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1
/*
2
 * jcmarker.c
3
 *
4
 * Copyright (C) 1991-1998, Thomas G. Lane.
5
 * This file is part of the Independent JPEG Group's software.
6
 * For conditions of distribution and use, see the accompanying README file.
7
 *
8
 * This file contains routines to write JPEG datastream markers.
9
 */
10

11
#define JPEG_INTERNALS
12
#include "jinclude.h"
13
#include "jpeglib.h"
14

15

16
typedef enum {			/* JPEG marker codes */
17
  M_SOF0  = 0xc0,
18
  M_SOF1  = 0xc1,
19
  M_SOF2  = 0xc2,
20
  M_SOF3  = 0xc3,
21
  
22
  M_SOF5  = 0xc5,
23
  M_SOF6  = 0xc6,
24
  M_SOF7  = 0xc7,
25
  
26
  M_JPG   = 0xc8,
27
  M_SOF9  = 0xc9,
28
  M_SOF10 = 0xca,
29
  M_SOF11 = 0xcb,
30
  
31
  M_SOF13 = 0xcd,
32
  M_SOF14 = 0xce,
33
  M_SOF15 = 0xcf,
34
  
35
  M_DHT   = 0xc4,
36
  
37
  M_DAC   = 0xcc,
38
  
39
  M_RST0  = 0xd0,
40
  M_RST1  = 0xd1,
41
  M_RST2  = 0xd2,
42
  M_RST3  = 0xd3,
43
  M_RST4  = 0xd4,
44
  M_RST5  = 0xd5,
45
  M_RST6  = 0xd6,
46
  M_RST7  = 0xd7,
47
  
48
  M_SOI   = 0xd8,
49
  M_EOI   = 0xd9,
50
  M_SOS   = 0xda,
51
  M_DQT   = 0xdb,
52
  M_DNL   = 0xdc,
53
  M_DRI   = 0xdd,
54
  M_DHP   = 0xde,
55
  M_EXP   = 0xdf,
56
  
57
  M_APP0  = 0xe0,
58
  M_APP1  = 0xe1,
59
  M_APP2  = 0xe2,
60
  M_APP3  = 0xe3,
61
  M_APP4  = 0xe4,
62
  M_APP5  = 0xe5,
63
  M_APP6  = 0xe6,
64
  M_APP7  = 0xe7,
65
  M_APP8  = 0xe8,
66
  M_APP9  = 0xe9,
67
  M_APP10 = 0xea,
68
  M_APP11 = 0xeb,
69
  M_APP12 = 0xec,
70
  M_APP13 = 0xed,
71
  M_APP14 = 0xee,
72
  M_APP15 = 0xef,
73
  
74
  M_JPG0  = 0xf0,
75
  M_JPG13 = 0xfd,
76
  M_COM   = 0xfe,
77
  
78
  M_TEM   = 0x01,
79
  
80
  M_ERROR = 0x100
81
} JPEG_MARKER;
82

83

84
/* Private state */
85

86
typedef struct {
87
  struct jpeg_marker_writer pub; /* public fields */
88

89
  unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */
90
} my_marker_writer;
91

92
typedef my_marker_writer * my_marker_ptr;
93

94

95
/*
96
 * Basic output routines.
97
 *
98
 * Note that we do not support suspension while writing a marker.
99
 * Therefore, an application using suspension must ensure that there is
100
 * enough buffer space for the initial markers (typ. 600-700 bytes) before
101
 * calling jpeg_start_compress, and enough space to write the trailing EOI
102
 * (a few bytes) before calling jpeg_finish_compress.  Multipass compression
103
 * modes are not supported at all with suspension, so those two are the only
104
 * points where markers will be written.
105
 */
106

107
LOCAL(void)
108
emit_byte (j_compress_ptr cinfo, int val)
109
/* Emit a byte */
110
{
111
  struct jpeg_destination_mgr * dest = cinfo->dest;
112

