2 Copyright (C) 1999-2006 Id Software, Inc. and contributors.
3 For a list of contributors, see the accompanying CONTRIBUTORS file.
5 This file is part of GtkRadiant.
7 GtkRadiant is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 GtkRadiant is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GtkRadiant; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
25 * Copyright (C) 1991-1995, Thomas G. Lane.
26 * This file is part of the Independent JPEG Group's software.
27 * For conditions of distribution and use, see the accompanying README file.
29 * This file defines the application interface for the JPEG library.
30 * Most applications using the library need only include this file,
31 * and perhaps jerror.h if they want to know the exact error codes.
60 // JDC: stuff to make mac version compile
61 #define boolean qboolean
80 // TTimo: if LoadJPGBuff returns -1, *pic is the error message
81 extern int LoadJPGBuff(unsigned char *fbuffer, int bufsize, unsigned char **pic, int *width, int *height );
86 * First we include the configuration files that record how this
87 * installation of the JPEG library is set up. jconfig.h can be
88 * generated automatically for many systems. jmorecfg.h contains
89 * manual configuration options that most people need not worry about.
92 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */
93 #include "jpeg6/jconfig.h" /* widely used configuration options */
95 #include "jpeg6/jmorecfg.h" /* seldom changed options */
98 /* Version ID for the JPEG library.
99 * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
102 #define JPEG_LIB_VERSION 60 /* Version 6 */
105 /* Various constants determining the sizes of things.
106 * All of these are specified by the JPEG standard, so don't change them
107 * if you want to be compatible.
110 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */
111 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */
112 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */
113 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */
114 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */
115 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */
116 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */
117 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
118 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
119 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
120 * to handle it. We even let you do this from the jconfig.h file. However,
121 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
122 * sometimes emits noncompliant files doesn't mean you should too.
124 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */
125 #ifndef D_MAX_BLOCKS_IN_MCU
126 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */
130 /* This macro is used to declare a "method", that is, a function pointer.
131 * We want to supply prototype parameters if the compiler can cope.
132 * Note that the arglist parameter must be parenthesized!
135 #ifdef HAVE_PROTOTYPES
136 #define JMETHOD(type,methodname,arglist) type (*methodname) arglist
138 #define JMETHOD(type,methodname,arglist) type (*methodname) ()
142 /* Data structures for images (arrays of samples and of DCT coefficients).
143 * On 80x86 machines, the image arrays are too big for near pointers,
144 * but the pointer arrays can fit in near memory.
147 typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */
148 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */
149 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */
151 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */
152 typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */
153 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */
154 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */
156 typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */
159 /* Types for JPEG compression parameters and working tables. */
162 /* DCT coefficient quantization tables. */
165 /* This field directly represents the contents of a JPEG DQT marker.
166 * Note: the values are always given in zigzag order.
168 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */
169 /* This field is used only during compression. It's initialized FALSE when
170 * the table is created, and set TRUE when it's been output to the file.
171 * You could suppress output of a table by setting this to TRUE.
172 * (See jpeg_suppress_tables for an example.)
174 boolean sent_table; /* TRUE when table has been output */
178 /* Huffman coding tables. */
181 /* These two fields directly represent the contents of a JPEG DHT marker */
182 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */
183 /* length k bits; bits[0] is unused */
184 UINT8 huffval[256]; /* The symbols, in order of incr code length */
185 /* This field is used only during compression. It's initialized FALSE when
186 * the table is created, and set TRUE when it's been output to the file.
187 * You could suppress output of a table by setting this to TRUE.
188 * (See jpeg_suppress_tables for an example.)
190 boolean sent_table; /* TRUE when table has been output */
194 /* Basic info about one component (color channel). */
197 /* These values are fixed over the whole image. */
198 /* For compression, they must be supplied by parameter setup; */
199 /* for decompression, they are read from the SOF marker. */
200 int component_id; /* identifier for this component (0..255) */
201 int component_index; /* its index in SOF or cinfo->comp_info[] */
202 int h_samp_factor; /* horizontal sampling factor (1..4) */
203 int v_samp_factor; /* vertical sampling factor (1..4) */
204 int quant_tbl_no; /* quantization table selector (0..3) */
205 /* These values may vary between scans. */
206 /* For compression, they must be supplied by parameter setup; */
207 /* for decompression, they are read from the SOS marker. */
208 /* The decompressor output side may not use these variables. */
209 int dc_tbl_no; /* DC entropy table selector (0..3) */
210 int ac_tbl_no; /* AC entropy table selector (0..3) */
212 /* Remaining fields should be treated as private by applications. */
214 /* These values are computed during compression or decompression startup: */
215 /* Component's size in DCT blocks.
