4
* Copyright (C) 1991-1997, Thomas G. Lane.
5
* Modified 2003-2011 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.
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).
15
#define JPEG_INTERNALS
23
main_pass, /* input data, also do first output step */
24
huff_opt_pass, /* Huffman code optimization pass */
25
output_pass /* data output pass */
29
struct jpeg_comp_master pub; /* public fields */
31
c_pass_type pass_type; /* the type of the current pass */
33
int pass_number; /* # of passes completed */
34
int total_passes; /* total # of passes needed */
36
int scan_number; /* current index in scan_info[] */
39
typedef my_comp_master * my_master_ptr;
43
* Support routines that do various essential calculations.
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.
53
jpeg_calc_jpeg_dimensions (j_compress_ptr cinfo)
54
/* Do computations that are needed before master selection phase */
56
#ifdef DCT_SCALING_SUPPORTED
58
/* Sanity check on input image dimensions to prevent overflow in
59
* following calculation.
60
* We do check jpeg_width and jpeg_height in initial_setup below,
61
* but image_width and image_height can come from arbitrary data,
62
* and we need some space for multiplication by block_size.
64
if (((long) cinfo->image_width >> 24) || ((long) cinfo->image_height >> 24))
65
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
67
/* Compute actual JPEG image dimensions and DCT scaling choices. */
68
if (cinfo->scale_num >= cinfo->scale_denom * cinfo->block_size) {
69
/* Provide block_size/1 scaling */
70
cinfo->jpeg_width = cinfo->image_width * cinfo->block_size;
71
cinfo->jpeg_height = cinfo->image_height * cinfo->block_size;
72
cinfo->min_DCT_h_scaled_size = 1;
73
cinfo->min_DCT_v_scaled_size = 1;
74
} else if (cinfo->scale_num * 2 >= cinfo->scale_denom * cinfo->block_size) {
75
/* Provide block_size/2 scaling */
76
cinfo->jpeg_width = (JDIMENSION)
77
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 2L);
78
cinfo->jpeg_height = (JDIMENSION)
79
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 2L);
80
cinfo->min_DCT_h_scaled_size = 2;
81
cinfo->min_DCT_v_scaled_size = 2;
82
} else if (cinfo->scale_num * 3 >= cinfo->scale_denom * cinfo->block_size) {
83
/* Provide block_size/3 scaling */
84
cinfo->jpeg_width = (JDIMENSION)
85
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 3L);
86
cinfo->jpeg_height = (JDIMENSION)
87
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 3L);
88
cinfo->min_DCT_h_scaled_size = 3;
89
cinfo->min_DCT_v_scaled_size = 3;
90
} else if (cinfo->scale_num * 4 >= cinfo->scale_denom * cinfo->block_size) {
91
/* Provide block_size/4 scaling */
92
cinfo->jpeg_width = (JDIMENSION)
93
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 4L);
94
cinfo->jpeg_height = (JDIMENSION)
95
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 4L);
96
cinfo->min_DCT_h_scaled_size = 4;
97
cinfo->min_DCT_v_scaled_size = 4;
98
} else if (cinfo->scale_num * 5 >= cinfo->scale_denom * cinfo->block_size) {
99
/* Provide block_size/5 scaling */
100
cinfo->jpeg_width = (JDIMENSION)
101
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 5L);
102
cinfo->jpeg_height = (JDIMENSION)
103
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 5L);
104
cinfo->min_DCT_h_scaled_size = 5;
105
cinfo->min_DCT_v_scaled_size = 5;
106
} else if (cinfo->scale_num * 6 >= cinfo->scale_denom * cinfo->block_size) {
107
/* Provide block_size/6 scaling */
108
cinfo->jpeg_width = (JDIMENSION)
109
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 6L);
110
cinfo->jpeg_height = (JDIMENSION)
111
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 6L);
112
cinfo->min_DCT_h_scaled_size = 6;
113
cinfo->min_DCT_v_scaled_size = 6;
114
} else if (cinfo->scale_num * 7 >= cinfo->scale_denom * cinfo->block_size) {
115
/* Provide block_size/7 scaling */
