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comparison mupdf-source/thirdparty/libjpeg/jcmarker.c @ 2:b50eed0cc0ef upstream

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ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. The directory name has changed: no version number in the expanded directory now.
author Franz Glasner <fzglas.hg@dom66.de>
date Mon, 15 Sep 2025 11:43:07 +0200
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1:1d09e1dec1d9 2:b50eed0cc0ef
1 /*
2 * jcmarker.c
3 *
4 * Copyright (C) 1991-1998, Thomas G. Lane.
5 * Modified 2003-2019 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 routines to write JPEG datastream markers.
10 */
11
12 #define JPEG_INTERNALS
13 #include "jinclude.h"
14 #include "jpeglib.h"
15
16
17 typedef enum { /* JPEG marker codes */
18 M_SOF0 = 0xc0,
19 M_SOF1 = 0xc1,
20 M_SOF2 = 0xc2,
21 M_SOF3 = 0xc3,
22
23 M_SOF5 = 0xc5,
24 M_SOF6 = 0xc6,
25 M_SOF7 = 0xc7,
26
27 M_JPG = 0xc8,
28 M_SOF9 = 0xc9,
29 M_SOF10 = 0xca,
30 M_SOF11 = 0xcb,
31
32 M_SOF13 = 0xcd,
33 M_SOF14 = 0xce,
34 M_SOF15 = 0xcf,
35
36 M_DHT = 0xc4,
37
38 M_DAC = 0xcc,
39
40 M_RST0 = 0xd0,
41 M_RST1 = 0xd1,
42 M_RST2 = 0xd2,
43 M_RST3 = 0xd3,
44 M_RST4 = 0xd4,
45 M_RST5 = 0xd5,
46 M_RST6 = 0xd6,
47 M_RST7 = 0xd7,
48
49 M_SOI = 0xd8,
50 M_EOI = 0xd9,
51 M_SOS = 0xda,
52 M_DQT = 0xdb,
53 M_DNL = 0xdc,
54 M_DRI = 0xdd,
55 M_DHP = 0xde,
56 M_EXP = 0xdf,
57
58 M_APP0 = 0xe0,
59 M_APP1 = 0xe1,
60 M_APP2 = 0xe2,
61 M_APP3 = 0xe3,
62 M_APP4 = 0xe4,
63 M_APP5 = 0xe5,
64 M_APP6 = 0xe6,
65 M_APP7 = 0xe7,
66 M_APP8 = 0xe8,
67 M_APP9 = 0xe9,
68 M_APP10 = 0xea,
69 M_APP11 = 0xeb,
70 M_APP12 = 0xec,
71 M_APP13 = 0xed,
72 M_APP14 = 0xee,
73 M_APP15 = 0xef,
74
75 M_JPG0 = 0xf0,
76 M_JPG8 = 0xf8,
77 M_JPG13 = 0xfd,
78 M_COM = 0xfe,
79
80 M_TEM = 0x01,
81
82 M_ERROR = 0x100
83 } JPEG_MARKER;
84
85
86 /* Private state */
87
88 typedef struct {
89 struct jpeg_marker_writer pub; /* public fields */
90
91 unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */
92 } my_marker_writer;
93
94 typedef my_marker_writer * my_marker_ptr;
95
96
97 /*
98 * Basic output routines.
99 *
100 * Note that we do not support suspension while writing a marker.
101 * Therefore, an application using suspension must ensure that there is
102 * enough buffer space for the initial markers (typ. 600-700 bytes) before
103 * calling jpeg_start_compress, and enough space to write the trailing EOI
104 * (a few bytes) before calling jpeg_finish_compress. Multipass compression
105 * modes are not supported at all with suspension, so those two are the only
106 * points where markers will be written.
107 */
108
109 LOCAL(void)
110 emit_byte (j_compress_ptr cinfo, int val)
111 /* Emit a byte */
112 {
113 struct jpeg_destination_mgr * dest = cinfo->dest;
114
115 *(dest->next_output_byte)++ = (JOCTET) val;
116 if (--dest->free_in_buffer == 0) {
117 if (! (*dest->empty_output_buffer) (cinfo))
118 ERREXIT(cinfo, JERR_CANT_SUSPEND);
119 }
120 }
121
122
123 LOCAL(void)
124 emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark)
125 /* Emit a marker code */
126 {
127 emit_byte(cinfo, 0xFF);
128 emit_byte(cinfo, (int) mark);
129 }
130
131
132 LOCAL(void)
133 emit_2bytes (j_compress_ptr cinfo, int value)
134 /* Emit a 2-byte integer; these are always MSB first in JPEG files */
135 {
136 emit_byte(cinfo, (value >> 8) & 0xFF);
137 emit_byte(cinfo, value & 0xFF);
138 }
139
140
141 /*
142 * Routines to write specific marker types.
