]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * jpegint.h | |
3 | * | |
4 | * Copyright (C) 1991-1997, 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 provides common declarations for the various JPEG modules. | |
9 | * These declarations are considered internal to the JPEG library; most | |
10 | * applications using the library shouldn't need to include this file. | |
11 | */ | |
12 | ||
13 | ||
14 | /* Declarations for both compression & decompression */ | |
15 | ||
16 | typedef enum { /* Operating modes for buffer controllers */ | |
17 | JBUF_PASS_THRU, /* Plain stripwise operation */ | |
18 | /* Remaining modes require a full-image buffer to have been created */ | |
19 | JBUF_SAVE_SOURCE, /* Run source subobject only, save output */ | |
20 | JBUF_CRANK_DEST, /* Run dest subobject only, using saved data */ | |
21 | JBUF_SAVE_AND_PASS /* Run both subobjects, save output */ | |
22 | } J_BUF_MODE; | |
23 | ||
24 | /* Values of global_state field (jdapi.c has some dependencies on ordering!) */ | |
25 | #define CSTATE_START 100 /* after create_compress */ | |
26 | #define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */ | |
27 | #define CSTATE_RAW_OK 102 /* start_compress done, write_raw_data OK */ | |
28 | #define CSTATE_WRCOEFS 103 /* jpeg_write_coefficients done */ | |
29 | #define DSTATE_START 200 /* after create_decompress */ | |
30 | #define DSTATE_INHEADER 201 /* reading header markers, no SOS yet */ | |
31 | #define DSTATE_READY 202 /* found SOS, ready for start_decompress */ | |
32 | #define DSTATE_PRELOAD 203 /* reading multiscan file in start_decompress*/ | |
33 | #define DSTATE_PRESCAN 204 /* performing dummy pass for 2-pass quant */ | |
34 | #define DSTATE_SCANNING 205 /* start_decompress done, read_scanlines OK */ | |
35 | #define DSTATE_RAW_OK 206 /* start_decompress done, read_raw_data OK */ | |
36 | #define DSTATE_BUFIMAGE 207 /* expecting jpeg_start_output */ | |
37 | #define DSTATE_BUFPOST 208 /* looking for SOS/EOI in jpeg_finish_output */ | |
38 | #define DSTATE_RDCOEFS 209 /* reading file in jpeg_read_coefficients */ | |
39 | #define DSTATE_STOPPING 210 /* looking for EOI in jpeg_finish_decompress */ | |
40 | ||
41 | ||
42 | /* Declarations for compression modules */ | |
43 | ||
44 | /* Master control module */ | |
45 | struct jpeg_comp_master { | |
46 | JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo)); | |
47 | JMETHOD(void, pass_startup, (j_compress_ptr cinfo)); | |
48 | JMETHOD(void, finish_pass, (j_compress_ptr cinfo)); | |
49 | ||
50 | /* State variables made visible to other modules */ | |
51 | boolean call_pass_startup; /* True if pass_startup must be called */ | |
52 | boolean is_last_pass; /* True during last pass */ | |
53 | }; | |
54 | ||
55 | /* Main buffer control (downsampled-data buffer) */ | |
56 | struct jpeg_c_main_controller { | |
57 | JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); | |
58 | JMETHOD(void, process_data, (j_compress_ptr cinfo, | |
59 | JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, | |
60 | JDIMENSION in_rows_avail)); | |
61 | }; | |
62 | ||
63 | /* Compression preprocessing (downsampling input buffer control) */ | |
64 | struct jpeg_c_prep_controller { | |
65 | JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); | |
66 | JMETHOD(void, pre_process_data, (j_compress_ptr cinfo, | |
67 | JSAMPARRAY input_buf, | |
68 | JDIMENSION *in_row_ctr, | |
69 | JDIMENSION in_rows_avail, | |
70 | JSAMPIMAGE output_buf, | |
71 | JDIMENSION *out_row_group_ctr, | |
72 | JDIMENSION out_row_groups_avail)); | |
73 | }; | |
74 | ||
75 | /* Coefficient buffer control */ | |
76 | struct jpeg_c_coef_controller { | |
77 | JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); | |
78 | JMETHOD(boolean, compress_data, (j_compress_ptr cinfo, | |
79 | JSAMPIMAGE input_buf)); | |
80 | }; | |
81 | ||
82 | /* Colorspace conversion */ | |
83 | struct jpeg_color_converter { | |
84 | JMETHOD(void, start_pass, (j_compress_ptr cinfo)); | |
85 | JMETHOD(void, color_convert, (j_compress_ptr cinfo, | |
86 | JSAMPARRAY input_buf, JSAMPIMAGE output_buf, | |
87 | JDIMENSION output_row, int num_rows)); | |
88 | }; | |
89 | ||
90 | /* Downsampling */ | |
91 | struct jpeg_downsampler { | |
92 | JMETHOD(void, start_pass, (j_compress_ptr cinfo)); | |
93 | JMETHOD(void, downsample, (j_compress_ptr cinfo, | |
94 | JSAMPIMAGE input_buf, JDIMENSION in_row_index, | |
95 | JSAMPIMAGE output_buf, | |
96 | JDIMENSION out_row_group_index)); | |
97 | ||
98 | boolean need_context_rows; /* TRUE if need rows above & below */ | |
99 | }; | |
100 | ||
