/[pcsx2_0.9.7]/trunk/3rdparty/libjpeg/jcmaster.c
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Contents of /trunk/3rdparty/libjpeg/jcmaster.c

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Revision 31 - (show annotations) (download)
Tue Sep 7 03:24:11 2010 UTC (9 years, 11 months ago) by william
File MIME type: text/plain
File size: 27448 byte(s)
committing r3113 initial commit again...
1 /*
2 * jcmaster.c
3 *
4 * Copyright (C) 1991-1997, Thomas G. Lane.
5 * Modified 2003-2009 by Guido Vollbeding.
6 * This file is part of the Independent JPEG Group's software.
7 * For conditions of distribution and use, see the accompanying README file.
8 *
9 * This file contains master control logic for the JPEG compressor.
10 * These routines are concerned with parameter validation, initial setup,
11 * and inter-pass control (determining the number of passes and the work
12 * to be done in each pass).
13 */
14
15 #define JPEG_INTERNALS
16 #include "jinclude.h"
17 #include "jpeglib.h"
18
19
20 /* Private state */
21
22 typedef enum {
23 main_pass, /* input data, also do first output step */
24 huff_opt_pass, /* Huffman code optimization pass */
25 output_pass /* data output pass */
26 } c_pass_type;
27
28 typedef struct {
29 struct jpeg_comp_master pub; /* public fields */
30
31 c_pass_type pass_type; /* the type of the current pass */
32
33 int pass_number; /* # of passes completed */
34 int total_passes; /* total # of passes needed */
35
36 int scan_number; /* current index in scan_info[] */
37 } my_comp_master;
38
39 typedef my_comp_master * my_master_ptr;
40
41
42 /*
43 * Support routines that do various essential calculations.
44 */
45
46 /*
47 * Compute JPEG image dimensions and related values.
48 * NOTE: this is exported for possible use by application.
49 * Hence it mustn't do anything that can't be done twice.
50 */
51
52 GLOBAL(void)
53 jpeg_calc_jpeg_dimensions (j_compress_ptr cinfo)
54 /* Do computations that are needed before master selection phase */
55 {
56 #ifdef DCT_SCALING_SUPPORTED
57
58 /* Compute actual JPEG image dimensions and DCT scaling choices. */
59 if (cinfo->scale_num >= cinfo->scale_denom * 8) {
60 /* Provide 8/1 scaling */
61 cinfo->jpeg_width = cinfo->image_width << 3;
62 cinfo->jpeg_height = cinfo->image_height << 3;
63 cinfo->min_DCT_h_scaled_size = 1;
64 cinfo->min_DCT_v_scaled_size = 1;
65 } else if (cinfo->scale_num >= cinfo->scale_denom * 4) {
66 /* Provide 4/1 scaling */
67 cinfo->jpeg_width = cinfo->image_width << 2;
68 cinfo->jpeg_height = cinfo->image_height << 2;
69 cinfo->min_DCT_h_scaled_size = 2;
70 cinfo->min_DCT_v_scaled_size = 2;
71 } else if (cinfo->scale_num * 3 >= cinfo->scale_denom * 8) {
72 /* Provide 8/3 scaling */
73 cinfo->jpeg_width = (cinfo->image_width << 1) + (JDIMENSION)
74 jdiv_round_up((long) cinfo->image_width * 2, 3L);
75 cinfo->jpeg_height = (cinfo->image_height << 1) + (JDIMENSION)
76 jdiv_round_up((long) cinfo->image_height * 2, 3L);
77 cinfo->min_DCT_h_scaled_size = 3;
78 cinfo->min_DCT_v_scaled_size = 3;
79 } else if (cinfo->scale_num >= cinfo->scale_denom * 2) {
80 /* Provide 2/1 scaling */
81 cinfo->jpeg_width = cinfo->image_width << 1;
82 cinfo->jpeg_height = cinfo->image_height << 1;
83 cinfo->min_DCT_h_scaled_size = 4;
84 cinfo->min_DCT_v_scaled_size = 4;
85 } else if (cinfo->scale_num * 5 >= cinfo->scale_denom * 8) {
86 /* Provide 8/5 scaling */