143 */
144
145 LOCAL(int)
146 emit_dqt (j_compress_ptr cinfo, int index)
147 /* Emit a DQT marker */
148 /* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */
149 {
150 JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index];
151 int prec;
152 int i;
153
154 if (qtbl == NULL)
155 ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index);
156
157 prec = 0;
158 for (i = 0; i <= cinfo->lim_Se; i++) {
159 if (qtbl->quantval[cinfo->natural_order[i]] > 255)
160 prec = 1;
161 }
162
163 if (! qtbl->sent_table) {
164 emit_marker(cinfo, M_DQT);
165
166 emit_2bytes(cinfo,
167 prec ? cinfo->lim_Se * 2 + 2 + 1 + 2 : cinfo->lim_Se + 1 + 1 + 2);
168
169 emit_byte(cinfo, index + (prec<<4));
170
171 for (i = 0; i <= cinfo->lim_Se; i++) {
172 /* The table entries must be emitted in zigzag order. */
173 unsigned int qval = qtbl->quantval[cinfo->natural_order[i]];
174 if (prec)
175 emit_byte(cinfo, (int) (qval >> 8));
176 emit_byte(cinfo, (int) (qval & 0xFF));
177 }
178
179 qtbl->sent_table = TRUE;
180 }
181
182 return prec;
183 }
184
185
186 LOCAL(void)
187 emit_dht (j_compress_ptr cinfo, int index, boolean is_ac)
188 /* Emit a DHT marker */
189 {
190 JHUFF_TBL * htbl;
191 int length, i;
192
193 if (is_ac) {
194 htbl = cinfo->ac_huff_tbl_ptrs[index];
195 index += 0x10; /* output index has AC bit set */
196 } else {
197 htbl = cinfo->dc_huff_tbl_ptrs[index];
198 }
199
200 if (htbl == NULL)
201 ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index);
202
203 if (! htbl->sent_table) {
204 emit_marker(cinfo, M_DHT);
205
206 length = 0;
207 for (i = 1; i <= 16; i++)
208 length += htbl->bits[i];
209
210 emit_2bytes(cinfo, length + 2 + 1 + 16);
211 emit_byte(cinfo, index);
212
213 for (i = 1; i <= 16; i++)
214 emit_byte(cinfo, htbl->bits[i]);
215
216 for (i = 0; i < length; i++)
217 emit_byte(cinfo, htbl->huffval[i]);
218
219 htbl->sent_table = TRUE;
220 }
221 }
222
223
224 LOCAL(void)
225 emit_dac (j_compress_ptr cinfo)
226 /* Emit a DAC marker */
227 /* Since the useful info is so small, we want to emit all the tables in */
228 /* one DAC marker. Therefore this routine does its own scan of the table. */
229 {
230 #ifdef C_ARITH_CODING_SUPPORTED
231 char dc_in_use[NUM_ARITH_TBLS];
232 char ac_in_use[NUM_ARITH_TBLS];
233 int length, i;
234 jpeg_component_info *compptr;
235
236 for (i = 0; i < NUM_ARITH_TBLS; i++)
237 dc_in_use[i] = ac_in_use[i] = 0;
238
239 for (i = 0; i < cinfo->comps_in_scan; i++) {
240 compptr = cinfo->cur_comp_info[i];
241 /* DC needs no table for refinement scan */
242 if (cinfo->Ss == 0 && cinfo->Ah == 0)
243 dc_in_use[compptr->dc_tbl_no] = 1;
244 /* AC needs no table when not present */
245 if (cinfo->Se)
246 ac_in_use[compptr->ac_tbl_no] = 1;
247 }
248
249 length = 0;
250 for (i = 0; i < NUM_ARITH_TBLS; i++)
251 length += dc_in_use[i] + ac_in_use[i];
252
253 if (length) {
254 emit_marker(cinfo, M_DAC);
255
256 emit_2bytes(cinfo, length*2 + 2);
257
258 for (i = 0; i < NUM_ARITH_TBLS; i++) {
259 if (dc_in_use[i]) {
260 emit_byte(cinfo, i);
261 emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4));