113
  *(dest->next_output_byte)++ = (JOCTET) val;
114
  if (--dest->free_in_buffer == 0) {
115
    if (! (*dest->empty_output_buffer) (cinfo))
116
      ERREXIT(cinfo, JERR_CANT_SUSPEND);
117
  }
118
}
119

120

121
LOCAL(void)
122
emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark)
123
/* Emit a marker code */
124
{
125
  emit_byte(cinfo, 0xFF);
126
  emit_byte(cinfo, (int) mark);
127
}
128

129

130
LOCAL(void)
131
emit_2bytes (j_compress_ptr cinfo, int value)
132
/* Emit a 2-byte integer; these are always MSB first in JPEG files */
133
{
134
  emit_byte(cinfo, (value >> 8) & 0xFF);
135
  emit_byte(cinfo, value & 0xFF);
136
}
137

138

139
/*
140
 * Routines to write specific marker types.
141
 */
142

143
LOCAL(int)
144
emit_dqt (j_compress_ptr cinfo, int index)
145
/* Emit a DQT marker */
146
/* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */
147
{
148
  JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index];
149
  int prec;
150
  int i;
151

152
  if (qtbl == NULL)
153
    ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index);
154

155
  prec = 0;
156
  for (i = 0; i < DCTSIZE2; i++) {
157
    if (qtbl->quantval[i] > 255)
158
      prec = 1;
159
  }
160

161
  if (! qtbl->sent_table) {
162
    emit_marker(cinfo, M_DQT);
163

164
    emit_2bytes(cinfo, prec ? DCTSIZE2*2 + 1 + 2 : DCTSIZE2 + 1 + 2);
165

166
    emit_byte(cinfo, index + (prec<<4));
167

168
    for (i = 0; i < DCTSIZE2; i++) {
169
      /* The table entries must be emitted in zigzag order. */
170
      unsigned int qval = qtbl->quantval[jpeg_natural_order[i]];
171
      if (prec)
172
	emit_byte(cinfo, (int) (qval >> 8));
173
      emit_byte(cinfo, (int) (qval & 0xFF));
174
    }
175

176
    qtbl->sent_table = TRUE;
177
  }
178

179
  return prec;
180
}
181

182

183
LOCAL(void)
184
emit_dht (j_compress_ptr cinfo, int index, boolean is_ac)
185
/* Emit a DHT marker */
186
{
187
  JHUFF_TBL * htbl;
188
  int length, i;
189
  
190
  if (is_ac) {
191
    htbl = cinfo->ac_huff_tbl_ptrs[index];
192
    index += 0x10;		/* output index has AC bit set */
193
  } else {
194
    htbl = cinfo->dc_huff_tbl_ptrs[index];
195
  }
196

197
  if (htbl == NULL)
198
    ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index);
199
  
200
  if (! htbl->sent_table) {
201
    emit_marker(cinfo, M_DHT);
202
    
203
    length = 0;
204
    for (i = 1; i <= 16; i++)
205
      length += htbl->bits[i];
206
    
207
    emit_2bytes(cinfo, length + 2 + 1 + 16);
208
    emit_byte(cinfo, index);
209
    
210
    for (i = 1; i <= 16; i++)
211
      emit_byte(cinfo, htbl->bits[i]);
212
    
213
    for (i = 0; i < length; i++)
214
      emit_byte(cinfo, htbl->huffval[i]);
215
    
216
    htbl->sent_table = TRUE;
217
  }
218
}
219

220

221
LOCAL(void)
222
emit_dac (j_compress_ptr cinfo)
223
/* Emit a DAC marker */
224
/* Since the useful info is so small, we want to emit all the tables in */
225
/* one DAC marker.  Therefore this routine does its own scan of the table. */
226
{
227
#ifdef C_ARITH_CODING_SUPPORTED
228
  char dc_in_use[NUM_ARITH_TBLS];
229
  char ac_in_use[NUM_ARITH_TBLS];
230
  int length, i;
231
  jpeg_component_info *compptr;
232
  
233
  for (i = 0; i < NUM_ARITH_TBLS; i++)
234
    dc_in_use[i] = ac_in_use[i] = 0;
235
  