216 * Any dummy blocks added to complete an MCU are not counted; therefore
217 * these values do not depend on whether a scan is interleaved or not.
219 JDIMENSION width_in_blocks;
220 JDIMENSION height_in_blocks;
221 /* Size of a DCT block in samples. Always DCTSIZE for compression.
222 * For decompression this is the size of the output from one DCT block,
223 * reflecting any scaling we choose to apply during the IDCT step.
224 * Values of 1,2,4,8 are likely to be supported. Note that different
225 * components may receive different IDCT scalings.
228 /* The downsampled dimensions are the component's actual, unpadded number
229 * of samples at the main buffer (preprocessing/compression interface), thus
230 * downsampled_width = ceil(image_width * Hi/Hmax)
231 * and similarly for height. For decompression, IDCT scaling is included, so
232 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
234 JDIMENSION downsampled_width; /* actual width in samples */
235 JDIMENSION downsampled_height; /* actual height in samples */
236 /* This flag is used only for decompression. In cases where some of the
237 * components will be ignored (eg grayscale output from YCbCr image),
238 * we can skip most computations for the unused components.
240 boolean component_needed; /* do we need the value of this component? */
242 /* These values are computed before starting a scan of the component. */
243 /* The decompressor output side may not use these variables. */
244 int MCU_width; /* number of blocks per MCU, horizontally */
245 int MCU_height; /* number of blocks per MCU, vertically */
246 int MCU_blocks; /* MCU_width * MCU_height */
247 int MCU_sample_width; /* MCU width in samples, MCU_width*DCT_scaled_size */
248 int last_col_width; /* # of non-dummy blocks across in last MCU */
249 int last_row_height; /* # of non-dummy blocks down in last MCU */
251 /* Saved quantization table for component; NULL if none yet saved.
252 * See jdinput.c comments about the need for this information.
253 * This field is not currently used by the compressor.
255 JQUANT_TBL * quant_table;
257 /* Private per-component storage for DCT or IDCT subsystem. */
259 } jpeg_component_info;
262 /* The script for encoding a multiple-scan file is an array of these: */
265 int comps_in_scan; /* number of components encoded in this scan */
266 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
267 int Ss, Se; /* progressive JPEG spectral selection parms */
268 int Ah, Al; /* progressive JPEG successive approx. parms */
272 /* Known color spaces. */
275 JCS_UNKNOWN, /* error/unspecified */
276 JCS_GRAYSCALE, /* monochrome */
277 JCS_RGB, /* red/green/blue */
278 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */
279 JCS_CMYK, /* C/M/Y/K */
280 JCS_YCCK /* Y/Cb/Cr/K */
283 /* DCT/IDCT algorithm options. */
286 JDCT_ISLOW, /* slow but accurate integer algorithm */
287 JDCT_IFAST, /* faster, less accurate integer method */
288 JDCT_FLOAT /* floating-point: accurate, fast on fast HW */
291 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */
292 #define JDCT_DEFAULT JDCT_ISLOW
294 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */
295 #define JDCT_FASTEST JDCT_IFAST
298 /* Dithering options for decompression. */
301 JDITHER_NONE, /* no dithering */
302 JDITHER_ORDERED, /* simple ordered dither */
303 JDITHER_FS /* Floyd-Steinberg error diffusion dither */
307 /* Common fields between JPEG compression and decompression master structs. */
309 #define jpeg_common_fields \
310 struct jpeg_error_mgr * err; /* Error handler module */\
311 struct jpeg_memory_mgr * mem; /* Memory manager module */\
312 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
313 boolean is_decompressor; /* so common code can tell which is which */\
314 int global_state /* for checking call sequence validity */
316 /* Routines that are to be used by both halves of the library are declared
317 * to receive a pointer to this structure. There are no actual instances of
318 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
320 struct jpeg_common_struct {
321 jpeg_common_fields; /* Fields common to both master struct types */
322 /* Additional fields follow in an actual jpeg_compress_struct or
323 * jpeg_decompress_struct. All three structs must agree on these
324 * initial fields! (This would be a lot cleaner in C++.)
328 typedef struct jpeg_common_struct * j_common_ptr;
329 typedef struct jpeg_compress_struct * j_compress_ptr;
330 typedef struct jpeg_decompress_struct * j_decompress_ptr;
333 /* Master record for a compression instance */
335 struct jpeg_compress_struct {
336 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */
338 /* Destination for compressed data */
339 struct jpeg_destination_mgr * dest;
341 /* Description of source image --- these fields must be filled in by
342 * outer application before starting compression. in_color_space must
343 * be correct before you can even call jpeg_set_defaults().
