FFmpeg
mjpegenc.c
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1 /*
2  * MJPEG encoder
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2003 Alex Beregszaszi
5  * Copyright (c) 2003-2004 Michael Niedermayer
6  *
7  * Support for external huffman table, various fixes (AVID workaround),
8  * aspecting, new decode_frame mechanism and apple mjpeg-b support
9  * by Alex Beregszaszi
10  *
11  * This file is part of FFmpeg.
12  *
13  * FFmpeg is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * FFmpeg is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with FFmpeg; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
28 /**
29  * @file
30  * MJPEG encoder.
31  */
32 
33 #include "libavutil/pixdesc.h"
34 
35 #include "avcodec.h"
36 #include "jpegtables.h"
37 #include "mjpegenc_common.h"
38 #include "mjpegenc_huffman.h"
39 #include "mpegvideo.h"
40 #include "mjpeg.h"
41 #include "mjpegenc.h"
42 #include "profiles.h"
43 
44 static av_cold void init_uni_ac_vlc(const uint8_t huff_size_ac[256],
45  uint8_t *uni_ac_vlc_len)
46 {
47  for (int i = 0; i < 128; i++) {
48  int level = i - 64;
49  if (!level)
50  continue;
51  for (int run = 0; run < 64; run++) {
52  int len, code, nbits;
53  int alevel = FFABS(level);
54 
55  len = (run >> 4) * huff_size_ac[0xf0];
56 
57  nbits= av_log2_16bit(alevel) + 1;
58  code = ((15&run) << 4) | nbits;
59 
60  len += huff_size_ac[code] + nbits;
61 
62  uni_ac_vlc_len[UNI_AC_ENC_INDEX(run, i)] = len;
63  // We ignore EOB as its just a constant which does not change generally
64  }
65  }
66 }
67 
68 /**
69  * Encodes and outputs the entire frame in the JPEG format.
70  *
71  * @param s The MpegEncContext.
72  */
74 {
75  int nbits, code, table_id;
76  MJpegContext *m = s->mjpeg_ctx;
77  uint8_t *huff_size[4] = { m->huff_size_dc_luminance,
81  uint16_t *huff_code[4] = { m->huff_code_dc_luminance,
85  size_t total_bits = 0;
86  size_t bytes_needed;
87 
88  s->header_bits = get_bits_diff(s);
89  // Estimate the total size first
90  for (int i = 0; i < m->huff_ncode; i++) {
91  table_id = m->huff_buffer[i].table_id;
92  code = m->huff_buffer[i].code;
93  nbits = code & 0xf;
94 
95  total_bits += huff_size[table_id][code] + nbits;
96  }
97 
98  bytes_needed = (total_bits + 7) / 8;
99  ff_mpv_reallocate_putbitbuffer(s, bytes_needed, bytes_needed);
100 
101  for (int i = 0; i < m->huff_ncode; i++) {
102  table_id = m->huff_buffer[i].table_id;
103  code = m->huff_buffer[i].code;
104  nbits = code & 0xf;
105 
106  put_bits(&s->pb, huff_size[table_id][code], huff_code[table_id][code]);
107  if (nbits != 0) {
108  put_sbits(&s->pb, nbits, m->huff_buffer[i].mant);
109  }
110  }
111 
112  m->huff_ncode = 0;
113  s->i_tex_bits = get_bits_diff(s);
114 }
115 
116 /**
117  * Builds all 4 optimal Huffman tables.
118  *
119  * Uses the data stored in the JPEG buffer to compute the tables.
120  * Stores the Huffman tables in the bits_* and val_* arrays in the MJpegContext.
121  *
122  * @param m MJpegContext containing the JPEG buffer.
