completing 1134 * jpeg_finish_(de)compress, then you need to clean up to release memory, 1135 * temporary files, etc. You can just call jpeg_destroy_(de)compress 1136 * if you're done with the JPEG object, but if you want to clean it up and 1137 * reuse it, call this: 1138 */ 1139 EXTERN(void) jpeg_abort_compress(j_compress_ptr cinfo); 1140 EXTERN(void) jpeg_abort_decompress(j_decompress_ptr cinfo); 1141 1142 /* Generic versions of jpeg_abort and jpeg_destroy that work on either 1143 * flavor of JPEG object. These may be more convenient in some places. 1144 */ 1145 EXTERN(void) jpeg_abort(j_common_ptr cinfo); 1146 EXTERN(void) jpeg_destroy(j_common_ptr cinfo); 1147 1148 /* Default restart-marker-resync procedure for use by data source modules */ 1149 EXTERN(boolean) jpeg_resync_to_restart(j_decompress_ptr cinfo, int desired); 1150 1151 /* Read ICC profile. See libjpeg.txt for usage information. */ 1152 EXTERN(boolean) jpeg_read_icc_profile(j_decompress_ptr cinfo, 1153 JOCTET **icc_data_ptr, 1154 unsigned int *icc_data_len); 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 */
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