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mpeg12enc.c
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1 /*
2  * MPEG1/2 encoder
3  * Copyright (c) 2000,2001 Fabrice Bellard
4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * MPEG1/2 encoder
26  */
27 
28 #include "libavutil/attributes.h"
29 #include "libavutil/avassert.h"
30 #include "libavutil/log.h"
31 #include "libavutil/opt.h"
32 #include "libavutil/timecode.h"
33 #include "avcodec.h"
34 #include "bytestream.h"
35 #include "mathops.h"
36 #include "mpeg12.h"
37 #include "mpeg12data.h"
38 #include "mpegvideo.h"
39 
40 
41 static const uint8_t inv_non_linear_qscale[] = {
42  0, 2, 4, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16,
43 };
44 
45 static const uint8_t svcd_scan_offset_placeholder[] = {
46  0x10, 0x0E, 0x00, 0x80, 0x81, 0x00, 0x80,
47  0x81, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
48 };
49 
50 static uint8_t mv_penalty[MAX_FCODE + 1][MAX_MV * 2 + 1];
51 static uint8_t fcode_tab[MAX_MV * 2 + 1];
52 
53 static uint8_t uni_mpeg1_ac_vlc_len[64 * 64 * 2];
54 static uint8_t uni_mpeg2_ac_vlc_len[64 * 64 * 2];
55 
56 /* simple include everything table for dc, first byte is bits
57  * number next 3 are code */
58 static uint32_t mpeg1_lum_dc_uni[512];
59 static uint32_t mpeg1_chr_dc_uni[512];
60 
61 static uint8_t mpeg1_index_run[2][64];
62 static int8_t mpeg1_max_level[2][64];
63 
64 static av_cold void init_uni_ac_vlc(RLTable *rl, uint8_t *uni_ac_vlc_len)
65 {
66  int i;
67 
68  for (i = 0; i < 128; i++) {
69  int level = i - 64;
70  int run;
71  if (!level)
72  continue;
73  for (run = 0; run < 64; run++) {
74  int len, code;
75  int alevel = FFABS(level);
76 
77  if (alevel > rl->max_level[0][run])
78  code = 111; /* rl->n */
79  else
80  code = rl->index_run[0][run] + alevel - 1;
81 
82  if (code < 111) { /* rl->n */
83  /* length of VLC and sign */
84  len = rl->table_vlc[code][1] + 1;
85  } else {
86  len = rl->table_vlc[111 /* rl->n */][1] + 6;
87 
88  if (alevel < 128)
89  len += 8;
90  else
91  len += 16;
92  }
93 
94  uni_ac_vlc_len[UNI_AC_ENC_INDEX(run, i)] = len;
95  }
96  }
97 }
98 
99 static int find_frame_rate_index(MpegEncContext *s)
100 {
101  int i;
102  AVRational bestq = (AVRational) {0, 0};
103  AVRational ext;
104  AVRational target = av_inv_q(s->avctx->time_base);
105 
106  for (i = 1; i < 14; i++) {
107  if (s->avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL &&
108  i >= 9)
109  break;
110 
111  for (ext.num=1; ext.num <= 4; ext.num++) {
112  for (ext.den=1; ext.den <= 32; ext.den++) {
113  AVRational q = av_mul_q(ext, ff_mpeg12_frame_rate_tab[i]);
114 
115  if (s->codec_id != AV_CODEC_ID_MPEG2VIDEO && (ext.den!=1 || ext.num!=1))
116  continue;
117  if (av_gcd(ext.den, ext.num) != 1)
118  continue;
119 
120  if ( bestq.num==0
121  || av_nearer_q(target, bestq, q) < 0
122  || ext.num==1 && ext.den==1 && av_nearer_q(target, bestq, q) == 0) {