123  */
125 {
126  MJpegEncHuffmanContext dc_luminance_ctx;
127  MJpegEncHuffmanContext dc_chrominance_ctx;
128  MJpegEncHuffmanContext ac_luminance_ctx;
129  MJpegEncHuffmanContext ac_chrominance_ctx;
130  MJpegEncHuffmanContext *ctx[4] = { &dc_luminance_ctx,
131  &dc_chrominance_ctx,
132  &ac_luminance_ctx,
133  &ac_chrominance_ctx };
134  for (int i = 0; i < 4; i++)
136 
137  for (int i = 0; i < m->huff_ncode; i++) {
138  int table_id = m->huff_buffer[i].table_id;
139  int code = m->huff_buffer[i].code;
140 
141  ff_mjpeg_encode_huffman_increment(ctx[table_id], code);
142  }
143 
144  ff_mjpeg_encode_huffman_close(&dc_luminance_ctx,
146  m->val_dc_luminance, 12);
147  ff_mjpeg_encode_huffman_close(&dc_chrominance_ctx,
149  m->val_dc_chrominance, 12);
150  ff_mjpeg_encode_huffman_close(&ac_luminance_ctx,
152  m->val_ac_luminance, 256);
153  ff_mjpeg_encode_huffman_close(&ac_chrominance_ctx,
155  m->val_ac_chrominance, 256);
156 
160  m->val_dc_luminance);
164  m->val_dc_chrominance);
168  m->val_ac_luminance);
172  m->val_ac_chrominance);
173 }
174 
175 /**
176  * Writes the complete JPEG frame when optimal huffman tables are enabled,
177  * otherwise writes the stuffing.
178  *
179  * Header + values + stuffing.
180  *
181  * @param s The MpegEncContext.
182  * @return int Error code, 0 if successful.
183  */
185 {
186  PutBitContext *pbc = &s->pb;
187  int mb_y = s->mb_y - !s->mb_x;
188  int ret;
189  MJpegContext *m;
190 
191  m = s->mjpeg_ctx;
192 
193  if (s->huffman == HUFFMAN_TABLE_OPTIMAL) {
195 
196  // Replace the VLCs with the optimal ones.
197  // The default ones may be used for trellis during quantization.
204 
208  }
209 
210  ret = ff_mpv_reallocate_putbitbuffer(s, put_bits_count(&s->pb) / 8 + 100,
211  put_bits_count(&s->pb) / 4 + 1000);
212  if (ret < 0) {
213  av_log(s->avctx, AV_LOG_ERROR, "Buffer reallocation failed\n");
214  goto fail;
215  }
216 
217  ff_mjpeg_escape_FF(pbc, s->esc_pos);
218 
219  if ((s->avctx->active_thread_type & FF_THREAD_SLICE) && mb_y < s->mb_height - 1)
220  put_marker(pbc, RST0 + (mb_y&7));
221  s->esc_pos = put_bits_count(pbc) >> 3;
222 
223 fail:
224  for (int i = 0; i < 3; i++)
225  s->last_dc[i] = 128 << s->intra_dc_precision;
226 
227  return ret;
228 }
229 
231 {
232  MJpegContext *m = s->mjpeg_ctx;
233  size_t num_mbs, num_blocks, num_codes;
234  int blocks_per_mb;
235 
236  // We need to init this here as the mjpeg init is called before the common init,
237  s->mb_width = (s->width + 15) / 16;
238  s->mb_height = (s->height + 15) / 16;
239 
240  switch (s->chroma_format) {
241  case CHROMA_420: blocks_per_mb = 6; break;
242  case CHROMA_422: blocks_per_mb = 8; break;
243  case CHROMA_444: blocks_per_mb = 12; break;
244  default: av_assert0(0);
245  };
246 
247  // Make sure we have enough space to hold this frame.
248  num_mbs = s->mb_width * s->mb_height;
249  num_blocks = num_mbs * blocks_per_mb;
250  num_codes = num_blocks * 64;
251 
252  m->huff_buffer = av_malloc_array(num_codes, sizeof(MJpegHuffmanCode));
253  if (!m->huff_buffer)
254  return AVERROR(ENOMEM);
255  return 0;
256 }
257 
259 {
260  MJpegContext *m;
261 
263 
264  if (s->width > 65500 || s->height > 65500) {
265  av_log(s, AV_LOG_ERROR, "JPEG does not support resolutions above 65500x65500\n");
266  return AVERROR(EINVAL);
267  }
268 
269  m = av_mallocz(sizeof(MJpegContext));
270  if (!m)
271  return AVERROR(ENOMEM);
272 
273  s->min_qcoeff=-1023;
274  s->max_qcoeff= 1023;
275 
276  // Build default Huffman tables.
277  // These may be overwritten later with more optimal Huffman tables, but
278  // they are needed at least right now for some processes like trellis.