116
cinfo->jpeg_width = (JDIMENSION)
117
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 7L);
118
cinfo->jpeg_height = (JDIMENSION)
119
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 7L);
120
cinfo->min_DCT_h_scaled_size = 7;
121
cinfo->min_DCT_v_scaled_size = 7;
122
} else if (cinfo->scale_num * 8 >= cinfo->scale_denom * cinfo->block_size) {
123
/* Provide block_size/8 scaling */
124
cinfo->jpeg_width = (JDIMENSION)
125
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 8L);
126
cinfo->jpeg_height = (JDIMENSION)
127
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 8L);
128
cinfo->min_DCT_h_scaled_size = 8;
129
cinfo->min_DCT_v_scaled_size = 8;
130
} else if (cinfo->scale_num * 9 >= cinfo->scale_denom * cinfo->block_size) {
131
/* Provide block_size/9 scaling */
132
cinfo->jpeg_width = (JDIMENSION)
133
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 9L);
134
cinfo->jpeg_height = (JDIMENSION)
135
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 9L);
136
cinfo->min_DCT_h_scaled_size = 9;
137
cinfo->min_DCT_v_scaled_size = 9;
138
} else if (cinfo->scale_num * 10 >= cinfo->scale_denom * cinfo->block_size) {
139
/* Provide block_size/10 scaling */
140
cinfo->jpeg_width = (JDIMENSION)
141
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 10L);
142
cinfo->jpeg_height = (JDIMENSION)
143
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 10L);
144
cinfo->min_DCT_h_scaled_size = 10;
145
cinfo->min_DCT_v_scaled_size = 10;
146
} else if (cinfo->scale_num * 11 >= cinfo->scale_denom * cinfo->block_size) {
147
/* Provide block_size/11 scaling */
148
cinfo->jpeg_width = (JDIMENSION)
149
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 11L);
150
cinfo->jpeg_height = (JDIMENSION)
151
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 11L);
152
cinfo->min_DCT_h_scaled_size = 11;
153
cinfo->min_DCT_v_scaled_size = 11;
154
} else if (cinfo->scale_num * 12 >= cinfo->scale_denom * cinfo->block_size) {
155
/* Provide block_size/12 scaling */
156
cinfo->jpeg_width = (JDIMENSION)
157
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 12L);
158
cinfo->jpeg_height = (JDIMENSION)
159
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 12L);
160
cinfo->min_DCT_h_scaled_size = 12;
161
cinfo->min_DCT_v_scaled_size = 12;
162
} else if (cinfo->scale_num * 13 >= cinfo->scale_denom * cinfo->block_size) {
163
/* Provide block_size/13 scaling */
164
cinfo->jpeg_width = (JDIMENSION)
165
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 13L);
166
cinfo->jpeg_height = (JDIMENSION)
167
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 13L);
168
cinfo->min_DCT_h_scaled_size = 13;
169
cinfo->min_DCT_v_scaled_size = 13;
170
} else if (cinfo->scale_num * 14 >= cinfo->scale_denom * cinfo->block_size) {
171
/* Provide block_size/14 scaling */
172
cinfo->jpeg_width = (JDIMENSION)
173
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 14L);
174
cinfo->jpeg_height = (JDIMENSION)
175
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 14L);
176
cinfo->min_DCT_h_scaled_size = 14;
177
cinfo->min_DCT_v_scaled_size = 14;
178
} else if (cinfo->scale_num * 15 >= cinfo->scale_denom * cinfo->block_size) {
179
/* Provide block_size/15 scaling */
180
cinfo->jpeg_width = (JDIMENSION)
181
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 15L);
182
cinfo->jpeg_height = (JDIMENSION)
183
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 15L);
184
cinfo->min_DCT_h_scaled_size = 15;
185
cinfo->min_DCT_v_scaled_size = 15;
187
/* Provide block_size/16 scaling */
188
cinfo->jpeg_width = (JDIMENSION)
189
jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 16L);
190
cinfo->jpeg_height = (JDIMENSION)
191
jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 16L);
192
cinfo->min_DCT_h_scaled_size = 16;
193
cinfo->min_DCT_v_scaled_size = 16;