262 }
263 if (ac_in_use[i]) {
264 emit_byte(cinfo, i + 0x10);
265 emit_byte(cinfo, cinfo->arith_ac_K[i]);
266 }
267 }
268 }
269 #endif /* C_ARITH_CODING_SUPPORTED */
270 }
271
272
273 LOCAL(void)
274 emit_dri (j_compress_ptr cinfo)
275 /* Emit a DRI marker */
276 {
277 emit_marker(cinfo, M_DRI);
278
279 emit_2bytes(cinfo, 4); /* fixed length */
280
281 emit_2bytes(cinfo, (int) cinfo->restart_interval);
282 }
283
284
285 LOCAL(void)
286 emit_lse_ict (j_compress_ptr cinfo)
287 /* Emit an LSE inverse color transform specification marker */
288 {
289 /* Support only 1 transform */
290 if (cinfo->color_transform != JCT_SUBTRACT_GREEN ||
291 cinfo->num_components < 3)
292 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
293
294 emit_marker(cinfo, M_JPG8);
295
296 emit_2bytes(cinfo, 24); /* fixed length */
297
298 emit_byte(cinfo, 0x0D); /* ID inverse transform specification */
299 emit_2bytes(cinfo, MAXJSAMPLE); /* MAXTRANS */
300 emit_byte(cinfo, 3); /* Nt=3 */
301 emit_byte(cinfo, cinfo->comp_info[1].component_id);
302 emit_byte(cinfo, cinfo->comp_info[0].component_id);
303 emit_byte(cinfo, cinfo->comp_info[2].component_id);
304 emit_byte(cinfo, 0x80); /* F1: CENTER1=1, NORM1=0 */
305 emit_2bytes(cinfo, 0); /* A(1,1)=0 */
306 emit_2bytes(cinfo, 0); /* A(1,2)=0 */
307 emit_byte(cinfo, 0); /* F2: CENTER2=0, NORM2=0 */
308 emit_2bytes(cinfo, 1); /* A(2,1)=1 */
309 emit_2bytes(cinfo, 0); /* A(2,2)=0 */
310 emit_byte(cinfo, 0); /* F3: CENTER3=0, NORM3=0 */
311 emit_2bytes(cinfo, 1); /* A(3,1)=1 */
312 emit_2bytes(cinfo, 0); /* A(3,2)=0 */
313 }
314
315
316 LOCAL(void)
317 emit_sof (j_compress_ptr cinfo, JPEG_MARKER code)
318 /* Emit a SOF marker */
319 {
320 int ci;
321 jpeg_component_info *compptr;
322
323 emit_marker(cinfo, code);
324
325 emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */
326
327 /* Make sure image isn't bigger than SOF field can handle */
328 if ((long) cinfo->jpeg_height > 65535L ||
329 (long) cinfo->jpeg_width > 65535L)
330 ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535);
331
332 emit_byte(cinfo, cinfo->data_precision);
333 emit_2bytes(cinfo, (int) cinfo->jpeg_height);
334 emit_2bytes(cinfo, (int) cinfo->jpeg_width);
335
336 emit_byte(cinfo, cinfo->num_components);
337
338 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
339 ci++, compptr++) {
340 emit_byte(cinfo, compptr->component_id);
341 emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor);
342 emit_byte(cinfo, compptr->quant_tbl_no);
343 }
344 }
345
346
347 LOCAL(void)
348 emit_sos (j_compress_ptr cinfo)
349 /* Emit a SOS marker */
350 {
351 int i, td, ta;
352 jpeg_component_info *compptr;
353
354 emit_marker(cinfo, M_SOS);
355
356 emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */
357
358 emit_byte(cinfo, cinfo->comps_in_scan);
359
360 for (i = 0; i < cinfo->comps_in_scan; i++) {
361 compptr = cinfo->cur_comp_info[i];
362 emit_byte(cinfo, compptr->component_id);
363
364 /* We emit 0 for unused field(s); this is recommended by the P&M text
365 * but does not seem to be specified in the standard.