87 cinfo->jpeg_width = cinfo->image_width + (JDIMENSION)
88 jdiv_round_up((long) cinfo->image_width * 3, 5L);
89 cinfo->jpeg_height = cinfo->image_height + (JDIMENSION)
90 jdiv_round_up((long) cinfo->image_height * 3, 5L);
91 cinfo->min_DCT_h_scaled_size = 5;
92 cinfo->min_DCT_v_scaled_size = 5;
93 } else if (cinfo->scale_num * 3 >= cinfo->scale_denom * 4) {
94 /* Provide 4/3 scaling */
95 cinfo->jpeg_width = cinfo->image_width + (JDIMENSION)
96 jdiv_round_up((long) cinfo->image_width, 3L);
97 cinfo->jpeg_height = cinfo->image_height + (JDIMENSION)
98 jdiv_round_up((long) cinfo->image_height, 3L);
99 cinfo->min_DCT_h_scaled_size = 6;
100 cinfo->min_DCT_v_scaled_size = 6;
101 } else if (cinfo->scale_num * 7 >= cinfo->scale_denom * 8) {
102 /* Provide 8/7 scaling */
103 cinfo->jpeg_width = cinfo->image_width + (JDIMENSION)
104 jdiv_round_up((long) cinfo->image_width, 7L);
105 cinfo->jpeg_height = cinfo->image_height + (JDIMENSION)
106 jdiv_round_up((long) cinfo->image_height, 7L);
107 cinfo->min_DCT_h_scaled_size = 7;
108 cinfo->min_DCT_v_scaled_size = 7;
109 } else if (cinfo->scale_num >= cinfo->scale_denom) {
110 /* Provide 1/1 scaling */
111 cinfo->jpeg_width = cinfo->image_width;
112 cinfo->jpeg_height = cinfo->image_height;
113 cinfo->min_DCT_h_scaled_size = DCTSIZE;
114 cinfo->min_DCT_v_scaled_size = DCTSIZE;
115 } else if (cinfo->scale_num * 9 >= cinfo->scale_denom * 8) {
116 /* Provide 8/9 scaling */
117 cinfo->jpeg_width = (JDIMENSION)
118 jdiv_round_up((long) cinfo->image_width * 8, 9L);
119 cinfo->jpeg_height = (JDIMENSION)
120 jdiv_round_up((long) cinfo->image_height * 8, 9L);
121 cinfo->min_DCT_h_scaled_size = 9;
122 cinfo->min_DCT_v_scaled_size = 9;
123 } else if (cinfo->scale_num * 5 >= cinfo->scale_denom * 4) {
124 /* Provide 4/5 scaling */
125 cinfo->jpeg_width = (JDIMENSION)
126 jdiv_round_up((long) cinfo->image_width * 4, 5L);
127 cinfo->jpeg_height = (JDIMENSION)
128 jdiv_round_up((long) cinfo->image_height * 4, 5L);
129 cinfo->min_DCT_h_scaled_size = 10;
130 cinfo->min_DCT_v_scaled_size = 10;
131 } else if (cinfo->scale_num * 11 >= cinfo->scale_denom * 8) {
132 /* Provide 8/11 scaling */
133 cinfo->jpeg_width = (JDIMENSION)
134 jdiv_round_up((long) cinfo->image_width * 8, 11L);
135 cinfo->jpeg_height = (JDIMENSION)
136 jdiv_round_up((long) cinfo->image_height * 8, 11L);
137 cinfo->min_DCT_h_scaled_size = 11;
138 cinfo->min_DCT_v_scaled_size = 11;
139 } else if (cinfo->scale_num * 3 >= cinfo->scale_denom * 2) {
140 /* Provide 2/3 scaling */
141 cinfo->jpeg_width = (JDIMENSION)
142 jdiv_round_up((long) cinfo->image_width * 2, 3L);
143 cinfo->jpeg_height = (JDIMENSION)
144 jdiv_round_up((long) cinfo->image_height * 2, 3L);
145 cinfo->min_DCT_h_scaled_size = 12;
146 cinfo->min_DCT_v_scaled_size = 12;
147 } else if (cinfo->scale_num * 13 >= cinfo->scale_denom * 8) {
148 /* Provide 8/13 scaling */
149 cinfo->jpeg_width = (JDIMENSION)
150 jdiv_round_up((long) cinfo->image_width * 8, 13L);
151 cinfo->jpeg_height = (JDIMENSION)
152 jdiv_round_up((long) cinfo->image_height * 8, 13L);
153 cinfo->min_DCT_h_scaled_size = 13;
154 cinfo->min_DCT_v_scaled_size = 13;
155 } else if (cinfo->scale_num * 7 >= cinfo->scale_denom * 4) {
156 /* Provide 4/7 scaling */
157 cinfo->jpeg_width = (JDIMENSION)
158 jdiv_round_up((long) cinfo->image_width * 4, 7L);
159 cinfo->jpeg_height = (JDIMENSION)
160 jdiv_round_up((long) cinfo->image_height * 4, 7L);
161 cinfo->min_DCT_h_scaled_size = 14;
