00001 /* 00002 * jpeglib.h 00003 * 00004 * Copyright (C) 1991-1998, Thomas G. Lane. 00005 * This file is part of the Independent JPEG Group's software. 00006 * For conditions of distribution and use, see the accompanying README file. 00007 * 00008 * This file defines the application interface for the JPEG library. 00009 * Most applications using the library need only include this file, 00010 * and perhaps jerror.h if they want to know the exact error codes. 00011 */ 00012 00013 #ifndef JPEGLIB_H 00014 #define JPEGLIB_H 00015 00016 /* 00017 * First we include the configuration files that record how this 00018 * installation of the JPEG library is set up. jconfig.h can be 00019 * generated automatically for many systems. jmorecfg.h contains 00020 * manual configuration options that most people need not worry about. 00021 */ 00022 00023 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */ 00024 #include "jconfig8.h" /* widely used configuration options */ 00025 #endif 00026 #include "jmorecfg8.h" /* seldom changed options */ 00027 00028 00029 /* Version ID for the JPEG library. 00030 * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60". 00031 */ 00032 00033 #define JPEG_LIB_VERSION 62 /* Version 6b */ 00034 00035 00036 /* Various constants determining the sizes of things. 00037 * All of these are specified by the JPEG standard, so don't change them 00038 * if you want to be compatible. 00039 */ 00040 00041 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */ 00042 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */ 00043 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */ 00044 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */ 00045 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */ 00046 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */ 00047 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */ 00048 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard; 00049 * the PostScript DCT filter can emit files with many more than 10 data units 00050 * per MCU. 00051 * If you happen to run across such a file, you can up D_MAX_DATA_UNITS_IN_MCU 00052 * to handle it. We even let you do this from the jconfig.h file. However, 00053 * we strongly discourage changing C_MAX_DATA_UNITS_IN_MCU; just because Adobe 00054 * sometimes emits noncompliant files doesn't mean you should too. 00055 */ 00056 #define C_MAX_DATA_UNITS_IN_MCU 10 /* compressor's limit on data units/MCU */ 00057 #ifndef D_MAX_DATA_UNITS_IN_MCU 00058 #define D_MAX_DATA_UNITS_IN_MCU 10 /* decompressor's limit on data units/MCU */ 00059 #endif 00060 00061 00062 /* Data structures for images (arrays of samples and of DCT coefficients). 00063 * On 80x86 machines, the image arrays are too big for near pointers, 00064 * but the pointer arrays can fit in near memory. 00065 */ 00066 00067 typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */ 00068 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ 00069 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ 00070 00071 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ 00072 typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */ 00073 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ 00074 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ 00075 00076 typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */ 00077 00078 typedef JDIFF FAR *JDIFFROW; /* pointer to one row of difference values */ 00079 typedef JDIFFROW *JDIFFARRAY; /* ptr to some rows (a 2-D diff array) */ 00080 typedef JDIFFARRAY *JDIFFIMAGE; /* a 3-D diff array: top index is color */ 00081 00082 00083 /* Types for JPEG compression parameters and working tables. */ 00084 00085 00086 /* DCT coefficient quantization tables. */ 00087 00088 typedef struct { 00089 /* This array gives the coefficient quantizers in natural array order 00090 * (not the zigzag order in which they are stored in a JPEG DQT marker). 00091 * CAUTION: IJG versions prior to v6a kept this array in zigzag order. 00092 */ 00093 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */ 00094 /* This field is used only during compression. It's initialized FALSE when 00095 * the table is created, and set TRUE when it's been output to the file. 00096 * You could suppress output of a table by setting this to TRUE. 00097 * (See jpeg_suppress_tables for an example.) 00098 */ 00099 boolean sent_table; /* TRUE when table has been output */ 00100 } JQUANT_TBL; 00101 00102 00103 /* Huffman coding tables. */ 00104 00105 typedef struct { 00106 /* These two fields directly represent the contents of a JPEG DHT marker */ 00107 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ 00108 /* length k bits; bits[0] is unused */ 00109 UINT8 huffval[256]; /* The symbols, in order of incr code length */ 00110 /* This field is used only during compression. It's initialized FALSE when 00111 * the table is created, and set TRUE when it's been output to the file. 00112 * You could suppress output of a table by setting this to TRUE. 00113 * (See jpeg_suppress_tables for an example.) 00114 */ 00115 boolean sent_table; /* TRUE when table has been output */ 00116 } JHUFF_TBL; 00117 00118 00119 /* Basic info about one component (color channel). */ 00120 00121 typedef struct { 00122 /* These values are fixed over the whole image. */ 00123 /* For compression, they must be supplied by parameter setup; */ 00124 /* for decompression, they are read from the SOF marker. */ 00125 int component_id; /* identifier for this component (0..255) */ 00126 int component_index; /* its index in SOF or cinfo->comp_info[] */ 00127 int h_samp_factor; /* horizontal sampling factor (1..4) */ 00128 int v_samp_factor; /* vertical sampling factor (1..4) */ 00129 int quant_tbl_no; /* quantization table selector (0..3) */ 00130 /* These values may vary between scans. */ 00131 /* For compression, they must be supplied by parameter setup; */ 00132 /* for decompression, they are read from the SOS marker. */ 00133 /* The decompressor output side may not use these variables. */ 00134 int dc_tbl_no; /* DC entropy table selector (0..3) */ 00135 int ac_tbl_no; /* AC entropy table selector (0..3) */ 00136 00137 /* Remaining fields should be treated as private by applications. */ 00138 00139 /* These values are computed during compression or decompression startup: */ 00140 /* Component's size in data units. 00141 * Any dummy data units added to complete an MCU are not counted; therefore 00142 * these values do not depend on whether a scan is interleaved or not. 00143 */ 00144 JDIMENSION width_in_data_units; 00145 JDIMENSION height_in_data_units; 00146 /* Size of a data unit in/output by the codec (in samples). Always 00147 * data_unit for compression. For decompression this is the size of the 00148 * output from one data_unit, reflecting any processing performed by the 00149 * codec. For example, in the DCT-based codec, scaling may be applied 00150 * during the IDCT step. Values of 1,2,4,8 are likely to be supported. 