346 JDIMENSION image_width; /* input image width */
347 JDIMENSION image_height; /* input image height */
348 int input_components; /* # of color components in input image */
349 J_COLOR_SPACE in_color_space; /* colorspace of input image */
351 double input_gamma; /* image gamma of input image */
353 /* Compression parameters --- these fields must be set before calling
354 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to
355 * initialize everything to reasonable defaults, then changing anything
356 * the application specifically wants to change. That way you won't get
357 * burnt when new parameters are added. Also note that there are several
358 * helper routines to simplify changing parameters.
361 int data_precision; /* bits of precision in image data */
363 int num_components; /* # of color components in JPEG image */
364 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
366 jpeg_component_info * comp_info;
367 /* comp_info[i] describes component that appears i'th in SOF */
369 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
370 /* ptrs to coefficient quantization tables, or NULL if not defined */
372 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
373 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
374 /* ptrs to Huffman coding tables, or NULL if not defined */
376 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
377 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
378 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
380 int num_scans; /* # of entries in scan_info array */
381 const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
382 /* The default value of scan_info is NULL, which causes a single-scan
383 * sequential JPEG file to be emitted. To create a multi-scan file,
384 * set num_scans and scan_info to point to an array of scan definitions.
387 boolean raw_data_in; /* TRUE=caller supplies downsampled data */
388 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
389 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */
390 boolean CCIR601_sampling; /* TRUE=first samples are cosited */
391 int smoothing_factor; /* 1..100, or 0 for no input smoothing */
392 J_DCT_METHOD dct_method; /* DCT algorithm selector */
394 /* The restart interval can be specified in absolute MCUs by setting
395 * restart_interval, or in MCU rows by setting restart_in_rows
396 * (in which case the correct restart_interval will be figured
399 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
400 int restart_in_rows; /* if > 0, MCU rows per restart interval */
402 /* Parameters controlling emission of special markers. */
404 boolean write_JFIF_header; /* should a JFIF marker be written? */
405 /* These three values are not used by the JPEG code, merely copied */
406 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */
407 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */
408 /* ratio is defined by X_density/Y_density even when density_unit=0. */
409 UINT8 density_unit; /* JFIF code for pixel size units */
410 UINT16 X_density; /* Horizontal pixel density */
411 UINT16 Y_density; /* Vertical pixel density */
412 boolean write_Adobe_marker; /* should an Adobe marker be written? */
414 /* State variable: index of next scanline to be written to
415 * jpeg_write_scanlines(). Application may use this to control its
416 * processing loop, e.g., "while (next_scanline < image_height)".
419 JDIMENSION next_scanline; /* 0 .. image_height-1 */
421 /* Remaining fields are known throughout compressor, but generally
422 * should not be touched by a surrounding application.
426 * These fields are computed during compression startup
428 boolean progressive_mode; /* TRUE if scan script uses progressive mode */
429 int max_h_samp_factor; /* largest h_samp_factor */
430 int max_v_samp_factor; /* largest v_samp_factor */
432 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */
433 /* The coefficient controller receives data in units of MCU rows as defined
434 * for fully interleaved scans (whether the JPEG file is interleaved or not).
435 * There are v_samp_factor * DCTSIZE sample rows of each component in an
436 * "iMCU" (interleaved MCU) row.
440 * These fields are valid during any one scan.
441 * They describe the components and MCUs actually appearing in the scan.
443 int comps_in_scan; /* # of JPEG components in this scan */
444 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
445 /* *cur_comp_info[i] describes component that appears i'th in SOS */
447 JDIMENSION MCUs_per_row; /* # of MCUs across the image */
448 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
450 int blocks_in_MCU; /* # of DCT blocks per MCU */
451 int MCU_membership[C_MAX_BLOCKS_IN_MCU];
452 /* MCU_membership[i] is index in cur_comp_info of component owning */
453 /* i'th block in an MCU */
455 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
458 * Links to compression subobjects (methods and private variables of modules)
460 struct jpeg_comp_master * master;
461 struct jpeg_c_main_controller * main;
462 struct jpeg_c_prep_controller * prep;
463 struct jpeg_c_coef_controller * coef;
464 struct jpeg_marker_writer * marker;
465 struct jpeg_color_converter * cconvert;
466 struct jpeg_downsampler * downsample;
467 struct jpeg_forward_dct * fdct;
468 struct jpeg_entropy_encoder * entropy;
472 /* Master record for a decompression instance */
474 struct jpeg_decompress_struct {
475 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */
477 /* Source of compressed data */
478 struct jpeg_source_mgr * src;
480 /* Basic description of image --- filled in by jpeg_read_header(). */
481 /* Application may inspect these values to decide how to process image. */
483 JDIMENSION image_width; /* nominal image width (from SOF marker) */
484 JDIMENSION image_height; /* nominal image height */
485 int num_components; /* # of color components in JPEG image */
486 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
488 /* Decompression processing parameters --- these fields must be set before
489 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes
490 * them to default values.