123  bestq = q;
124  s->frame_rate_index = i;
125  s->mpeg2_frame_rate_ext.num = ext.num;
126  s->mpeg2_frame_rate_ext.den = ext.den;
127  }
128  }
129  }
130  }
131 
132  if (av_cmp_q(target, bestq))
133  return -1;
134  else
135  return 0;
136 }
137 
138 static av_cold int encode_init(AVCodecContext *avctx)
139 {
140  MpegEncContext *s = avctx->priv_data;
141 
142  if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO && avctx->height > 2800)
143  avctx->thread_count = 1;
144 
145  if (ff_MPV_encode_init(avctx) < 0)
146  return -1;
147 
148  if (find_frame_rate_index(s) < 0) {
149  if (s->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {
150  av_log(avctx, AV_LOG_ERROR, "MPEG1/2 does not support %d/%d fps\n",
151  avctx->time_base.den, avctx->time_base.num);
152  return -1;
153  } else {
154  av_log(avctx, AV_LOG_INFO,
155  "MPEG1/2 does not support %d/%d fps, there may be AV sync issues\n",
156  avctx->time_base.den, avctx->time_base.num);
157  }
158  }
159 
160  if (avctx->profile == FF_PROFILE_UNKNOWN) {
161  if (avctx->level != FF_LEVEL_UNKNOWN) {
162  av_log(avctx, AV_LOG_ERROR, "Set profile and level\n");
163  return -1;
164  }
165  /* Main or 4:2:2 */
166  avctx->profile = s->chroma_format == CHROMA_420 ? 4 : 0;
167  }
168 
169  if (avctx->level == FF_LEVEL_UNKNOWN) {
170  if (avctx->profile == 0) { /* 4:2:2 */
171  if (avctx->width <= 720 && avctx->height <= 608)
172  avctx->level = 5; /* Main */
173  else
174  avctx->level = 2; /* High */
175  } else {
176  if (avctx->profile != 1 && s->chroma_format != CHROMA_420) {
177  av_log(avctx, AV_LOG_ERROR,
178  "Only High(1) and 4:2:2(0) profiles support 4:2:2 color sampling\n");
179  return -1;
180  }
181  if (avctx->width <= 720 && avctx->height <= 576)
182  avctx->level = 8; /* Main */
183  else if (avctx->width <= 1440)
184  avctx->level = 6; /* High 1440 */
185  else
186  avctx->level = 4; /* High */
187  }
188  }
189 
190  if ((avctx->width & 0xFFF) == 0 && (avctx->height & 0xFFF) == 1) {
191  av_log(avctx, AV_LOG_ERROR, "Width / Height is invalid for MPEG2\n");
192  return AVERROR(EINVAL);
193  }
194 
195  if (s->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) {
196  if ((avctx->width & 0xFFF) == 0 || (avctx->height & 0xFFF) == 0) {
197  av_log(avctx, AV_LOG_ERROR, "Width or Height are not allowed to be multiplies of 4096\n"
198  "add '-strict %d' if you want to use them anyway.\n", FF_COMPLIANCE_UNOFFICIAL);
199  return AVERROR(EINVAL);
200  }
201  }
202 
203  s->drop_frame_timecode = s->drop_frame_timecode || !!(avctx->flags2 & CODEC_FLAG2_DROP_FRAME_TIMECODE);
204  if (s->drop_frame_timecode)
205  s->tc.flags |= AV_TIMECODE_FLAG_DROPFRAME;
206  if (s->drop_frame_timecode && s->frame_rate_index != 4) {
207  av_log(avctx, AV_LOG_ERROR,
208  "Drop frame time code only allowed with 1001/30000 fps\n");
209  return -1;
210  }
211 