236
  for (i = 0; i < cinfo->comps_in_scan; i++) {
237
    compptr = cinfo->cur_comp_info[i];
238
    dc_in_use[compptr->dc_tbl_no] = 1;
239
    ac_in_use[compptr->ac_tbl_no] = 1;
240
  }
241
  
242
  length = 0;
243
  for (i = 0; i < NUM_ARITH_TBLS; i++)
244
    length += dc_in_use[i] + ac_in_use[i];
245
  
246
  emit_marker(cinfo, M_DAC);
247
  
248
  emit_2bytes(cinfo, length*2 + 2);
249
  
250
  for (i = 0; i < NUM_ARITH_TBLS; i++) {
251
    if (dc_in_use[i]) {
252
      emit_byte(cinfo, i);
253
      emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4));
254
    }
255
    if (ac_in_use[i]) {
256
      emit_byte(cinfo, i + 0x10);
257
      emit_byte(cinfo, cinfo->arith_ac_K[i]);
258
    }
259
  }
260
#endif /* C_ARITH_CODING_SUPPORTED */
261
}
262

263

264
LOCAL(void)
265
emit_dri (j_compress_ptr cinfo)
266
/* Emit a DRI marker */
267
{
268
  emit_marker(cinfo, M_DRI);
269
  
270
  emit_2bytes(cinfo, 4);	/* fixed length */
271

272
  emit_2bytes(cinfo, (int) cinfo->restart_interval);
273
}
274

275

276
LOCAL(void)
277
emit_sof (j_compress_ptr cinfo, JPEG_MARKER code)
278
/* Emit a SOF marker */
279
{
280
  int ci;
281
  jpeg_component_info *compptr;
282
  
283
  emit_marker(cinfo, code);
284
  
285
  emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */
286

287
  /* Make sure image isn't bigger than SOF field can handle */
288
  if ((long) cinfo->image_height > 65535L ||
289
      (long) cinfo->image_width > 65535L)
290
    ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535);
291

292
  emit_byte(cinfo, cinfo->data_precision);
293
  emit_2bytes(cinfo, (int) cinfo->image_height);
294
  emit_2bytes(cinfo, (int) cinfo->image_width);
295

296
  emit_byte(cinfo, cinfo->num_components);
297

298
  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
299
       ci++, compptr++) {
300
    emit_byte(cinfo, compptr->component_id);
301
    emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor);
302
    emit_byte(cinfo, compptr->quant_tbl_no);
303
  }
304
}
305

306

307
LOCAL(void)
308
emit_sos (j_compress_ptr cinfo)
309
/* Emit a SOS marker */
310
{
311
  int i, td, ta;
312
  jpeg_component_info *compptr;
313
  
314
  emit_marker(cinfo, M_SOS);
315
  
316
  emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */
317
  
318
  emit_byte(cinfo, cinfo->comps_in_scan);
319
  
320
  for (i = 0; i < cinfo->comps_in_scan; i++) {
321
    compptr = cinfo->cur_comp_info[i];
322
    emit_byte(cinfo, compptr->component_id);
323
    td = compptr->dc_tbl_no;
324
    ta = compptr->ac_tbl_no;
325
    if (cinfo->progressive_mode) {
326
      /* Progressive mode: only DC or only AC tables are used in one scan;
327
       * furthermore, Huffman coding of DC refinement uses no table at all.
328
       * We emit 0 for unused field(s); this is recommended by the P&M text
329
       * but does not seem to be specified in the standard.
330
       */
331
      if (cinfo->Ss == 0) {
332
	ta = 0;			/* DC scan */
333
	if (cinfo->Ah != 0 && !cinfo->arith_code)
334
	  td = 0;		/* no DC table either */
335
      } else {
336
	td = 0;			/* AC scan */
337
      }
338
    }
339
    emit_byte(cinfo, (td << 4) + ta);
340
  }
341

342
  emit_byte(cinfo, cinfo->Ss);
343
  emit_byte(cinfo, cinfo->Se);
344
  emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al);
345
}
346