366 */
367
368 /* DC needs no table for refinement scan */
369 td = cinfo->Ss == 0 && cinfo->Ah == 0 ? compptr->dc_tbl_no : 0;
370 /* AC needs no table when not present */
371 ta = cinfo->Se ? compptr->ac_tbl_no : 0;
372
373 emit_byte(cinfo, (td << 4) + ta);
374 }
375
376 emit_byte(cinfo, cinfo->Ss);
377 emit_byte(cinfo, cinfo->Se);
378 emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al);
379 }
380
381
382 LOCAL(void)
383 emit_pseudo_sos (j_compress_ptr cinfo)
384 /* Emit a pseudo SOS marker */
385 {
386 emit_marker(cinfo, M_SOS);
387
388 emit_2bytes(cinfo, 2 + 1 + 3); /* length */
389
390 emit_byte(cinfo, 0); /* Ns */
391
392 emit_byte(cinfo, 0); /* Ss */
393 emit_byte(cinfo, cinfo->block_size * cinfo->block_size - 1); /* Se */
394 emit_byte(cinfo, 0); /* Ah/Al */
395 }
396
397
398 LOCAL(void)
399 emit_jfif_app0 (j_compress_ptr cinfo)
400 /* Emit a JFIF-compliant APP0 marker */
401 {
402 /*
403 * Length of APP0 block (2 bytes)
404 * Block ID (4 bytes - ASCII "JFIF")
405 * Zero byte (1 byte to terminate the ID string)
406 * Version Major, Minor (2 bytes - major first)
407 * Units (1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm)
408 * Xdpu (2 bytes - dots per unit horizontal)
409 * Ydpu (2 bytes - dots per unit vertical)
410 * Thumbnail X size (1 byte)
411 * Thumbnail Y size (1 byte)
412 */
413
414 emit_marker(cinfo, M_APP0);
415
416 emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */
417
418 emit_byte(cinfo, 0x4A); /* Identifier: ASCII "JFIF" */
419 emit_byte(cinfo, 0x46);
420 emit_byte(cinfo, 0x49);
421 emit_byte(cinfo, 0x46);
422 emit_byte(cinfo, 0);
423 emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */
424 emit_byte(cinfo, cinfo->JFIF_minor_version);
425 emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */
426 emit_2bytes(cinfo, (int) cinfo->X_density);
427 emit_2bytes(cinfo, (int) cinfo->Y_density);
428 emit_byte(cinfo, 0); /* No thumbnail image */
429 emit_byte(cinfo, 0);
430 }
431
432
433 LOCAL(void)
434 emit_adobe_app14 (j_compress_ptr cinfo)
435 /* Emit an Adobe APP14 marker */
436 {
437 /*
438 * Length of APP14 block (2 bytes)
439 * Block ID (5 bytes - ASCII "Adobe")
440 * Version Number (2 bytes - currently 100)
441 * Flags0 (2 bytes - currently 0)
442 * Flags1 (2 bytes - currently 0)
443 * Color transform (1 byte)
444 *
445 * Although Adobe TN 5116 mentions Version = 101, all the Adobe files
446 * now in circulation seem to use Version = 100, so that's what we write.
447 *
448 * We write the color transform byte as 1 if the JPEG color space is
449 * YCbCr, 2 if it's YCCK, 0 otherwise. Adobe's definition has to do with
450 * whether the encoder performed a transformation, which is pretty useless.
451 */
452
453 emit_marker(cinfo, M_APP14);
454
455 emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */
456
457 emit_byte(cinfo, 0x41); /* Identifier: ASCII "Adobe" */
458 emit_byte(cinfo, 0x64);
459 emit_byte(cinfo, 0x6F);
460 emit_byte(cinfo, 0x62);
461 emit_byte(cinfo, 0x65);
462 emit_2bytes(cinfo, 100); /* Version */
463 emit_2bytes(cinfo, 0); /* Flags0 */
464 emit_2bytes(cinfo, 0); /* Flags1 */
465 switch (cinfo->jpeg_color_space) {
466 case JCS_YCbCr:
467 emit_byte(cinfo, 1); /* Color transform = 1 */
468 break;
469 case JCS_YCCK:
470 emit_byte(cinfo, 2); /* Color transform = 2 */
471 break;
472 default:
473 emit_byte(cinfo, 0); /* Color transform = 0 */
474 }
475 }
476
477
478 /*
479 * These routines allow writing an arbitrary marker with parameters.
