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jpeglib.h (46205B)
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1 /*
2 * jpeglib.h
3 *
4 * Copyright (C) 1991-1998, Thomas G. Lane.
5 * This file is part of the Independent JPEG Group's software.
6 * For conditions of distribution and use, see the accompanying README file.
7 *
8 * This file defines the application interface for the JPEG library.
9 * Most applications using the library need only include this file,
10 * and perhaps jerror.h if they want to know the exact error codes.
11 */
12
13 #ifndef JPEGLIB_H
14 #define JPEGLIB_H
15
16 /*
17 * First we include the configuration files that record how this
18 * installation of the JPEG library is set up. jconfig.h can be
19 * generated automatically for many systems. jmorecfg.h contains
20 * manual configuration options that most people need not worry about.
21 */
22
23 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */
24 #include "jconfig.h" /* widely used configuration options */
25 #endif
26 #include "jmorecfg.h" /* seldom changed options */
27
28
29 /* Version ID for the JPEG library.
30 * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
31 */
32
33 #define JPEG_LIB_VERSION 62 /* Version 6b */
34
35
36 /* Various constants determining the sizes of things.
37 * All of these are specified by the JPEG standard, so don't change them
38 * if you want to be compatible.
39 */
40
41 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */
42 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */
43 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */
44 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */
45 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */
46 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */
47 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */
48 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
49 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
50 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
51 * to handle it. We even let you do this from the jconfig.h file. However,
52 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
53 * sometimes emits noncompliant files doesn't mean you should too.
54 */
55 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */
56 #ifndef D_MAX_BLOCKS_IN_MCU
57 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */
58 #endif
59
60
61 /* Data structures for images (arrays of samples and of DCT coefficients).
62 * On 80x86 machines, the image arrays are too big for near pointers,
63 * but the pointer arrays can fit in near memory.
64 */
65
66 typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */
67 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */
68 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */
69
70 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */
71 typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */
72 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */
73 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */
74
75 typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */
76
77
78 /* Types for JPEG compression parameters and working tables. */
79
80
81 /* DCT coefficient quantization tables. */
82
83 typedef struct {
84 /* This array gives the coefficient quantizers in natural array order
85 * (not the zigzag order in which they are stored in a JPEG DQT marker).
86 * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
87 */
88 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */
89 /* This field is used only during compression. It's initialized FALSE when
90 * the table is created, and set TRUE when it's been output to the file.
91 * You could suppress output of a table by setting this to TRUE.
92 * (See jpeg_suppress_tables for an example.)
93 */
94 boolean sent_table; /* TRUE when table has been output */
95 } JQUANT_TBL;
96
97
98 /* Huffman coding tables. */
99
100 typedef struct {
101 /* These two fields directly represent the contents of a JPEG DHT marker */
102 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */
103 /* length k bits; bits[0] is unused */
104 UINT8 huffval[256]; /* The symbols, in order of incr code length */
105 /* This field is used only during compression. It's initialized FALSE when
106 * the table is created, and set TRUE when it's been output to the file.
107 * You could suppress output of a table by setting this to TRUE.
108 * (See jpeg_suppress_tables for an example.)
109 */
110 boolean sent_table; /* TRUE when table has been output */
111 } JHUFF_TBL;
112
113
114 /* Basic info about one component (color channel). */
115
116 typedef struct {
117 /* These values are fixed over the whole image. */
118 /* For compression, they must be supplied by parameter setup; */
119 /* for decompression, they are read from the SOF marker. */
120 int component_id; /* identifier for this component (0..255) */
121 int component_index; /* its index in SOF or cinfo->comp_info[] */
122 int h_samp_factor; /* horizontal sampling factor (1..4) */
123 int v_samp_factor; /* vertical sampling factor (1..4) */
124 int quant_tbl_no; /* quantization table selector (0..3) */
125 /* These values may vary between scans. */
126 /* For compression, they must be supplied by parameter setup; */
127 /* for decompression, they are read from the SOS marker. */
128 /* The decompressor output side may not use these variables. */
129 int dc_tbl_no; /* DC entropy table selector (0..3) */
130 int ac_tbl_no; /* AC entropy table selector (0..3) */
131
132 /* Remaining fields should be treated as private by applications. */
133
134 /* These values are computed during compression or decompression startup: */
135 /* Component's size in DCT blocks.
136 * Any dummy blocks added to complete an MCU are not counted; therefore
137 * these values do not depend on whether a scan is interleaved or not.
138 */
139 JDIMENSION width_in_blocks;
140 JDIMENSION height_in_blocks;
141 /* Size of a DCT block in samples. Always DCTSIZE for compression.
142 * For decompression this is the size of the output from one DCT block,
143 * reflecting any scaling we choose to apply during the IDCT step.
144 * Values of 1,2,4,8 are likely to be supported. Note that different
145 * components may receive different IDCT scalings.