101 | /* Forward DCT (also controls coefficient quantization) */ | |
102 | struct jpeg_forward_dct { | |
103 | JMETHOD(void, start_pass, (j_compress_ptr cinfo)); | |
104 | /* perhaps this should be an array??? */ | |
105 | JMETHOD(void, forward_DCT, (j_compress_ptr cinfo, | |
106 | jpeg_component_info * compptr, | |
107 | JSAMPARRAY sample_data, JBLOCKROW coef_blocks, | |
108 | JDIMENSION start_row, JDIMENSION start_col, | |
109 | JDIMENSION num_blocks)); | |
110 | }; | |
111 | ||
112 | /* Entropy encoding */ | |
113 | struct jpeg_entropy_encoder { | |
114 | JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics)); | |
115 | JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data)); | |
116 | JMETHOD(void, finish_pass, (j_compress_ptr cinfo)); | |
117 | }; | |
118 | ||
119 | /* Marker writing */ | |
120 | struct jpeg_marker_writer { | |
121 | JMETHOD(void, write_file_header, (j_compress_ptr cinfo)); | |
122 | JMETHOD(void, write_frame_header, (j_compress_ptr cinfo)); | |
123 | JMETHOD(void, write_scan_header, (j_compress_ptr cinfo)); | |
124 | JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo)); | |
125 | JMETHOD(void, write_tables_only, (j_compress_ptr cinfo)); | |
126 | /* These routines are exported to allow insertion of extra markers */ | |
127 | /* Probably only COM and APPn markers should be written this way */ | |
128 | JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker, | |
129 | unsigned int datalen)); | |
130 | JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val)); | |
131 | }; | |
132 | ||
133 | ||
134 | /* Declarations for decompression modules */ | |
135 | ||
136 | /* Master control module */ | |
137 | struct jpeg_decomp_master { | |
138 | JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo)); | |
139 | JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo)); | |
140 | ||
141 | /* State variables made visible to other modules */ | |
142 | boolean is_dummy_pass; /* True during 1st pass for 2-pass quant */ | |
143 | }; | |
144 | ||
145 | /* Input control module */ | |
146 | struct jpeg_input_controller { | |
147 | JMETHOD(int, consume_input, (j_decompress_ptr cinfo)); | |
148 | JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo)); | |
149 | JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); | |
150 | JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo)); | |
151 | ||
152 | /* State variables made visible to other modules */ | |
153 | boolean has_multiple_scans; /* True if file has multiple scans */ | |
154 | boolean eoi_reached; /* True when EOI has been consumed */ | |
155 | }; | |
156 | ||
157 | /* Main buffer control (downsampled-data buffer) */ | |
158 | struct jpeg_d_main_controller { | |
159 | JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); | |
160 | JMETHOD(void, process_data, (j_decompress_ptr cinfo, | |
161 | JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, | |
162 | JDIMENSION out_rows_avail)); | |
163 | }; | |
164 | ||
165 | /* Coefficient buffer control */ | |
166 | struct jpeg_d_coef_controller { | |
167 | JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); | |
168 | JMETHOD(int, consume_data, (j_decompress_ptr cinfo)); | |
169 | JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo)); | |
170 | JMETHOD(int, decompress_data, (j_decompress_ptr cinfo, | |
171 | JSAMPIMAGE output_buf)); | |
172 | /* Pointer to array of coefficient virtual arrays, or NULL if none */ | |
173 | jvirt_barray_ptr *coef_arrays; | |
174 | }; | |
175 | ||
176 | /* Decompression postprocessing (color quantization buffer control) */ | |
177 | struct jpeg_d_post_controller { | |
178 | JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); | |
179 | JMETHOD(void, post_process_data, (j_decompress_ptr cinfo, | |
180 | JSAMPIMAGE input_buf, | |
181 | JDIMENSION *in_row_group_ctr, | |
182 | JDIMENSION in_row_groups_avail, | |
183 | JSAMPARRAY output_buf, | |
184 | JDIMENSION *out_row_ctr, | |
185 | JDIMENSION out_rows_avail)); | |
186 | }; | |
187 | ||
188 | /* Marker reading & parsing */ | |
189 | struct jpeg_marker_reader { | |
190 | JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo)); | |
191 | /* Read markers until SOS or EOI. | |
192 | * Returns same codes as are defined for jpeg_consume_input: | |
193 | * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. | |
194 | */ | |
195 | JMETHOD(int, read_markers, (j_decompress_ptr cinfo)); | |
196 | /* Read a restart marker --- exported for use by entropy decoder only */ | |
197 | jpeg_marker_parser_method read_restart_marker; | |
198 | ||
199 | /* State of marker reader --- nominally internal, but applications | |