162 cinfo->min_DCT_v_scaled_size = 14;
163 } else if (cinfo->scale_num * 15 >= cinfo->scale_denom * 8) {
164 /* Provide 8/15 scaling */
165 cinfo->jpeg_width = (JDIMENSION)
166 jdiv_round_up((long) cinfo->image_width * 8, 15L);
167 cinfo->jpeg_height = (JDIMENSION)
168 jdiv_round_up((long) cinfo->image_height * 8, 15L);
169 cinfo->min_DCT_h_scaled_size = 15;
170 cinfo->min_DCT_v_scaled_size = 15;
171 } else {
172 /* Provide 1/2 scaling */
173 cinfo->jpeg_width = (JDIMENSION)
174 jdiv_round_up((long) cinfo->image_width, 2L);
175 cinfo->jpeg_height = (JDIMENSION)
176 jdiv_round_up((long) cinfo->image_height, 2L);
177 cinfo->min_DCT_h_scaled_size = 16;
178 cinfo->min_DCT_v_scaled_size = 16;
179 }
180
181 #else /* !DCT_SCALING_SUPPORTED */
182
183 /* Hardwire it to "no scaling" */
184 cinfo->jpeg_width = cinfo->image_width;
185 cinfo->jpeg_height = cinfo->image_height;
186 cinfo->min_DCT_h_scaled_size = DCTSIZE;
187 cinfo->min_DCT_v_scaled_size = DCTSIZE;
188
189 #endif /* DCT_SCALING_SUPPORTED */
190 }
191
192
193 LOCAL(void)
194 initial_setup (j_compress_ptr cinfo)
195 /* Do computations that are needed before master selection phase */
196 {
197 int ci, ssize;
198 jpeg_component_info *compptr;
199 long samplesperrow;
200 JDIMENSION jd_samplesperrow;
201
202 jpeg_calc_jpeg_dimensions(cinfo);
203
204 /* Sanity check on image dimensions */
205 if (cinfo->jpeg_height <= 0 || cinfo->jpeg_width <= 0
206 || cinfo->num_components <= 0 || cinfo->input_components <= 0)
207 ERREXIT(cinfo, JERR_EMPTY_IMAGE);
208
209 /* Make sure image isn't bigger than I can handle */
210 if ((long) cinfo->jpeg_height > (long) JPEG_MAX_DIMENSION ||
211 (long) cinfo->jpeg_width > (long) JPEG_MAX_DIMENSION)
212 ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
213
214 /* Width of an input scanline must be representable as JDIMENSION. */
215 samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
216 jd_samplesperrow = (JDIMENSION) samplesperrow;
217 if ((long) jd_samplesperrow != samplesperrow)
218 ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
219
220 /* For now, precision must match compiled-in value... */
221 if (cinfo->data_precision != BITS_IN_JSAMPLE)
222 ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
223
224 /* Check that number of components won't exceed internal array sizes */
225 if (cinfo->num_components > MAX_COMPONENTS)
226 ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
227 MAX_COMPONENTS);
228
229 /* Compute maximum sampling factors; check factor validity */
230 cinfo->max_h_samp_factor = 1;
231 cinfo->max_v_samp_factor = 1;
232 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
233 ci++, compptr++) {
234 if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
235 compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
236 ERREXIT(cinfo, JERR_BAD_SAMPLING);
237 cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
238 compptr->h_samp_factor);
239 cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
240 compptr->v_samp_factor);
241 }
242
243 /* Compute dimensions of components */
244 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
245 ci++, compptr++) {
246 /* Fill in the correct component_index value; don't rely on application */
247 compptr->component_index = ci;
248 /* In selecting the actual DCT scaling for each component, we try to
249 * scale down the chroma components via DCT scaling rather than downsampling.