00151 * Note that different components may have different codec_data_unit sizes. 00152 */ 00153 int codec_data_unit; 00154 /* The downsampled dimensions are the component's actual, unpadded number 00155 * of samples at the main buffer (preprocessing/compression interface), thus 00156 * downsampled_width = ceil(image_width * Hi/Hmax) 00157 * and similarly for height. For decompression, codec-based processing is 00158 * included (ie, IDCT scaling), so 00159 * downsampled_width = ceil(image_width * Hi/Hmax * codec_data_unit/data_unit) 00160 */ 00161 JDIMENSION downsampled_width; /* actual width in samples */ 00162 JDIMENSION downsampled_height; /* actual height in samples */ 00163 /* This flag is used only for decompression. In cases where some of the 00164 * components will be ignored (eg grayscale output from YCbCr image), 00165 * we can skip most computations for the unused components. 00166 */ 00167 boolean component_needed; /* do we need the value of this component? */ 00168 00169 /* These values are computed before starting a scan of the component. */ 00170 /* The decompressor output side may not use these variables. */ 00171 int MCU_width; /* number of data units per MCU, horizontally */ 00172 int MCU_height; /* number of data units per MCU, vertically */ 00173 int MCU_data_units; /* MCU_width * MCU_height */ 00174 int MCU_sample_width; /* MCU width in samples, MCU_width*codec_data_unit */ 00175 int last_col_width; /* # of non-dummy data_units across in last MCU */ 00176 int last_row_height; /* # of non-dummy data_units down in last MCU */ 00177 00178 /* Saved quantization table for component; NULL if none yet saved. 00179 * See jdinput.c comments about the need for this information. 00180 * This field is currently used only for decompression. 00181 */ 00182 JQUANT_TBL * quant_table; 00183 00184 /* Private per-component storage for DCT or IDCT subsystem. */ 00185 void * dct_table; 00186 } jpeg_component_info; 00187 00188 00189 /* The script for encoding a multiple-scan file is an array of these: */ 00190 00191 typedef struct { 00192 int comps_in_scan; /* number of components encoded in this scan */ 00193 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */ 00194 int Ss, Se; /* progressive JPEG spectral selection parms 00195 lossless JPEG predictor select parm (Ss) */ 00196 int Ah, Al; /* progressive JPEG successive approx. parms 00197 lossless JPEG point transform parm (Al) */ 00198 } jpeg_scan_info; 00199 00200 /* The decompressor can save APPn and COM markers in a list of these: */ 00201 00202 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr; 00203 00204 struct jpeg_marker_struct { 00205 jpeg_saved_marker_ptr next; /* next in list, or NULL */ 00206 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */ 00207 unsigned int original_length; /* # bytes of data in the file */ 00208 unsigned int data_length; /* # bytes of data saved at data[] */ 00209 JOCTET FAR * data; /* the data contained in the marker */ 00210 /* the marker length word is not counted in data_length or original_length */ 00211 }; 00212 00213 /* Known codec processes. */ 00214 00215 typedef enum { 00216 JPROC_SEQUENTIAL, /* baseline/extended sequential DCT */ 00217 JPROC_PROGRESSIVE, /* progressive DCT */ 00218 JPROC_LOSSLESS /* lossless (sequential) */ 00219 } J_CODEC_PROCESS; 00220 00221 /* Known color spaces. */ 00222 00223 typedef enum { 00224 JCS_UNKNOWN, /* error/unspecified */ 00225 JCS_GRAYSCALE, /* monochrome */ 00226 JCS_RGB, /* red/green/blue */ 00227 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ 00228 JCS_CMYK, /* C/M/Y/K */ 00229 JCS_YCCK /* Y/Cb/Cr/K */ 00230 } J_COLOR_SPACE; 00231 00232 /* DCT/IDCT algorithm options. */ 00233 00234 typedef enum { 00235 JDCT_ISLOW, /* slow but accurate integer algorithm */ 00236 JDCT_IFAST, /* faster, less accurate integer method */ 00237 JDCT_FLOAT /* floating-point: accurate, fast on fast HW */ 00238 } J_DCT_METHOD; 00239 00240 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */ 00241 #define JDCT_DEFAULT JDCT_ISLOW 00242 #endif 00243 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */ 00244 #define JDCT_FASTEST JDCT_IFAST 00245 #endif 00246 00247 /* Dithering options for decompression. */ 00248 00249 typedef enum { 00250 JDITHER_NONE, /* no dithering */ 00251 JDITHER_ORDERED, /* simple ordered dither */ 00252 JDITHER_FS /* Floyd-Steinberg error diffusion dither */ 00253 } J_DITHER_MODE; 00254 00255 00256 /* Common fields between JPEG compression and decompression master structs. */ 00257 00258 #define jpeg_common_fields \ 00259 struct jpeg_error_mgr * err; /* Error handler module */\ 00260 struct jpeg_memory_mgr * mem; /* Memory manager module */\ 00261 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\ 00262 void * client_data; /* Available for use by application */\ 00263 boolean is_decompressor; /* So common code can tell which is which */\ 00264 int global_state /* For checking call sequence validity */ 00265 00266 /* Routines that are to be used by both halves of the library are declared 00267 * to receive a pointer to this structure. There are no actual instances of 00268 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct. 00269 */ 00270 struct jpeg_common_struct { 00271 jpeg_common_fields; /* Fields common to both master struct types */ 00272 /* Additional fields follow in an actual jpeg_compress_struct or 00273 * jpeg_decompress_struct. All three structs must agree on these 00274 * initial fields! (This would be a lot cleaner in C++.) 00275 */ 00276 }; 00277 00278 typedef struct jpeg_common_struct * j_common_ptr; 00279 typedef struct jpeg_compress_struct * j_compress_ptr; 00280 typedef struct jpeg_decompress_struct * j_decompress_ptr; 00281 00282 00283 /* Master record for a compression instance */ 00284 00285 struct jpeg_compress_struct { 00286 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */ 00287 00288 /* Destination for compressed data */ 00289 struct jpeg_destination_mgr * dest; 00290 00291 /* Description of source image --- these fields must be filled in by 00292 * outer application before starting compression. in_color_space must 00293 * be correct before you can even call jpeg_set_defaults(). 00294 */ 00295 00296 JDIMENSION image_width; /* input image width */ 00297 JDIMENSION image_height; /* input image height */ 00298 int input_components; /* # of color components in input image */ 00299 J_COLOR_SPACE in_color_space; /* colorspace of input image */ 00300 00301 double input_gamma; /* image gamma of input image */ 00302 00303 /* Compression parameters --- these fields must be set before calling 00304 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to 00305 * initialize everything to reasonable defaults, then changing anything 00306 * the application specifically wants to change. That way you won't get 00307 * burnt when new parameters are added. Also note that there are several 00308 * helper routines to simplify changing parameters. 