347

348
LOCAL(void)
349
emit_jfif_app0 (j_compress_ptr cinfo)
350
/* Emit a JFIF-compliant APP0 marker */
351
{
352
  /*
353
   * Length of APP0 block	(2 bytes)
354
   * Block ID			(4 bytes - ASCII "JFIF")
355
   * Zero byte			(1 byte to terminate the ID string)
356
   * Version Major, Minor	(2 bytes - major first)
357
   * Units			(1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm)
358
   * Xdpu			(2 bytes - dots per unit horizontal)
359
   * Ydpu			(2 bytes - dots per unit vertical)
360
   * Thumbnail X size		(1 byte)
361
   * Thumbnail Y size		(1 byte)
362
   */
363
  
364
  emit_marker(cinfo, M_APP0);
365
  
366
  emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */
367

368
  emit_byte(cinfo, 0x4A);	/* Identifier: ASCII "JFIF" */
369
  emit_byte(cinfo, 0x46);
370
  emit_byte(cinfo, 0x49);
371
  emit_byte(cinfo, 0x46);
372
  emit_byte(cinfo, 0);
373
  emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */
374
  emit_byte(cinfo, cinfo->JFIF_minor_version);
375
  emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */
376
  emit_2bytes(cinfo, (int) cinfo->X_density);
377
  emit_2bytes(cinfo, (int) cinfo->Y_density);
378
  emit_byte(cinfo, 0);		/* No thumbnail image */
379
  emit_byte(cinfo, 0);
380
}
381

382

383
LOCAL(void)
384
emit_adobe_app14 (j_compress_ptr cinfo)
385
/* Emit an Adobe APP14 marker */
386
{
387
  /*
388
   * Length of APP14 block	(2 bytes)
389
   * Block ID			(5 bytes - ASCII "Adobe")
390
   * Version Number		(2 bytes - currently 100)
391
   * Flags0			(2 bytes - currently 0)
392
   * Flags1			(2 bytes - currently 0)
393
   * Color transform		(1 byte)
394
   *
395
   * Although Adobe TN 5116 mentions Version = 101, all the Adobe files
396
   * now in circulation seem to use Version = 100, so that's what we write.
397
   *
398
   * We write the color transform byte as 1 if the JPEG color space is
399
   * YCbCr, 2 if it's YCCK, 0 otherwise.  Adobe's definition has to do with
400
   * whether the encoder performed a transformation, which is pretty useless.
401
   */
402
  
403
  emit_marker(cinfo, M_APP14);
404
  
405
  emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */
406

407
  emit_byte(cinfo, 0x41);	/* Identifier: ASCII "Adobe" */
408
  emit_byte(cinfo, 0x64);
409
  emit_byte(cinfo, 0x6F);
410
  emit_byte(cinfo, 0x62);
411
  emit_byte(cinfo, 0x65);
412
  emit_2bytes(cinfo, 100);	/* Version */
413
  emit_2bytes(cinfo, 0);	/* Flags0 */
414
  emit_2bytes(cinfo, 0);	/* Flags1 */
415
  switch (cinfo->jpeg_color_space) {
416
  case JCS_YCbCr:
417
    emit_byte(cinfo, 1);	/* Color transform = 1 */
418
    break;
419
  case JCS_YCCK:
420
    emit_byte(cinfo, 2);	/* Color transform = 2 */
421
    break;
422
  default:
423
    emit_byte(cinfo, 0);	/* Color transform = 0 */
424
    break;
425
  }
426
}
427

428

429
/*
430
 * These routines allow writing an arbitrary marker with parameters.
431
 * The only intended use is to emit COM or APPn markers after calling
432
 * write_file_header and before calling write_frame_header.
433
 * Other uses are not guaranteed to produce desirable results.
434
 * Counting the parameter bytes properly is the caller's responsibility.
435
 */
436