250 * This saves time if the downsampler gets to use 1:1 scaling.
251 * Note this code adapts subsampling ratios which are powers of 2.
252 */
253 ssize = 1;
254 #ifdef DCT_SCALING_SUPPORTED
255 while (cinfo->min_DCT_h_scaled_size * ssize <=
256 (cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
257 (cinfo->max_h_samp_factor % (compptr->h_samp_factor * ssize * 2)) == 0) {
258 ssize = ssize * 2;
259 }
260 #endif
261 compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size * ssize;
262 ssize = 1;
263 #ifdef DCT_SCALING_SUPPORTED
264 while (cinfo->min_DCT_v_scaled_size * ssize <=
265 (cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
266 (cinfo->max_v_samp_factor % (compptr->v_samp_factor * ssize * 2)) == 0) {
267 ssize = ssize * 2;
268 }
269 #endif
270 compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size * ssize;
271
272 /* We don't support DCT ratios larger than 2. */
273 if (compptr->DCT_h_scaled_size > compptr->DCT_v_scaled_size * 2)
274 compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size * 2;
275 else if (compptr->DCT_v_scaled_size > compptr->DCT_h_scaled_size * 2)
276 compptr->DCT_v_scaled_size = compptr->DCT_h_scaled_size * 2;
277
278 /* Size in DCT blocks */
279 compptr->width_in_blocks = (JDIMENSION)
280 jdiv_round_up((long) cinfo->jpeg_width * (long) compptr->h_samp_factor,
281 (long) (cinfo->max_h_samp_factor * DCTSIZE));
282 compptr->height_in_blocks = (JDIMENSION)
283 jdiv_round_up((long) cinfo->jpeg_height * (long) compptr->v_samp_factor,
284 (long) (cinfo->max_v_samp_factor * DCTSIZE));
285 /* Size in samples */
286 compptr->downsampled_width = (JDIMENSION)
287 jdiv_round_up((long) cinfo->jpeg_width *
288 (long) (compptr->h_samp_factor * compptr->DCT_h_scaled_size),
289 (long) (cinfo->max_h_samp_factor * DCTSIZE));
290 compptr->downsampled_height = (JDIMENSION)
291 jdiv_round_up((long) cinfo->jpeg_height *
292 (long) (compptr->v_samp_factor * compptr->DCT_v_scaled_size),
293 (long) (cinfo->max_v_samp_factor * DCTSIZE));
294 /* Mark component needed (this flag isn't actually used for compression) */
295 compptr->component_needed = TRUE;
296 }
297
298 /* Compute number of fully interleaved MCU rows (number of times that
299 * main controller will call coefficient controller).
300 */
301 cinfo->total_iMCU_rows = (JDIMENSION)
302 jdiv_round_up((long) cinfo->jpeg_height,
303 (long) (cinfo->max_v_samp_factor*DCTSIZE));
304 }
305
306
307 #ifdef C_MULTISCAN_FILES_SUPPORTED
308
309 LOCAL(void)
310 validate_script (j_compress_ptr cinfo)
311 /* Verify that the scan script in cinfo->scan_info[] is valid; also
312 * determine whether it uses progressive JPEG, and set cinfo->progressive_mode.