00309 */ 00310 00311 boolean lossless; /* TRUE=lossless encoding, FALSE=lossy */ 00312 00313 int data_precision; /* bits of precision in image data */ 00314 00315 int num_components; /* # of color components in JPEG image */ 00316 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 00317 00318 jpeg_component_info * comp_info; 00319 /* comp_info[i] describes component that appears i'th in SOF */ 00320 00321 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 00322 /* ptrs to coefficient quantization tables, or NULL if not defined */ 00323 00324 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 00325 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 00326 /* ptrs to Huffman coding tables, or NULL if not defined */ 00327 00328 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 00329 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 00330 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 00331 00332 int num_scans; /* # of entries in scan_info array */ 00333 const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */ 00334 /* The default value of scan_info is NULL, which causes a single-scan 00335 * sequential JPEG file to be emitted. To create a multi-scan file, 00336 * set num_scans and scan_info to point to an array of scan definitions. 00337 */ 00338 00339 boolean raw_data_in; /* TRUE=caller supplies downsampled data */ 00340 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 00341 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ 00342 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 00343 int smoothing_factor; /* 1..100, or 0 for no input smoothing */ 00344 J_DCT_METHOD dct_method; /* DCT algorithm selector */ 00345 00346 /* The restart interval can be specified in absolute MCUs by setting 00347 * restart_interval, or in MCU rows by setting restart_in_rows 00348 * (in which case the correct restart_interval will be figured 00349 * for each scan). 00350 */ 00351 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */ 00352 int restart_in_rows; /* if > 0, MCU rows per restart interval */ 00353 00354 /* Parameters controlling emission of special markers. */ 00355 00356 boolean write_JFIF_header; /* should a JFIF marker be written? */ 00357 UINT8 JFIF_major_version; /* What to write for the JFIF version number */ 00358 UINT8 JFIF_minor_version; 00359 /* These three values are not used by the JPEG code, merely copied */ 00360 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ 00361 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ 00362 /* ratio is defined by X_density/Y_density even when density_unit=0. */ 00363 UINT8 density_unit; /* JFIF code for pixel size units */ 00364 UINT16 X_density; /* Horizontal pixel density */ 00365 UINT16 Y_density; /* Vertical pixel density */ 00366 boolean write_Adobe_marker; /* should an Adobe marker be written? */ 00367 00368 /* State variable: index of next scanline to be written to 00369 * jpeg_write_scanlines(). Application may use this to control its 00370 * processing loop, e.g., "while (next_scanline < image_height)". 00371 */ 00372 00373 JDIMENSION next_scanline; /* 0 .. image_height-1 */ 00374 00375 /* Remaining fields are known throughout compressor, but generally 00376 * should not be touched by a surrounding application. 00377 */ 00378 00379 /* 00380 * These fields are computed during compression startup 00381 */ 00382 int data_unit; /* size of data unit in samples */ 00383 J_CODEC_PROCESS process; /* encoding process of JPEG image */ 00384 00385 int max_h_samp_factor; /* largest h_samp_factor */ 00386 int max_v_samp_factor; /* largest v_samp_factor */ 00387 00388 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to codec */ 00389 /* The codec receives data in units of MCU rows as defined for fully 00390 * interleaved scans (whether the JPEG file is interleaved or not). 00391 * There are v_samp_factor * data_unit sample rows of each component in an 00392 * "iMCU" (interleaved MCU) row. 00393 */ 00394 00395 /* 00396 * These fields are valid during any one scan. 00397 * They describe the components and MCUs actually appearing in the scan. 00398 */ 00399 int comps_in_scan; /* # of JPEG components in this scan */ 00400 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 00401 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 00402 00403 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 00404 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 00405 00406 int data_units_in_MCU; /* # of data units per MCU */ 00407 int MCU_membership[C_MAX_DATA_UNITS_IN_MCU]; 00408 /* MCU_membership[i] is index in cur_comp_info of component owning */ 00409 /* i'th block in an MCU */ 00410 00411 int Ss, Se, Ah, Al; /* progressive/lossless JPEG parameters for scan */ 00412 00413 /* 00414 * Links to compression subobjects (methods and private variables of modules) 00415 */ 00416 struct jpeg_comp_master * master; 00417 struct jpeg_c_main_controller * main; 00418 struct jpeg_c_prep_controller * prep; 00419 struct jpeg_c_codec * codec; 00420 struct jpeg_marker_writer * marker; 00421 struct jpeg_color_converter * cconvert; 00422 struct jpeg_downsampler * downsample; 00423 jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */ 00424 int script_space_size; 00425 }; 00426 00427 00428 /* Master record for a decompression instance */ 00429 00430 struct jpeg_decompress_struct { 00431 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */ 00432 00433 /* Source of compressed data */ 00434 struct jpeg_source_mgr * src; 00435 00436 /* Basic description of image --- filled in by jpeg_read_header(). */ 00437 /* Application may inspect these values to decide how to process image. */ 00438 00439 JDIMENSION image_width; /* nominal image width (from SOF marker) */ 00440 JDIMENSION image_height; /* nominal image height */ 00441 int num_components; /* # of color components in JPEG image */ 00442 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ 00443 00444 /* Decompression processing parameters --- these fields must be set before 00445 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes 00446 * them to default values. 