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.
8
* This file contains master control logic for the JPEG compressor.
9
* These routines are concerned with parameter validation, initial setup,
10
* and inter-pass control (determining the number of passes and the work
11
* to be done in each pass).
14
#define JPEG_INTERNALS
22
main_pass, /* input data, also do first output step */
23
huff_opt_pass, /* Huffman code optimization pass */
24
output_pass /* data output pass */
28
struct jpeg_comp_master pub; /* public fields */
30
c_pass_type pass_type; /* the type of the current pass */
32
int pass_number; /* # of passes completed */
33
int total_passes; /* total # of passes needed */
35
int scan_number; /* current index in scan_info[] */
38
typedef my_comp_master * my_master_ptr;
42
* Support routines that do various essential calculations.
46
initial_setup (j_compress_ptr cinfo)
47
/* Do computations that are needed before master selection phase */
50
jpeg_component_info *compptr;
52
JDIMENSION jd_samplesperrow;
54
/* Sanity check on image dimensions */
55
if (cinfo->image_height <= 0 || cinfo->image_width <= 0
56
|| cinfo->num_components <= 0 || cinfo->input_components <= 0)
57
ERREXIT(cinfo, JERR_EMPTY_IMAGE);
59
/* Make sure image isn't bigger than I can handle */
60
if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION ||
61
(long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)
62
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
64
/* Width of an input scanline must be representable as JDIMENSION. */
65
samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
66
jd_samplesperrow = (JDIMENSION) samplesperrow;
67
if ((long) jd_samplesperrow != samplesperrow)
68
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
70
/* For now, precision must match compiled-in value... */
71
if (cinfo->data_precision != BITS_IN_JSAMPLE)
72
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
74
/* Check that number of components won't exceed internal array sizes */
75
if (cinfo->num_components > MAX_COMPONENTS)
76
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
79
/* Compute maximum sampling factors; check factor validity */
80
cinfo->max_h_samp_factor = 1;
81
cinfo->max_v_samp_factor = 1;
82
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
84
if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
85
compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
86
ERREXIT(cinfo, JERR_BAD_SAMPLING);
87
cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
88
compptr->h_samp_factor);
89
cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
90
compptr->v_samp_factor);
93
/* Compute dimensions of components */
94
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
96
/* Fill in the correct component_index value; don't rely on application */
97
compptr->component_index = ci;
98
/* For compression, we never do DCT scaling. */
99
compptr->DCT_scaled_size = DCTSIZE;
100
/* Size in DCT blocks */
101
compptr->width_in_blocks = (JDIMENSION)
102
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
103
(long) (cinfo->max_h_samp_factor * DCTSIZE));
104
compptr->height_in_blocks = (JDIMENSION)
105
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
106
(long) (cinfo->max_v_samp_factor * DCTSIZE));
107
/* Size in samples */
108
compptr->downsampled_width = (JDIMENSION)
109
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
110
(long) cinfo->max_h_samp_factor);
111
compptr->downsampled_height = (JDIMENSION)
112
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
113
(long) cinfo->max_v_samp_factor);
114
/* Mark component needed (this flag isn't actually used for compression) */
115
compptr->component_needed = TRUE;
118
/* Compute number of fully interleaved MCU rows (number of times that
119
* main controller will call coefficient controller).
121
cinfo->total_iMCU_rows = (JDIMENSION)
122
jdiv_round_up((long) cinfo->image_height,
123
(long) (cinfo->max_v_samp_factor*DCTSIZE));
127
#ifdef C_MULTISCAN_FILES_SUPPORTED
130
validate_script (j_compress_ptr cinfo)
131
/* Verify that the scan script in cinfo->scan_info[] is valid; also
132
* determine whether it uses progressive JPEG, and set cinfo->progressive_mode.
135
const jpeg_scan_info * scanptr;
136
int scanno, ncomps, ci, coefi, thisi;
138
boolean component_sent[MAX_COMPONENTS];
139
#ifdef C_PROGRESSIVE_SUPPORTED
140
int * last_bitpos_ptr;
141
int last_bitpos[MAX_COMPONENTS][DCTSIZE2];
142
/* -1 until that coefficient has been seen; then last Al for it */
145
if (cinfo->num_scans <= 0)
146
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);
148
/* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
149
* for progressive JPEG, no scan can have this.