493 J_COLOR_SPACE out_color_space; /* colorspace for output */
495 unsigned int scale_num, scale_denom; /* fraction by which to scale image */
497 double output_gamma; /* image gamma wanted in output */
499 boolean buffered_image; /* TRUE=multiple output passes */
500 boolean raw_data_out; /* TRUE=downsampled data wanted */
502 J_DCT_METHOD dct_method; /* IDCT algorithm selector */
503 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */
504 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */
506 boolean quantize_colors; /* TRUE=colormapped output wanted */
507 /* the following are ignored if not quantize_colors: */
508 J_DITHER_MODE dither_mode; /* type of color dithering to use */
509 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */
510 int desired_number_of_colors; /* max # colors to use in created colormap */
511 /* these are significant only in buffered-image mode: */
512 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */
513 boolean enable_external_quant;/* enable future use of external colormap */
514 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */
516 /* Description of actual output image that will be returned to application.
517 * These fields are computed by jpeg_start_decompress().
518 * You can also use jpeg_calc_output_dimensions() to determine these values
519 * in advance of calling jpeg_start_decompress().
522 JDIMENSION output_width; /* scaled image width */
523 JDIMENSION output_height; /* scaled image height */
524 int out_color_components; /* # of color components in out_color_space */
525 int output_components; /* # of color components returned */
526 /* output_components is 1 (a colormap index) when quantizing colors;
527 * otherwise it equals out_color_components.
529 int rec_outbuf_height; /* min recommended height of scanline buffer */
530 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
531 * high, space and time will be wasted due to unnecessary data copying.
532 * Usually rec_outbuf_height will be 1 or 2, at most 4.
535 /* When quantizing colors, the output colormap is described by these fields.
536 * The application can supply a colormap by setting colormap non-NULL before
537 * calling jpeg_start_decompress; otherwise a colormap is created during
538 * jpeg_start_decompress or jpeg_start_output.
539 * The map has out_color_components rows and actual_number_of_colors columns.
541 int actual_number_of_colors; /* number of entries in use */
542 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */
544 /* State variables: these variables indicate the progress of decompression.
545 * The application may examine these but must not modify them.
548 /* Row index of next scanline to be read from jpeg_read_scanlines().
549 * Application may use this to control its processing loop, e.g.,
550 * "while (output_scanline < output_height)".
552 JDIMENSION output_scanline; /* 0 .. output_height-1 */
554 /* Current input scan number and number of iMCU rows completed in scan.
555 * These indicate the progress of the decompressor input side.
557 int input_scan_number; /* Number of SOS markers seen so far */
558 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */
560 /* The "output scan number" is the notional scan being displayed by the
561 * output side. The decompressor will not allow output scan/row number
562 * to get ahead of input scan/row, but it can fall arbitrarily far behind.
564 int output_scan_number; /* Nominal scan number being displayed */
565 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */
567 /* Current progression status. coef_bits[c][i] indicates the precision
568 * with which component c's DCT coefficient i (in zigzag order) is known.
569 * It is -1 when no data has yet been received, otherwise it is the point
570 * transform (shift) value for the most recent scan of the coefficient
571 * (thus, 0 at completion of the progression).
572 * This pointer is NULL when reading a non-progressive file.
574 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */
576 /* Internal JPEG parameters --- the application usually need not look at
577 * these fields. Note that the decompressor output side may not use
578 * any parameters that can change between scans.
581 /* Quantization and Huffman tables are carried forward across input
582 * datastreams when processing abbreviated JPEG datastreams.
585 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
586 /* ptrs to coefficient quantization tables, or NULL if not defined */
588 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
589 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
590 /* ptrs to Huffman coding tables, or NULL if not defined */
592 /* These parameters are never carried across datastreams, since they
593 * are given in SOF/SOS markers or defined to be reset by SOI.
596 int data_precision; /* bits of precision in image data */
598 jpeg_component_info * comp_info;
599 /* comp_info[i] describes component that appears i'th in SOF */
601 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */
602 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
604 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
605 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
606 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
608 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
610 /* These fields record data obtained from optional markers recognized by
613 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */
614 /* Data copied from JFIF marker: */
615 UINT8 density_unit; /* JFIF code for pixel size units */
616 UINT16 X_density; /* Horizontal pixel density */
617 UINT16 Y_density; /* Vertical pixel density */
618 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */
619 UINT8 Adobe_transform; /* Color transform code from Adobe marker */
621 boolean CCIR601_sampling; /* TRUE=first samples are cosited */
623 /* Remaining fields are known throughout decompressor, but generally
624 * should not be touched by a surrounding application.