00447 */ 00448 00449 J_COLOR_SPACE out_color_space; /* colorspace for output */ 00450 00451 unsigned int scale_num, scale_denom; /* fraction by which to scale image */ 00452 00453 double output_gamma; /* image gamma wanted in output */ 00454 00455 boolean buffered_image; /* TRUE=multiple output passes */ 00456 boolean raw_data_out; /* TRUE=downsampled data wanted */ 00457 00458 J_DCT_METHOD dct_method; /* IDCT algorithm selector */ 00459 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */ 00460 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */ 00461 00462 boolean quantize_colors; /* TRUE=colormapped output wanted */ 00463 /* the following are ignored if not quantize_colors: */ 00464 J_DITHER_MODE dither_mode; /* type of color dithering to use */ 00465 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */ 00466 int desired_number_of_colors; /* max # colors to use in created colormap */ 00467 /* these are significant only in buffered-image mode: */ 00468 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */ 00469 boolean enable_external_quant;/* enable future use of external colormap */ 00470 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */ 00471 00472 /* Description of actual output image that will be returned to application. 00473 * These fields are computed by jpeg_start_decompress(). 00474 * You can also use jpeg_calc_output_dimensions() to determine these values 00475 * in advance of calling jpeg_start_decompress(). 00476 */ 00477 00478 JDIMENSION output_width; /* scaled image width */ 00479 JDIMENSION output_height; /* scaled image height */ 00480 int out_color_components; /* # of color components in out_color_space */ 00481 int output_components; /* # of color components returned */ 00482 /* output_components is 1 (a colormap index) when quantizing colors; 00483 * otherwise it equals out_color_components. 00484 */ 00485 int rec_outbuf_height; /* min recommended height of scanline buffer */ 00486 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows 00487 * high, space and time will be wasted due to unnecessary data copying. 00488 * Usually rec_outbuf_height will be 1 or 2, at most 4. 00489 */ 00490 00491 /* When quantizing colors, the output colormap is described by these fields. 00492 * The application can supply a colormap by setting colormap non-NULL before 00493 * calling jpeg_start_decompress; otherwise a colormap is created during 00494 * jpeg_start_decompress or jpeg_start_output. 00495 * The map has out_color_components rows and actual_number_of_colors columns. 00496 */ 00497 int actual_number_of_colors; /* number of entries in use */ 00498 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */ 00499 00500 /* State variables: these variables indicate the progress of decompression. 00501 * The application may examine these but must not modify them. 00502 */ 00503 00504 /* Row index of next scanline to be read from jpeg_read_scanlines(). 00505 * Application may use this to control its processing loop, e.g., 00506 * "while (output_scanline < output_height)". 00507 */ 00508 JDIMENSION output_scanline; /* 0 .. output_height-1 */ 00509 00510 /* Current input scan number and number of iMCU rows completed in scan. 00511 * These indicate the progress of the decompressor input side. 00512 */ 00513 int input_scan_number; /* Number of SOS markers seen so far */ 00514 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */ 00515 00516 /* The "output scan number" is the notional scan being displayed by the 00517 * output side. The decompressor will not allow output scan/row number 00518 * to get ahead of input scan/row, but it can fall arbitrarily far behind. 00519 */ 00520 int output_scan_number; /* Nominal scan number being displayed */ 00521 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */ 00522 00523 /* Current progression status. coef_bits[c][i] indicates the precision 00524 * with which component c's DCT coefficient i (in zigzag order) is known. 00525 * It is -1 when no data has yet been received, otherwise it is the point 00526 * transform (shift) value for the most recent scan of the coefficient 00527 * (thus, 0 at completion of the progression). 00528 * This pointer is NULL when reading a non-progressive file. 00529 */ 00530 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */ 00531 00532 /* Internal JPEG parameters --- the application usually need not look at 00533 * these fields. Note that the decompressor output side may not use 00534 * any parameters that can change between scans. 00535 */ 00536 00537 /* Quantization and Huffman tables are carried forward across input 00538 * datastreams when processing abbreviated JPEG datastreams. 00539 */ 00540 00541 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; 00542 /* ptrs to coefficient quantization tables, or NULL if not defined */ 00543 00544 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; 00545 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; 00546 /* ptrs to Huffman coding tables, or NULL if not defined */ 00547 00548 /* These parameters are never carried across datastreams, since they 00549 * are given in SOF/SOS markers or defined to be reset by SOI. 00550 */ 00551 00552 int data_precision; /* bits of precision in image data */ 00553 00554 jpeg_component_info * comp_info; 00555 /* comp_info[i] describes component that appears i'th in SOF */ 00556 00557 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ 00558 00559 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ 00560 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ 00561 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ 00562 00563 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */ 00564 00565 /* These fields record data obtained from optional markers recognized by 00566 * the JPEG library. 00567 */ 00568 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */ 00569 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */ 00570 UINT8 JFIF_major_version; /* JFIF version number */ 00571 UINT8 JFIF_minor_version; 00572 UINT8 density_unit; /* JFIF code for pixel size units */ 00573 UINT16 X_density; /* Horizontal pixel density */ 00574 UINT16 Y_density; /* Vertical pixel density */ 00575 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */ 00576 UINT8 Adobe_transform; /* Color transform code from Adobe marker */ 00577 00578 boolean CCIR601_sampling; /* TRUE=first samples are cosited */ 00579 00580 /* Aside from the specific data retained from APPn markers known to the 00581 * library, the uninterpreted contents of any or all APPn and COM markers 00582 * can be saved in a list for examination by the application. 00583 */ 00584 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */ 00585 00586 /* Remaining fields are known throughout decompressor, but generally 00587 * should not be touched by a surrounding application. 