437
METHODDEF(void)
438
write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
439
/* Emit an arbitrary marker header */
440
{
441
  if (datalen > (unsigned int) 65533)		/* safety check */
442
    ERREXIT(cinfo, JERR_BAD_LENGTH);
443

444
  emit_marker(cinfo, (JPEG_MARKER) marker);
445

446
  emit_2bytes(cinfo, (int) (datalen + 2));	/* total length */
447
}
448

449
METHODDEF(void)
450
write_marker_byte (j_compress_ptr cinfo, int val)
451
/* Emit one byte of marker parameters following write_marker_header */
452
{
453
  emit_byte(cinfo, val);
454
}
455

456

457
/*
458
 * Write datastream header.
459
 * This consists of an SOI and optional APPn markers.
460
 * We recommend use of the JFIF marker, but not the Adobe marker,
461
 * when using YCbCr or grayscale data.  The JFIF marker should NOT
462
 * be used for any other JPEG colorspace.  The Adobe marker is helpful
463
 * to distinguish RGB, CMYK, and YCCK colorspaces.
464
 * Note that an application can write additional header markers after
465
 * jpeg_start_compress returns.
466
 */
467

468
METHODDEF(void)
469
write_file_header (j_compress_ptr cinfo)
470
{
471
  my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
472

473
  emit_marker(cinfo, M_SOI);	/* first the SOI */
474

475
  /* SOI is defined to reset restart interval to 0 */
476
  marker->last_restart_interval = 0;
477

478
  if (cinfo->write_JFIF_header)	/* next an optional JFIF APP0 */
479
    emit_jfif_app0(cinfo);
480
  if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */
481
    emit_adobe_app14(cinfo);
482
}
483

484

485
/*
486
 * Write frame header.
487
 * This consists of DQT and SOFn markers.
488
 * Note that we do not emit the SOF until we have emitted the DQT(s).
489
 * This avoids compatibility problems with incorrect implementations that
490
 * try to error-check the quant table numbers as soon as they see the SOF.
491
 */
492

493
METHODDEF(void)
494
write_frame_header (j_compress_ptr cinfo)
495
{
496
  int ci, prec;
497
  boolean is_baseline;
498
  jpeg_component_info *compptr;
499
  
500
  /* Emit DQT for each quantization table.
501
   * Note that emit_dqt() suppresses any duplicate tables.
502
   */
503
  prec = 0;
504
  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
505
       ci++, compptr++) {
506
    prec += emit_dqt(cinfo, compptr->quant_tbl_no);
507
  }
508
  /* now prec is nonzero iff there are any 16-bit quant tables. */
509

510
  /* Check for a non-baseline specification.
511
   * Note we assume that Huffman table numbers won't be changed later.
512
   */
513
  if (cinfo->arith_code || cinfo->progressive_mode ||
514
      cinfo->data_precision != 8) {
515
    is_baseline = FALSE;
516
  } else {
517
    is_baseline = TRUE;
518
    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
519
	 ci++, compptr++) {
520
      if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1)
521
	is_baseline = FALSE;
522
    }
523
    if (prec && is_baseline) {
524
      is_baseline = FALSE;
525
      /* If it's baseline except for quantizer size, warn the user */
526
      TRACEMS(cinfo, 0, JTRC_16BIT_TABLES);
527
    }
528
  }
529

530
  /* Emit the proper SOF marker */
531
  if (cinfo->arith_code) {
532
    emit_sof(cinfo, M_SOF9);	/* SOF code for arithmetic coding */
533
  } else {
534
    if (cinfo->progressive_mode)
535
      emit_sof(cinfo, M_SOF2);	/* SOF code for progressive Huffman */
536
    else if (is_baseline)
537
      emit_sof(cinfo, M_SOF0);	/* SOF code for baseline implementation */
538
    else
539
      emit_sof(cinfo, M_SOF1);	/* SOF code for non-baseline Huffman file */
540
  }
541
}
542

543

544
/*
545
 * Write scan header.
546
 * This consists of DHT or DAC markers, optional DRI, and SOS.
547
 * Compressed data will be written following the SOS.
548
 */
549