628 * These fields are computed during decompression startup
630 int max_h_samp_factor; /* largest h_samp_factor */
631 int max_v_samp_factor; /* largest v_samp_factor */
633 int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */
635 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */
636 /* The coefficient controller's input and output progress is measured in
637 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows
638 * in fully interleaved JPEG scans, but are used whether the scan is
639 * interleaved or not. We define an iMCU row as v_samp_factor DCT block
640 * rows of each component. Therefore, the IDCT output contains
641 * v_samp_factor*DCT_scaled_size sample rows of a component per iMCU row.
644 JSAMPLE * sample_range_limit; /* table for fast range-limiting */
647 * These fields are valid during any one scan.
648 * They describe the components and MCUs actually appearing in the scan.
649 * Note that the decompressor output side must not use these fields.
651 int comps_in_scan; /* # of JPEG components in this scan */
652 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
653 /* *cur_comp_info[i] describes component that appears i'th in SOS */
655 JDIMENSION MCUs_per_row; /* # of MCUs across the image */
656 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
658 int blocks_in_MCU; /* # of DCT blocks per MCU */
659 int MCU_membership[D_MAX_BLOCKS_IN_MCU];
660 /* MCU_membership[i] is index in cur_comp_info of component owning */
661 /* i'th block in an MCU */
663 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
665 /* This field is shared between entropy decoder and marker parser.
666 * It is either zero or the code of a JPEG marker that has been
667 * read from the data source, but has not yet been processed.
672 * Links to decompression subobjects (methods, private variables of modules)
674 struct jpeg_decomp_master * master;
675 struct jpeg_d_main_controller * main;
676 struct jpeg_d_coef_controller * coef;
677 struct jpeg_d_post_controller * post;
678 struct jpeg_input_controller * inputctl;
679 struct jpeg_marker_reader * marker;
680 struct jpeg_entropy_decoder * entropy;
681 struct jpeg_inverse_dct * idct;
682 struct jpeg_upsampler * upsample;
683 struct jpeg_color_deconverter * cconvert;
684 struct jpeg_color_quantizer * cquantize;
688 /* "Object" declarations for JPEG modules that may be supplied or called
689 * directly by the surrounding application.
690 * As with all objects in the JPEG library, these structs only define the
691 * publicly visible methods and state variables of a module. Additional
692 * private fields may exist after the public ones.
696 /* Error handler object */
698 struct jpeg_error_mgr {
699 /* Error exit handler: does not return to caller */
700 JMETHOD(void, error_exit, (j_common_ptr cinfo));
701 /* Conditionally emit a trace or warning message */
702 JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
703 /* Routine that actually outputs a trace or error message */
704 JMETHOD(void, output_message, (j_common_ptr cinfo));
705 /* Format a message string for the most recent JPEG error or message */
706 JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
707 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */
708 /* Reset error state variables at start of a new image */
709 JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
711 /* The message ID code and any parameters are saved here.
712 * A message can have one string parameter or up to 8 int parameters.
715 #define JMSG_STR_PARM_MAX 80
718 char s[JMSG_STR_PARM_MAX];
721 /* Standard state variables for error facility */
723 int trace_level; /* max msg_level that will be displayed */
725 /* For recoverable corrupt-data errors, we emit a warning message,
726 * but keep going unless emit_message chooses to abort. emit_message
727 * should count warnings in num_warnings. The surrounding application
728 * can check for bad data by seeing if num_warnings is nonzero at the
731 long num_warnings; /* number of corrupt-data warnings */
733 /* These fields point to the table(s) of error message strings.
734 * An application can change the table pointer to switch to a different
735 * message list (typically, to change the language in which errors are
736 * reported). Some applications may wish to add additional error codes
737 * that will be handled by the JPEG library error mechanism; the second
738 * table pointer is used for this purpose.
740 * First table includes all errors generated by JPEG library itself.
741 * Error code 0 is reserved for a "no such error string" message.
743 const char * const * jpeg_message_table; /* Library errors */
744 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */
745 /* Second table can be added by application (see cjpeg/djpeg for example).
746 * It contains strings numbered first_addon_message..last_addon_message.