212  if (s->tc_opt_str) {
213  AVRational rate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
214  int ret = av_timecode_init_from_string(&s->tc, rate, s->tc_opt_str, s);
215  if (ret < 0)
216  return ret;
217  s->drop_frame_timecode = !!(s->tc.flags & AV_TIMECODE_FLAG_DROPFRAME);
218  s->avctx->timecode_frame_start = s->tc.start;
219  } else {
220  s->avctx->timecode_frame_start = 0; // default is -1
221  }
222  return 0;
223 }
224 
225 static void put_header(MpegEncContext *s, int header)
226 {
227  avpriv_align_put_bits(&s->pb);
228  put_bits(&s->pb, 16, header >> 16);
229  put_sbits(&s->pb, 16, header);
230 }
231 
232 /* put sequence header if needed */
233 static void mpeg1_encode_sequence_header(MpegEncContext *s)
234 {
235  unsigned int vbv_buffer_size, fps, v;
236  int i, constraint_parameter_flag;
237  uint64_t time_code;
238  float best_aspect_error = 1E10;
239  float aspect_ratio = av_q2d(s->avctx->sample_aspect_ratio);
240 
241  if (aspect_ratio == 0.0)
242  aspect_ratio = 1.0; // pixel aspect 1.1 (VGA)
243 
244  if (s->current_picture.f.key_frame) {
245  AVRational framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
246 
247  /* mpeg1 header repeated every gop */
248  put_header(s, SEQ_START_CODE);
249 
250  put_sbits(&s->pb, 12, s->width & 0xFFF);
251  put_sbits(&s->pb, 12, s->height & 0xFFF);
252 
253  for (i = 1; i < 15; i++) {
254  float error = aspect_ratio;
255  if (s->codec_id == AV_CODEC_ID_MPEG1VIDEO || i <= 1)
256  error -= 1.0 / ff_mpeg1_aspect[i];
257  else
258  error -= av_q2d(ff_mpeg2_aspect[i]) * s->height / s->width;
259 
260  error = FFABS(error);
261 
262  if (error < best_aspect_error) {
263  best_aspect_error = error;
264  s->aspect_ratio_info = i;
265  }
266  }
267 
268  put_bits(&s->pb, 4, s->aspect_ratio_info);
269  put_bits(&s->pb, 4, s->frame_rate_index);
270 
271  if (s->avctx->rc_max_rate) {
272  v = (s->avctx->rc_max_rate + 399) / 400;
273  if (v > 0x3ffff && s->codec_id == AV_CODEC_ID_MPEG1VIDEO)
274  v = 0x3ffff;
275  } else {
276  v = 0x3FFFF;
277  }
278 
279  if (s->avctx->rc_buffer_size)
280  vbv_buffer_size = s->avctx->rc_buffer_size;
281  else
282  /* VBV calculation: Scaled so that a VCD has the proper
283  * VBV size of 40 kilobytes */
284  vbv_buffer_size = ((20 * s->bit_rate) / (1151929 / 2)) * 8 * 1024;
285  vbv_buffer_size = (vbv_buffer_size + 16383) / 16384;
286 
287  put_sbits(&s->pb, 18, v);
288  put_bits(&s->pb, 1, 1); // marker
289  put_sbits(&s->pb, 10, vbv_buffer_size);
290 
291  constraint_parameter_flag =
292  s->width <= 768 &&
293  s->height <= 576 &&
294  s->mb_width * s->mb_height <= 396 &&
295  s->mb_width * s->mb_height * framerate.num <= 396 * 25 * framerate.den &&
296  framerate.num <= framerate.den * 30 &&
297  s->avctx->me_range &&
298  s->avctx->me_range < 128 &&
299  vbv_buffer_size <= 20 &&
300  v <= 1856000 / 400 &&
301  s->codec_id == AV_CODEC_ID_MPEG1VIDEO;
302 