146 */
147 int DCT_scaled_size;
148 /* The downsampled dimensions are the component's actual, unpadded number
149 * of samples at the main buffer (preprocessing/compression interface), thus
150 * downsampled_width = ceil(image_width * Hi/Hmax)
151 * and similarly for height. For decompression, IDCT scaling is included, so
152 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
153 */
154 JDIMENSION downsampled_width; /* actual width in samples */
155 JDIMENSION downsampled_height; /* actual height in samples */
156 /* This flag is used only for decompression. In cases where some of the
157 * components will be ignored (eg grayscale output from YCbCr image),
158 * we can skip most computations for the unused components.
159 */
160 boolean component_needed; /* do we need the value of this component? */
161
162 /* These values are computed before starting a scan of the component. */
163 /* The decompressor output side may not use these variables. */
164 int MCU_width; /* number of blocks per MCU, horizontally */
165 int MCU_height; /* number of blocks per MCU, vertically */
166 int MCU_blocks; /* MCU_width * MCU_height */
167 int MCU_sample_width; /* MCU width in samples, MCU_width*DCT_scaled_size */
168 int last_col_width; /* # of non-dummy blocks across in last MCU */
169 int last_row_height; /* # of non-dummy blocks down in last MCU */
170
171 /* Saved quantization table for component; NULL if none yet saved.
172 * See jdinput.c comments about the need for this information.
173 * This field is currently used only for decompression.
174 */
175 JQUANT_TBL * quant_table;
176
177 /* Private per-component storage for DCT or IDCT subsystem. */
178 void * dct_table;
179 } jpeg_component_info;
180
181
182 /* The script for encoding a multiple-scan file is an array of these: */
183
184 typedef struct {
185 int comps_in_scan; /* number of components encoded in this scan */
186 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
187 int Ss, Se; /* progressive JPEG spectral selection parms */
188 int Ah, Al; /* progressive JPEG successive approx. parms */
189 } jpeg_scan_info;
190
191 /* The decompressor can save APPn and COM markers in a list of these: */
192
193 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr;
194
195 struct jpeg_marker_struct {
196 jpeg_saved_marker_ptr next; /* next in list, or NULL */
197 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */
198 unsigned int original_length; /* # bytes of data in the file */
199 unsigned int data_length; /* # bytes of data saved at data[] */
200 JOCTET FAR * data; /* the data contained in the marker */
201 /* the marker length word is not counted in data_length or original_length */
202 };
203
204 /* Known color spaces. */
205
206 typedef enum {
207 JCS_UNKNOWN, /* error/unspecified */
208 JCS_GRAYSCALE, /* monochrome */
209 JCS_RGB, /* red/green/blue */
210 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */
211 JCS_CMYK, /* C/M/Y/K */
212 JCS_YCCK /* Y/Cb/Cr/K */
213 } J_COLOR_SPACE;
214
215 /* DCT/IDCT algorithm options. */
216
217 typedef enum {
218 JDCT_ISLOW, /* slow but accurate integer algorithm */
219 JDCT_IFAST, /* faster, less accurate integer method */
220 JDCT_FLOAT /* floating-point: accurate, fast on fast HW */
221 } J_DCT_METHOD;
222
223 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */
224 #define JDCT_DEFAULT JDCT_ISLOW
225 #endif
226 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */
227 #define JDCT_FASTEST JDCT_IFAST
228 #endif
229
230 /* Dithering options for decompression. */
231
232 typedef enum {
233 JDITHER_NONE, /* no dithering */
234 JDITHER_ORDERED, /* simple ordered dither */
235 JDITHER_FS /* Floyd-Steinberg error diffusion dither */
236 } J_DITHER_MODE;
237
238
239 /* Common fields between JPEG compression and decompression master structs. */
240
241 #define jpeg_common_fields \
242 struct jpeg_error_mgr * err; /* Error handler module */\
243 struct jpeg_memory_mgr * mem; /* Memory manager module */\
244 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
245 void * client_data; /* Available for use by application */\
246 boolean is_decompressor; /* So common code can tell which is which */\
247 int global_state /* For checking call sequence validity */
248
249 /* Routines that are to be used by both halves of the library are declared
250 * to receive a pointer to this structure. There are no actual instances of
251 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
252 */
253 struct jpeg_common_struct {
254 jpeg_common_fields; /* Fields common to both master struct types */
255 /* Additional fields follow in an actual jpeg_compress_struct or
256 * jpeg_decompress_struct. All three structs must agree on these
257 * initial fields! (This would be a lot cleaner in C++.)
258 */
259 };
260
261 typedef struct jpeg_common_struct * j_common_ptr;
262 typedef struct jpeg_compress_struct * j_compress_ptr;
263 typedef struct jpeg_decompress_struct * j_decompress_ptr;
264
265
266 /* Master record for a compression instance */
267
268 struct jpeg_compress_struct {
269 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */
270
271 /* Destination for compressed data */
272 struct jpeg_destination_mgr * dest;
273
274 /* Description of source image --- these fields must be filled in by
275 * outer application before starting compression. in_color_space must
276 * be correct before you can even call jpeg_set_defaults().
