1 /*
2 * jcmaster.c
3 *
4 * This file was part of the Independent JPEG Group's software:
5 * Copyright (C) 1991-1997, Thomas G. Lane.
6 * Modified 2003-2010 by Guido Vollbeding.
7 * libjpeg-turbo Modifications:
8 * Copyright (C) 2010, 2016, D. R. Commander.
9 * For conditions of distribution and use, see the accompanying README.ijg
10 * file.
11 *
12 * This file contains master control logic for the JPEG compressor.
13 * These routines are concerned with parameter validation, initial setup,
14 * and inter-pass control (determining the number of passes and the work
15 * to be done in each pass).
16 */
17
18 #define JPEG_INTERNALS
19 #include "jinclude.h"
20 #include "jpeglib.h"
21 #include "jpegcomp.h"
22 #include "jconfigint.h"
23
24
25 /* Private state */
26
27 typedef enum {
28 main_pass, /* input data, also do first output step */
29 huff_opt_pass, /* Huffman code optimization pass */
30 output_pass /* data output pass */
31 } c_pass_type;
32
33 typedef struct {
34 struct jpeg_comp_master pub; /* public fields */
35
36 c_pass_type pass_type; /* the type of the current pass */
37
38 int pass_number; /* # of passes completed */
39 int total_passes; /* total # of passes needed */
40
41 int scan_number; /* current index in scan_info[] */
42
43 /*
44 * This is here so we can add libjpeg-turbo version/build information to the
45 * global string table without introducing a new global symbol. Adding this
46 * information to the global string table allows one to examine a binary
47 * object and determine which version of libjpeg-turbo it was built from or
48 * linked against.
49 */
50 const char *jpeg_version;
51
52 } my_comp_master;
53
54 typedef my_comp_master *my_master_ptr;
55
56
57 /*
58 * Support routines that do various essential calculations.
59 */
60
61 #if JPEG_LIB_VERSION >= 70
62 /*
63 * Compute JPEG image dimensions and related values.
64 * NOTE: this is exported for possible use by application.
65 * Hence it mustn't do anything that can't be done twice.
66 */
67
68 GLOBAL(void)
jpeg_calc_jpeg_dimensions(j_compress_ptr cinfo)69 jpeg_calc_jpeg_dimensions (j_compress_ptr cinfo)
70 /* Do computations that are needed before master selection phase */
71 {
72 /* Hardwire it to "no scaling" */
73 cinfo->jpeg_width = cinfo->image_width;
74 cinfo->jpeg_height = cinfo->image_height;
75 cinfo->min_DCT_h_scaled_size = DCTSIZE;
76 cinfo->min_DCT_v_scaled_size = DCTSIZE;
77 }
78 #endif
79
80
81 LOCAL(void)
initial_setup(j_compress_ptr cinfo,boolean transcode_only)82 initial_setup (j_compress_ptr cinfo, boolean transcode_only)
83 /* Do computations that are needed before master selection phase */
84 {
85 int ci;
86 jpeg_component_info *compptr;
87 long samplesperrow;
88 JDIMENSION jd_samplesperrow;
89
90 #if JPEG_LIB_VERSION >= 70
91 #if JPEG_LIB_VERSION >= 80
92 if (!transcode_only)
93 #endif
94 jpeg_calc_jpeg_dimensions(cinfo);
95 #endif
96
97 /* Sanity check on image dimensions */
98 if (cinfo->_jpeg_height <= 0 || cinfo->_jpeg_width <= 0
99 || cinfo->num_components <= 0 || cinfo->input_components <= 0)
100 ERREXIT(cinfo, JERR_EMPTY_IMAGE);
101
102 /* Make sure image isn't bigger than I can handle */
103 if ((long) cinfo->_jpeg_height > (long) JPEG_MAX_DIMENSION ||
104 (long) cinfo->_jpeg_width > (long) JPEG_MAX_DIMENSION)
105 ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
106
107 /* Width of an input scanline must be representable as JDIMENSION. */
108 samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
109 jd_samplesperrow = (JDIMENSION) samplesperrow;