196
#else /* !DCT_SCALING_SUPPORTED */
198
/* Hardwire it to "no scaling" */
199
cinfo->jpeg_width = cinfo->image_width;
200
cinfo->jpeg_height = cinfo->image_height;
201
cinfo->min_DCT_h_scaled_size = DCTSIZE;
202
cinfo->min_DCT_v_scaled_size = DCTSIZE;
204
#endif /* DCT_SCALING_SUPPORTED */
209
jpeg_calc_trans_dimensions (j_compress_ptr cinfo)
211
if (cinfo->min_DCT_h_scaled_size != cinfo->min_DCT_v_scaled_size)
212
ERREXIT2(cinfo, JERR_BAD_DCTSIZE,
213
cinfo->min_DCT_h_scaled_size, cinfo->min_DCT_v_scaled_size);
215
cinfo->block_size = cinfo->min_DCT_h_scaled_size;
220
initial_setup (j_compress_ptr cinfo, boolean transcode_only)
221
/* Do computations that are needed before master selection phase */
224
jpeg_component_info *compptr;
226
JDIMENSION jd_samplesperrow;
229
jpeg_calc_trans_dimensions(cinfo);
231
jpeg_calc_jpeg_dimensions(cinfo);
233
/* Sanity check on block_size */
234
if (cinfo->block_size < 1 || cinfo->block_size > 16)
235
ERREXIT2(cinfo, JERR_BAD_DCTSIZE, cinfo->block_size, cinfo->block_size);
237
/* Derive natural_order from block_size */
238
switch (cinfo->block_size) {
239
case 2: cinfo->natural_order = jpeg_natural_order2; break;
240
case 3: cinfo->natural_order = jpeg_natural_order3; break;
241
case 4: cinfo->natural_order = jpeg_natural_order4; break;
242
case 5: cinfo->natural_order = jpeg_natural_order5; break;
243
case 6: cinfo->natural_order = jpeg_natural_order6; break;
244
case 7: cinfo->natural_order = jpeg_natural_order7; break;
245
default: cinfo->natural_order = jpeg_natural_order; break;
248
/* Derive lim_Se from block_size */
249
cinfo->lim_Se = cinfo->block_size < DCTSIZE ?
250
cinfo->block_size * cinfo->block_size - 1 : DCTSIZE2-1;
252
/* Sanity check on image dimensions */
253
if (cinfo->jpeg_height <= 0 || cinfo->jpeg_width <= 0 ||
254
cinfo->num_components <= 0 || cinfo->input_components <= 0)
255
ERREXIT(cinfo, JERR_EMPTY_IMAGE);
257
/* Make sure image isn't bigger than I can handle */
258
if ((long) cinfo->jpeg_height > (long) JPEG_MAX_DIMENSION ||
259
(long) cinfo->jpeg_width > (long) JPEG_MAX_DIMENSION)
260
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
262
/* Width of an input scanline must be representable as JDIMENSION. */
263
samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
264
jd_samplesperrow = (JDIMENSION) samplesperrow;
265
if ((long) jd_samplesperrow != samplesperrow)
266
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
268
/* For now, precision must match compiled-in value... */
269
if (cinfo->data_precision != BITS_IN_JSAMPLE)
270
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
272
/* Check that number of components won't exceed internal array sizes */
273
if (cinfo->num_components > MAX_COMPONENTS)
274
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
277
/* Compute maximum sampling factors; check factor validity */
278
cinfo->max_h_samp_factor = 1;
279
cinfo->max_v_samp_factor = 1;
280
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
282
if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
283
compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
284
ERREXIT(cinfo, JERR_BAD_SAMPLING);
285
cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
286
compptr->h_samp_factor);
287
cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
288
compptr->v_samp_factor);
291
/* Compute dimensions of components */
292
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
294
/* Fill in the correct component_index value; don't rely on application */
295
compptr->component_index = ci;
296
/* In selecting the actual DCT scaling for each component, we try to
297
* scale down the chroma components via DCT scaling rather than downsampling.
298
* This saves time if the downsampler gets to use 1:1 scaling.
299
* Note this code adapts subsampling ratios which are powers of 2.