295 
302 
303  // Buffers start out empty.
304  m->huff_ncode = 0;
305  s->mjpeg_ctx = m;
306 
308  return alloc_huffman(s);
309 
310  return 0;
311 }
312 
314 {
316  av_freep(&s->mjpeg_ctx);
317 }
318 
319 /**
320  * Add code and table_id to the JPEG buffer.
321  *
322  * @param s The MJpegContext which contains the JPEG buffer.
323  * @param table_id Which Huffman table the code belongs to.
324  * @param code The encoded exponent of the coefficients and the run-bits.
325  */
326 static inline void ff_mjpeg_encode_code(MJpegContext *s, uint8_t table_id, int code)
327 {
329  c->table_id = table_id;
330  c->code = code;
331 }
332 
333 /**
334  * Add the coefficient's data to the JPEG buffer.
335  *
336  * @param s The MJpegContext which contains the JPEG buffer.
337  * @param table_id Which Huffman table the code belongs to.
338  * @param val The coefficient.
339  * @param run The run-bits.
340  */
341 static void ff_mjpeg_encode_coef(MJpegContext *s, uint8_t table_id, int val, int run)
342 {
343  int mant, code;
344 
345  if (val == 0) {
346  av_assert0(run == 0);
347  ff_mjpeg_encode_code(s, table_id, 0);
348  } else {
349  mant = val;
350  if (val < 0) {
351  val = -val;
352  mant--;
353  }
354 
355  code = (run << 4) | (av_log2_16bit(val) + 1);
356 
357  s->huff_buffer[s->huff_ncode].mant = mant;
358  ff_mjpeg_encode_code(s, table_id, code);
359  }
360 }
361 
362 /**
363  * Add the block's data into the JPEG buffer.
364  *
365  * @param s The MJpegEncContext that contains the JPEG buffer.
366  * @param block The block.
367  * @param n The block's index or number.
368  */
369 static void record_block(MpegEncContext *s, int16_t *block, int n)
370 {
371  int i, j, table_id;
372  int component, dc, last_index, val, run;
373  MJpegContext *m = s->mjpeg_ctx;
374 
375  /* DC coef */
376  component = (n <= 3 ? 0 : (n&1) + 1);
377  table_id = (n <= 3 ? 0 : 1);
378  dc = block[0]; /* overflow is impossible */
379  val = dc - s->last_dc[component];
380 
381  ff_mjpeg_encode_coef(m, table_id, val, 0);
382 
383  s->last_dc[component] = dc;
384 
385  /* AC coefs */
386 
387  run = 0;
388  last_index = s->block_last_index[n];
389  table_id |= 2;
390 
391  for(i=1;i<=last_index;i++) {
392  j = s->intra_scantable.permutated[i];
393  val = block[j];
394 
395  if (val == 0) {
396  run++;
397  } else {
398  while (run >= 16) {
399  ff_mjpeg_encode_code(m, table_id, 0xf0);
400  run -= 16;
401  }
402  ff_mjpeg_encode_coef(m, table_id, val, run);
403  run = 0;
404  }
405  }
406 
407  /* output EOB only if not already 64 values */
408  if (last_index < 63 || run != 0)
409  ff_mjpeg_encode_code(m, table_id, 0);
410 }
411 
412 static void encode_block(MpegEncContext *s, int16_t *block, int n)
413 {
414  int mant, nbits, code, i, j;
415  int component, dc, run, last_index, val;
416  MJpegContext *m = s->mjpeg_ctx;
417  uint8_t *huff_size_ac;
418  uint16_t *huff_code_ac;
419 
420  /* DC coef */
421  component = (n <= 3 ? 0 : (n&1) + 1);
422  dc = block[0]; /* overflow is impossible */
423  val = dc - s->last_dc[component];
424  if (n < 4) {
426  huff_size_ac = m->huff_size_ac_luminance;
427  huff_code_ac = m->huff_code_ac_luminance;
428  } else {
430  huff_size_ac = m->huff_size_ac_chrominance;
431  huff_code_ac = m->huff_code_ac_chrominance;
432  }
433  s->last_dc[component] = dc;
434 
435  /* AC coefs */
436 
437  run = 0;
438  last_index = s->block_last_index[n];
439  for(i=1;i<=last_index;i++) {