480 * The only intended use is to emit COM or APPn markers after calling
481 * write_file_header and before calling write_frame_header.
482 * Other uses are not guaranteed to produce desirable results.
483 * Counting the parameter bytes properly is the caller's responsibility.
484 */
485
486 METHODDEF(void)
487 write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
488 /* Emit an arbitrary marker header */
489 {
490 if (datalen > (unsigned int) 65533) /* safety check */
491 ERREXIT(cinfo, JERR_BAD_LENGTH);
492
493 emit_marker(cinfo, (JPEG_MARKER) marker);
494
495 emit_2bytes(cinfo, (int) (datalen + 2)); /* total length */
496 }
497
498 METHODDEF(void)
499 write_marker_byte (j_compress_ptr cinfo, int val)
500 /* Emit one byte of marker parameters following write_marker_header */
501 {
502 emit_byte(cinfo, val);
503 }
504
505
506 /*
507 * Write datastream header.
508 * This consists of an SOI and optional APPn markers.
509 * We recommend use of the JFIF marker, but not the Adobe marker,
510 * when using YCbCr or grayscale data. The JFIF marker is also used
511 * for other standard JPEG colorspaces. The Adobe marker is helpful
512 * to distinguish RGB, CMYK, and YCCK colorspaces.
513 * Note that an application can write additional header markers after
514 * jpeg_start_compress returns.
515 */
516
517 METHODDEF(void)
518 write_file_header (j_compress_ptr cinfo)
519 {
520 my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
521
522 emit_marker(cinfo, M_SOI); /* first the SOI */
523
524 /* SOI is defined to reset restart interval to 0 */
525 marker->last_restart_interval = 0;
526
527 if (cinfo->write_JFIF_header) /* next an optional JFIF APP0 */
528 emit_jfif_app0(cinfo);
529 if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */
530 emit_adobe_app14(cinfo);
531 }
532
533
534 /*
535 * Write frame header.
536 * This consists of DQT and SOFn markers,
537 * a conditional LSE marker and a conditional pseudo SOS marker.
538 * Note that we do not emit the SOF until we have emitted the DQT(s).
539 * This avoids compatibility problems with incorrect implementations that
540 * try to error-check the quant table numbers as soon as they see the SOF.
541 */
542
543 METHODDEF(void)
544 write_frame_header (j_compress_ptr cinfo)
545 {
546 int ci, prec;
547 boolean is_baseline;
548 jpeg_component_info *compptr;
549
550 /* Emit DQT for each quantization table.
551 * Note that emit_dqt() suppresses any duplicate tables.
552 */
553 prec = 0;
554 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
555 ci++, compptr++) {
556 prec += emit_dqt(cinfo, compptr->quant_tbl_no);
557 }
558 /* now prec is nonzero iff there are any 16-bit quant tables. */
559
560 /* Check for a non-baseline specification.
561 * Note we assume that Huffman table numbers won't be changed later.
562 */
563 if (cinfo->arith_code || cinfo->progressive_mode ||
564 cinfo->data_precision != 8 || cinfo->block_size != DCTSIZE) {
565 is_baseline = FALSE;
566 } else {
567 is_baseline = TRUE;
568 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
569 ci++, compptr++) {
570 if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1)
571 is_baseline = FALSE;
572 }
573 if (prec && is_baseline) {
574 is_baseline = FALSE;
575 /* If it's baseline except for quantizer size, warn the user */
576 TRACEMS(cinfo, 0, JTRC_16BIT_TABLES);
577 }
578 }
579
580 /* Emit the proper SOF marker */
581 if (cinfo->arith_code) {
582 if (cinfo->progressive_mode)
583 emit_sof(cinfo, M_SOF10); /* SOF code for progressive arithmetic */
584 else
585 emit_sof(cinfo, M_SOF9); /* SOF code for sequential arithmetic */
586 } else {
587 if (cinfo->progressive_mode)
588 emit_sof(cinfo, M_SOF2); /* SOF code for progressive Huffman */
589 else if (is_baseline)
590 emit_sof(cinfo, M_SOF0); /* SOF code for baseline implementation */
591 else
592 emit_sof(cinfo, M_SOF1); /* SOF code for non-baseline Huffman file */
593 }
594
595 /* Check to emit LSE inverse color transform specification marker */
596 if (cinfo->color_transform)
597 emit_lse_ict(cinfo);
598
599 /* Check to emit pseudo SOS marker */
600 if (cinfo->progressive_mode && cinfo->block_size != DCTSIZE)
601 emit_pseudo_sos(cinfo);
602 }
603
604
605 /*
606 * Write scan header.