302
#ifdef DCT_SCALING_SUPPORTED
303
while (cinfo->min_DCT_h_scaled_size * ssize <=
304
(cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
305
(cinfo->max_h_samp_factor % (compptr->h_samp_factor * ssize * 2)) == 0) {
309
compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size * ssize;
311
#ifdef DCT_SCALING_SUPPORTED
312
while (cinfo->min_DCT_v_scaled_size * ssize <=
313
(cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
314
(cinfo->max_v_samp_factor % (compptr->v_samp_factor * ssize * 2)) == 0) {
318
compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size * ssize;
320
/* We don't support DCT ratios larger than 2. */
321
if (compptr->DCT_h_scaled_size > compptr->DCT_v_scaled_size * 2)
322
compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size * 2;
323
else if (compptr->DCT_v_scaled_size > compptr->DCT_h_scaled_size * 2)
324
compptr->DCT_v_scaled_size = compptr->DCT_h_scaled_size * 2;
326
/* Size in DCT blocks */
327
compptr->width_in_blocks = (JDIMENSION)
328
jdiv_round_up((long) cinfo->jpeg_width * (long) compptr->h_samp_factor,
329
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
330
compptr->height_in_blocks = (JDIMENSION)
331
jdiv_round_up((long) cinfo->jpeg_height * (long) compptr->v_samp_factor,
332
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
333
/* Size in samples */
334
compptr->downsampled_width = (JDIMENSION)
335
jdiv_round_up((long) cinfo->jpeg_width *
336
(long) (compptr->h_samp_factor * compptr->DCT_h_scaled_size),
337
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
338
compptr->downsampled_height = (JDIMENSION)
339
jdiv_round_up((long) cinfo->jpeg_height *
340
(long) (compptr->v_samp_factor * compptr->DCT_v_scaled_size),
341
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
342
/* Mark component needed (this flag isn't actually used for compression) */
343
compptr->component_needed = TRUE;
346
/* Compute number of fully interleaved MCU rows (number of times that
347
* main controller will call coefficient controller).
349
cinfo->total_iMCU_rows = (JDIMENSION)
350
jdiv_round_up((long) cinfo->jpeg_height,
351
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
355
#ifdef C_MULTISCAN_FILES_SUPPORTED
358
validate_script (j_compress_ptr cinfo)
359
/* Verify that the scan script in cinfo->scan_info[] is valid; also
360
* determine whether it uses progressive JPEG, and set cinfo->progressive_mode.
363
const jpeg_scan_info * scanptr;
364
int scanno, ncomps, ci, coefi, thisi;
366
boolean component_sent[MAX_COMPONENTS];
367
#ifdef C_PROGRESSIVE_SUPPORTED
368
int * last_bitpos_ptr;
369
int last_bitpos[MAX_COMPONENTS][DCTSIZE2];
370
/* -1 until that coefficient has been seen; then last Al for it */
373
if (cinfo->num_scans <= 0)
374
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);
376
/* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
377
* for progressive JPEG, no scan can have this.
379
scanptr = cinfo->scan_info;
380
if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) {
381
#ifdef C_PROGRESSIVE_SUPPORTED
382
cinfo->progressive_mode = TRUE;
383
last_bitpos_ptr = & last_bitpos[0][0];
384
for (ci = 0; ci < cinfo->num_components; ci++)
385
for (coefi = 0; coefi < DCTSIZE2; coefi++)
386
*last_bitpos_ptr++ = -1;
388
ERREXIT(cinfo, JERR_NOT_COMPILED);
391
cinfo->progressive_mode = FALSE;
392
for (ci = 0; ci < cinfo->num_components; ci++)
393
component_sent[ci] = FALSE;
396
for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {
397
/* Validate component indexes */
398
ncomps = scanptr->comps_in_scan;
399
if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)
400
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
401
for (ci = 0; ci < ncomps; ci++) {
402
thisi = scanptr->component_index[ci];
403
if (thisi < 0 || thisi >= cinfo->num_components)
404
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
405
/* Components must appear in SOF order within each scan */
406
if (ci > 0 && thisi <= scanptr->component_index[ci-1])
407
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
409
/* Validate progression parameters */
414
if (cinfo->progressive_mode) {
415
#ifdef C_PROGRESSIVE_SUPPORTED
416
/* The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that
417
* seems wrong: the upper bound ought to depend on data precision.
418
* Perhaps they really meant 0..N+1 for N-bit precision.
419
* Here we allow 0..10 for 8-bit data; Al larger than 10 results in
420
* out-of-range reconstructed DC values during the first DC scan,
421
* which might cause problems for some decoders.