303  put_bits(&s->pb, 1, constraint_parameter_flag);
304 
305  ff_write_quant_matrix(&s->pb, s->avctx->intra_matrix);
306  ff_write_quant_matrix(&s->pb, s->avctx->inter_matrix);
307 
308  if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
309  put_header(s, EXT_START_CODE);
310  put_bits(&s->pb, 4, 1); // seq ext
311 
312  put_bits(&s->pb, 1, s->avctx->profile == 0); // escx 1 for 4:2:2 profile
313 
314  put_bits(&s->pb, 3, s->avctx->profile); // profile
315  put_bits(&s->pb, 4, s->avctx->level); // level
316 
317  put_bits(&s->pb, 1, s->progressive_sequence);
318  put_bits(&s->pb, 2, s->chroma_format);
319  put_bits(&s->pb, 2, s->width >> 12);
320  put_bits(&s->pb, 2, s->height >> 12);
321  put_bits(&s->pb, 12, v >> 18); // bitrate ext
322  put_bits(&s->pb, 1, 1); // marker
323  put_bits(&s->pb, 8, vbv_buffer_size >> 10); // vbv buffer ext
324  put_bits(&s->pb, 1, s->low_delay);
325  put_bits(&s->pb, 2, s->mpeg2_frame_rate_ext.num-1); // frame_rate_ext_n
326  put_bits(&s->pb, 5, s->mpeg2_frame_rate_ext.den-1); // frame_rate_ext_d
327  }
328 
329  put_header(s, GOP_START_CODE);
330  put_bits(&s->pb, 1, s->drop_frame_timecode); // drop frame flag
331  /* time code: we must convert from the real frame rate to a
332  * fake MPEG frame rate in case of low frame rate */
333  fps = (framerate.num + framerate.den / 2) / framerate.den;
334  time_code = s->current_picture_ptr->f.coded_picture_number +
335  s->avctx->timecode_frame_start;
336 
337  s->gop_picture_number = s->current_picture_ptr->f.coded_picture_number;
338 
339  av_assert0(s->drop_frame_timecode == !!(s->tc.flags & AV_TIMECODE_FLAG_DROPFRAME));
340  if (s->drop_frame_timecode)
341  time_code = av_timecode_adjust_ntsc_framenum2(time_code, fps);
342 
343  put_bits(&s->pb, 5, (uint32_t)((time_code / (fps * 3600)) % 24));
344  put_bits(&s->pb, 6, (uint32_t)((time_code / (fps * 60)) % 60));
345  put_bits(&s->pb, 1, 1);
346  put_bits(&s->pb, 6, (uint32_t)((time_code / fps) % 60));
347  put_bits(&s->pb, 6, (uint32_t)((time_code % fps)));
348  put_bits(&s->pb, 1, !!(s->flags & CODEC_FLAG_CLOSED_GOP));
349  put_bits(&s->pb, 1, 0); // broken link
350  }
351 }
352 
353 static inline void encode_mb_skip_run(MpegEncContext *s, int run)
354 {
355  while (run >= 33) {
356  put_bits(&s->pb, 11, 0x008);
357  run -= 33;
358  }
359  put_bits(&s->pb, ff_mpeg12_mbAddrIncrTable[run][1],
360  ff_mpeg12_mbAddrIncrTable[run][0]);
361 }
362 
363 static av_always_inline void put_qscale(MpegEncContext *s)
364 {
365  if (s->q_scale_type) {
366  av_assert2(s->qscale >= 1 && s->qscale <= 12);
367  put_bits(&s->pb, 5, inv_non_linear_qscale[s->qscale]);
368  } else {
369  put_bits(&s->pb, 5, s->qscale);
370  }
371 }
372 
373 void ff_mpeg1_encode_slice_header(MpegEncContext *s)
374 {
375  if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO && s->height > 2800) {
376  put_header(s, SLICE_MIN_START_CODE + (s->mb_y & 127));