313 */
314 {
315 const jpeg_scan_info * scanptr;
316 int scanno, ncomps, ci, coefi, thisi;
317 int Ss, Se, Ah, Al;
318 boolean component_sent[MAX_COMPONENTS];
319 #ifdef C_PROGRESSIVE_SUPPORTED
320 int * last_bitpos_ptr;
321 int last_bitpos[MAX_COMPONENTS][DCTSIZE2];
322 /* -1 until that coefficient has been seen; then last Al for it */
323 #endif
324
325 if (cinfo->num_scans <= 0)
326 ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);
327
328 /* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
329 * for progressive JPEG, no scan can have this.
330 */
331 scanptr = cinfo->scan_info;
332 if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) {
333 #ifdef C_PROGRESSIVE_SUPPORTED
334 cinfo->progressive_mode = TRUE;
335 last_bitpos_ptr = & last_bitpos[0][0];
336 for (ci = 0; ci < cinfo->num_components; ci++)
337 for (coefi = 0; coefi < DCTSIZE2; coefi++)
338 *last_bitpos_ptr++ = -1;
339 #else
340 ERREXIT(cinfo, JERR_NOT_COMPILED);
341 #endif
342 } else {
343 cinfo->progressive_mode = FALSE;
344 for (ci = 0; ci < cinfo->num_components; ci++)
345 component_sent[ci] = FALSE;
346 }
347
348 for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {
349 /* Validate component indexes */
350 ncomps = scanptr->comps_in_scan;
351 if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)
352 ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
353 for (ci = 0; ci < ncomps; ci++) {
354 thisi = scanptr->component_index[ci];
355 if (thisi < 0 || thisi >= cinfo->num_components)
356 ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
357 /* Components must appear in SOF order within each scan */
358 if (ci > 0 && thisi <= scanptr->component_index[ci-1])
359 ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
360 }
361 /* Validate progression parameters */
362 Ss = scanptr->Ss;
363 Se = scanptr->Se;
364 Ah = scanptr->Ah;
365 Al = scanptr->Al;
366 if (cinfo->progressive_mode) {
367 #ifdef C_PROGRESSIVE_SUPPORTED
368 /* The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that
369 * seems wrong: the upper bound ought to depend on data precision.
370 * Perhaps they really meant 0..N+1 for N-bit precision.
371 * Here we allow 0..10 for 8-bit data; Al larger than 10 results in
372 * out-of-range reconstructed DC values during the first DC scan,
373 * which might cause problems for some decoders.
374 */
375 #if BITS_IN_JSAMPLE == 8
376 #define MAX_AH_AL 10
377 #else
378 #define MAX_AH_AL 13
379 #endif
380 if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||
381 Ah < 0 || Ah > MAX_AH_AL || Al < 0 || Al > MAX_AH_AL)
382 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
383 if (Ss == 0) {
384 if (Se != 0) /* DC and AC together not OK */
385 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
386 } else {
387 if (ncomps != 1) /* AC scans must be for only one component */
388 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
389 }
390 for (ci = 0; ci < ncomps; ci++) {
391 last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0];
392 if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */
393 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
394 for (coefi = Ss; coefi <= Se; coefi++) {
395 if (last_bitpos_ptr[coefi] < 0) {
396 /* first scan of this coefficient */
397 if (Ah != 0)
398 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
399 } else {
400 /* not first scan */
401 if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1)
402 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
403 }
404 last_bitpos_ptr[coefi] = Al;
405 }
406 }
407 #endif
408 } else {
409 /* For sequential JPEG, all progression parameters must be these: */
410 if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0)
411 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
412 /* Make sure components are not sent twice */
413 for (ci = 0; ci < ncomps; ci++) {
414 thisi = scanptr->component_index[ci];
415 if (component_sent[thisi])
416 ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
417 component_sent[thisi] = TRUE;
418 }
419 }
420 }
421
422 /* Now verify that everything got sent. */
423 if (cinfo->progressive_mode) {
424 #ifdef C_PROGRESSIVE_SUPPORTED
425 /* For progressive mode, we only check that at least some DC data
426 * got sent for each component; the spec does not require that all bits
427 * of all coefficients be transmitted. Would it be wiser to enforce
428 * transmission of all coefficient bits??