151
scanptr = cinfo->scan_info;
152
if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) {
153
#ifdef C_PROGRESSIVE_SUPPORTED
154
cinfo->progressive_mode = TRUE;
155
last_bitpos_ptr = & last_bitpos[0][0];
156
for (ci = 0; ci < cinfo->num_components; ci++)
157
for (coefi = 0; coefi < DCTSIZE2; coefi++)
158
*last_bitpos_ptr++ = -1;
160
ERREXIT(cinfo, JERR_NOT_COMPILED);
163
cinfo->progressive_mode = FALSE;
164
for (ci = 0; ci < cinfo->num_components; ci++)
165
component_sent[ci] = FALSE;
168
for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {
169
/* Validate component indexes */
170
ncomps = scanptr->comps_in_scan;
171
if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)
172
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
173
for (ci = 0; ci < ncomps; ci++) {
174
thisi = scanptr->component_index[ci];
175
if (thisi < 0 || thisi >= cinfo->num_components)
176
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
177
/* Components must appear in SOF order within each scan */
178
if (ci > 0 && thisi <= scanptr->component_index[ci-1])
179
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
181
/* Validate progression parameters */
186
if (cinfo->progressive_mode) {
187
#ifdef C_PROGRESSIVE_SUPPORTED
188
/* The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that
189
* seems wrong: the upper bound ought to depend on data precision.
190
* Perhaps they really meant 0..N+1 for N-bit precision.
191
* Here we allow 0..10 for 8-bit data; Al larger than 10 results in
192
* out-of-range reconstructed DC values during the first DC scan,
193
* which might cause problems for some decoders.
195
#if BITS_IN_JSAMPLE == 8
200
if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||
201
Ah < 0 || Ah > MAX_AH_AL || Al < 0 || Al > MAX_AH_AL)
202
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
204
if (Se != 0) /* DC and AC together not OK */
205
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
207
if (ncomps != 1) /* AC scans must be for only one component */
208
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
210
for (ci = 0; ci < ncomps; ci++) {
211
last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0];
212
if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */
213
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
214
for (coefi = Ss; coefi <= Se; coefi++) {
215
if (last_bitpos_ptr[coefi] < 0) {
216
/* first scan of this coefficient */
218
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
221
if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1)
222
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
224
last_bitpos_ptr[coefi] = Al;
229
/* For sequential JPEG, all progression parameters must be these: */
230
if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0)
231
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
232
/* Make sure components are not sent twice */
233
for (ci = 0; ci < ncomps; ci++) {
234
thisi = scanptr->component_index[ci];
235
if (component_sent[thisi])
236
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
237
component_sent[thisi] = TRUE;
242
/* Now verify that everything got sent. */
243
if (cinfo->progressive_mode) {
244
#ifdef C_PROGRESSIVE_SUPPORTED
245
/* For progressive mode, we only check that at least some DC data
246
* got sent for each component; the spec does not require that all bits
247
* of all coefficients be transmitted. Would it be wiser to enforce
248
* transmission of all coefficient bits??
250
for (ci = 0; ci < cinfo->num_components; ci++) {
251
if (last_bitpos[ci][0] < 0)
252
ERREXIT(cinfo, JERR_MISSING_DATA);
256
for (ci = 0; ci < cinfo->num_components; ci++) {
257
if (! component_sent[ci])
258
ERREXIT(cinfo, JERR_MISSING_DATA);
263
#endif /* C_MULTISCAN_FILES_SUPPORTED */
267
select_scan_parameters (j_compress_ptr cinfo)
268
/* Set up the scan parameters for the current scan */
272
#ifdef C_MULTISCAN_FILES_SUPPORTED
273
if (cinfo->scan_info != NULL) {
274
/* Prepare for current scan --- the script is already validated */
275
my_master_ptr master = (my_master_ptr) cinfo->master;
276
const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number;
278
cinfo->comps_in_scan = scanptr->comps_in_scan;
279
for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
280
cinfo->cur_comp_info[ci] =
281
&cinfo->comp_info[scanptr->component_index[ci]];
283
cinfo->Ss = scanptr->Ss;
284
cinfo->Se = scanptr->Se;
285
cinfo->Ah = scanptr->Ah;
286
cinfo->Al = scanptr->Al;
291
/* Prepare for single sequential-JPEG scan containing all components */
292
if (cinfo->num_components > MAX_COMPS_IN_SCAN)
293
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
295
cinfo->comps_in_scan = cinfo->num_components;
296
for (ci = 0; ci < cinfo->num_components; ci++) {
297
cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
300
cinfo->Se = DCTSIZE2-1;
308
per_scan_setup (j_compress_ptr cinfo)
309
/* Do computations that are needed before processing a JPEG scan */
310
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
312
int ci, mcublks, tmp;
313
jpeg_component_info *compptr;
315
if (cinfo->comps_in_scan == 1) {
317
/* Noninterleaved (single-component) scan */
318
compptr = cinfo->cur_comp_info[0];
320
/* Overall image size in MCUs */
321
cinfo->MCUs_per_row = compptr->width_in_blocks;
322
cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
324
/* For noninterleaved scan, always one block per MCU */
325
compptr->MCU_width = 1;
326
compptr->MCU_height = 1;
327
compptr->MCU_blocks = 1;
328
compptr->MCU_sample_width = DCTSIZE;
329
compptr->last_col_width = 1;
330
/* For noninterleaved scans, it is convenient to define last_row_height
331
* as the number of block rows present in the last iMCU row.