277 */
278
279 JDIMENSION image_width; /* input image width */
280 JDIMENSION image_height; /* input image height */
281 int input_components; /* # of color components in input image */
282 J_COLOR_SPACE in_color_space; /* colorspace of input image */
283
284 double input_gamma; /* image gamma of input image */
285
286 /* Compression parameters --- these fields must be set before calling
287 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to
288 * initialize everything to reasonable defaults, then changing anything
289 * the application specifically wants to change. That way you won't get
290 * burnt when new parameters are added. Also note that there are several
291 * helper routines to simplify changing parameters.
292 */
293
294 int data_precision; /* bits of precision in image data */
295
296 int num_components; /* # of color components in JPEG image */
297 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
298
299 jpeg_component_info * comp_info;
300 /* comp_info[i] describes component that appears i'th in SOF */
301
302 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
303 /* ptrs to coefficient quantization tables, or NULL if not defined */
304
305 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
306 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
307 /* ptrs to Huffman coding tables, or NULL if not defined */
308
309 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
310 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
311 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
312
313 int num_scans; /* # of entries in scan_info array */
314 const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
315 /* The default value of scan_info is NULL, which causes a single-scan
316 * sequential JPEG file to be emitted. To create a multi-scan file,
317 * set num_scans and scan_info to point to an array of scan definitions.
318 */
319
320 boolean raw_data_in; /* TRUE=caller supplies downsampled data */
321 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
322 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */
323 boolean CCIR601_sampling; /* TRUE=first samples are cosited */
324 int smoothing_factor; /* 1..100, or 0 for no input smoothing */
325 J_DCT_METHOD dct_method; /* DCT algorithm selector */
326
327 /* The restart interval can be specified in absolute MCUs by setting
328 * restart_interval, or in MCU rows by setting restart_in_rows
329 * (in which case the correct restart_interval will be figured
330 * for each scan).
331 */
332 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
333 int restart_in_rows; /* if > 0, MCU rows per restart interval */
334
335 /* Parameters controlling emission of special markers. */
336
337 boolean write_JFIF_header; /* should a JFIF marker be written? */
338 UINT8 JFIF_major_version; /* What to write for the JFIF version number */
339 UINT8 JFIF_minor_version;
340 /* These three values are not used by the JPEG code, merely copied */
341 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */
342 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */
343 /* ratio is defined by X_density/Y_density even when density_unit=0. */
344 UINT8 density_unit; /* JFIF code for pixel size units */
345 UINT16 X_density; /* Horizontal pixel density */
346 UINT16 Y_density; /* Vertical pixel density */
347 boolean write_Adobe_marker; /* should an Adobe marker be written? */
348
349 /* State variable: index of next scanline to be written to
350 * jpeg_write_scanlines(). Application may use this to control its
351 * processing loop, e.g., "while (next_scanline < image_height)".
352 */
353
354 JDIMENSION next_scanline; /* 0 .. image_height-1 */
355
356 /* Remaining fields are known throughout compressor, but generally
357 * should not be touched by a surrounding application.
358 */
359
360 /*
361 * These fields are computed during compression startup
362 */
363 boolean progressive_mode; /* TRUE if scan script uses progressive mode */
364 int max_h_samp_factor; /* largest h_samp_factor */
365 int max_v_samp_factor; /* largest v_samp_factor */
366
367 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */
368 /* The coefficient controller receives data in units of MCU rows as defined
369 * for fully interleaved scans (whether the JPEG file is interleaved or not).
370 * There are v_samp_factor * DCTSIZE sample rows of each component in an
371 * "iMCU" (interleaved MCU) row.
372 */
373
374 /*
375 * These fields are valid during any one scan.
376 * They describe the components and MCUs actually appearing in the scan.
377 */
378 int comps_in_scan; /* # of JPEG components in this scan */
379 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
380 /* *cur_comp_info[i] describes component that appears i'th in SOS */
381
382 JDIMENSION MCUs_per_row; /* # of MCUs across the image */
383 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
384
385 int blocks_in_MCU; /* # of DCT blocks per MCU */
386 int MCU_membership[C_MAX_BLOCKS_IN_MCU];
387 /* MCU_membership[i] is index in cur_comp_info of component owning */
388 /* i'th block in an MCU */
389
390 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
391
392 /*
393 * Links to compression subobjects (methods and private variables of modules)
394 */
395 struct jpeg_comp_master * master;
396 struct jpeg_c_main_controller * main;
397 struct jpeg_c_prep_controller * prep;
398 struct jpeg_c_coef_controller * coef;
399 struct jpeg_marker_writer * marker;
400 struct jpeg_color_converter * cconvert;
401 struct jpeg_downsampler * downsample;
402 struct jpeg_forward_dct * fdct;
403 struct jpeg_entropy_encoder * entropy;
404 jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */
405 int script_space_size;
406 };
407
408
409 /* Master record for a decompression instance */
410
411 struct jpeg_decompress_struct {
412 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */
413
414 /* Source of compressed data */
415 struct jpeg_source_mgr * src;
416
417 /* Basic description of image --- filled in by jpeg_read_header(). */
418 /* Application may inspect these values to decide how to process image. */
419
420 JDIMENSION image_width; /* nominal image width (from SOF marker) */
421 JDIMENSION image_height; /* nominal image height */
422 int num_components; /* # of color components in JPEG image */
423 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
424
425 /* Decompression processing parameters --- these fields must be set before
426 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes
427 * them to default values.