429 */
430 for (ci = 0; ci < cinfo->num_components; ci++) {
431 if (last_bitpos[ci][0] < 0)
432 ERREXIT(cinfo, JERR_MISSING_DATA);
433 }
434 #endif
435 } else {
436 for (ci = 0; ci < cinfo->num_components; ci++) {
437 if (! component_sent[ci])
438 ERREXIT(cinfo, JERR_MISSING_DATA);
439 }
440 }
441 }
442
443 #endif /* C_MULTISCAN_FILES_SUPPORTED */
444
445
446 LOCAL(void)
447 select_scan_parameters (j_compress_ptr cinfo)
448 /* Set up the scan parameters for the current scan */
449 {
450 int ci;
451
452 #ifdef C_MULTISCAN_FILES_SUPPORTED
453 if (cinfo->scan_info != NULL) {
454 /* Prepare for current scan --- the script is already validated */
455 my_master_ptr master = (my_master_ptr) cinfo->master;
456 const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number;
457
458 cinfo->comps_in_scan = scanptr->comps_in_scan;
459 for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
460 cinfo->cur_comp_info[ci] =
461 &cinfo->comp_info[scanptr->component_index[ci]];
462 }
463 cinfo->Ss = scanptr->Ss;
464 cinfo->Se = scanptr->Se;
465 cinfo->Ah = scanptr->Ah;
466 cinfo->Al = scanptr->Al;
467 }
468 else
469 #endif
470 {
471 /* Prepare for single sequential-JPEG scan containing all components */
472 if (cinfo->num_components > MAX_COMPS_IN_SCAN)
473 ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
474 MAX_COMPS_IN_SCAN);
475 cinfo->comps_in_scan = cinfo->num_components;
476 for (ci = 0; ci < cinfo->num_components; ci++) {
477 cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
478 }
479 cinfo->Ss = 0;
480 cinfo->Se = DCTSIZE2-1;
481 cinfo->Ah = 0;
482 cinfo->Al = 0;
483 }
484 }
485
486
487 LOCAL(void)
488 per_scan_setup (j_compress_ptr cinfo)
489 /* Do computations that are needed before processing a JPEG scan */
490 /* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
491 {
492 int ci, mcublks, tmp;
493 jpeg_component_info *compptr;
494
495 if (cinfo->comps_in_scan == 1) {
496
497 /* Noninterleaved (single-component) scan */
498 compptr = cinfo->cur_comp_info[0];
499
500 /* Overall image size in MCUs */
501 cinfo->MCUs_per_row = compptr->width_in_blocks;
502 cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
503
504 /* For noninterleaved scan, always one block per MCU */
505 compptr->MCU_width = 1;
506 compptr->MCU_height = 1;
507 compptr->MCU_blocks = 1;
508 compptr->MCU_sample_width = compptr->DCT_h_scaled_size;
509 compptr->last_col_width = 1;
510 /* For noninterleaved scans, it is convenient to define last_row_height
511 * as the number of block rows present in the last iMCU row.