440  j = s->intra_scantable.permutated[i];
441  val = block[j];
442  if (val == 0) {
443  run++;
444  } else {
445  while (run >= 16) {
446  put_bits(&s->pb, huff_size_ac[0xf0], huff_code_ac[0xf0]);
447  run -= 16;
448  }
449  mant = val;
450  if (val < 0) {
451  val = -val;
452  mant--;
453  }
454 
455  nbits= av_log2_16bit(val) + 1;
456  code = (run << 4) | nbits;
457 
458  put_bits(&s->pb, huff_size_ac[code], huff_code_ac[code]);
459 
460  put_sbits(&s->pb, nbits, mant);
461  run = 0;
462  }
463  }
464 
465  /* output EOB only if not already 64 values */
466  if (last_index < 63 || run != 0)
467  put_bits(&s->pb, huff_size_ac[0], huff_code_ac[0]);
468 }
469 
470 void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[12][64])
471 {
472  int i;
473  if (s->huffman == HUFFMAN_TABLE_OPTIMAL) {
474  if (s->chroma_format == CHROMA_444) {
475  record_block(s, block[0], 0);
476  record_block(s, block[2], 2);
477  record_block(s, block[4], 4);
478  record_block(s, block[8], 8);
479  record_block(s, block[5], 5);
480  record_block(s, block[9], 9);
481 
482  if (16*s->mb_x+8 < s->width) {
483  record_block(s, block[1], 1);
484  record_block(s, block[3], 3);
485  record_block(s, block[6], 6);
486  record_block(s, block[10], 10);
487  record_block(s, block[7], 7);
488  record_block(s, block[11], 11);
489  }
490  } else {
491  for(i=0;i<5;i++) {
492  record_block(s, block[i], i);
493  }
494  if (s->chroma_format == CHROMA_420) {
495  record_block(s, block[5], 5);
496  } else {
497  record_block(s, block[6], 6);
498  record_block(s, block[5], 5);
499  record_block(s, block[7], 7);
500  }
501  }
502  } else {
503  if (s->chroma_format == CHROMA_444) {
504  encode_block(s, block[0], 0);
505  encode_block(s, block[2], 2);
506  encode_block(s, block[4], 4);
507  encode_block(s, block[8], 8);
508  encode_block(s, block[5], 5);
509  encode_block(s, block[9], 9);
510 
511  if (16*s->mb_x+8 < s->width) {
512  encode_block(s, block[1], 1);
513  encode_block(s, block[3], 3);
514  encode_block(s, block[6], 6);
515  encode_block(s, block[10], 10);
516  encode_block(s, block[7], 7);
517  encode_block(s, block[11], 11);
518  }
519  } else {
520  for(i=0;i<5;i++) {
521  encode_block(s, block[i], i);
522  }
523  if (s->chroma_format == CHROMA_420) {
524  encode_block(s, block[5], 5);
525  } else {
526  encode_block(s, block[6], 6);
527  encode_block(s, block[5], 5);
528  encode_block(s, block[7], 7);
529  }
530  }
531 
532  s->i_tex_bits += get_bits_diff(s);
533  }
534 }
535 
536 #if CONFIG_AMV_ENCODER
537 // maximum over s->mjpeg_vsample[i]
538 #define V_MAX 2
539 static int amv_encode_picture(AVCodecContext *avctx, AVPacket *pkt,
540  const AVFrame *pic_arg, int *got_packet)
541 {
542  MpegEncContext *s = avctx->priv_data;
543  AVFrame *pic;
544  int i, ret;
545  int chroma_h_shift, chroma_v_shift;
546 
547  av_pix_fmt_get_chroma_sub_sample(avctx->pix_fmt, &chroma_h_shift, &chroma_v_shift);
548 
549  if ((avctx->height & 15) && avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) {
550  av_log(avctx, AV_LOG_ERROR,
551  "Heights which are not a multiple of 16 might fail with some decoders, "
552  "use vstrict=-1 / -strict -1 to use %d anyway.\n", avctx->height);
553  av_log(avctx, AV_LOG_WARNING, "If you have a device that plays AMV videos, please test if videos "
554  "with such heights work with it and report your findings to ffmpeg-devel@ffmpeg.org\n");
555  return AVERROR_EXPERIMENTAL;
556  }
557 
558  pic = av_frame_clone(pic_arg);