428 */
429
430 J_COLOR_SPACE out_color_space; /* colorspace for output */
431
432 unsigned int scale_num, scale_denom; /* fraction by which to scale image */
433
434 double output_gamma; /* image gamma wanted in output */
435
436 boolean buffered_image; /* TRUE=multiple output passes */
437 boolean raw_data_out; /* TRUE=downsampled data wanted */
438
439 J_DCT_METHOD dct_method; /* IDCT algorithm selector */
440 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */
441 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */
442
443 boolean quantize_colors; /* TRUE=colormapped output wanted */
444 /* the following are ignored if not quantize_colors: */
445 J_DITHER_MODE dither_mode; /* type of color dithering to use */
446 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */
447 int desired_number_of_colors; /* max # colors to use in created colormap */
448 /* these are significant only in buffered-image mode: */
449 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */
450 boolean enable_external_quant;/* enable future use of external colormap */
451 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */
452
453 /* Description of actual output image that will be returned to application.
454 * These fields are computed by jpeg_start_decompress().
455 * You can also use jpeg_calc_output_dimensions() to determine these values
456 * in advance of calling jpeg_start_decompress().
457 */
458
459 JDIMENSION output_width; /* scaled image width */
460 JDIMENSION output_height; /* scaled image height */
461 int out_color_components; /* # of color components in out_color_space */
462 int output_components; /* # of color components returned */
463 /* output_components is 1 (a colormap index) when quantizing colors;
464 * otherwise it equals out_color_components.
465 */
466 int rec_outbuf_height; /* min recommended height of scanline buffer */
467 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
468 * high, space and time will be wasted due to unnecessary data copying.
469 * Usually rec_outbuf_height will be 1 or 2, at most 4.
470 */
471
472 /* When quantizing colors, the output colormap is described by these fields.
473 * The application can supply a colormap by setting colormap non-NULL before
474 * calling jpeg_start_decompress; otherwise a colormap is created during
475 * jpeg_start_decompress or jpeg_start_output.
476 * The map has out_color_components rows and actual_number_of_colors columns.
477 */
478 int actual_number_of_colors; /* number of entries in use */
479 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */
480
481 /* State variables: these variables indicate the progress of decompression.
482 * The application may examine these but must not modify them.
483 */
484
485 /* Row index of next scanline to be read from jpeg_read_scanlines().
486 * Application may use this to control its processing loop, e.g.,
487 * "while (output_scanline < output_height)".
488 */
489 JDIMENSION output_scanline; /* 0 .. output_height-1 */
490
491 /* Current input scan number and number of iMCU rows completed in scan.
492 * These indicate the progress of the decompressor input side.
493 */
494 int input_scan_number; /* Number of SOS markers seen so far */
495 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */
496
497 /* The "output scan number" is the notional scan being displayed by the
498 * output side. The decompressor will not allow output scan/row number
499 * to get ahead of input scan/row, but it can fall arbitrarily far behind.
500 */
501 int output_scan_number; /* Nominal scan number being displayed */
502 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */
503
504 /* Current progression status. coef_bits[c][i] indicates the precision
505 * with which component c's DCT coefficient i (in zigzag order) is known.
506 * It is -1 when no data has yet been received, otherwise it is the point
507 * transform (shift) value for the most recent scan of the coefficient
508 * (thus, 0 at completion of the progression).
509 * This pointer is NULL when reading a non-progressive file.
510 */
511 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */
512
513 /* Internal JPEG parameters --- the application usually need not look at
514 * these fields. Note that the decompressor output side may not use
515 * any parameters that can change between scans.
516 */
517
518 /* Quantization and Huffman tables are carried forward across input
519 * datastreams when processing abbreviated JPEG datastreams.
520 */
521
522 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
523 /* ptrs to coefficient quantization tables, or NULL if not defined */
524
525 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
526 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
527 /* ptrs to Huffman coding tables, or NULL if not defined */
528
529 /* These parameters are never carried across datastreams, since they
530 * are given in SOF/SOS markers or defined to be reset by SOI.
531 */
532
533 int data_precision; /* bits of precision in image data */
534
535 jpeg_component_info * comp_info;
536 /* comp_info[i] describes component that appears i'th in SOF */
537
538 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */
539 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
540
541 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
542 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
543 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
544
545 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
546
547 /* These fields record data obtained from optional markers recognized by
548 * the JPEG library.