550
METHODDEF(void)
551
write_scan_header (j_compress_ptr cinfo)
552
{
553
  my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
554
  int i;
555
  jpeg_component_info *compptr;
556

557
  if (cinfo->arith_code) {
558
    /* Emit arith conditioning info.  We may have some duplication
559
     * if the file has multiple scans, but it's so small it's hardly
560
     * worth worrying about.
561
     */
562
    emit_dac(cinfo);
563
  } else {
564
    /* Emit Huffman tables.
565
     * Note that emit_dht() suppresses any duplicate tables.
566
     */
567
    for (i = 0; i < cinfo->comps_in_scan; i++) {
568
      compptr = cinfo->cur_comp_info[i];
569
      if (cinfo->progressive_mode) {
570
	/* Progressive mode: only DC or only AC tables are used in one scan */
571
	if (cinfo->Ss == 0) {
572
	  if (cinfo->Ah == 0)	/* DC needs no table for refinement scan */
573
	    emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
574
	} else {
575
	  emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
576
	}
577
      } else {
578
	/* Sequential mode: need both DC and AC tables */
579
	emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
580
	emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
581
      }
582
    }
583
  }
584

585
  /* Emit DRI if required --- note that DRI value could change for each scan.
586
   * We avoid wasting space with unnecessary DRIs, however.
587
   */
588
  if (cinfo->restart_interval != marker->last_restart_interval) {
589
    emit_dri(cinfo);
590
    marker->last_restart_interval = cinfo->restart_interval;
591
  }
592

593
  emit_sos(cinfo);
594
}
595

596

597
/*
598
 * Write datastream trailer.
599
 */
600

601
METHODDEF(void)
602
write_file_trailer (j_compress_ptr cinfo)
603
{
604
  emit_marker(cinfo, M_EOI);
605
}
606

607

608
/*
609
 * Write an abbreviated table-specification datastream.
610
 * This consists of SOI, DQT and DHT tables, and EOI.
611
 * Any table that is defined and not marked sent_table = TRUE will be
612
 * emitted.  Note that all tables will be marked sent_table = TRUE at exit.
613
 */
614

615
METHODDEF(void)
616
write_tables_only (j_compress_ptr cinfo)
617
{
618
  int i;
619

620
  emit_marker(cinfo, M_SOI);
621

622
  for (i = 0; i < NUM_QUANT_TBLS; i++) {
623
    if (cinfo->quant_tbl_ptrs[i] != NULL)
624
      (void) emit_dqt(cinfo, i);
625
  }
626

627
  if (! cinfo->arith_code) {
628
    for (i = 0; i < NUM_HUFF_TBLS; i++) {
629
      if (cinfo->dc_huff_tbl_ptrs[i] != NULL)
630
	emit_dht(cinfo, i, FALSE);
631
      if (cinfo->ac_huff_tbl_ptrs[i] != NULL)
632
	emit_dht(cinfo, i, TRUE);
633
    }
634
  }
635

636
  emit_marker(cinfo, M_EOI);
637
}
638

639

640
/*
641
 * Initialize the marker writer module.
642
 */
643

644
GLOBAL(void)
645
jinit_marker_writer (j_compress_ptr cinfo)
646
{
647
  my_marker_ptr marker;
648

649
  /* Create the subobject */
650
  marker = (my_marker_ptr)
651
    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
652
				SIZEOF(my_marker_writer));
653
  cinfo->marker = (struct jpeg_marker_writer *) marker;
654
  /* Initialize method pointers */
655
  marker->pub.write_file_header = write_file_header;
656
  marker->pub.write_frame_header = write_frame_header;
657
  marker->pub.write_scan_header = write_scan_header;
658
  marker->pub.write_file_trailer = write_file_trailer;
659
  marker->pub.write_tables_only = write_tables_only;
660
  marker->pub.write_marker_header = write_marker_header;
661
  marker->pub.write_marker_byte = write_marker_byte;
662
  /* Initialize private state */
663
  marker->last_restart_interval = 0;
664
}
665

666