00588 */ 00589 00590 /* 00591 * These fields are computed during decompression startup 00592 */ 00593 int data_unit; /* size of data unit in samples */ 00594 J_CODEC_PROCESS process; /* decoding process of JPEG image */ 00595 00596 int max_h_samp_factor; /* largest h_samp_factor */ 00597 int max_v_samp_factor; /* largest v_samp_factor */ 00598 00599 int min_codec_data_unit; /* smallest codec_data_unit of any component */ 00600 00601 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ 00602 /* The codec's input and output progress is measured in units of "iMCU" 00603 * (interleaved MCU) rows. These are the same as MCU rows in fully 00604 * interleaved JPEG scans, but are used whether the scan is interleaved 00605 * or not. We define an iMCU row as v_samp_factor data_unit rows of each 00606 * component. Therefore, the codec output contains 00607 * v_samp_factor*codec_data_unit sample rows of a component per iMCU row. 00608 */ 00609 00610 JSAMPLE * sample_range_limit; /* table for fast range-limiting */ 00611 00612 /* 00613 * These fields are valid during any one scan. 00614 * They describe the components and MCUs actually appearing in the scan. 00615 * Note that the decompressor output side must not use these fields. 00616 */ 00617 int comps_in_scan; /* # of JPEG components in this scan */ 00618 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; 00619 /* *cur_comp_info[i] describes component that appears i'th in SOS */ 00620 00621 JDIMENSION MCUs_per_row; /* # of MCUs across the image */ 00622 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ 00623 00624 int data_units_in_MCU; /* # of data _units per MCU */ 00625 int MCU_membership[D_MAX_DATA_UNITS_IN_MCU]; 00626 /* MCU_membership[i] is index in cur_comp_info of component owning */ 00627 /* i'th data unit in an MCU */ 00628 00629 int Ss, Se, Ah, Al; /* progressive/lossless JPEG parms for scan */ 00630 00631 /* This field is shared between entropy decoder and marker parser. 00632 * It is either zero or the code of a JPEG marker that has been 00633 * read from the data source, but has not yet been processed. 00634 */ 00635 int unread_marker; 00636 00637 /* 00638 * Links to decompression subobjects (methods, private variables of modules) 00639 */ 00640 struct jpeg_decomp_master * master; 00641 struct jpeg_d_main_controller * main; 00642 struct jpeg_d_codec * codec; 00643 struct jpeg_d_post_controller * post; 00644 struct jpeg_input_controller * inputctl; 00645 struct jpeg_marker_reader * marker; 00646 struct jpeg_upsampler * upsample; 00647 struct jpeg_color_deconverter * cconvert; 00648 struct jpeg_color_quantizer * cquantize; 00649 }; 00650 00651 00652 /* "Object" declarations for JPEG modules that may be supplied or called 00653 * directly by the surrounding application. 00654 * As with all objects in the JPEG library, these structs only define the 00655 * publicly visible methods and state variables of a module. Additional 00656 * private fields may exist after the public ones. 00657 */ 00658 00659 00660 /* Error handler object */ 00661 00662 struct jpeg_error_mgr { 00663 /* Error exit handler: does not return to caller */ 00664 JMETHOD(void, error_exit, (j_common_ptr cinfo)); 00665 /* Conditionally emit a trace or warning message */ 00666 JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level)); 00667 /* Routine that actually outputs a trace or error message */ 00668 JMETHOD(void, output_message, (j_common_ptr cinfo)); 00669 /* Format a message string for the most recent JPEG error or message */ 00670 JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer)); 00671 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */ 00672 /* Reset error state variables at start of a new image */ 00673 JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo)); 00674 00675 /* The message ID code and any parameters are saved here. 00676 * A message can have one string parameter or up to 8 int parameters. 00677 */ 00678 int msg_code; 00679 #define JMSG_STR_PARM_MAX 80 00680 union { 00681 int i[8]; 00682 char s[JMSG_STR_PARM_MAX]; 00683 } msg_parm; 00684 00685 /* Standard state variables for error facility */ 00686 00687 int trace_level; /* max msg_level that will be displayed */ 00688 00689 /* For recoverable corrupt-data errors, we emit a warning message, 00690 * but keep going unless emit_message chooses to abort. emit_message 00691 * should count warnings in num_warnings. The surrounding application 00692 * can check for bad data by seeing if num_warnings is nonzero at the 00693 * end of processing. 00694 */ 00695 long num_warnings; /* number of corrupt-data warnings */ 00696 00697 /* These fields point to the table(s) of error message strings. 00698 * An application can change the table pointer to switch to a different 00699 * message list (typically, to change the language in which errors are 00700 * reported). Some applications may wish to add additional error codes 00701 * that will be handled by the JPEG library error mechanism; the second 00702 * table pointer is used for this purpose. 00703 * 00704 * First table includes all errors generated by JPEG library itself. 00705 * Error code 0 is reserved for a "no such error string" message. 00706 */ 00707 const char * const * jpeg_message_table; /* Library errors */ 00708 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */ 00709 /* Second table can be added by application (see cjpeg/djpeg for example). 00710 * It contains strings numbered first_addon_message..last_addon_message. 00711 */ 00712 const char * const * addon_message_table; /* Non-library errors */ 00713 int first_addon_message; /* code for first string in addon table */ 00714 int last_addon_message; /* code for last string in addon table */ 00715 }; 00716 00717 00718 /* Progress monitor object */ 00719 00720 struct jpeg_progress_mgr { 00721 JMETHOD(void, progress_monitor, (j_common_ptr cinfo)); 00722 00723 long pass_counter; /* work units completed in this pass */ 00724 long pass_limit; /* total number of work units in this pass */ 00725 int completed_passes; /* passes completed so far */ 00726 int total_passes; /* total number of passes expected */ 00727 }; 00728 00729 00730 /* Data destination object for compression */ 00731 00732 struct jpeg_destination_mgr { 00733 JOCTET * next_output_byte; /* => next byte to write in buffer */ 00734 size_t free_in_buffer; /* # of byte spaces remaining in buffer */ 00735 00736 JMETHOD(void, init_destination, (j_compress_ptr cinfo)); 00737 JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo)); 00738 JMETHOD(void, term_destination, (j_compress_ptr cinfo)); 00739 }; 00740 00741 00742 /* Data source object for decompression */ 00743 00744 struct jpeg_source_mgr { 00745 const JOCTET * next_input_byte; /* => next byte to read from buffer */ 00746 size_t bytes_in_buffer; /* # of bytes remaining in buffer */ 00747 00748 JMETHOD(void, init_source, (j_decompress_ptr cinfo)); 00749 JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo)); 00750 JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes)); 00751 JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired)); 00752 JMETHOD(void, term_source, (j_decompress_ptr cinfo)); 00753 }; 00754 00755 00756 /* Memory manager object. 00757 * Allocates "small" objects (a few K total), "large" objects (tens of K), 00758 * and "really big" objects (virtual arrays with backing store if needed). 