110 if ((long) jd_samplesperrow != samplesperrow)
111 ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
112
113 /* For now, precision must match compiled-in value... */
114 if (cinfo->data_precision != BITS_IN_JSAMPLE)
115 ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
116
117 /* Check that number of components won't exceed internal array sizes */
118 if (cinfo->num_components > MAX_COMPONENTS)
119 ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
120 MAX_COMPONENTS);
121
122 /* Compute maximum sampling factors; check factor validity */
123 cinfo->max_h_samp_factor = 1;
124 cinfo->max_v_samp_factor = 1;
125 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
126 ci++, compptr++) {
127 if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
128 compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
129 ERREXIT(cinfo, JERR_BAD_SAMPLING);
130 cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
131 compptr->h_samp_factor);
132 cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
133 compptr->v_samp_factor);
134 }
135
136 /* Compute dimensions of components */
137 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
138 ci++, compptr++) {
139 /* Fill in the correct component_index value; don't rely on application */
140 compptr->component_index = ci;
141 /* For compression, we never do DCT scaling. */
142 #if JPEG_LIB_VERSION >= 70
143 compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size = DCTSIZE;
144 #else
145 compptr->DCT_scaled_size = DCTSIZE;
146 #endif
147 /* Size in DCT blocks */
148 compptr->width_in_blocks = (JDIMENSION)
149 jdiv_round_up((long) cinfo->_jpeg_width * (long) compptr->h_samp_factor,
150 (long) (cinfo->max_h_samp_factor * DCTSIZE));
151 compptr->height_in_blocks = (JDIMENSION)
152 jdiv_round_up((long) cinfo->_jpeg_height * (long) compptr->v_samp_factor,
153 (long) (cinfo->max_v_samp_factor * DCTSIZE));
154 /* Size in samples */
155 compptr->downsampled_width = (JDIMENSION)
156 jdiv_round_up((long) cinfo->_jpeg_width * (long) compptr->h_samp_factor,
157 (long) cinfo->max_h_samp_factor);
158 compptr->downsampled_height = (JDIMENSION)
159 jdiv_round_up((long) cinfo->_jpeg_height * (long) compptr->v_samp_factor,
160 (long) cinfo->max_v_samp_factor);
161 /* Mark component needed (this flag isn't actually used for compression) */
162 compptr->component_needed = TRUE;
163 }
164
165 /* Compute number of fully interleaved MCU rows (number of times that
166 * main controller will call coefficient controller).
167 */
168 cinfo->total_iMCU_rows = (JDIMENSION)
169 jdiv_round_up((long) cinfo->_jpeg_height,
170 (long) (cinfo->max_v_samp_factor*DCTSIZE));
171 }
172
173
174 #ifdef C_MULTISCAN_FILES_SUPPORTED
175
176 LOCAL(void)
validate_script(j_compress_ptr cinfo)177 validate_script (j_compress_ptr cinfo)
178 /* Verify that the scan script in cinfo->scan_info[] is valid; also
179 * determine whether it uses progressive JPEG, and set cinfo->progressive_mode.
180 */
181 {
182 const jpeg_scan_info *scanptr;
183 int scanno, ncomps, ci, coefi, thisi;
184 int Ss, Se, Ah, Al;
185 boolean component_sent[MAX_COMPONENTS];
186 #ifdef C_PROGRESSIVE_SUPPORTED
187 int *last_bitpos_ptr;
188 int last_bitpos[MAX_COMPONENTS][DCTSIZE2];
189 /* -1 until that coefficient has been seen; then last Al for it */
190 #endif
191
192 if (cinfo->num_scans <= 0)
193 ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);
194
195 /* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
196 * for progressive JPEG, no scan can have this.