607 * This consists of DHT or DAC markers, optional DRI, and SOS.
608 * Compressed data will be written following the SOS.
609 */
610
611 METHODDEF(void)
612 write_scan_header (j_compress_ptr cinfo)
613 {
614 my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
615 int i;
616 jpeg_component_info *compptr;
617
618 if (cinfo->arith_code) {
619 /* Emit arith conditioning info. We may have some duplication
620 * if the file has multiple scans, but it's so small it's hardly
621 * worth worrying about.
622 */
623 emit_dac(cinfo);
624 } else {
625 /* Emit Huffman tables.
626 * Note that emit_dht() suppresses any duplicate tables.
627 */
628 for (i = 0; i < cinfo->comps_in_scan; i++) {
629 compptr = cinfo->cur_comp_info[i];
630 /* DC needs no table for refinement scan */
631 if (cinfo->Ss == 0 && cinfo->Ah == 0)
632 emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
633 /* AC needs no table when not present */
634 if (cinfo->Se)
635 emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
636 }
637 }
638
639 /* Emit DRI if required --- note that DRI value could change for each scan.
640 * We avoid wasting space with unnecessary DRIs, however.
641 */
642 if (cinfo->restart_interval != marker->last_restart_interval) {
643 emit_dri(cinfo);
644 marker->last_restart_interval = cinfo->restart_interval;
645 }
646
647 emit_sos(cinfo);
648 }
649
650
651 /*
652 * Write datastream trailer.
653 */
654
655 METHODDEF(void)
656 write_file_trailer (j_compress_ptr cinfo)
657 {
658 emit_marker(cinfo, M_EOI);
659 }
660
661
662 /*
663 * Write an abbreviated table-specification datastream.
664 * This consists of SOI, DQT and DHT tables, and EOI.
665 * Any table that is defined and not marked sent_table = TRUE will be
666 * emitted. Note that all tables will be marked sent_table = TRUE at exit.
667 */
668
669 METHODDEF(void)
670 write_tables_only (j_compress_ptr cinfo)
671 {
672 int i;
673
674 emit_marker(cinfo, M_SOI);
675
676 for (i = 0; i < NUM_QUANT_TBLS; i++) {
677 if (cinfo->quant_tbl_ptrs[i] != NULL)
678 (void) emit_dqt(cinfo, i);
679 }
680
681 if (! cinfo->arith_code) {
682 for (i = 0; i < NUM_HUFF_TBLS; i++) {
683 if (cinfo->dc_huff_tbl_ptrs[i] != NULL)
684 emit_dht(cinfo, i, FALSE);
685 if (cinfo->ac_huff_tbl_ptrs[i] != NULL)
686 emit_dht(cinfo, i, TRUE);
687 }
688 }
689
690 emit_marker(cinfo, M_EOI);
691 }
692
693
694 /*
695 * Initialize the marker writer module.
696 */
697
698 GLOBAL(void)
699 jinit_marker_writer (j_compress_ptr cinfo)
700 {
701 my_marker_ptr marker;
702
703 /* Create the subobject */
704 marker = (my_marker_ptr) (*cinfo->mem->alloc_small)
705 ((j_common_ptr) cinfo, JPOOL_IMAGE, SIZEOF(my_marker_writer));
706 cinfo->marker = &marker->pub;
707 /* Initialize method pointers */
708 marker->pub.write_file_header = write_file_header;
709 marker->pub.write_frame_header = write_frame_header;
710 marker->pub.write_scan_header = write_scan_header;
711 marker->pub.write_file_trailer = write_file_trailer;
712 marker->pub.write_tables_only = write_tables_only;
713 marker->pub.write_marker_header = write_marker_header;
714 marker->pub.write_marker_byte = write_marker_byte;
715 /* Initialize private state */
716 marker->last_restart_interval = 0;
717 }