748 const char * const * addon_message_table; /* Non-library errors */
749 int first_addon_message; /* code for first string in addon table */
750 int last_addon_message; /* code for last string in addon table */
754 /* Progress monitor object */
756 struct jpeg_progress_mgr {
757 JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
759 long pass_counter; /* work units completed in this pass */
760 long pass_limit; /* total number of work units in this pass */
761 int completed_passes; /* passes completed so far */
762 int total_passes; /* total number of passes expected */
766 /* Data destination object for compression */
768 struct jpeg_destination_mgr {
769 JOCTET * next_output_byte; /* => next byte to write in buffer */
770 size_t free_in_buffer; /* # of byte spaces remaining in buffer */
772 JMETHOD(void, init_destination, (j_compress_ptr cinfo));
773 JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
774 JMETHOD(void, term_destination, (j_compress_ptr cinfo));
778 /* Data source object for decompression */
780 struct jpeg_source_mgr {
781 const JOCTET * next_input_byte; /* => next byte to read from buffer */
782 size_t bytes_in_buffer; /* # of bytes remaining in buffer */
784 JMETHOD(void, init_source, (j_decompress_ptr cinfo));
785 JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
786 JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
787 JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
788 JMETHOD(void, term_source, (j_decompress_ptr cinfo));
792 /* Memory manager object.
793 * Allocates "small" objects (a few K total), "large" objects (tens of K),
794 * and "really big" objects (virtual arrays with backing store if needed).
795 * The memory manager does not allow individual objects to be freed; rather,
796 * each created object is assigned to a pool, and whole pools can be freed
797 * at once. This is faster and more convenient than remembering exactly what
798 * to free, especially where malloc()/free() are not too speedy.
799 * NB: alloc routines never return NULL. They exit to error_exit if not
803 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */
804 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */
805 #define JPOOL_NUMPOOLS 2
807 typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
808 typedef struct jvirt_barray_control * jvirt_barray_ptr;
811 struct jpeg_memory_mgr {
812 /* Method pointers */
813 JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
814 size_t sizeofobject));
815 JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
816 size_t sizeofobject));
817 JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
818 JDIMENSION samplesperrow,
819 JDIMENSION numrows));
820 JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
821 JDIMENSION blocksperrow,
822 JDIMENSION numrows));
823 JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
826 JDIMENSION samplesperrow,
828 JDIMENSION maxaccess));
829 JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
832 JDIMENSION blocksperrow,
834 JDIMENSION maxaccess));
835 JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
836 JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
837 jvirt_sarray_ptr ptr,
838 JDIMENSION start_row,
841 JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
842 jvirt_barray_ptr ptr,
843 JDIMENSION start_row,
846 JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
847 JMETHOD(void, self_destruct, (j_common_ptr cinfo));
849 /* Limit on memory allocation for this JPEG object. (Note that this is
850 * merely advisory, not a guaranteed maximum; it only affects the space
851 * used for virtual-array buffers.) May be changed by outer application
852 * after creating the JPEG object.
854 long max_memory_to_use;
858 /* Routine signature for application-supplied marker processing methods.
859 * Need not pass marker code since it is stored in cinfo->unread_marker.
861 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
864 /* Declarations for routines called by application.
865 * The JPP macro hides prototype parameters from compilers that can't cope.
866 * Note JPP requires double parentheses.
869 #ifdef HAVE_PROTOTYPES
870 #define JPP(arglist) arglist
872 #define JPP(arglist) ()
876 /* Short forms of external names for systems with brain-damaged linkers.
877 * We shorten external names to be unique in the first six letters, which
878 * is good enough for all known systems.
879 * (If your compiler itself needs names to be unique in less than 15
880 * characters, you are out of luck. Get a better compiler.)
883 #ifdef NEED_SHORT_EXTERNAL_NAMES
884 #define jpeg_std_error jStdError
885 #define jpeg_create_compress jCreaCompress
886 #define jpeg_create_decompress jCreaDecompress
887 #define jpeg_destroy_compress jDestCompress
888 #define jpeg_destroy_decompress jDestDecompress
889 #define jpeg_stdio_dest jStdDest
890 #define jpeg_stdio_src jStdSrc
891 #define jpeg_set_defaults jSetDefaults
892 #define jpeg_set_colorspace jSetColorspace
893 #define jpeg_default_colorspace jDefColorspace