333
tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
334
if (tmp == 0) tmp = compptr->v_samp_factor;
335
compptr->last_row_height = tmp;
337
/* Prepare array describing MCU composition */
338
cinfo->blocks_in_MCU = 1;
339
cinfo->MCU_membership[0] = 0;
343
/* Interleaved (multi-component) scan */
344
if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
345
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
348
/* Overall image size in MCUs */
349
cinfo->MCUs_per_row = (JDIMENSION)
350
jdiv_round_up((long) cinfo->image_width,
351
(long) (cinfo->max_h_samp_factor*DCTSIZE));
352
cinfo->MCU_rows_in_scan = (JDIMENSION)
353
jdiv_round_up((long) cinfo->image_height,
354
(long) (cinfo->max_v_samp_factor*DCTSIZE));
356
cinfo->blocks_in_MCU = 0;
358
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
359
compptr = cinfo->cur_comp_info[ci];
360
/* Sampling factors give # of blocks of component in each MCU */
361
compptr->MCU_width = compptr->h_samp_factor;
362
compptr->MCU_height = compptr->v_samp_factor;
363
compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
364
compptr->MCU_sample_width = compptr->MCU_width * DCTSIZE;
365
/* Figure number of non-dummy blocks in last MCU column & row */
366
tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
367
if (tmp == 0) tmp = compptr->MCU_width;
368
compptr->last_col_width = tmp;
369
tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
370
if (tmp == 0) tmp = compptr->MCU_height;
371
compptr->last_row_height = tmp;
372
/* Prepare array describing MCU composition */
373
mcublks = compptr->MCU_blocks;
374
if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)
375
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
376
while (mcublks-- > 0) {
377
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
383
/* Convert restart specified in rows to actual MCU count. */
384
/* Note that count must fit in 16 bits, so we provide limiting. */
385
if (cinfo->restart_in_rows > 0) {
386
long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;
387
cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);
394
* This is called at the beginning of each pass. We determine which modules
395
* will be active during this pass and give them appropriate start_pass calls.
396
* We also set is_last_pass to indicate whether any more passes will be
401
prepare_for_pass (j_compress_ptr cinfo)
403
my_master_ptr master = (my_master_ptr) cinfo->master;
405
switch (master->pass_type) {
407
/* Initial pass: will collect input data, and do either Huffman
408
* optimization or data output for the first scan.
410
select_scan_parameters(cinfo);
411
per_scan_setup(cinfo);
412
if (! cinfo->raw_data_in) {
413
(*cinfo->cconvert->start_pass) (cinfo);
414
(*cinfo->downsample->start_pass) (cinfo);
415
(*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);
417
(*cinfo->fdct->start_pass) (cinfo);
418
(*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);
419
(*cinfo->coef->start_pass) (cinfo,
420
(master->total_passes > 1 ?
421
JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
422
(*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
423
if (cinfo->optimize_coding) {
424
/* No immediate data output; postpone writing frame/scan headers */
425
master->pub.call_pass_startup = FALSE;
427
/* Will write frame/scan headers at first jpeg_write_scanlines call */
428
master->pub.call_pass_startup = TRUE;
431
#ifdef ENTROPY_OPT_SUPPORTED
433
/* Do Huffman optimization for a scan after the first one. */
434
select_scan_parameters(cinfo);
435
per_scan_setup(cinfo);
436
if (cinfo->Ss != 0 || cinfo->Ah == 0 || cinfo->arith_code) {
437
(*cinfo->entropy->start_pass) (cinfo, TRUE);
438
(*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
439
master->pub.call_pass_startup = FALSE;
442
/* Special case: Huffman DC refinement scans need no Huffman table
443
* and therefore we can skip the optimization pass for them.