423
#if BITS_IN_JSAMPLE == 8
428
if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||
429
Ah < 0 || Ah > MAX_AH_AL || Al < 0 || Al > MAX_AH_AL)
430
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
432
if (Se != 0) /* DC and AC together not OK */
433
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
435
if (ncomps != 1) /* AC scans must be for only one component */
436
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
438
for (ci = 0; ci < ncomps; ci++) {
439
last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0];
440
if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */
441
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
442
for (coefi = Ss; coefi <= Se; coefi++) {
443
if (last_bitpos_ptr[coefi] < 0) {
444
/* first scan of this coefficient */
446
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
449
if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1)
450
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
452
last_bitpos_ptr[coefi] = Al;
457
/* For sequential JPEG, all progression parameters must be these: */
458
if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0)
459
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
460
/* Make sure components are not sent twice */
461
for (ci = 0; ci < ncomps; ci++) {
462
thisi = scanptr->component_index[ci];
463
if (component_sent[thisi])
464
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
465
component_sent[thisi] = TRUE;
470
/* Now verify that everything got sent. */
471
if (cinfo->progressive_mode) {
472
#ifdef C_PROGRESSIVE_SUPPORTED
473
/* For progressive mode, we only check that at least some DC data
474
* got sent for each component; the spec does not require that all bits
475
* of all coefficients be transmitted. Would it be wiser to enforce
476
* transmission of all coefficient bits??
478
for (ci = 0; ci < cinfo->num_components; ci++) {
479
if (last_bitpos[ci][0] < 0)
480
ERREXIT(cinfo, JERR_MISSING_DATA);
484
for (ci = 0; ci < cinfo->num_components; ci++) {
485
if (! component_sent[ci])
486
ERREXIT(cinfo, JERR_MISSING_DATA);
493
reduce_script (j_compress_ptr cinfo)
494
/* Adapt scan script for use with reduced block size;
495
* assume that script has been validated before.
498
jpeg_scan_info * scanptr;
501
/* Circumvent const declaration for this function */
502
scanptr = (jpeg_scan_info *) cinfo->scan_info;
505
for (idxin = 0; idxin < cinfo->num_scans; idxin++) {
506
/* After skipping, idxout becomes smaller than idxin */
508
/* Copy rest of data;
509
* note we stay in given chunk of allocated memory.
511
scanptr[idxout] = scanptr[idxin];
512
if (scanptr[idxout].Ss > cinfo->lim_Se)
513
/* Entire scan out of range - skip this entry */
515
if (scanptr[idxout].Se > cinfo->lim_Se)
516
/* Limit scan to end of block */
517
scanptr[idxout].Se = cinfo->lim_Se;
521
cinfo->num_scans = idxout;
524
#endif /* C_MULTISCAN_FILES_SUPPORTED */
528
select_scan_parameters (j_compress_ptr cinfo)
529
/* Set up the scan parameters for the current scan */
533
#ifdef C_MULTISCAN_FILES_SUPPORTED
534
if (cinfo->scan_info != NULL) {
535
/* Prepare for current scan --- the script is already validated */
536
my_master_ptr master = (my_master_ptr) cinfo->master;
537
const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number;
539
cinfo->comps_in_scan = scanptr->comps_in_scan;
540
for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
541
cinfo->cur_comp_info[ci] =
542
&cinfo->comp_info[scanptr->component_index[ci]];
544
if (cinfo->progressive_mode) {
545
cinfo->Ss = scanptr->Ss;
546
cinfo->Se = scanptr->Se;
547
cinfo->Ah = scanptr->Ah;
548
cinfo->Al = scanptr->Al;
555
/* Prepare for single sequential-JPEG scan containing all components */
556
if (cinfo->num_components > MAX_COMPS_IN_SCAN)
557
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
559
cinfo->comps_in_scan = cinfo->num_components;
560
for (ci = 0; ci < cinfo->num_components; ci++) {
561
cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
565
cinfo->Se = cinfo->block_size * cinfo->block_size - 1;
572
per_scan_setup (j_compress_ptr cinfo)
573
/* Do computations that are needed before processing a JPEG scan */
574
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
576
int ci, mcublks, tmp;
577
jpeg_component_info *compptr;
579
if (cinfo->comps_in_scan == 1) {
581
/* Noninterleaved (single-component) scan */
582
compptr = cinfo->cur_comp_info[0];
584
/* Overall image size in MCUs */
585
cinfo->MCUs_per_row = compptr->width_in_blocks;
586
cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
588
/* For noninterleaved scan, always one block per MCU */
589
compptr->MCU_width = 1;
590
compptr->MCU_height = 1;
591
compptr->MCU_blocks = 1;
592
compptr->MCU_sample_width = compptr->DCT_h_scaled_size;
593
compptr->last_col_width = 1;
594
/* For noninterleaved scans, it is convenient to define last_row_height
595
* as the number of block rows present in the last iMCU row.