377  /* slice_vertical_position_extension */
378  put_bits(&s->pb, 3, s->mb_y >> 7);
379  } else {
380  put_header(s, SLICE_MIN_START_CODE + s->mb_y);
381  }
382  put_qscale(s);
383  /* slice extra information */
384  put_bits(&s->pb, 1, 0);
385 }
386 
387 void ff_mpeg1_encode_picture_header(MpegEncContext *s, int picture_number)
388 {
389  mpeg1_encode_sequence_header(s);
390 
391  /* mpeg1 picture header */
392  put_header(s, PICTURE_START_CODE);
393  /* temporal reference */
394 
395  // RAL: s->picture_number instead of s->fake_picture_number
396  put_bits(&s->pb, 10,
397  (s->picture_number - s->gop_picture_number) & 0x3ff);
398  put_bits(&s->pb, 3, s->pict_type);
399 
400  s->vbv_delay_ptr = s->pb.buf + put_bits_count(&s->pb) / 8;
401  put_bits(&s->pb, 16, 0xFFFF); /* vbv_delay */
402 
403  // RAL: Forward f_code also needed for B-frames
404  if (s->pict_type == AV_PICTURE_TYPE_P ||
405  s->pict_type == AV_PICTURE_TYPE_B) {
406  put_bits(&s->pb, 1, 0); /* half pel coordinates */
407  if (s->codec_id == AV_CODEC_ID_MPEG1VIDEO)
408  put_bits(&s->pb, 3, s->f_code); /* forward_f_code */
409  else
410  put_bits(&s->pb, 3, 7); /* forward_f_code */
411  }
412 
413  // RAL: Backward f_code necessary for B-frames
414  if (s->pict_type == AV_PICTURE_TYPE_B) {
415  put_bits(&s->pb, 1, 0); /* half pel coordinates */
416  if (s->codec_id == AV_CODEC_ID_MPEG1VIDEO)
417  put_bits(&s->pb, 3, s->b_code); /* backward_f_code */
418  else
419  put_bits(&s->pb, 3, 7); /* backward_f_code */
420  }
421 
422  put_bits(&s->pb, 1, 0); /* extra bit picture */
423 
424  s->frame_pred_frame_dct = 1;
425  if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
426  put_header(s, EXT_START_CODE);
427  put_bits(&s->pb, 4, 8); /* pic ext */
428  if (s->pict_type == AV_PICTURE_TYPE_P ||
429  s->pict_type == AV_PICTURE_TYPE_B) {
430  put_bits(&s->pb, 4, s->f_code);
431  put_bits(&s->pb, 4, s->f_code);
432  } else {
433  put_bits(&s->pb, 8, 255);
434  }
435  if (s->pict_type == AV_PICTURE_TYPE_B) {
436  put_bits(&s->pb, 4, s->b_code);
437  put_bits(&s->pb, 4, s->b_code);
438  } else {
439  put_bits(&s->pb, 8, 255);
440  }
441  put_bits(&s->pb, 2, s->intra_dc_precision);
442 
443  av_assert0(s->picture_structure == PICT_FRAME);
444  put_bits(&s->pb, 2, s->picture_structure);
445  if (s->progressive_sequence)
446  put_bits(&s->pb, 1, 0); /* no repeat */
447  else
448  put_bits(&s->pb, 1, s->current_picture_ptr->f.top_field_first);
449  /* XXX: optimize the generation of this flag with entropy measures */
450  s->frame_pred_frame_dct = s->progressive_sequence;
451 
452  put_bits(&s->pb, 1, s->frame_pred_frame_dct);
453  put_bits(&s->pb, 1, s->concealment_motion_vectors);
454  put_bits(&s->pb, 1, s->q_scale_type);
455  put_bits(&s->pb, 1, s->intra_vlc_format);
456  put_bits(&s->pb, 1, s->alternate_scan);
457  put_bits(&s->pb, 1, s->repeat_first_field);