549 */
550 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */
551 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
552 UINT8 JFIF_major_version; /* JFIF version number */
553 UINT8 JFIF_minor_version;
554 UINT8 density_unit; /* JFIF code for pixel size units */
555 UINT16 X_density; /* Horizontal pixel density */
556 UINT16 Y_density; /* Vertical pixel density */
557 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */
558 UINT8 Adobe_transform; /* Color transform code from Adobe marker */
559
560 boolean CCIR601_sampling; /* TRUE=first samples are cosited */
561
562 /* Aside from the specific data retained from APPn markers known to the
563 * library, the uninterpreted contents of any or all APPn and COM markers
564 * can be saved in a list for examination by the application.
565 */
566 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
567
568 /* Remaining fields are known throughout decompressor, but generally
569 * should not be touched by a surrounding application.
570 */
571
572 /*
573 * These fields are computed during decompression startup
574 */
575 int max_h_samp_factor; /* largest h_samp_factor */
576 int max_v_samp_factor; /* largest v_samp_factor */
577
578 int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */
579
580 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */
581 /* The coefficient controller's input and output progress is measured in
582 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows
583 * in fully interleaved JPEG scans, but are used whether the scan is
584 * interleaved or not. We define an iMCU row as v_samp_factor DCT block
585 * rows of each component. Therefore, the IDCT output contains
586 * v_samp_factor*DCT_scaled_size sample rows of a component per iMCU row.
587 */
588
589 JSAMPLE * sample_range_limit; /* table for fast range-limiting */
590
591 /*
592 * These fields are valid during any one scan.
593 * They describe the components and MCUs actually appearing in the scan.
594 * Note that the decompressor output side must not use these fields.
595 */
596 int comps_in_scan; /* # of JPEG components in this scan */
597 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
598 /* *cur_comp_info[i] describes component that appears i'th in SOS */
599
600 JDIMENSION MCUs_per_row; /* # of MCUs across the image */
601 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
602
603 int blocks_in_MCU; /* # of DCT blocks per MCU */
604 int MCU_membership[D_MAX_BLOCKS_IN_MCU];
605 /* MCU_membership[i] is index in cur_comp_info of component owning */
606 /* i'th block in an MCU */
607
608 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
609
610 /* This field is shared between entropy decoder and marker parser.
611 * It is either zero or the code of a JPEG marker that has been
612 * read from the data source, but has not yet been processed.
613 */
614 int unread_marker;
615
616 /*
617 * Links to decompression subobjects (methods, private variables of modules)
618 */
619 struct jpeg_decomp_master * master;
620 struct jpeg_d_main_controller * main;
621 struct jpeg_d_coef_controller * coef;
622 struct jpeg_d_post_controller * post;
623 struct jpeg_input_controller * inputctl;
624 struct jpeg_marker_reader * marker;
625 struct jpeg_entropy_decoder * entropy;
626 struct jpeg_inverse_dct * idct;
627 struct jpeg_upsampler * upsample;
628 struct jpeg_color_deconverter * cconvert;
629 struct jpeg_color_quantizer * cquantize;
630 };
631
632
633 /* "Object" declarations for JPEG modules that may be supplied or called
634 * directly by the surrounding application.
635 * As with all objects in the JPEG library, these structs only define the
636 * publicly visible methods and state variables of a module. Additional
637 * private fields may exist after the public ones.
638 */
639
640
641 /* Error handler object */
642
643 struct jpeg_error_mgr {
644 /* Error exit handler: does not return to caller */
645 JMETHOD(void, error_exit, (j_common_ptr cinfo));
646 /* Conditionally emit a trace or warning message */
647 JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
648 /* Routine that actually outputs a trace or error message */
649 JMETHOD(void, output_message, (j_common_ptr cinfo));
650 /* Format a message string for the most recent JPEG error or message */
651 JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
652 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */
653 /* Reset error state variables at start of a new image */
654 JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
655
656 /* The message ID code and any parameters are saved here.
657 * A message can have one string parameter or up to 8 int parameters.
658 */
659 int msg_code;
660 #define JMSG_STR_PARM_MAX 80
661 union {
662 int i[8];
663 char s[JMSG_STR_PARM_MAX];
664 } msg_parm;
665
666 /* Standard state variables for error facility */
667
668 int trace_level; /* max msg_level that will be displayed */
669
670 /* For recoverable corrupt-data errors, we emit a warning message,
671 * but keep going unless emit_message chooses to abort. emit_message
672 * should count warnings in num_warnings. The surrounding application
673 * can check for bad data by seeing if num_warnings is nonzero at the
674 * end of processing.
675 */
676 long num_warnings; /* number of corrupt-data warnings */
677
678 /* These fields point to the table(s) of error message strings.
679 * An application can change the table pointer to switch to a different
680 * message list (typically, to change the language in which errors are
681 * reported). Some applications may wish to add additional error codes
682 * that will be handled by the JPEG library error mechanism; the second
683 * table pointer is used for this purpose.