597
tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
598
if (tmp == 0) tmp = compptr->v_samp_factor;
599
compptr->last_row_height = tmp;
601
/* Prepare array describing MCU composition */
602
cinfo->blocks_in_MCU = 1;
603
cinfo->MCU_membership[0] = 0;
607
/* Interleaved (multi-component) scan */
608
if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
609
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
612
/* Overall image size in MCUs */
613
cinfo->MCUs_per_row = (JDIMENSION)
614
jdiv_round_up((long) cinfo->jpeg_width,
615
(long) (cinfo->max_h_samp_factor * cinfo->block_size));
616
cinfo->MCU_rows_in_scan = (JDIMENSION)
617
jdiv_round_up((long) cinfo->jpeg_height,
618
(long) (cinfo->max_v_samp_factor * cinfo->block_size));
620
cinfo->blocks_in_MCU = 0;
622
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
623
compptr = cinfo->cur_comp_info[ci];
624
/* Sampling factors give # of blocks of component in each MCU */
625
compptr->MCU_width = compptr->h_samp_factor;
626
compptr->MCU_height = compptr->v_samp_factor;
627
compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
628
compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_h_scaled_size;
629
/* Figure number of non-dummy blocks in last MCU column & row */
630
tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
631
if (tmp == 0) tmp = compptr->MCU_width;
632
compptr->last_col_width = tmp;
633
tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
634
if (tmp == 0) tmp = compptr->MCU_height;
635
compptr->last_row_height = tmp;
636
/* Prepare array describing MCU composition */
637
mcublks = compptr->MCU_blocks;
638
if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)
639
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
640
while (mcublks-- > 0) {
641
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
647
/* Convert restart specified in rows to actual MCU count. */
648
/* Note that count must fit in 16 bits, so we provide limiting. */
649
if (cinfo->restart_in_rows > 0) {
650
long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;
651
cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);
658
* This is called at the beginning of each pass. We determine which modules
659
* will be active during this pass and give them appropriate start_pass calls.
660
* We also set is_last_pass to indicate whether any more passes will be
665
prepare_for_pass (j_compress_ptr cinfo)
667
my_master_ptr master = (my_master_ptr) cinfo->master;
669
switch (master->pass_type) {
671
/* Initial pass: will collect input data, and do either Huffman
672
* optimization or data output for the first scan.
674
select_scan_parameters(cinfo);
675
per_scan_setup(cinfo);
676
if (! cinfo->raw_data_in) {
677
(*cinfo->cconvert->start_pass) (cinfo);
678
(*cinfo->downsample->start_pass) (cinfo);
679
(*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);
681
(*cinfo->fdct->start_pass) (cinfo);
682
(*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);
683
(*cinfo->coef->start_pass) (cinfo,
684
(master->total_passes > 1 ?
685
JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
686
(*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
687
if (cinfo->optimize_coding) {
688
/* No immediate data output; postpone writing frame/scan headers */
689
master->pub.call_pass_startup = FALSE;
691
/* Will write frame/scan headers at first jpeg_write_scanlines call */
692
master->pub.call_pass_startup = TRUE;
695
#ifdef ENTROPY_OPT_SUPPORTED
697
/* Do Huffman optimization for a scan after the first one. */
698
select_scan_parameters(cinfo);
699
per_scan_setup(cinfo);
700
if (cinfo->Ss != 0 || cinfo->Ah == 0) {
701
(*cinfo->entropy->start_pass) (cinfo, TRUE);
702
(*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
703
master->pub.call_pass_startup = FALSE;
706
/* Special case: Huffman DC refinement scans need no Huffman table
707
* and therefore we can skip the optimization pass for them.