197 */
198 scanptr = cinfo->scan_info;
199 if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) {
200 #ifdef C_PROGRESSIVE_SUPPORTED
201 cinfo->progressive_mode = TRUE;
202 last_bitpos_ptr = & last_bitpos[0][0];
203 for (ci = 0; ci < cinfo->num_components; ci++)
204 for (coefi = 0; coefi < DCTSIZE2; coefi++)
205 *last_bitpos_ptr++ = -1;
206 #else
207 ERREXIT(cinfo, JERR_NOT_COMPILED);
208 #endif
209 } else {
210 cinfo->progressive_mode = FALSE;
211 for (ci = 0; ci < cinfo->num_components; ci++)
212 component_sent[ci] = FALSE;
213 }
214
215 for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {
216 /* Validate component indexes */
217 ncomps = scanptr->comps_in_scan;
218 if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)
219 ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
220 for (ci = 0; ci < ncomps; ci++) {
221 thisi = scanptr->component_index[ci];
222 if (thisi < 0 || thisi >= cinfo->num_components)
223 ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
224 /* Components must appear in SOF order within each scan */
225 if (ci > 0 && thisi <= scanptr->component_index[ci-1])
226 ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
227 }
228 /* Validate progression parameters */
229 Ss = scanptr->Ss;
230 Se = scanptr->Se;
231 Ah = scanptr->Ah;
232 Al = scanptr->Al;
233 if (cinfo->progressive_mode) {
234 #ifdef C_PROGRESSIVE_SUPPORTED
235 /* The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that
236 * seems wrong: the upper bound ought to depend on data precision.
237 * Perhaps they really meant 0..N+1 for N-bit precision.
238 * Here we allow 0..10 for 8-bit data; Al larger than 10 results in
239 * out-of-range reconstructed DC values during the first DC scan,
240 * which might cause problems for some decoders.
241 */
242 #if BITS_IN_JSAMPLE == 8
243 #define MAX_AH_AL 10
244 #else
245 #define MAX_AH_AL 13
246 #endif
247 if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||
248 Ah < 0 || Ah > MAX_AH_AL || Al < 0 || Al > MAX_AH_AL)
249 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
250 if (Ss == 0) {
251 if (Se != 0) /* DC and AC together not OK */
252 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
253 } else {
254 if (ncomps != 1) /* AC scans must be for only one component */
255 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
256 }
257 for (ci = 0; ci < ncomps; ci++) {
258 last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0];
259 if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */
260 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
261 for (coefi = Ss; coefi <= Se; coefi++) {
262 if (last_bitpos_ptr[coefi] < 0) {
263 /* first scan of this coefficient */
264 if (Ah != 0)
265 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
266 } else {
267 /* not first scan */
268 if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1)
269 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
270 }
271 last_bitpos_ptr[coefi] = Al;
272 }
273 }
274 #endif
275 } else {
276 /* For sequential JPEG, all progression parameters must be these: */
277 if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0)
278 ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
279 /* Make sure components are not sent twice */
280 for (ci = 0; ci < ncomps; ci++) {
281 thisi = scanptr->component_index[ci];
282 if (component_sent[thisi])
283 ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
284 component_sent[thisi] = TRUE;
285 }
286 }
287 }
288
289 /* Now verify that everything got sent. */
290 if (cinfo->progressive_mode) {
291 #ifdef C_PROGRESSIVE_SUPPORTED
292 /* For progressive mode, we only check that at least some DC data
293 * got sent for each component; the spec does not require that all bits
294 * of all coefficients be transmitted. Would it be wiser to enforce
295 * transmission of all coefficient bits??