00759 * The memory manager does not allow individual objects to be freed; rather, 00760 * each created object is assigned to a pool, and whole pools can be freed 00761 * at once. This is faster and more convenient than remembering exactly what 00762 * to free, especially where malloc()/free() are not too speedy. 00763 * NB: alloc routines never return NULL. They exit to error_exit if not 00764 * successful. 00765 */ 00766 00767 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */ 00768 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */ 00769 #define JPOOL_NUMPOOLS 2 00770 00771 typedef struct jvirt_sarray_control * jvirt_sarray_ptr; 00772 typedef struct jvirt_barray_control * jvirt_barray_ptr; 00773 00774 00775 #ifdef C_LOSSLESS_SUPPORTED 00776 #define NEED_DARRAY 00777 #else 00778 #ifdef D_LOSSLESS_SUPPORTED 00779 #define NEED_DARRAY 00780 #endif 00781 #endif 00782 00783 struct jpeg_memory_mgr { 00784 /* Method pointers */ 00785 JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id, 00786 size_t sizeofobject)); 00787 JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id, 00788 size_t sizeofobject)); 00789 JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id, 00790 JDIMENSION samplesperrow, 00791 JDIMENSION numrows)); 00792 JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id, 00793 JDIMENSION blocksperrow, 00794 JDIMENSION numrows)); 00795 #ifdef NEED_DARRAY 00796 JMETHOD(JDIFFARRAY, alloc_darray, (j_common_ptr cinfo, int pool_id, 00797 JDIMENSION diffsperrow, 00798 JDIMENSION numrows)); 00799 #endif 00800 JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo, 00801 int pool_id, 00802 boolean pre_zero, 00803 JDIMENSION samplesperrow, 00804 JDIMENSION numrows, 00805 JDIMENSION maxaccess)); 00806 JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo, 00807 int pool_id, 00808 boolean pre_zero, 00809 JDIMENSION blocksperrow, 00810 JDIMENSION numrows, 00811 JDIMENSION maxaccess)); 00812 JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo)); 00813 JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo, 00814 jvirt_sarray_ptr ptr, 00815 JDIMENSION start_row, 00816 JDIMENSION num_rows, 00817 boolean writable)); 00818 JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo, 00819 jvirt_barray_ptr ptr, 00820 JDIMENSION start_row, 00821 JDIMENSION num_rows, 00822 boolean writable)); 00823 JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id)); 00824 JMETHOD(void, self_destruct, (j_common_ptr cinfo)); 00825 00826 /* Limit on memory allocation for this JPEG object. (Note that this is 00827 * merely advisory, not a guaranteed maximum; it only affects the space 00828 * used for virtual-array buffers.) May be changed by outer application 00829 * after creating the JPEG object. 00830 */ 00831 long max_memory_to_use; 00832 00833 /* Maximum allocation request accepted by alloc_large. */ 00834 long max_alloc_chunk; 00835 }; 00836 00837 00838 /* Routine signature for application-supplied marker processing methods. 00839 * Need not pass marker code since it is stored in cinfo->unread_marker. 00840 */ 00841 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo)); 00842 00843 00844 /* Declarations for routines called by application. 00845 * The JPP macro hides prototype parameters from compilers that can't cope. 00846 * Note JPP requires double parentheses. 00847 */ 00848 00849 #ifdef HAVE_PROTOTYPES 00850 #define JPP(arglist) arglist 00851 #else 00852 #define JPP(arglist) () 00853 #endif 00854 00855 00856 /* Short forms of external names for systems with brain-damaged linkers. 00857 * We shorten external names to be unique in the first six letters, which 00858 * is good enough for all known systems. 00859 * (If your compiler itself needs names to be unique in less than 15 00860 * characters, you are out of luck. Get a better compiler.) 00861 */ 00862 00863 /* MAKE SURE THAT ALL FUNCTIONS DECLARED GLOBAL() ARE RE-DEFINED HERE! */ 00864 00865 #ifdef NEED_SHORT_EXTERNAL_NAMES 00866 #define jcopy_block_row jcopy8_block_row 00867 #define jcopy_sample_rows jcopy8_sample_rows 00868 #define jdiv_round_up jdiv8_round_up 00869 #define jinit_1pass_quantizer jinit8_1pass_quantizer 00870 #define jinit_2pass_quantizer jinit8_2pass_quantizer 00871 #define jinit_arith_decoder jinit8_arith_decoder 00872 #define jinit_arith_encoder jinit8_arith_encoder 00873 #define jinit_c_codec jinit8_c_codec 00874 #define jinit_c_coef_controller jinit8_c_coef_controller 00875 #define jinit_c_diff_controller jinit8_c_diff_controller 00876 #define jinit_c_main_controller jinit8_c_main_controller 00877 #define jinit_c_master_control jinit8_c_master_control 00878 #define jinit_c_prep_controller jinit8_c_prep_controller 00879 #define jinit_c_scaler jinit8_c_scaler 00880 #define jinit_color_converter jinit8_color_converter 00881 #define jinit_color_deconverter jinit8_color_deconverter 00882 #define jinit_compress_master jinit8_compress_master 00883 #define jinit_d_codec jinit8_d_codec 00884 #define jinit_d_coef_controller jinit8_d_coef_controller 00885 #define jinit_d_diff_controller jinit8_d_diff_controller 00886 #define jinit_d_main_controller jinit8_d_main_controller 00887 #define jinit_d_post_controller jinit8_d_post_controller 00888 #define jinit_d_post_controller jinit8_d_post_controller 00889 #define jinit_d_scaler jinit8_d_scaler 00890 #define jinit_differencer jinit8_differencer 00891 #define jinit_downsampler jinit8_downsampler 00892 #define jinit_forward_dct jinit8_forward_dct 00893 #define jinit_input_controller jinit8_input_controller 00894 #define jinit_inverse_dct jinit8_inverse_dct 00895 #define jinit_lhuff_decoder jinit8_lhuff_decoder 00896 #define jinit_lhuff_encoder jinit8_lhuff_encoder 00897 #define jinit_lossless_c_codec jinit8_lossless_c_codec 00898 #define jinit_lossless_d_codec jinit8_lossless_d_codec 00899 #define jinit_lossy_c_codec jinit8_lossy_c_codec 00900 #define jinit_lossy_d_codec jinit8_lossy_d_codec 00901 #define jinit_marker_reader jinit8_marker_reader 00902 #define jinit_marker_writer jinit8_marker_writer 00903 #define jinit_master_decompress jinit8_master_decompress 00904 #define jinit_memory_mgr jinit8_memory_mgr 00905 #define jinit_merged_upsampler jinit8_merged_upsampler 00906 #define jinit_phuff_decoder jinit8_phuff_decoder 00907 #define jinit_phuff_encoder jinit8_phuff_encoder 00908 #define jinit_shuff_decoder jinit8_shuff_decoder 00909 #define jinit_shuff_encoder jinit8_shuff_encoder 00910 #define jinit_undifferencer jinit8_undifferencer 00911 #define jinit_upsampler jinit8_upsampler 00912 #define jpeg_CreateCompress jpeg8_CreateCompress 00913 #define jpeg_CreateDecompress jpeg8_CreateDecompress 00914 #define jpeg_abort jpeg8_abort 00915 #define jpeg_abort_compress jpeg8_abort_compress 00916 #define jpeg_abort_decompress jpeg8_abort_decompress 00917 #define jpeg_add_quant_table jpeg8_add_quant_table 00918 #define jpeg_alloc_huff_table jpeg8_alloc_huff_table 00919 #define jpeg_alloc_quant_table jpeg8_alloc_quant_table 00920 #define jpeg_calc_output_dimensions jpeg8_calc_output_dimensions 00921 #define jpeg_consume_input jpeg8_consume_input 00922 #define jpeg_copy_critical_parameters jpeg8_copy_critical_parameters 00923 #define jpeg_default_colorspace jpeg8_default_colorspace 00924 #define jpeg_destroy jpeg8_destroy 00925 #define jpeg_destroy_compress jpeg8_destroy_compress 00926 #define jpeg_destroy_decompress jpeg8_destroy_decompress 00927 #define jpeg_fdct_float jpeg8_fdct_float 00928 #define jpeg_fdct_ifast jpeg8_fdct_ifast 00929 #define jpeg_fdct_islow jpeg8_fdct_islow 00930 #define jpeg_fill_bit_buffer jpeg8_fill_bit_buffer 00931 #define jpeg_finish_compress jpeg8_finish_compress 00932 #define jpeg_finish_decompress jpeg8_finish_decompress 00933 #define jpeg_finish_output jpeg8_finish_output 00934 #define jpeg_free_large jpeg8_free_large 00935 #define jpeg_free_small jpeg8_free_small 00936 #define jpeg_gen_optimal_table jpeg8_gen_optimal_table 00937 #define jpeg_get_large jpeg8_get_large 00938 #define jpeg_get_small jpeg8_get_small 00939 #define jpeg_has_multiple_scans jpeg8_has_multiple_scans 00940 #define jpeg_huff_decode jpeg8_huff_decode 00941 #define jpeg_idct_1x1 jpeg8_idct_1x1 00942 #define jpeg_idct_2x2 jpeg8_idct_2x2 00943 #define jpeg_idct_4x4 jpeg8_idct_4x4 00944 #define jpeg_idct_float jpeg8_idct_float 00945 #define jpeg_idct_ifast jpeg8_idct_ifast 00946 #define jpeg_idct_islow jpeg8_idct_islow 00947 #define jpeg_input_complete jpeg8_input_complete 00948 #define jpeg_make_c_derived_tbl jpeg8_make_c_derived_tbl 00949 #define jpeg_make_d_derived_tbl jpeg8_make_d_derived_tbl 00950 #define jpeg_mem_available jpeg8_mem_available 00951 #define jpeg_mem_init jpeg8_mem_init 00952 #define jpeg_mem_term jpeg8_mem_term 00953 #define jpeg_new_colormap jpeg8_new_colormap 00954 #define jpeg_open_backing_store jpeg8_open_backing_store 00955 #define jpeg_quality_scaling jpeg8_quality_scaling 00956 #define jpeg_read_coefficients jpeg8_read_coefficients 00957 #define jpeg_read_header jpeg8_read_header 00958 #define jpeg_read_raw_data jpeg8_read_raw_data 00959 #define jpeg_read_scanlines jpeg8_read_scanlines 00960 #define jpeg_resync_to_restart jpeg8_resync_to_restart 00961 #define jpeg_save_markers jpeg8_save_markers 00962 #define jpeg_set_colorspace jpeg8_set_colorspace 00963 #define jpeg_set_defaults jpeg8_set_defaults 00964 #define jpeg_set_linear_quality jpeg8_set_linear_quality 00965 #define jpeg_set_marker_processor jpeg8_set_marker_processor 00966 #define jpeg_set_quality jpeg8_set_quality 00967 #define jpeg_simple_lossless jpeg8_simple_lossless 00968 #define jpeg_simple_progression jpeg8_simple_progression 00969 #define jpeg_start_compress jpeg8_start_compress 00970 #define jpeg_start_decompress jpeg8_start_decompress 00971 #define jpeg_start_output jpeg8_start_output 00972 #define jpeg_std_error jpeg8_std_error 00973 #define jpeg_stdio_dest jpeg8_stdio_dest 00974 #define jpeg_stdio_src jpeg8_stdio_src 00975 #define jpeg_suppress_tables jpeg8_suppress_tables 00976 #define jpeg_write_coefficients jpeg8_write_coefficients 00977 #define jpeg_write_m_byte jpeg8_write_m_byte 00978 #define jpeg_write_m_header jpeg8_write_m_header 00979 #define jpeg_write_marker jpeg8_write_marker 00980 #define jpeg_write_raw_data jpeg8_write_raw_data 00981 #define jpeg_write_scanlines jpeg8_write_scanlines 00982 #define jpeg_write_tables jpeg8_write_tables 00983 #define jround_up jround8_up 00984 #define jzero_far jzero8_far 00985 #endif /* NEED_SHORT_EXTERNAL_NAMES */ 00986 00987 00988 /* Default error-management setup */ 00989 EXTERN(struct jpeg_error_mgr *) jpeg_std_error 00990 JPP((struct jpeg_error_mgr * err)); 00991 00992 /* Initialization of JPEG compression objects. 00993 * jpeg_create_compress() and jpeg_create_decompress() are the exported 00994 * names that applications should call. These expand to calls on 00995 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information 00996 * passed for version mismatch checking. 00997 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx. 00998 */ 00999 #define jpeg_create_compress(cinfo) \ 01000 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \ 01001 (size_t) sizeof(struct jpeg_compress_struct)) 01002 #define jpeg_create_decompress(cinfo) \ 01003 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \ 01004 (size_t) sizeof(struct jpeg_decompress_struct)) 01005 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo, 01006 int version, size_t structsize)); 01007 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo, 01008 int version, size_t structsize)); 01009 /* Destruction of JPEG compression objects */ 01010 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo)); 01011 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo)); 01012 01013 /* Standard data source and destination managers: stdio streams. */ 01014 /* Caller is responsible for opening the file before and closing after. */ 01015 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile)); 01016 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile)); 01017 01018 /* Default parameter setup for compression */ 01019 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo)); 01020 /* Compression parameter setup aids */ 01021 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo, 01022 J_COLOR_SPACE colorspace)); 01023 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo)); 01024 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality, 01025 boolean force_baseline)); 01026 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo, 01027 int scale_factor, 01028 boolean force_baseline)); 01029 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl, 01030 const unsigned int *basic_table, 01031 int scale_factor, 01032 boolean force_baseline)); 01033 EXTERN(int) jpeg_quality_scaling JPP((int quality)); 01034 EXTERN(void) jpeg_simple_lossless JPP((j_compress_ptr cinfo, 01035 int predictor, int point_transform)); 01036 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo)); 01037 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo, 01038 boolean suppress)); 01039 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo)); 01040 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo)); 01041 01042 /* Main entry points for compression */ 01043 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo, 01044 boolean write_all_tables)); 01045 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo, 01046 JSAMPARRAY scanlines, 01047 JDIMENSION num_lines)); 01048 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo)); 01049 01050 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */ 01051 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo, 01052 JSAMPIMAGE data, 01053 JDIMENSION num_lines)); 01054 01055 /* Write