445
master->pass_type = output_pass;
446
master->pass_number++;
450
/* Do a data-output pass. */
451
/* We need not repeat per-scan setup if prior optimization pass did it. */
452
if (! cinfo->optimize_coding) {
453
select_scan_parameters(cinfo);
454
per_scan_setup(cinfo);
456
(*cinfo->entropy->start_pass) (cinfo, FALSE);
457
(*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
458
/* We emit frame/scan headers now */
459
if (master->scan_number == 0)
460
(*cinfo->marker->write_frame_header) (cinfo);
461
(*cinfo->marker->write_scan_header) (cinfo);
462
master->pub.call_pass_startup = FALSE;
465
ERREXIT(cinfo, JERR_NOT_COMPILED);
468
master->pub.is_last_pass = (master->pass_number == master->total_passes-1);
470
/* Set up progress monitor's pass info if present */
471
if (cinfo->progress != NULL) {
472
cinfo->progress->completed_passes = master->pass_number;
473
cinfo->progress->total_passes = master->total_passes;
479
* Special start-of-pass hook.
480
* This is called by jpeg_write_scanlines if call_pass_startup is TRUE.
481
* In single-pass processing, we need this hook because we don't want to
482
* write frame/scan headers during jpeg_start_compress; we want to let the
483
* application write COM markers etc. between jpeg_start_compress and the
484
* jpeg_write_scanlines loop.
485
* In multi-pass processing, this routine is not used.
489
pass_startup (j_compress_ptr cinfo)
491
cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */
493
(*cinfo->marker->write_frame_header) (cinfo);
494
(*cinfo->marker->write_scan_header) (cinfo);
499
* Finish up at end of pass.
503
finish_pass_master (j_compress_ptr cinfo)
505
my_master_ptr master = (my_master_ptr) cinfo->master;
507
/* The entropy coder always needs an end-of-pass call,
508
* either to analyze statistics or to flush its output buffer.
510
(*cinfo->entropy->finish_pass) (cinfo);
512
/* Update state for next pass */
513
switch (master->pass_type) {
515
/* next pass is either output of scan 0 (after optimization)
516
* or output of scan 1 (if no optimization).
518
master->pass_type = output_pass;
519
if (! cinfo->optimize_coding)
520
master->scan_number++;
523
/* next pass is always output of current scan */
524
master->pass_type = output_pass;
527
/* next pass is either optimization or output of next scan */
528
if (cinfo->optimize_coding)
529
master->pass_type = huff_opt_pass;
530
master->scan_number++;
534
master->pass_number++;
539
* Initialize master compression control.
543
jinit_c_master_control (j_compress_ptr cinfo, boolean transcode_only)
545
my_master_ptr master;
547
master = (my_master_ptr)
548
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
549
SIZEOF(my_comp_master));
550
cinfo->master = (struct jpeg_comp_master *) master;
551
master->pub.prepare_for_pass = prepare_for_pass;
552
master->pub.pass_startup = pass_startup;
553
master->pub.finish_pass = finish_pass_master;
554
master->pub.is_last_pass = FALSE;
556
/* Validate parameters, determine derived values */
557
initial_setup(cinfo);
559
if (cinfo->scan_info != NULL) {
560
#ifdef C_MULTISCAN_FILES_SUPPORTED
561
validate_script(cinfo);
563
ERREXIT(cinfo, JERR_NOT_COMPILED);
566
cinfo->progressive_mode = FALSE;
567
cinfo->num_scans = 1;
570
if (cinfo->progressive_mode) /* TEMPORARY HACK ??? */
571
cinfo->optimize_coding = TRUE; /* assume default tables no good for progressive mode */
573
/* Initialize my private state */
574
if (transcode_only) {
575
/* no main pass in transcoding */
576
if (cinfo->optimize_coding)
577
master->pass_type = huff_opt_pass;
579
master->pass_type = output_pass;
581
/* for normal compression, first pass is always this type: */
582
master->pass_type = main_pass;
584
master->scan_number = 0;
585
master->pass_number = 0;
586
if (cinfo->optimize_coding)
587
master->total_passes = cinfo->num_scans * 2;
589
master->total_passes = cinfo->num_scans;
added
removed
binsrc/samples/TPC-W/IMAGEGEN/ImgFiles/jcmaster.c