512 */
513 tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
514 if (tmp == 0) tmp = compptr->v_samp_factor;
515 compptr->last_row_height = tmp;
516
517 /* Prepare array describing MCU composition */
518 cinfo->blocks_in_MCU = 1;
519 cinfo->MCU_membership[0] = 0;
520
521 } else {
522
523 /* Interleaved (multi-component) scan */
524 if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
525 ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
526 MAX_COMPS_IN_SCAN);
527
528 /* Overall image size in MCUs */
529 cinfo->MCUs_per_row = (JDIMENSION)
530 jdiv_round_up((long) cinfo->jpeg_width,
531 (long) (cinfo->max_h_samp_factor*DCTSIZE));
532 cinfo->MCU_rows_in_scan = (JDIMENSION)
533 jdiv_round_up((long) cinfo->jpeg_height,
534 (long) (cinfo->max_v_samp_factor*DCTSIZE));
535
536 cinfo->blocks_in_MCU = 0;
537
538 for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
539 compptr = cinfo->cur_comp_info[ci];
540 /* Sampling factors give # of blocks of component in each MCU */
541 compptr->MCU_width = compptr->h_samp_factor;
542 compptr->MCU_height = compptr->v_samp_factor;
543 compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
544 compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_h_scaled_size;
545 /* Figure number of non-dummy blocks in last MCU column & row */
546 tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
547 if (tmp == 0) tmp = compptr->MCU_width;
548 compptr->last_col_width = tmp;
549 tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
550 if (tmp == 0) tmp = compptr->MCU_height;
551 compptr->last_row_height = tmp;
552 /* Prepare array describing MCU composition */
553 mcublks = compptr->MCU_blocks;
554 if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)
555 ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
556 while (mcublks-- > 0) {
557 cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
558 }
559 }
560
561 }
562
563 /* Convert restart specified in rows to actual MCU count. */
564 /* Note that count must fit in 16 bits, so we provide limiting. */
565 if (cinfo->restart_in_rows > 0) {
566 long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;
567 cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);
568 }
569 }
570
571
572 /*
573 * Per-pass setup.
574 * This is called at the beginning of each pass. We determine which modules
575 * will be active during this pass and give them appropriate start_pass calls.
576 * We also set is_last_pass to indicate whether any more passes will be
577 * required.
578 */
579
580 METHODDEF(void)
581 prepare_for_pass (j_compress_ptr cinfo)
582 {
583 my_master_ptr master = (my_master_ptr) cinfo->master;
584
585 switch (master->pass_type) {
586 case main_pass:
587 /* Initial pass: will collect input data, and do either Huffman
588 * optimization or data output for the first scan.
589 */
590 select_scan_parameters(cinfo);
591 per_scan_setup(cinfo);
592 if (! cinfo->raw_data_in) {
593 (*cinfo->cconvert->start_pass) (cinfo);
594 (*cinfo->downsample->start_pass) (cinfo);
595 (*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);
596 }
597 (*cinfo->fdct->start_pass) (cinfo);
598 (*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);
599 (*cinfo->coef->start_pass) (cinfo,
600 (master->total_passes > 1 ?
601 JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
602 (*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
603 if (cinfo->optimize_coding) {
604 /* No immediate data output; postpone writing frame/scan headers */
605 master->pub.call_pass_startup = FALSE;
606 } else {
607 /* Will write frame/scan headers at first jpeg_write_scanlines call */
608 master->pub.call_pass_startup = TRUE;
609 }
610 break;
611 #ifdef ENTROPY_OPT_SUPPORTED
612 case huff_opt_pass:
613 /* Do Huffman optimization for a scan after the first one. */
614 select_scan_parameters(cinfo);
615 per_scan_setup(cinfo);
616 if (cinfo->Ss != 0 || cinfo->Ah == 0) {
617 (*cinfo->entropy->start_pass) (cinfo, TRUE);
618 (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
619 master->pub.call_pass_startup = FALSE;
620 break;
621 }
622 /* Special case: Huffman DC refinement scans need no Huffman table
623 * and therefore we can skip the optimization pass for them.
624 */
625 master->pass_type = output_pass;
626 master->pass_number++;
627 /*FALLTHROUGH*/
628 #endif
629 case output_pass:
630 /* Do a data-output pass. */
631 /* We need not repeat per-scan setup if prior optimization pass did it. */
632 if (! cinfo->optimize_coding) {
633 select_scan_parameters(cinfo);
634 per_scan_setup(cinfo);
635 }
636 (*cinfo->entropy->start_pass) (cinfo, FALSE);
637 (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
638 /* We emit frame/scan headers now */
639 if (master->scan_number == 0)
640 (*cinfo->marker->write_frame_header) (cinfo);
641 (*cinfo->marker->write_scan_header) (cinfo);
642 master->pub.call_pass_startup = FALSE;
643 break;
644 default:
645 ERREXIT(cinfo, JERR_NOT_COMPILED);
646 }
647
648 master->pub.is_last_pass = (master->pass_number == master->total_passes-1);
649
650 /* Set up progress monitor's pass info if present */
651 if (cinfo->progress != NULL) {
652 cinfo->progress->completed_passes = master->pass_number;
653 cinfo->progress->total_passes = master->total_passes;
654 }
655 }
656
657
658 /*
659 * Special start-of-pass hook.