458  s->progressive_frame = s->progressive_sequence;
459  /* chroma_420_type */
460  put_bits(&s->pb, 1, s->chroma_format ==
461  CHROMA_420 ? s->progressive_frame : 0);
462  put_bits(&s->pb, 1, s->progressive_frame);
463  put_bits(&s->pb, 1, 0); /* composite_display_flag */
464  }
465  if (s->scan_offset) {
466  int i;
467 
468  put_header(s, USER_START_CODE);
469  for (i = 0; i < sizeof(svcd_scan_offset_placeholder); i++)
470  put_bits(&s->pb, 8, svcd_scan_offset_placeholder[i]);
471  }
472 
473  s->mb_y = 0;
474  ff_mpeg1_encode_slice_header(s);
475 }
476 
477 static inline void put_mb_modes(MpegEncContext *s, int n, int bits,
478  int has_mv, int field_motion)
479 {
480  put_bits(&s->pb, n, bits);
481  if (!s->frame_pred_frame_dct) {
482  if (has_mv)
483  /* motion_type: frame/field */
484  put_bits(&s->pb, 2, 2 - field_motion);
485  put_bits(&s->pb, 1, s->interlaced_dct);
486  }
487 }
488 
489 // RAL: Parameter added: f_or_b_code
490 static void mpeg1_encode_motion(MpegEncContext *s, int val, int f_or_b_code)
491 {
492  if (val == 0) {
493  /* zero vector */
494  put_bits(&s->pb,
495  ff_mpeg12_mbMotionVectorTable[0][1],
496  ff_mpeg12_mbMotionVectorTable[0][0]);
497  } else {
498  int code, sign, bits;
499  int bit_size = f_or_b_code - 1;
500  int range = 1 << bit_size;
501  /* modulo encoding */
502  val = sign_extend(val, 5 + bit_size);
503 
504  if (val >= 0) {
505  val--;
506  code = (val >> bit_size) + 1;
507  bits = val & (range - 1);
508  sign = 0;
509  } else {
510  val = -val;
511  val--;
512  code = (val >> bit_size) + 1;
513  bits = val & (range - 1);
514  sign = 1;
515  }
516 
517  av_assert2(code > 0 && code <= 16);
518 
519  put_bits(&s->pb,
520  ff_mpeg12_mbMotionVectorTable[code][1],
521  ff_mpeg12_mbMotionVectorTable[code][0]);
522 
523  put_bits(&s->pb, 1, sign);
524  if (bit_size > 0)
525  put_bits(&s->pb, bit_size, bits);
526  }
527 }
528 
529 static inline void encode_dc(MpegEncContext *s, int diff, int component)
530 {
531  if (((unsigned) (diff + 255)) >= 511) {
532  int index;
533 
534  if (diff < 0) {
535  index = av_log2_16bit(-2 * diff);
536  diff--;
537  } else {
538  index = av_log2_16bit(2 * diff);
539  }
540  if (component == 0)
541  put_bits(&s->pb,
542  ff_mpeg12_vlc_dc_lum_bits[index] + index,
543  (ff_mpeg12_vlc_dc_lum_code[index] << index) +
544  (diff & ((1 << index) - 1)));
545  else
546  put_bits(&s->pb,
547  ff_mpeg12_vlc_dc_chroma_bits[index] + index,
548  (ff_mpeg12_vlc_dc_chroma_code[index] << index) +
549  (diff & ((1 << index) - 1)));
550  } else {
551  if (component == 0)
552  put_bits(&s->pb,
553  mpeg1_lum_dc_uni[diff + 255] & 0xFF,
554  mpeg1_lum_dc_uni[diff + 255] >> 8);
555  else
556  put_bits(&s->pb,
557  mpeg1_chr_dc_uni[diff + 255] & 0xFF,
558  mpeg1_chr_dc_uni[diff + 255] >> 8);
559  }
560 }
561 
562 static void mpeg1_encode_block(MpegEncContext *s, int16_t *block, int n)
563 {