559  if (!pic)
560  return AVERROR(ENOMEM);
561  //picture should be flipped upside-down
562  for(i=0; i < 3; i++) {
563  int vsample = i ? 2 >> chroma_v_shift : 2;
564  pic->data[i] += pic->linesize[i] * (vsample * s->height / V_MAX - 1);
565  pic->linesize[i] *= -1;
566  }
567  ret = ff_mpv_encode_picture(avctx, pkt, pic, got_packet);
568  av_frame_free(&pic);
569  return ret;
570 }
571 #endif
572 
573 #define OFFSET(x) offsetof(MpegEncContext, x)
574 #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
575 static const AVOption options[] = {
577 { "pred", "Prediction method", OFFSET(pred), AV_OPT_TYPE_INT, { .i64 = 1 }, 1, 3, VE, "pred" },
578  { "left", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN, INT_MAX, VE, "pred" },
579  { "plane", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 2 }, INT_MIN, INT_MAX, VE, "pred" },
580  { "median", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 3 }, INT_MIN, INT_MAX, VE, "pred" },
581 { "huffman", "Huffman table strategy", OFFSET(huffman), AV_OPT_TYPE_INT, { .i64 = HUFFMAN_TABLE_OPTIMAL }, 0, NB_HUFFMAN_TABLE_OPTION - 1, VE, "huffman" },
582  { "default", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = HUFFMAN_TABLE_DEFAULT }, INT_MIN, INT_MAX, VE, "huffman" },
583  { "optimal", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = HUFFMAN_TABLE_OPTIMAL }, INT_MIN, INT_MAX, VE, "huffman" },
584 { NULL},
585 };
586 
587 #if CONFIG_MJPEG_ENCODER
588 static const AVClass mjpeg_class = {
589  .class_name = "mjpeg encoder",
590  .item_name = av_default_item_name,
591  .option = options,
592  .version = LIBAVUTIL_VERSION_INT,
593 };
594 
596  .name = "mjpeg",
597  .long_name = NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),
598  .type = AVMEDIA_TYPE_VIDEO,
599  .id = AV_CODEC_ID_MJPEG,
600  .priv_data_size = sizeof(MpegEncContext),
602  .encode2 = ff_mpv_encode_picture,
603  .close = ff_mpv_encode_end,
606  .pix_fmts = (const enum AVPixelFormat[]) {
608  },
609  .priv_class = &mjpeg_class,
611 };
612 #endif
613 
614 #if CONFIG_AMV_ENCODER
615 static const AVClass amv_class = {
616  .class_name = "amv encoder",
617  .item_name = av_default_item_name,
618  .option = options,
619  .version = LIBAVUTIL_VERSION_INT,
620 };
621 
623  .name = "amv",
624  .long_name = NULL_IF_CONFIG_SMALL("AMV Video"),
625  .type = AVMEDIA_TYPE_VIDEO,
626  .id = AV_CODEC_ID_AMV,
627  .priv_data_size = sizeof(MpegEncContext),
629  .encode2 = amv_encode_picture,
630  .close = ff_mpv_encode_end,
632  .pix_fmts = (const enum AVPixelFormat[]) {
634  },
635  .priv_class = &amv_class,
636 };
637 #endif
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:48
#define NULL
Definition: coverity.c:32
Holds JPEG frame data and Huffman table data.
Definition: mjpegenc.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:314
AVOption.
Definition: opt.h:248
static void ff_mjpeg_encode_coef(MJpegContext *s, uint8_t table_id, int val, int run)
Add the coefficient&#39;s data to the JPEG buffer.
Definition: mjpegenc.c:341
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:260
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:218
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
uint16_t chroma_intra_matrix[64]
Definition: mpegvideo.h:301
MJPEG encoder.
#define FF_MPV_COMMON_OPTS
Definition: mpegvideo.h:619
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:741
int min_qcoeff
minimum encodable coefficient
Definition: mpegvideo.h:308
mpegvideo header.