684 *
685 * First table includes all errors generated by JPEG library itself.
686 * Error code 0 is reserved for a "no such error string" message.
687 */
688 const char * const * jpeg_message_table; /* Library errors */
689 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */
690 /* Second table can be added by application (see cjpeg/djpeg for example).
691 * It contains strings numbered first_addon_message..last_addon_message.
692 */
693 const char * const * addon_message_table; /* Non-library errors */
694 int first_addon_message; /* code for first string in addon table */
695 int last_addon_message; /* code for last string in addon table */
696 };
697
698
699 /* Progress monitor object */
700
701 struct jpeg_progress_mgr {
702 JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
703
704 long pass_counter; /* work units completed in this pass */
705 long pass_limit; /* total number of work units in this pass */
706 int completed_passes; /* passes completed so far */
707 int total_passes; /* total number of passes expected */
708 };
709
710
711 /* Data destination object for compression */
712
713 struct jpeg_destination_mgr {
714 JOCTET * next_output_byte; /* => next byte to write in buffer */
715 size_t free_in_buffer; /* # of byte spaces remaining in buffer */
716
717 JMETHOD(void, init_destination, (j_compress_ptr cinfo));
718 JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
719 JMETHOD(void, term_destination, (j_compress_ptr cinfo));
720 };
721
722
723 /* Data source object for decompression */
724
725 struct jpeg_source_mgr {
726 const JOCTET * next_input_byte; /* => next byte to read from buffer */
727 size_t bytes_in_buffer; /* # of bytes remaining in buffer */
728
729 JMETHOD(void, init_source, (j_decompress_ptr cinfo));
730 JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
731 JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
732 JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
733 JMETHOD(void, term_source, (j_decompress_ptr cinfo));
734 };
735
736
737 /* Memory manager object.
738 * Allocates "small" objects (a few K total), "large" objects (tens of K),
739 * and "really big" objects (virtual arrays with backing store if needed).
740 * The memory manager does not allow individual objects to be freed; rather,
741 * each created object is assigned to a pool, and whole pools can be freed
742 * at once. This is faster and more convenient than remembering exactly what
743 * to free, especially where malloc()/free() are not too speedy.
744 * NB: alloc routines never return NULL. They exit to error_exit if not
745 * successful.
746 */
747
748 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */
749 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */
750 #define JPOOL_NUMPOOLS 2
751
752 typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
753 typedef struct jvirt_barray_control * jvirt_barray_ptr;
754
755
756 struct jpeg_memory_mgr {
757 /* Method pointers */
758 JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
759 size_t sizeofobject));
760 JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
761 size_t sizeofobject));
762 JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
763 JDIMENSION samplesperrow,
764 JDIMENSION numrows));
765 JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
766 JDIMENSION blocksperrow,
767 JDIMENSION numrows));
768 JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
769 int pool_id,
770 boolean pre_zero,
771 JDIMENSION samplesperrow,
772 JDIMENSION numrows,
773 JDIMENSION maxaccess));
774 JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
775 int pool_id,
776 boolean pre_zero,
777 JDIMENSION blocksperrow,
778 JDIMENSION numrows,
779 JDIMENSION maxaccess));
780 JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
781 JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
782 jvirt_sarray_ptr ptr,
783 JDIMENSION start_row,
784 JDIMENSION num_rows,
785 boolean writable));
786 JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
787 jvirt_barray_ptr ptr,
788 JDIMENSION start_row,
789 JDIMENSION num_rows,
790 boolean writable));
791 JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
792 JMETHOD(void, self_destruct, (j_common_ptr cinfo));
793
794 /* Limit on memory allocation for this JPEG object. (Note that this is
795 * merely advisory, not a guaranteed maximum; it only affects the space
796 * used for virtual-array buffers.) May be changed by outer application
797 * after creating the JPEG object.
798 */
799 long max_memory_to_use;
800
801 /* Maximum allocation request accepted by alloc_large. */
802 long max_alloc_chunk;
803 };
804
805
806 /* Routine signature for application-supplied marker processing methods.
807 * Need not pass marker code since it is stored in cinfo->unread_marker.
808 */
809 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
810
811
812 /* Declarations for routines called by application.
813 * The JPP macro hides prototype parameters from compilers that can't cope.
814 * Note JPP requires double parentheses.
815 */
816
817 #ifdef HAVE_PROTOTYPES
818 #define JPP(arglist) arglist
819 #else
820 #define JPP(arglist) ()
821 #endif
822
823
824 /* Short forms of external names for systems with brain-damaged linkers.
825 * We shorten external names to be unique in the first six letters, which
826 * is good enough for all known systems.
827 * (If your compiler itself needs names to be unique in less than 15
828 * characters, you are out of luck. Get a better compiler.)