296 */
297 for (ci = 0; ci < cinfo->num_components; ci++) {
298 if (last_bitpos[ci][0] < 0)
299 ERREXIT(cinfo, JERR_MISSING_DATA);
300 }
301 #endif
302 } else {
303 for (ci = 0; ci < cinfo->num_components; ci++) {
304 if (! component_sent[ci])
305 ERREXIT(cinfo, JERR_MISSING_DATA);
306 }
307 }
308 }
309
310 #endif /* C_MULTISCAN_FILES_SUPPORTED */
311
312
313 LOCAL(void)
select_scan_parameters(j_compress_ptr cinfo)314 select_scan_parameters (j_compress_ptr cinfo)
315 /* Set up the scan parameters for the current scan */
316 {
317 int ci;
318
319 #ifdef C_MULTISCAN_FILES_SUPPORTED
320 if (cinfo->scan_info != NULL) {
321 /* Prepare for current scan --- the script is already validated */
322 my_master_ptr master = (my_master_ptr) cinfo->master;
323 const jpeg_scan_info *scanptr = cinfo->scan_info + master->scan_number;
324
325 cinfo->comps_in_scan = scanptr->comps_in_scan;
326 for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
327 cinfo->cur_comp_info[ci] =
328 &cinfo->comp_info[scanptr->component_index[ci]];
329 }
330 cinfo->Ss = scanptr->Ss;
331 cinfo->Se = scanptr->Se;
332 cinfo->Ah = scanptr->Ah;
333 cinfo->Al = scanptr->Al;
334 }
335 else
336 #endif
337 {
338 /* Prepare for single sequential-JPEG scan containing all components */
339 if (cinfo->num_components > MAX_COMPS_IN_SCAN)
340 ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
341 MAX_COMPS_IN_SCAN);
342 cinfo->comps_in_scan = cinfo->num_components;
343 for (ci = 0; ci < cinfo->num_components; ci++) {
344 cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
345 }
346 cinfo->Ss = 0;
347 cinfo->Se = DCTSIZE2-1;
348 cinfo->Ah = 0;
349 cinfo->Al = 0;
350 }
351 }
352
353
354 LOCAL(void)
per_scan_setup(j_compress_ptr cinfo)355 per_scan_setup (j_compress_ptr cinfo)
356 /* Do computations that are needed before processing a JPEG scan */
357 /* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
358 {
359 int ci, mcublks, tmp;
360 jpeg_component_info *compptr;
361
362 if (cinfo->comps_in_scan == 1) {
363
364 /* Noninterleaved (single-component) scan */
365 compptr = cinfo->cur_comp_info[0];
366
367 /* Overall image size in MCUs */
368 cinfo->MCUs_per_row = compptr->width_in_blocks;
369 cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
370
371 /* For noninterleaved scan, always one block per MCU */
372 compptr->MCU_width = 1;
373 compptr->MCU_height = 1;
374 compptr->MCU_blocks = 1;
375 compptr->MCU_sample_width = DCTSIZE;
376 compptr->last_col_width = 1;
377 /* For noninterleaved scans, it is convenient to define last_row_height
378 * as the number of block rows present in the last iMCU row.
379 */
380 tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
381 if (tmp == 0) tmp = compptr->v_samp_factor;
382 compptr->last_row_height = tmp;
383
384 /* Prepare array describing MCU composition */
385 cinfo->blocks_in_MCU = 1;
386 cinfo->MCU_membership[0] = 0;
387
388 } else {
389
390 /* Interleaved (multi-component) scan */
391 if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
392 ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
393 MAX_COMPS_IN_SCAN);
394
395 /* Overall image size in MCUs */
396 cinfo->MCUs_per_row = (JDIMENSION)
397 jdiv_round_up((long) cinfo->_jpeg_width,
398 (long) (cinfo->max_h_samp_factor*DCTSIZE));
399 cinfo->MCU_rows_in_scan = (JDIMENSION)
400 jdiv_round_up((long) cinfo->_jpeg_height,
401 (long) (cinfo->max_v_samp_factor*DCTSIZE));
402
403 cinfo->blocks_in_MCU = 0;
404
405 for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
406 compptr = cinfo->cur_comp_info[ci];
407 /* Sampling factors give # of blocks of component in each MCU */
408 compptr->MCU_width = compptr->h_samp_factor;
409 compptr->MCU_height = compptr->v_samp_factor;
410 compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
411 compptr->MCU_sample_width = compptr->MCU_width * DCTSIZE;
412 /* Figure number of non-dummy blocks in last MCU column & row */
413 tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
414 if (tmp == 0) tmp = compptr->MCU_width;
415 compptr->last_col_width = tmp;
416 tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
417 if (tmp == 0) tmp = compptr->MCU_height;
418 compptr->last_row_height = tmp;
419 /* Prepare array describing MCU composition */
420 mcublks = compptr->MCU_blocks;
421 if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)
422 ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
423 while (mcublks-- > 0) {
424 cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
425 }
426 }
427
428 }
429
430 /* Convert restart specified in rows to actual MCU count. */
431 /* Note that count must fit in 16 bits, so we provide limiting. */
432 if (cinfo->restart_in_rows > 0) {
433 long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;
434 cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);
435 }
436 }
437
438
439 /*
440 * Per-pass setup.