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
av_cold int ff_mjpeg_encode_init(MpegEncContext *s)
Definition: mjpegenc.c:258
uint8_t permutated[64]
Definition: idctdsp.h:33
uint8_t run
Definition: svq3.c:205
static AVPacket pkt
uint8_t * intra_ac_vlc_length
Definition: mpegvideo.h:311
#define UNI_AC_ENC_INDEX(run, level)
Definition: mpegvideo.h:318
int av_log2_16bit(unsigned v)
Definition: intmath.c:31
AVCodec.
Definition: codec.h:190
MJPEG encoder and decoder.
uint16_t huff_code_dc_chrominance[12]
DC chrominance Huffman table codes.
Definition: mjpegenc.h:64
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:40
The exact code depends on how similar the blocks are and how related they are to the block
uint16_t huff_code_ac_luminance[256]
AC luminance Huffman table codes.
Definition: mjpegenc.h:67
uint8_t
#define av_cold
Definition: attributes.h:88
uint8_t val_ac_luminance[256]
AC luminance Huffman values.
Definition: mjpegenc.h:84
static void encode_block(MpegEncContext *s, int16_t *block, int n)
Definition: mjpegenc.c:412
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
uint8_t val_dc_chrominance[12]
DC chrominance Huffman values.
Definition: mjpegenc.h:80
uint8_t uni_chroma_ac_vlc_len[64 *64 *2]
Storage for AC chrominance VLC (in MpegEncContext)
Definition: mjpegenc.h:74
const uint8_t avpriv_mjpeg_bits_dc_luminance[17]
Definition: jpegtables.c:65
#define CHROMA_420
Definition: mpegvideo.h:486
int intra_dc_precision
Definition: mpegvideo.h:467
void ff_mjpeg_build_huffman_codes(uint8_t *huff_size, uint16_t *huff_code, const uint8_t *bits_table, const uint8_t *val_table)
planar YUV 4:2:2, 16bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV422P and setting col...
Definition: pixfmt.h:79
uint8_t huff_size_dc_chrominance[12]
DC chrominance Huffman table size.
Definition: mjpegenc.h:63
void ff_mjpeg_encode_huffman_close(MJpegEncHuffmanContext *s, uint8_t bits[17], uint8_t val[], int max_nval)
Produces a Huffman encoding with a given input.
int mb_height
number of MBs horizontally & vertically
Definition: mpegvideo.h:129
Use the default Huffman tables.
Definition: mjpegenc.h:96
int max_qcoeff
maximum encodable coefficient
Definition: mpegvideo.h:309
#define CHROMA_444
Definition: mpegvideo.h:488
#define av_log(a,...)
#define FF_COMPLIANCE_UNOFFICIAL
Allow unofficial extensions.
Definition: avcodec.h:1600
uint8_t table_id
The Huffman table id associated with the data.
Definition: mjpegenc.h:51
static int get_bits_diff(MpegEncContext *s)
Definition: mpegvideo.h:757
uint16_t huff_code_ac_chrominance[256]
AC chrominance Huffman table codes.
Definition: mjpegenc.h:69
int slice_context_count
number of used thread_contexts
Definition: mpegvideo.h:156
uint8_t huff_size_ac_luminance[256]
AC luminance Huffman table size.
Definition: mjpegenc.h:66
uint16_t mant
The mantissa.
Definition: mjpegenc.h:53
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
static void mjpeg_build_optimal_huffman(MJpegContext *m)
Builds all 4 optimal Huffman tables.
Definition: mjpegenc.c:124
int last_dc[3]
last DC values for MPEG-1
Definition: mpegvideo.h:185
const uint8_t avpriv_mjpeg_bits_dc_chrominance[17]
Definition: jpegtables.c:70
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
int av_pix_fmt_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift)
Utility function to access log2_chroma_w log2_chroma_h from the pixel format AVPixFmtDescriptor.
Definition: pixdesc.c:2601
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:115
int active_thread_type
Which multithreading methods are in use by the codec.
Definition: avcodec.h:1787
static void record_block(MpegEncContext *s, int16_t *block, int n)
Add the block&#39;s data into the JPEG buffer.
Definition: mjpegenc.c:369
uint8_t * intra_chroma_ac_vlc_length
Definition: mpegvideo.h:313
uint8_t huff_size_ac_chrominance[256]
AC chrominance Huffman table size.