200 | * supplying COM or APPn handlers might like to know the state. | |
201 | */ | |
202 | boolean saw_SOI; /* found SOI? */ | |
203 | boolean saw_SOF; /* found SOF? */ | |
204 | int next_restart_num; /* next restart number expected (0-7) */ | |
205 | unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */ | |
206 | }; | |
207 | ||
208 | /* Entropy decoding */ | |
209 | struct jpeg_entropy_decoder { | |
210 | JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); | |
211 | JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo, | |
212 | JBLOCKROW *MCU_data)); | |
213 | ||
214 | /* This is here to share code between baseline and progressive decoders; */ | |
215 | /* other modules probably should not use it */ | |
216 | boolean insufficient_data; /* set TRUE after emitting warning */ | |
217 | }; | |
218 | ||
219 | /* Inverse DCT (also performs dequantization) */ | |
220 | typedef JMETHOD(void, inverse_DCT_method_ptr, | |
221 | (j_decompress_ptr cinfo, jpeg_component_info * compptr, | |
222 | JCOEFPTR coef_block, | |
223 | JSAMPARRAY output_buf, JDIMENSION output_col)); | |
224 | ||
225 | struct jpeg_inverse_dct { | |
226 | JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); | |
227 | /* It is useful to allow each component to have a separate IDCT method. */ | |
228 | inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS]; | |
229 | }; | |
230 | ||
231 | /* Upsampling (note that upsampler must also call color converter) */ | |
232 | struct jpeg_upsampler { | |
233 | JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); | |
234 | JMETHOD(void, upsample, (j_decompress_ptr cinfo, | |
235 | JSAMPIMAGE input_buf, | |
236 | JDIMENSION *in_row_group_ctr, | |
237 | JDIMENSION in_row_groups_avail, | |
238 | JSAMPARRAY output_buf, | |
239 | JDIMENSION *out_row_ctr, | |
240 | JDIMENSION out_rows_avail)); | |
241 | ||
242 | boolean need_context_rows; /* TRUE if need rows above & below */ | |
243 | }; | |
244 | ||
245 | /* Colorspace conversion */ | |
246 | struct jpeg_color_deconverter { | |
247 | JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); | |
248 | JMETHOD(void, color_convert, (j_decompress_ptr cinfo, | |
249 | JSAMPIMAGE input_buf, JDIMENSION input_row, | |
250 | JSAMPARRAY output_buf, int num_rows)); | |
251 | }; | |
252 | ||
253 | /* Color quantization or color precision reduction */ | |
254 | struct jpeg_color_quantizer { | |
255 | JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan)); | |
256 | JMETHOD(void, color_quantize, (j_decompress_ptr cinfo, | |
257 | JSAMPARRAY input_buf, JSAMPARRAY output_buf, | |
258 | int num_rows)); | |
259 | JMETHOD(void, finish_pass, (j_decompress_ptr cinfo)); | |
260 | JMETHOD(void, new_color_map, (j_decompress_ptr cinfo)); | |
261 | }; | |
262 | ||
263 | ||
264 | /* Miscellaneous useful macros */ | |
265 | ||
266 | #undef MAX | |
267 | #define MAX(a,b) ((a) > (b) ? (a) : (b)) | |
268 | #undef MIN | |
269 | #define MIN(a,b) ((a) < (b) ? (a) : (b)) | |
270 | ||
271 | ||
272 | /* We assume that right shift corresponds to signed division by 2 with | |
273 | * rounding towards minus infinity. This is correct for typical "arithmetic | |
274 | * shift" instructions that shift in copies of the sign bit. But some | |
275 | * C compilers implement >> with an unsigned shift. For these machines you | |
276 | * must define RIGHT_SHIFT_IS_UNSIGNED. | |
277 | * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity. | |
278 | * It is only applied with constant shift counts. SHIFT_TEMPS must be | |
279 | * included in the variables of any routine using RIGHT_SHIFT. | |
280 | */ | |
281 | ||
282 | #ifdef RIGHT_SHIFT_IS_UNSIGNED | |
283 | #define SHIFT_TEMPS JPEG_INT32 shift_temp; | |
284 | #define RIGHT_SHIFT(x,shft) \ | |
285 | ((shift_temp = (x)) < 0 ? \ | |
286 | (shift_temp >> (shft)) | ((~((JPEG_INT32) 0)) << (32-(shft))) : \ | |
287 | (shift_temp >> (shft))) | |
288 | #else | |
289 | #define SHIFT_TEMPS | |
290 | #define RIGHT_SHIFT(x,shft) ((x) >> (shft)) | |
291 | #endif | |
292 | ||
293 | ||
294 | /* Short forms of external names for systems with brain-damaged linkers. */ | |
295 | ||
296 | #ifdef NEED_SHORT_EXTERNAL_NAMES | |
297 | #define jinit_compress_master jICompress | |
298 | #define jinit_c_master_control jICMaster | |
299 | #define jinit_c_main_controller jICMainC | |
300 | #define jinit_c_prep_controller jICPrepC | |
301 | #define jinit_c_coef_controller jICCoefC | |
302 | #define jinit_color_converter jICColor | |
303 | #define jinit_downsampler jIDownsampler | |
304 | #define jinit_forward_dct jIFDCT | |
