|
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 */ |