Definition: mjpegenc.h:68
const char * name
Name of the codec implementation.
Definition: codec.h:197
uint8_t bits_dc_luminance[17]
DC luminance Huffman bits.
Definition: mjpegenc.h:77
#define fail()
Definition: checkasm.h:133
#define AV_CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: codec.h:106
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:83
int ff_mpv_reallocate_putbitbuffer(MpegEncContext *s, size_t threshold, size_t size_increase)
uint8_t * intra_ac_vlc_last_length
Definition: mpegvideo.h:312
static void put_marker(PutBitContext *p, enum JpegMarker code)
Definition: mjpegenc.h:101
#define CHROMA_422
Definition: mpegvideo.h:487
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting col...
Definition: pixfmt.h:78
uint8_t val_ac_chrominance[256]
AC chrominance Huffman values.
Definition: mjpegenc.h:86
AVFormatContext * ctx
Definition: movenc.c:48
uint8_t uni_ac_vlc_len[64 *64 *2]
Storage for AC luminance VLC (in MpegEncContext)
Definition: mjpegenc.h:72
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
#define s(width, name)
Definition: cbs_vp9.c:257
#define FF_THREAD_SLICE
Decode more than one part of a single frame at once.
Definition: avcodec.h:1780
void ff_mjpeg_escape_FF(PutBitContext *pb, int start)
int block_last_index[12]
last non zero coefficient in block
Definition: mpegvideo.h:86
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:540
#define AVERROR_EXPERIMENTAL
Requested feature is flagged experimental. Set strict_std_compliance if you really want to use it...
Definition: error.h:72
Compute and use optimal Huffman tables.
Definition: mjpegenc.h:97
static const float pred[4]
Definition: siprdata.h:259
struct MJpegContext * mjpeg_ctx
Definition: mpegvideo.h:424
#define AV_CODEC_CAP_SLICE_THREADS
Codec supports slice-based (or partition-based) multithreading.
Definition: codec.h:110
#define OFFSET(x)
Definition: mjpegenc.c:573
static void ff_mjpeg_encode_code(MJpegContext *s, uint8_t table_id, int code)
Add code and table_id to the JPEG buffer.
Definition: mjpegenc.c:326
Buffer of JPEG frame data.
Definition: mjpegenc.h:49
void ff_mjpeg_encode_dc(PutBitContext *pb, int val, uint8_t *huff_size, uint16_t *huff_code)
Libavcodec external API header.
static void ff_mjpeg_encode_huffman_increment(MJpegEncHuffmanContext *s, uint8_t val)
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:345
static int alloc_huffman(MpegEncContext *s)
Definition: mjpegenc.c:230
uint8_t * intra_chroma_ac_vlc_last_length
Definition: mpegvideo.h:314
main external API structure.
Definition: avcodec.h:531
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2]...the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so...,+,-,+,-,+,+,-,+,-,+,...hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32-hcoeff[1]-hcoeff[2]-...a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2}an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||.........intra?||||:Block01:yes no||||:Block02:.................||||:Block03::y DC::ref index:||||:Block04::cb DC::motion x:||||.........:cr DC::motion y:||||.................|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------------------------------|||Y subbands||Cb subbands||Cr subbands||||------||------||------|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||------||------||------||||------||------||------|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||------||------||------||||------||------||------|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||------||------||------||||------||------||------|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------------------------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction------------|\Dequantization-------------------\||Reference frames|\IDWT|--------------|Motion\|||Frame 0||Frame 1||Compensation.OBMC v-------|--------------|--------------.\------> Frame n output Frame Frame<----------------------------------/|...|-------------------Range Coder:============Binary Range Coder:-------------------The implemented range coder is an adapted version based upon"Range encoding: an algorithm for removing redundancy from a digitised message."by G.N.N.Martin.The symbols encoded by the Snow range coder are bits(0|1).The associated probabilities are not fix but change depending on the symbol mix seen so far.bit seen|new state---------+-----------------------------------------------0|256-state_transition_table[256-old_state];1|state_transition_table[old_state];state_transition_table={0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:-------------------------FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1.the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled top and top right vectors is used as motion vector prediction the used motion vector is the sum of the predictor and(mvx_diff, mvy_diff)*mv_scale Intra DC Prediction block[y][x] dc[1]
Definition: snow.txt:400
ScanTable intra_scantable
Definition: mpegvideo.h:91
int height
picture size. must be a multiple of 16
Definition: mpegvideo.h:100
int ff_mpv_encode_init(AVCodecContext *avctx)
#define VE
Definition: mjpegenc.c:574
const uint8_t avpriv_mjpeg_val_dc[12]
Definition: jpegtables.c:67
Describe the class of an AVClass context structure.