709
master->pass_type = output_pass;
710
master->pass_number++;
714
/* Do a data-output pass. */
715
/* We need not repeat per-scan setup if prior optimization pass did it. */
716
if (! cinfo->optimize_coding) {
717
select_scan_parameters(cinfo);
718
per_scan_setup(cinfo);
720
(*cinfo->entropy->start_pass) (cinfo, FALSE);
721
(*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
722
/* We emit frame/scan headers now */
723
if (master->scan_number == 0)
724
(*cinfo->marker->write_frame_header) (cinfo);
725
(*cinfo->marker->write_scan_header) (cinfo);
726
master->pub.call_pass_startup = FALSE;
729
ERREXIT(cinfo, JERR_NOT_COMPILED);
732
master->pub.is_last_pass = (master->pass_number == master->total_passes-1);
734
/* Set up progress monitor's pass info if present */
735
if (cinfo->progress != NULL) {
736
cinfo->progress->completed_passes = master->pass_number;
737
cinfo->progress->total_passes = master->total_passes;
743
* Special start-of-pass hook.
744
* This is called by jpeg_write_scanlines if call_pass_startup is TRUE.
745
* In single-pass processing, we need this hook because we don't want to
746
* write frame/scan headers during jpeg_start_compress; we want to let the
747
* application write COM markers etc. between jpeg_start_compress and the
748
* jpeg_write_scanlines loop.
749
* In multi-pass processing, this routine is not used.
753
pass_startup (j_compress_ptr cinfo)
755
cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */
757
(*cinfo->marker->write_frame_header) (cinfo);
758
(*cinfo->marker->write_scan_header) (cinfo);
763
* Finish up at end of pass.
767
finish_pass_master (j_compress_ptr cinfo)
769
my_master_ptr master = (my_master_ptr) cinfo->master;
771
/* The entropy coder always needs an end-of-pass call,
772
* either to analyze statistics or to flush its output buffer.
774
(*cinfo->entropy->finish_pass) (cinfo);
776
/* Update state for next pass */
777
switch (master->pass_type) {
779
/* next pass is either output of scan 0 (after optimization)
780
* or output of scan 1 (if no optimization).
782
master->pass_type = output_pass;
783
if (! cinfo->optimize_coding)
784
master->scan_number++;
787
/* next pass is always output of current scan */
788
master->pass_type = output_pass;
791
/* next pass is either optimization or output of next scan */
792
if (cinfo->optimize_coding)
793
master->pass_type = huff_opt_pass;
794
master->scan_number++;
798
master->pass_number++;
803
* Initialize master compression control.
807
jinit_c_master_control (j_compress_ptr cinfo, boolean transcode_only)
809
my_master_ptr master;
811
master = (my_master_ptr)
812
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
813
SIZEOF(my_comp_master));
814
cinfo->master = (struct jpeg_comp_master *) master;
815
master->pub.prepare_for_pass = prepare_for_pass;
816
master->pub.pass_startup = pass_startup;
817
master->pub.finish_pass = finish_pass_master;
818
master->pub.is_last_pass = FALSE;
820
/* Validate parameters, determine derived values */
821
initial_setup(cinfo, transcode_only);
823
if (cinfo->scan_info != NULL) {
824
#ifdef C_MULTISCAN_FILES_SUPPORTED
825
validate_script(cinfo);
826
if (cinfo->block_size < DCTSIZE)
827
reduce_script(cinfo);
829
ERREXIT(cinfo, JERR_NOT_COMPILED);
832
cinfo->progressive_mode = FALSE;
833
cinfo->num_scans = 1;
836
if ((cinfo->progressive_mode || cinfo->block_size < DCTSIZE) &&
837
!cinfo->arith_code) /* TEMPORARY HACK ??? */
838
/* assume default tables no good for progressive or downscale mode */
839
cinfo->optimize_coding = TRUE;
841
/* Initialize my private state */
842
if (transcode_only) {
843
/* no main pass in transcoding */
844
if (cinfo->optimize_coding)
845
master->pass_type = huff_opt_pass;
847
master->pass_type = output_pass;
849
/* for normal compression, first pass is always this type: */
850
master->pass_type = main_pass;
852
master->scan_number = 0;
853
master->pass_number = 0;
854
if (cinfo->optimize_coding)
855
master->total_passes = cinfo->num_scans * 2;
857
master->total_passes = cinfo->num_scans;