829 */
830
831 #ifdef NEED_SHORT_EXTERNAL_NAMES
832 #define jpeg_std_error jStdError
833 #define jpeg_CreateCompress jCreaCompress
834 #define jpeg_CreateDecompress jCreaDecompress
835 #define jpeg_destroy_compress jDestCompress
836 #define jpeg_destroy_decompress jDestDecompress
837 #define jpeg_stdio_dest jStdDest
838 #define jpeg_stdio_src jStdSrc
839 #define jpeg_set_defaults jSetDefaults
840 #define jpeg_set_colorspace jSetColorspace
841 #define jpeg_default_colorspace jDefColorspace
842 #define jpeg_set_quality jSetQuality
843 #define jpeg_set_linear_quality jSetLQuality
844 #define jpeg_add_quant_table jAddQuantTable
845 #define jpeg_quality_scaling jQualityScaling
846 #define jpeg_simple_progression jSimProgress
847 #define jpeg_suppress_tables jSuppressTables
848 #define jpeg_alloc_quant_table jAlcQTable
849 #define jpeg_alloc_huff_table jAlcHTable
850 #define jpeg_start_compress jStrtCompress
851 #define jpeg_write_scanlines jWrtScanlines
852 #define jpeg_finish_compress jFinCompress
853 #define jpeg_write_raw_data jWrtRawData
854 #define jpeg_write_marker jWrtMarker
855 #define jpeg_write_m_header jWrtMHeader
856 #define jpeg_write_m_byte jWrtMByte
857 #define jpeg_write_tables jWrtTables
858 #define jpeg_read_header jReadHeader
859 #define jpeg_start_decompress jStrtDecompress
860 #define jpeg_read_scanlines jReadScanlines
861 #define jpeg_finish_decompress jFinDecompress
862 #define jpeg_read_raw_data jReadRawData
863 #define jpeg_has_multiple_scans jHasMultScn
864 #define jpeg_start_output jStrtOutput
865 #define jpeg_finish_output jFinOutput
866 #define jpeg_input_complete jInComplete
867 #define jpeg_new_colormap jNewCMap
868 #define jpeg_consume_input jConsumeInput
869 #define jpeg_calc_output_dimensions jCalcDimensions
870 #define jpeg_save_markers jSaveMarkers
871 #define jpeg_set_marker_processor jSetMarker
872 #define jpeg_read_coefficients jReadCoefs
873 #define jpeg_write_coefficients jWrtCoefs
874 #define jpeg_copy_critical_parameters jCopyCrit
875 #define jpeg_abort_compress jAbrtCompress
876 #define jpeg_abort_decompress jAbrtDecompress
877 #define jpeg_abort jAbort
878 #define jpeg_destroy jDestroy
879 #define jpeg_resync_to_restart jResyncRestart
880 #endif /* NEED_SHORT_EXTERNAL_NAMES */
881
882
883 /* Default error-management setup */
884 EXTERN(struct jpeg_error_mgr *) jpeg_std_error
885 JPP((struct jpeg_error_mgr * err));
886
887 /* Initialization of JPEG compression objects.
888 * jpeg_create_compress() and jpeg_create_decompress() are the exported
889 * names that applications should call. These expand to calls on
890 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
891 * passed for version mismatch checking.
892 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
893 */
894 #define jpeg_create_compress(cinfo) \
895 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
896 (size_t) sizeof(struct jpeg_compress_struct))
897 #define jpeg_create_decompress(cinfo) \
898 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
899 (size_t) sizeof(struct jpeg_decompress_struct))
900 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo,
901 int version, size_t structsize));
902 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
903 int version, size_t structsize));
904 /* Destruction of JPEG compression objects */
905 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
906 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
907
908 /* Standard data source and destination managers: stdio streams. */
909 /* Caller is responsible for opening the file before and closing after. */
910 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
911 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
912
913 /* Default parameter setup for compression */
914 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
915 /* Compression parameter setup aids */
916 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
917 J_COLOR_SPACE colorspace));
918 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
919 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
920 boolean force_baseline));
921 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
922 int scale_factor,
923 boolean force_baseline));
924 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
925 const unsigned int *basic_table,
926 int scale_factor,
927 boolean force_baseline));
928 EXTERN(int) jpeg_quality_scaling JPP((int quality));
929 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
930 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
931 boolean suppress));
932 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
933 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
934
935 /* Main entry points for compression */
936 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
937 boolean write_all_tables));
938 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
939 JSAMPARRAY scanlines,
940 JDIMENSION num_lines));
941 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
942
943 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
944 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
945 JSAMPIMAGE data,
946 JDIMENSION num_lines));
947
948 /* Write a special marker. See libjpeg.doc concerning safe usage. */
949 EXTERN(void) jpeg_write_marker
950 JPP((j_compress_ptr cinfo, int marker,
951 const JOCTET * dataptr, unsigned int datalen));
952 /* Same, but piecemeal. */
953 EXTERN(void) jpeg_write_m_header
954 JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
955 EXTERN(void) jpeg_write_m_byte
956 JPP((j_compress_ptr cinfo, int val));
957
958 /* Alternate compression function: just write an abbreviated table file */
959 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
960
961 /* Decompression startup: read start of JPEG datastream to see what's there */
962 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo,
963 boolean require_image));
964 /* Return value is one of: */
965 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */
966 #define JPEG_HEADER_OK 1 /* Found valid image datastream */
967 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */
968 /* If you pass require_image = TRUE (normal case), you need not check for
969 * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
970 * JPEG_SUSPENDED is only possible if you use a data source module that can
971 * give a suspension return (the stdio source module doesn't).