Definition: log.h:67
uint8_t bits_ac_chrominance[17]
AC chrominance Huffman bits.
Definition: mjpegenc.h:85
av_cold void ff_mjpeg_encode_close(MpegEncContext *s)
Definition: mjpegenc.c:313
const uint8_t avpriv_mjpeg_bits_ac_chrominance[17]
Definition: jpegtables.c:99
void ff_mjpeg_encode_picture_header(AVCodecContext *avctx, PutBitContext *pb, ScanTable *intra_scantable, int pred, uint16_t luma_intra_matrix[64], uint16_t chroma_intra_matrix[64])
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:303
const uint8_t avpriv_mjpeg_val_ac_chrominance[]
Definition: jpegtables.c:102
Huffman table generation for MJPEG encoder.
and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some it can consider them to be part of the FIFO and delay acknowledging a status change accordingly Example code
uint8_t val_dc_luminance[12]
DC luminance Huffman values.
Definition: mjpegenc.h:78
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:328
uint8_t level
Definition: svq3.c:206
MpegEncContext.
Definition: mpegvideo.h:81
struct AVCodecContext * avctx
Definition: mpegvideo.h:98
uint16_t huff_code_dc_luminance[12]
DC luminance Huffman table codes.
Definition: mjpegenc.h:62
PutBitContext pb
bit output
Definition: mpegvideo.h:151
uint8_t bits_dc_chrominance[17]
DC chrominance Huffman bits.
Definition: mjpegenc.h:79
const AVProfile ff_mjpeg_profiles[]
Definition: profiles.c:169
uint8_t huff_size_dc_luminance[12]
DC luminance Huffman table size.
Definition: mjpegenc.h:61
uint8_t bits_ac_luminance[17]
AC luminance Huffman bits.
Definition: mjpegenc.h:83
uint8_t code
The exponent.
Definition: mjpegenc.h:52
static av_cold void init_uni_ac_vlc(const uint8_t huff_size_ac[256], uint8_t *uni_ac_vlc_len)
Definition: mjpegenc.c:44
size_t huff_ncode
Number of current entries in the buffer.
Definition: mjpegenc.h:88
planar YUV 4:4:4, 24bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV444P and setting col...
Definition: pixfmt.h:80
int ff_mpv_encode_end(AVCodecContext *avctx)
const uint8_t avpriv_mjpeg_bits_ac_luminance[17]
Definition: jpegtables.c:73
void * priv_data
Definition: avcodec.h:558
int len
const uint8_t avpriv_mjpeg_val_ac_luminance[]
Definition: jpegtables.c:75
void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[12][64])
Definition: mjpegenc.c:470
static void mjpeg_encode_picture_frame(MpegEncContext *s)
Encodes and outputs the entire frame in the JPEG format.
Definition: mjpegenc.c:73
AVCodec ff_amv_encoder
uint16_t intra_matrix[64]
matrix transmitted in the bitstream
Definition: mpegvideo.h:300
#define av_freep(p)
#define av_malloc_array(a, b)
MJpegHuffmanCode * huff_buffer
Buffer for Huffman code values.
Definition: mjpegenc.h:89
void ff_mjpeg_encode_huffman_init(MJpegEncHuffmanContext *s)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
int ff_mpv_encode_picture(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
AVCodec ff_mjpeg_encoder
Definition: mjpeg.h:61
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
static double val(void *priv, double ch)
Definition: aeval.c:76
This structure stores compressed data.
Definition: packet.h:340
int ff_mjpeg_encode_stuffing(MpegEncContext *s)
Writes the complete JPEG frame when optimal huffman tables are enabled, otherwise writes the stuffing...
Definition: mjpegenc.c:184
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1596
int i
Definition: input.c:407
static const AVOption options[]
Definition: mjpegenc.c:575