441 * This is called at the beginning of each pass. We determine which modules
442 * will be active during this pass and give them appropriate start_pass calls.
443 * We also set is_last_pass to indicate whether any more passes will be
444 * required.
445 */
446
447 METHODDEF(void)
prepare_for_pass(j_compress_ptr cinfo)448 prepare_for_pass (j_compress_ptr cinfo)
449 {
450 my_master_ptr master = (my_master_ptr) cinfo->master;
451
452 switch (master->pass_type) {
453 case main_pass:
454 /* Initial pass: will collect input data, and do either Huffman
455 * optimization or data output for the first scan.
456 */
457 select_scan_parameters(cinfo);
458 per_scan_setup(cinfo);
459 if (! cinfo->raw_data_in) {
460 (*cinfo->cconvert->start_pass) (cinfo);
461 (*cinfo->downsample->start_pass) (cinfo);
462 (*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);
463 }
464 (*cinfo->fdct->start_pass) (cinfo);
465 (*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);
466 (*cinfo->coef->start_pass) (cinfo,
467 (master->total_passes > 1 ?
468 JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
469 (*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
470 if (cinfo->optimize_coding) {
471 /* No immediate data output; postpone writing frame/scan headers */
472 master->pub.call_pass_startup = FALSE;
473 } else {
474 /* Will write frame/scan headers at first jpeg_write_scanlines call */
475 master->pub.call_pass_startup = TRUE;
476 }
477 break;
478 #ifdef ENTROPY_OPT_SUPPORTED
479 case huff_opt_pass:
480 /* Do Huffman optimization for a scan after the first one. */
481 select_scan_parameters(cinfo);
482 per_scan_setup(cinfo);
483 if (cinfo->Ss != 0 || cinfo->Ah == 0 || cinfo->arith_code) {
484 (*cinfo->entropy->start_pass) (cinfo, TRUE);
485 (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
486 master->pub.call_pass_startup = FALSE;
487 break;
488 }
489 /* Special case: Huffman DC refinement scans need no Huffman table
490 * and therefore we can skip the optimization pass for them.
491 */
492 master->pass_type = output_pass;
493 master->pass_number++;
494 /*FALLTHROUGH*/
495 #endif
496 case output_pass:
497 /* Do a data-output pass. */
498 /* We need not repeat per-scan setup if prior optimization pass did it. */
499 if (! cinfo->optimize_coding) {
500 select_scan_parameters(cinfo);
501 per_scan_setup(cinfo);
502 }
503 (*cinfo->entropy->start_pass) (cinfo, FALSE);
504 (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
505 /* We emit frame/scan headers now */
506 if (master->scan_number == 0)
507 (*cinfo->marker->write_frame_header) (cinfo);
508 (*cinfo->marker->write_scan_header) (cinfo);
509 master->pub.call_pass_startup = FALSE;
510 break;
511 default:
512 ERREXIT(cinfo, JERR_NOT_COMPILED);
513 }
514
515 master->pub.is_last_pass = (master->pass_number == master->total_passes-1);
516
517 /* Set up progress monitor's pass info if present */
518 if (cinfo->progress != NULL) {
519 cinfo->progress->completed_passes = master->pass_number;
520 cinfo->progress->total_passes = master->total_passes;
521 }
522 }
523
524
525 /*
526 * Special start-of-pass hook.