660 * This is called by jpeg_write_scanlines if call_pass_startup is TRUE.
661 * In single-pass processing, we need this hook because we don't want to
662 * write frame/scan headers during jpeg_start_compress; we want to let the
663 * application write COM markers etc. between jpeg_start_compress and the
664 * jpeg_write_scanlines loop.
665 * In multi-pass processing, this routine is not used.
666 */
667
668 METHODDEF(void)
669 pass_startup (j_compress_ptr cinfo)
670 {
671 cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */
672
673 (*cinfo->marker->write_frame_header) (cinfo);
674 (*cinfo->marker->write_scan_header) (cinfo);
675 }
676
677
678 /*
679 * Finish up at end of pass.
680 */
681
682 METHODDEF(void)
683 finish_pass_master (j_compress_ptr cinfo)
684 {
685 my_master_ptr master = (my_master_ptr) cinfo->master;
686
687 /* The entropy coder always needs an end-of-pass call,
688 * either to analyze statistics or to flush its output buffer.
689 */
690 (*cinfo->entropy->finish_pass) (cinfo);
691
692 /* Update state for next pass */
693 switch (master->pass_type) {
694 case main_pass:
695 /* next pass is either output of scan 0 (after optimization)
696 * or output of scan 1 (if no optimization).
697 */
698 master->pass_type = output_pass;
699 if (! cinfo->optimize_coding)
700 master->scan_number++;
701 break;
702 case huff_opt_pass:
703 /* next pass is always output of current scan */
704 master->pass_type = output_pass;
705 break;
706 case output_pass:
707 /* next pass is either optimization or output of next scan */
708 if (cinfo->optimize_coding)
709 master->pass_type = huff_opt_pass;
710 master->scan_number++;
711 break;
712 }
713
714 master->pass_number++;
715 }
716
717
718 /*
719 * Initialize master compression control.
720 */
721
722 GLOBAL(void)
723 jinit_c_master_control (j_compress_ptr cinfo, boolean transcode_only)
724 {
725 my_master_ptr master;
726
727 master = (my_master_ptr)
728 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
729 SIZEOF(my_comp_master));
730 cinfo->master = (struct jpeg_comp_master *) master;
731 master->pub.prepare_for_pass = prepare_for_pass;
732 master->pub.pass_startup = pass_startup;
733 master->pub.finish_pass = finish_pass_master;
734 master->pub.is_last_pass = FALSE;
735
736 /* Validate parameters, determine derived values */
737 initial_setup(cinfo);
738
739 if (cinfo->scan_info != NULL) {
740 #ifdef C_MULTISCAN_FILES_SUPPORTED
741 validate_script(cinfo);
742 #else
743 ERREXIT(cinfo, JERR_NOT_COMPILED);
744 #endif
745 } else {
746 cinfo->progressive_mode = FALSE;
747 cinfo->num_scans = 1;
748 }
749
750 if (cinfo->progressive_mode && cinfo->arith_code == 0) /* TEMPORARY HACK ??? */
751 cinfo->optimize_coding = TRUE; /* assume default tables no good for progressive mode */
752
753 /* Initialize my private state */
754 if (transcode_only) {
755 /* no main pass in transcoding */
756 if (cinfo->optimize_coding)
757 master->pass_type = huff_opt_pass;
758 else
759 master->pass_type = output_pass;
760 } else {
761 /* for normal compression, first pass is always this type: */
762 master->pass_type = main_pass;
763 }
764 master->scan_number = 0;
765 master->pass_number = 0;
766 if (cinfo->optimize_coding)
767 master->total_passes = cinfo->num_scans * 2;
768 else
769 master->total_passes = cinfo->num_scans;
770 }

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