972 */
973
974 /* Main entry points for decompression */
975 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo));
976 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
977 JSAMPARRAY scanlines,
978 JDIMENSION max_lines));
979 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
980
981 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
982 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
983 JSAMPIMAGE data,
984 JDIMENSION max_lines));
985
986 /* Additional entry points for buffered-image mode. */
987 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
988 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
989 int scan_number));
990 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
991 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
992 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
993 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo));
994 /* Return value is one of: */
995 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */
996 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */
997 #define JPEG_REACHED_EOI 2 /* Reached end of image */
998 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */
999 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */
1000
1001 /* Precalculate output dimensions for current decompression parameters. */
1002 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
1003
1004 /* Control saving of COM and APPn markers into marker_list. */
1005 EXTERN(void) jpeg_save_markers
1006 JPP((j_decompress_ptr cinfo, int marker_code,
1007 unsigned int length_limit));
1008
1009 /* Install a special processing method for COM or APPn markers. */
1010 EXTERN(void) jpeg_set_marker_processor
1011 JPP((j_decompress_ptr cinfo, int marker_code,
1012 jpeg_marker_parser_method routine));
1013
1014 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
1015 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
1016 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
1017 jvirt_barray_ptr * coef_arrays));
1018 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
1019 j_compress_ptr dstinfo));
1020
1021 /* If you choose to abort compression or decompression before completing
1022 * jpeg_finish_(de)compress, then you need to clean up to release memory,
1023 * temporary files, etc. You can just call jpeg_destroy_(de)compress
1024 * if you're done with the JPEG object, but if you want to clean it up and
1025 * reuse it, call this:
1026 */
1027 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo));
1028 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
1029
1030 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
1031 * flavor of JPEG object. These may be more convenient in some places.
1032 */
1033 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo));
1034 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
1035
1036 /* Default restart-marker-resync procedure for use by data source modules */
1037 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
1038 int desired));
1039
1040
1041 /* These marker codes are exported since applications and data source modules
1042 * are likely to want to use them.
1043 */
1044
1045 #define JPEG_RST0 0xD0 /* RST0 marker code */
1046 #define JPEG_EOI 0xD9 /* EOI marker code */
1047 #define JPEG_APP0 0xE0 /* APP0 marker code */
1048 #define JPEG_COM 0xFE /* COM marker code */
1049
1050
1051 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
1052 * for structure definitions that are never filled in, keep it quiet by
1053 * supplying dummy definitions for the various substructures.
1054 */
1055
1056 #ifdef INCOMPLETE_TYPES_BROKEN
1057 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */
1058 struct jvirt_sarray_control { long dummy; };
1059 struct jvirt_barray_control { long dummy; };
1060 struct jpeg_comp_master { long dummy; };
1061 struct jpeg_c_main_controller { long dummy; };
1062 struct jpeg_c_prep_controller { long dummy; };
1063 struct jpeg_c_coef_controller { long dummy; };
1064 struct jpeg_marker_writer { long dummy; };
1065 struct jpeg_color_converter { long dummy; };
1066 struct jpeg_downsampler { long dummy; };
1067 struct jpeg_forward_dct { long dummy; };
1068 struct jpeg_entropy_encoder { long dummy; };
1069 struct jpeg_decomp_master { long dummy; };
1070 struct jpeg_d_main_controller { long dummy; };
1071 struct jpeg_d_coef_controller { long dummy; };
1072 struct jpeg_d_post_controller { long dummy; };
1073 struct jpeg_input_controller { long dummy; };
1074 struct jpeg_marker_reader { long dummy; };
1075 struct jpeg_entropy_decoder { long dummy; };
1076 struct jpeg_inverse_dct { long dummy; };
1077 struct jpeg_upsampler { long dummy; };
1078 struct jpeg_color_deconverter { long dummy; };
1079 struct jpeg_color_quantizer { long dummy; };
1080 #endif /* JPEG_INTERNALS */
1081 #endif /* INCOMPLETE_TYPES_BROKEN */
1082
1083
1084 /*
1085 * The JPEG library modules define JPEG_INTERNALS before including this file.
1086 * The internal structure declarations are read only when that is true.
1087 * Applications using the library should not include jpegint.h, but may wish
1088 * to include jerror.h.
1089 */
1090
1091 #ifdef JPEG_INTERNALS
1092 #include "jpegint.h" /* fetch private declarations */
1093 #include "jerror.h" /* fetch error codes too */
1094 #endif
1095
1096 #endif /* JPEGLIB_H */