894 #define jpeg_set_quality jSetQuality
895 #define jpeg_set_linear_quality jSetLQuality
896 #define jpeg_add_quant_table jAddQuantTable
897 #define jpeg_quality_scaling jQualityScaling
898 #define jpeg_simple_progression jSimProgress
899 #define jpeg_suppress_tables jSuppressTables
900 #define jpeg_alloc_quant_table jAlcQTable
901 #define jpeg_alloc_huff_table jAlcHTable
902 #define jpeg_start_compress jStrtCompress
903 #define jpeg_write_scanlines jWrtScanlines
904 #define jpeg_finish_compress jFinCompress
905 #define jpeg_write_raw_data jWrtRawData
906 #define jpeg_write_marker jWrtMarker
907 #define jpeg_write_tables jWrtTables
908 #define jpeg_read_header jReadHeader
909 #define jpeg_start_decompress jStrtDecompress
910 #define jpeg_read_scanlines jReadScanlines
911 #define jpeg_finish_decompress jFinDecompress
912 #define jpeg_read_raw_data jReadRawData
913 #define jpeg_has_multiple_scans jHasMultScn
914 #define jpeg_start_output jStrtOutput
915 #define jpeg_finish_output jFinOutput
916 #define jpeg_input_complete jInComplete
917 #define jpeg_new_colormap jNewCMap
918 #define jpeg_consume_input jConsumeInput
919 #define jpeg_calc_output_dimensions jCalcDimensions
920 #define jpeg_set_marker_processor jSetMarker
921 #define jpeg_read_coefficients jReadCoefs
922 #define jpeg_write_coefficients jWrtCoefs
923 #define jpeg_copy_critical_parameters jCopyCrit
924 #define jpeg_abort_compress jAbrtCompress
925 #define jpeg_abort_decompress jAbrtDecompress
926 #define jpeg_abort jAbort
927 #define jpeg_destroy jDestroy
928 #define jpeg_resync_to_restart jResyncRestart
929 #endif /* NEED_SHORT_EXTERNAL_NAMES */
932 /* Default error-management setup */
933 EXTERN struct jpeg_error_mgr *jpeg_std_error JPP((struct jpeg_error_mgr *err));
935 /* Initialization and destruction of JPEG compression objects */
936 /* NB: you must set up the error-manager BEFORE calling jpeg_create_xxx */
937 EXTERN void jpeg_create_compress JPP((j_compress_ptr cinfo));
938 EXTERN void jpeg_create_decompress JPP((j_decompress_ptr cinfo));
939 EXTERN void jpeg_destroy_compress JPP((j_compress_ptr cinfo));
940 EXTERN void jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
942 /* Standard data source and destination managers: stdio streams. */
943 /* Caller is responsible for opening the file before and closing after. */
944 EXTERN void jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
945 EXTERN void jpeg_stdio_src JPP((j_decompress_ptr cinfo, unsigned char *infile, int bufsize));
947 /* Default parameter setup for compression */
948 EXTERN void jpeg_set_defaults JPP((j_compress_ptr cinfo));
949 /* Compression parameter setup aids */
950 EXTERN void jpeg_set_colorspace JPP((j_compress_ptr cinfo,
951 J_COLOR_SPACE colorspace));
952 EXTERN void jpeg_default_colorspace JPP((j_compress_ptr cinfo));
953 EXTERN void jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
954 boolean force_baseline));
955 EXTERN void jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
957 boolean force_baseline));
958 EXTERN void jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
959 const unsigned int *basic_table,
961 boolean force_baseline));
962 EXTERN int jpeg_quality_scaling JPP((int quality));
963 EXTERN void jpeg_simple_progression JPP((j_compress_ptr cinfo));
964 EXTERN void jpeg_suppress_tables JPP((j_compress_ptr cinfo,
966 EXTERN JQUANT_TBL * jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
967 EXTERN JHUFF_TBL * jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
969 /* Main entry points for compression */
970 EXTERN void jpeg_start_compress JPP((j_compress_ptr cinfo,
971 boolean write_all_tables));
972 EXTERN JDIMENSION jpeg_write_scanlines JPP((j_compress_ptr cinfo,
973 JSAMPARRAY scanlines,
974 JDIMENSION num_lines));
975 EXTERN void jpeg_finish_compress JPP((j_compress_ptr cinfo));
977 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
978 EXTERN JDIMENSION jpeg_write_raw_data JPP((j_compress_ptr cinfo,
980 JDIMENSION num_lines));
982 /* Write a special marker. See libjpeg.doc concerning safe usage. */
983 EXTERN void jpeg_write_marker JPP((j_compress_ptr cinfo, int marker,
984 const JOCTET *dataptr, unsigned int datalen));
986 /* Alternate compression function: just write an abbreviated table file */
987 EXTERN void jpeg_write_tables JPP((j_compress_ptr cinfo));
989 /* Decompression startup: read start of JPEG datastream to see what's there */
990 EXTERN int jpeg_read_header JPP((j_decompress_ptr cinfo,
991 boolean require_image));
992 /* Return value is one of: */
993 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */
994 #define JPEG_HEADER_OK 1 /* Found valid image datastream */
995 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */
996 /* If you pass require_image = TRUE (normal case), you need not check for
997 * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
998 * JPEG_SUSPENDED is only possible if you use a data source module that can
999 * give a suspension return (the stdio source module doesn't).