305 | #define jinit_huff_encoder jIHEncoder | |
306 | #define jinit_phuff_encoder jIPHEncoder | |
307 | #define jinit_marker_writer jIMWriter | |
308 | #define jinit_master_decompress jIDMaster | |
309 | #define jinit_d_main_controller jIDMainC | |
310 | #define jinit_d_coef_controller jIDCoefC | |
311 | #define jinit_d_post_controller jIDPostC | |
312 | #define jinit_input_controller jIInCtlr | |
313 | #define jinit_marker_reader jIMReader | |
314 | #define jinit_huff_decoder jIHDecoder | |
315 | #define jinit_phuff_decoder jIPHDecoder | |
316 | #define jinit_inverse_dct jIIDCT | |
317 | #define jinit_upsampler jIUpsampler | |
318 | #define jinit_color_deconverter jIDColor | |
319 | #define jinit_1pass_quantizer jI1Quant | |
320 | #define jinit_2pass_quantizer jI2Quant | |
321 | #define jinit_merged_upsampler jIMUpsampler | |
322 | #define jinit_memory_mgr jIMemMgr | |
323 | #define jdiv_round_up jDivRound | |
324 | #define jround_up jRound | |
325 | #define jcopy_sample_rows jCopySamples | |
326 | #define jcopy_block_row jCopyBlocks | |
327 | #define jzero_far jZeroFar | |
328 | #define jpeg_zigzag_order jZIGTable | |
329 | #define jpeg_natural_order jZAGTable | |
330 | #endif /* NEED_SHORT_EXTERNAL_NAMES */ | |
331 | ||
332 | ||
333 | /* Compression module initialization routines */ | |
334 | EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo)); | |
335 | EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo, | |
336 | boolean transcode_only)); | |
337 | EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo, | |
338 | boolean need_full_buffer)); | |
339 | EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo, | |
340 | boolean need_full_buffer)); | |
341 | EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo, | |
342 | boolean need_full_buffer)); | |
343 | EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo)); | |
344 | EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo)); | |
345 | EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo)); | |
346 | EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo)); | |
347 | EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo)); | |
348 | EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo)); | |
349 | /* Decompression module initialization routines */ | |
350 | EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo)); | |
351 | EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo, | |
352 | boolean need_full_buffer)); | |
353 | EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo, | |
354 | boolean need_full_buffer)); | |
355 | EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo, | |
356 | boolean need_full_buffer)); | |
357 | EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo)); | |
358 | EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo)); | |
359 | EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo)); | |
360 | EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo)); | |
361 | EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo)); | |
362 | EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo)); | |
363 | EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo)); | |
364 | EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo)); | |
365 | EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo)); | |
366 | EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo)); | |
367 | /* Memory manager initialization */ | |
368 | EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo)); | |
369 | ||
370 | /* Utility routines in jutils.c */ | |
371 | EXTERN(long) jdiv_round_up JPP((long a, long b)); | |
372 | EXTERN(long) jround_up JPP((long a, long b)); | |
373 | EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row, | |
374 | JSAMPARRAY output_array, int dest_row, | |
375 | int num_rows, JDIMENSION num_cols)); | |
376 | EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row, | |
377 | JDIMENSION num_blocks)); | |
378 | EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero)); | |
379 | /* Constant tables in jutils.c */ | |
380 | #if 0 /* This table is not actually needed in v6a */ | |
381 | extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */ | |
382 | #endif | |
383 | extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */ | |
384 | ||
385 | /* Suppress undefined-structure complaints if necessary. */ | |
386 | ||
387 | #ifdef INCOMPLETE_TYPES_BROKEN | |
388 | #ifndef AM_MEMORY_MANAGER /* only jmemmgr.c defines these */ | |
389 | struct jvirt_sarray_control { long dummy; }; | |
390 | struct jvirt_barray_control { long dummy; }; | |
391 | #endif | |
392 | #endif /* INCOMPLETE_TYPES_BROKEN */ |