564  int alevel, level, last_non_zero, dc, diff, i, j, run, last_index, sign;
565  int code, component;
566  const uint16_t (*table_vlc)[2] = ff_rl_mpeg1.table_vlc;
567 
568  last_index = s->block_last_index[n];
569 
570  /* DC coef */
571  if (s->mb_intra) {
572  component = (n <= 3 ? 0 : (n & 1) + 1);
573  dc = block[0]; /* overflow is impossible */
574  diff = dc - s->last_dc[component];
575  encode_dc(s, diff, component);
576  s->last_dc[component] = dc;
577  i = 1;
578  if (s->intra_vlc_format)
579  table_vlc = ff_rl_mpeg2.table_vlc;
580  } else {
581  /* encode the first coefficient: needs to be done here because
582  * it is handled slightly differently */
583  level = block[0];
584  if (abs(level) == 1) {
585  code = ((uint32_t)level >> 31); /* the sign bit */
586  put_bits(&s->pb, 2, code | 0x02);
587  i = 1;
588  } else {
589  i = 0;
590  last_non_zero = -1;
591  goto next_coef;
592  }
593  }
594 
595  /* now quantify & encode AC coefs */
596  last_non_zero = i - 1;
597 
598  for (; i <= last_index; i++) {
599  j = s->intra_scantable.permutated[i];
600  level = block[j];
601 
602 next_coef:
603  /* encode using VLC */
604  if (level != 0) {
605  run = i - last_non_zero - 1;
606 
607  alevel = level;
608  MASK_ABS(sign, alevel);
609  sign &= 1;
610 
611  if (alevel <= mpeg1_max_level[0][run]) {
612  code = mpeg1_index_run[0][run] + alevel - 1;
613  /* store the VLC & sign at once */
614  put_bits(&s->pb, table_vlc[code][1] + 1,
615  (table_vlc[code][0] << 1) + sign);
616  } else {
617  /* escape seems to be pretty rare <5% so I do not optimize it */
618  put_bits(&s->pb, table_vlc[111][1], table_vlc[111][0]);
619  /* escape: only clip in this case */
620  put_bits(&s->pb, 6, run);
621  if (s->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
622  if (alevel < 128) {
623  put_sbits(&s->pb, 8, level);
624  } else {
625  if (level < 0)
626  put_bits(&s->pb, 16, 0x8001 + level + 255);
627  else
628  put_sbits(&s->pb, 16, level);
629  }
630  } else {
631  put_sbits(&s->pb, 12, level);
632  }
633  }
634  last_non_zero = i;
635  }
636  }
637  /* end of block */
638  put_bits(&s->pb, table_vlc[112][1], table_vlc[112][0]);
639 }
640 
641 static av_always_inline void mpeg1_encode_mb_internal(MpegEncContext *s,
642  int16_t block[6][64],
643  int motion_x, int motion_y,
644  int mb_block_count)
645 {
646  int i, cbp;
647  const int mb_x = s->mb_x;
648  const int mb_y = s->mb_y;
649  const int first_mb = mb_x == s->resync_mb_x && mb_y == s->resync_mb_y;
650 
651  /* compute cbp */
652  cbp = 0;
653  for (i = 0; i < mb_block_count; i++)
654  if (s->block_last_index[i] >= 0)
655  cbp |= 1 << (mb_block_count - 1 - i);
656 
657  if (cbp == 0 && !first_mb && s->mv_type == MV_TYPE_16X16 &&
658  (mb_x != s->mb_width - 1 ||
659  (mb_y != s->end_mb_y - 1 && s->codec_id == AV_CODEC_ID_MPEG1VIDEO)) &&
660  ((s->pict_type == AV_PICTURE_TYPE_P && (motion_x | motion_y) == 0) ||