527 * This is called by jpeg_write_scanlines if call_pass_startup is TRUE.
528 * In single-pass processing, we need this hook because we don't want to
529 * write frame/scan headers during jpeg_start_compress; we want to let the
530 * application write COM markers etc. between jpeg_start_compress and the
531 * jpeg_write_scanlines loop.
532 * In multi-pass processing, this routine is not used.
533 */
534
535 METHODDEF(void)
pass_startup(j_compress_ptr cinfo)536 pass_startup (j_compress_ptr cinfo)
537 {
538 cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */
539
540 (*cinfo->marker->write_frame_header) (cinfo);
541 (*cinfo->marker->write_scan_header) (cinfo);
542 }
543
544
545 /*
546 * Finish up at end of pass.
547 */
548
549 METHODDEF(void)
finish_pass_master(j_compress_ptr cinfo)550 finish_pass_master (j_compress_ptr cinfo)
551 {
552 my_master_ptr master = (my_master_ptr) cinfo->master;
553
554 /* The entropy coder always needs an end-of-pass call,
555 * either to analyze statistics or to flush its output buffer.
556 */
557 (*cinfo->entropy->finish_pass) (cinfo);
558
559 /* Update state for next pass */
560 switch (master->pass_type) {
561 case main_pass:
562 /* next pass is either output of scan 0 (after optimization)
563 * or output of scan 1 (if no optimization).
564 */
565 master->pass_type = output_pass;
566 if (! cinfo->optimize_coding)
567 master->scan_number++;
568 break;
569 case huff_opt_pass:
570 /* next pass is always output of current scan */
571 master->pass_type = output_pass;
572 break;
573 case output_pass:
574 /* next pass is either optimization or output of next scan */
575 if (cinfo->optimize_coding)
576 master->pass_type = huff_opt_pass;
577 master->scan_number++;
578 break;
579 }
580
581 master->pass_number++;
582 }
583
584
585 /*
586 * Initialize master compression control.
587 */
588
589 GLOBAL(void)
jinit_c_master_control(j_compress_ptr cinfo,boolean transcode_only)590 jinit_c_master_control (j_compress_ptr cinfo, boolean transcode_only)
591 {
592 my_master_ptr master;
593
594 master = (my_master_ptr)
595 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
596 sizeof(my_comp_master));
597 cinfo->master = (struct jpeg_comp_master *) master;
598 master->pub.prepare_for_pass = prepare_for_pass;
599 master->pub.pass_startup = pass_startup;
600 master->pub.finish_pass = finish_pass_master;
601 master->pub.is_last_pass = FALSE;
602
603 /* Validate parameters, determine derived values */
604 initial_setup(cinfo, transcode_only);
605
606 if (cinfo->scan_info != NULL) {
607 #ifdef C_MULTISCAN_FILES_SUPPORTED
608 validate_script(cinfo);
609 #else
610 ERREXIT(cinfo, JERR_NOT_COMPILED);
611 #endif
612 } else {
613 cinfo->progressive_mode = FALSE;
614 cinfo->num_scans = 1;
615 }
616
617 if (cinfo->progressive_mode && !cinfo->arith_code) /* TEMPORARY HACK ??? */
618 cinfo->optimize_coding = TRUE; /* assume default tables no good for progressive mode */
619
620 /* Initialize my private state */
621 if (transcode_only) {
622 /* no main pass in transcoding */
623 if (cinfo->optimize_coding)
624 master->pass_type = huff_opt_pass;
625 else
626 master->pass_type = output_pass;
627 } else {
628 /* for normal compression, first pass is always this type: */
629 master->pass_type = main_pass;
630 }
631 master->scan_number = 0;
632 master->pass_number = 0;
633 if (cinfo->optimize_coding)
634 master->total_passes = cinfo->num_scans * 2;
635 else
636 master->total_passes = cinfo->num_scans;
637
638 master->jpeg_version = PACKAGE_NAME " version " VERSION " (build " BUILD ")";
639 }
640