1002 /* Main entry points for decompression */
1003 EXTERN boolean jpeg_start_decompress JPP((j_decompress_ptr cinfo));
1004 EXTERN JDIMENSION jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
1005 JSAMPARRAY scanlines,
1006 JDIMENSION max_lines));
1007 EXTERN boolean jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
1009 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
1010 EXTERN JDIMENSION jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
1012 JDIMENSION max_lines));
1014 /* Additional entry points for buffered-image mode. */
1015 EXTERN boolean jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
1016 EXTERN boolean jpeg_start_output JPP((j_decompress_ptr cinfo,
1018 EXTERN boolean jpeg_finish_output JPP((j_decompress_ptr cinfo));
1019 EXTERN boolean jpeg_input_complete JPP((j_decompress_ptr cinfo));
1020 EXTERN void jpeg_new_colormap JPP((j_decompress_ptr cinfo));
1021 EXTERN int jpeg_consume_input JPP((j_decompress_ptr cinfo));
1022 /* Return value is one of: */
1023 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */
1024 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */
1025 #define JPEG_REACHED_EOI 2 /* Reached end of image */
1026 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */
1027 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */
1029 /* Precalculate output dimensions for current decompression parameters. */
1030 EXTERN void jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
1032 /* Install a special processing method for COM or APPn markers. */
1033 EXTERN void jpeg_set_marker_processor JPP((j_decompress_ptr cinfo,
1035 jpeg_marker_parser_method routine));
1037 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
1038 EXTERN jvirt_barray_ptr * jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
1039 EXTERN void jpeg_write_coefficients JPP((j_compress_ptr cinfo,
1040 jvirt_barray_ptr * coef_arrays));
1041 EXTERN void jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
1042 j_compress_ptr dstinfo));
1044 /* If you choose to abort compression or decompression before completing
1045 * jpeg_finish_(de)compress, then you need to clean up to release memory,
1046 * temporary files, etc. You can just call jpeg_destroy_(de)compress
1047 * if you're done with the JPEG object, but if you want to clean it up and
1048 * reuse it, call this:
1050 EXTERN void jpeg_abort_compress JPP((j_compress_ptr cinfo));
1051 EXTERN void jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
1053 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
1054 * flavor of JPEG object. These may be more convenient in some places.
1056 EXTERN void jpeg_abort JPP((j_common_ptr cinfo));
1057 EXTERN void jpeg_destroy JPP((j_common_ptr cinfo));
1059 /* Default restart-marker-resync procedure for use by data source modules */
1060 EXTERN boolean jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
1064 /* These marker codes are exported since applications and data source modules
1065 * are likely to want to use them.
1068 #define JPEG_RST0 0xD0 /* RST0 marker code */
1069 #define JPEG_EOI 0xD9 /* EOI marker code */
1070 #define JPEG_APP0 0xE0 /* APP0 marker code */
1071 #define JPEG_COM 0xFE /* COM marker code */
1074 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
1075 * for structure definitions that are never filled in, keep it quiet by
1076 * supplying dummy definitions for the various substructures.
1079 #ifdef INCOMPLETE_TYPES_BROKEN
1080 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */
1081 struct jvirt_sarray_control { long dummy; };
1082 struct jvirt_barray_control { long dummy; };
1083 struct jpeg_comp_master { long dummy; };
1084 struct jpeg_c_main_controller { long dummy; };
1085 struct jpeg_c_prep_controller { long dummy; };
1086 struct jpeg_c_coef_controller { long dummy; };
1087 struct jpeg_marker_writer { long dummy; };
1088 struct jpeg_color_converter { long dummy; };
1089 struct jpeg_downsampler { long dummy; };
1090 struct jpeg_forward_dct { long dummy; };
1091 struct jpeg_entropy_encoder { long dummy; };
1092 struct jpeg_decomp_master { long dummy; };
1093 struct jpeg_d_main_controller { long dummy; };
1094 struct jpeg_d_coef_controller { long dummy; };
1095 struct jpeg_d_post_controller { long dummy; };
1096 struct jpeg_input_controller { long dummy; };
1097 struct jpeg_marker_reader { long dummy; };
1098 struct jpeg_entropy_decoder { long dummy; };
1099 struct jpeg_inverse_dct { long dummy; };
1100 struct jpeg_upsampler { long dummy; };
1101 struct jpeg_color_deconverter { long dummy; };
1102 struct jpeg_color_quantizer { long dummy; };
1103 #endif /* JPEG_INTERNALS */
1104 #endif /* INCOMPLETE_TYPES_BROKEN */
1108 * The JPEG library modules define JPEG_INTERNALS before including this file.
1109 * The internal structure declarations are read only when that is true.
1110 * Applications using the library should not include jpegint.h, but may wish
1111 * to include jerror.h.
1114 #ifdef JPEG_INTERNALS
1115 #include "jpegint.h" /* fetch private declarations */
1116 #include "jerror.h" /* fetch error codes too */
1123 #endif /* JPEGLIB_H */