a special marker. See libjpeg.doc concerning safe usage. */ 01056 EXTERN(void) jpeg_write_marker 01057 JPP((j_compress_ptr cinfo, int marker, 01058 const JOCTET * dataptr, unsigned int datalen)); 01059 /* Same, but piecemeal. */ 01060 EXTERN(void) jpeg_write_m_header 01061 JPP((j_compress_ptr cinfo, int marker, unsigned int datalen)); 01062 EXTERN(void) jpeg_write_m_byte 01063 JPP((j_compress_ptr cinfo, int val)); 01064 01065 /* Alternate compression function: just write an abbreviated table file */ 01066 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo)); 01067 01068 /* Decompression startup: read start of JPEG datastream to see what's there */ 01069 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo, 01070 boolean require_image)); 01071 /* Return value is one of: */ 01072 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */ 01073 #define JPEG_HEADER_OK 1 /* Found valid image datastream */ 01074 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */ 01075 /* If you pass require_image = TRUE (normal case), you need not check for 01076 * a TABLES_ONLY return code; an abbreviated file will cause an error exit. 01077 * JPEG_SUSPENDED is only possible if you use a data source module that can 01078 * give a suspension return (the stdio source module doesn't). 01079 */ 01080 01081 /* Main entry points for decompression */ 01082 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo)); 01083 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo, 01084 JSAMPARRAY scanlines, 01085 JDIMENSION max_lines)); 01086 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo)); 01087 01088 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */ 01089 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo, 01090 JSAMPIMAGE data, 01091 JDIMENSION max_lines)); 01092 01093 /* Additional entry points for buffered-image mode. */ 01094 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo)); 01095 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo, 01096 int scan_number)); 01097 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo)); 01098 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo)); 01099 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo)); 01100 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo)); 01101 /* Return value is one of: */ 01102 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */ 01103 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */ 01104 #define JPEG_REACHED_EOI 2 /* Reached end of image */ 01105 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */ 01106 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */ 01107 01108 /* Precalculate output dimensions for current decompression parameters. */ 01109 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo)); 01110 01111 /* Control saving of COM and APPn markers into marker_list. */ 01112 EXTERN(void) jpeg_save_markers 01113 JPP((j_decompress_ptr cinfo, int marker_code, 01114 unsigned int length_limit)); 01115 01116 /* Install a special processing method for COM or APPn markers. */ 01117 EXTERN(void) jpeg_set_marker_processor 01118 JPP((j_decompress_ptr cinfo, int marker_code, 01119 jpeg_marker_parser_method routine)); 01120 01121 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */ 01122 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo)); 01123 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo, 01124 jvirt_barray_ptr * coef_arrays)); 01125 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo, 01126 j_compress_ptr dstinfo)); 01127 01128 /* If you choose to abort compression or decompression before completing 01129 * jpeg_finish_(de)compress, then you need to clean up to release memory, 01130 * temporary files, etc. You can just call jpeg_destroy_(de)compress 01131 * if you're done with the JPEG object, but if you want to clean it up and 01132 * reuse it, call this: 01133 */ 01134 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo)); 01135 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo)); 01136 01137 /* Generic versions of jpeg_abort and jpeg_destroy that work on either 01138 * flavor of JPEG object. These may be more convenient in some places. 01139 */ 01140 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo)); 01141 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo)); 01142 01143 /* Default restart-marker-resync procedure for use by data source modules */ 01144 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo, 01145 int desired)); 01146 01147 01148 /* These marker codes are exported since applications and data source modules 01149 * are likely to want to use them. 01150 */ 01151 01152 #define JPEG_RST0 0xD0 /* RST0 marker code */ 01153 #define JPEG_EOI 0xD9 /* EOI marker code */ 01154 #define JPEG_APP0 0xE0 /* APP0 marker code */ 01155 #define JPEG_COM 0xFE /* COM marker code */ 01156 01157 01158 /* If we have a brain-damaged compiler that emits warnings (or worse, errors) 01159 * for structure definitions that are never filled in, keep it quiet by 01160 * supplying dummy definitions for the various substructures. 01161 */ 01162 01163 #ifdef INCOMPLETE_TYPES_BROKEN 01164 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */ 01165 struct jvirt_sarray_control { long dummy; }; 01166 struct jvirt_barray_control { long dummy; }; 01167 struct jpeg_comp_master { long dummy; }; 01168 struct jpeg_c_main_controller { long dummy; }; 01169 struct jpeg_c_prep_controller { long dummy; }; 01170 struct jpeg_c_coef_controller { long dummy; }; 01171 struct jpeg_marker_writer { long dummy; }; 01172 struct jpeg_color_converter { long dummy; }; 01173 struct jpeg_downsampler { long dummy; }; 01174 struct jpeg_forward_dct { long dummy; }; 01175 struct jpeg_entropy_encoder { long dummy; }; 01176 struct jpeg_decomp_master { long dummy; }; 01177 struct jpeg_d_main_controller { long dummy; }; 01178 struct jpeg_d_coef_controller { long dummy; }; 01179 struct jpeg_d_post_controller { long dummy; }; 01180 struct jpeg_input_controller { long dummy; }; 01181 struct jpeg_marker_reader { long dummy; }; 01182 struct jpeg_entropy_decoder { long dummy; }; 01183 struct jpeg_inverse_dct { long dummy; }; 01184 struct jpeg_upsampler { long dummy; }; 01185 struct jpeg_color_deconverter { long dummy; }; 01186 struct jpeg_color_quantizer { long dummy; }; 01187 #endif /* JPEG_INTERNALS */ 01188 #endif /* INCOMPLETE_TYPES_BROKEN */ 01189 01190 01191 /* 01192 * The JPEG library modules define JPEG_INTERNALS before including this file. 01193 * The internal structure declarations are read only when that is true. 01194 * Applications using the library should not include jpegint.h, but may wish 01195 * to include jerror.h. 01196 */ 01197 01198 #ifdef JPEG_INTERNALS 01199 #include "jpegint8.h" /* fetch private declarations */ 01200 #include "jerror8.h" /* fetch error codes too */ 01201 #endif 01202 01203 #endif /* JPEGLIB_H */