661  (s->pict_type == AV_PICTURE_TYPE_B && s->mv_dir == s->last_mv_dir &&
662  (((s->mv_dir & MV_DIR_FORWARD)
663  ? ((s->mv[0][0][0] - s->last_mv[0][0][0]) |
664  (s->mv[0][0][1] - s->last_mv[0][0][1])) : 0) |
665  ((s->mv_dir & MV_DIR_BACKWARD)
666  ? ((s->mv[1][0][0] - s->last_mv[1][0][0]) |
667  (s->mv[1][0][1] - s->last_mv[1][0][1])) : 0)) == 0))) {
668  s->mb_skip_run++;
669  s->qscale -= s->dquant;
670  s->skip_count++;
671  s->misc_bits++;
672  s->last_bits++;
673  if (s->pict_type == AV_PICTURE_TYPE_P) {
674  s->last_mv[0][0][0] =
675  s->last_mv[0][0][1] =
676  s->last_mv[0][1][0] =
677  s->last_mv[0][1][1] = 0;
678  }
679  } else {
680  if (first_mb) {
681  av_assert0(s->mb_skip_run == 0);
682  encode_mb_skip_run(s, s->mb_x);
683  } else {
684  encode_mb_skip_run(s, s->mb_skip_run);
685  }
686 
687  if (s->pict_type == AV_PICTURE_TYPE_I) {
688  if (s->dquant && cbp) {
689  /* macroblock_type: macroblock_quant = 1 */
690  put_mb_modes(s, 2, 1, 0, 0);
691  put_qscale(s);
692  } else {
693  /* macroblock_type: macroblock_quant = 0 */
694  put_mb_modes(s, 1, 1, 0, 0);
695  s->qscale -= s->dquant;
696  }
697  s->misc_bits += get_bits_diff(s);
698  s->i_count++;
699  } else if (s->mb_intra) {
700  if (s->dquant && cbp) {
701  put_mb_modes(s, 6, 0x01, 0, 0);
702  put_qscale(s);
703  } else {
704  put_mb_modes(s, 5, 0x03, 0, 0);
705  s->qscale -= s->dquant;
706  }
707  s->misc_bits += get_bits_diff(s);
708  s->i_count++;
709  memset(s->last_mv, 0, sizeof(s->last_mv));
710  } else if (s->pict_type == AV_PICTURE_TYPE_P) {
711  if (s->mv_type == MV_TYPE_16X16) {
712  if (cbp != 0) {
713  if ((motion_x | motion_y) == 0) {
714  if (s->dquant) {
715  /* macroblock_pattern & quant */
716  put_mb_modes(s, 5, 1, 0, 0);
717  put_qscale(s);
718  } else {
719  /* macroblock_pattern only */
720  put_mb_modes(s, 2, 1, 0, 0);
721  }
722  s->misc_bits += get_bits_diff(s);
723  } else {
724  if (s->dquant) {
725  put_mb_modes(s, 5, 2, 1, 0); /* motion + cbp */
726  put_qscale(s);
727  } else {
728  put_mb_modes(s, 1, 1, 1, 0); /* motion + cbp */
729  }
730  s->misc_bits += get_bits_diff(s);
731  // RAL: f_code parameter added
732  mpeg1_encode_motion(s,
733  motion_x - s->last_mv[0][0][0],
734  s->f_code);
735  // RAL: f_code parameter added
736  mpeg1_encode_motion(s,
737  motion_y - s->last_mv[0][0][1],
738  s->f_code);
739  s->mv_bits += get_bits_diff(s);
740  }
741  } else {
742  put_bits(&s->pb, 3, 1); /* motion only */
743  if (!s->frame_pred_frame_dct)
744  put_bits(&s->pb, 2, 2); /* motion_type: frame */
745  s->misc_bits += get_bits_diff(s);
746  // RAL: f_code parameter added
747  mpeg1_encode_motion(s,
748  motion_x - s->last_mv[0][0][0],
749  s->f_code);
750  // RAL: f_code parameter added
751  mpeg1_encode_motion(s,
752  motion_y - s->last_mv[0][0][1],
753  s->f_code);
754  s->qscale -= s->dquant;
755  s->mv_bits += get_bits_diff(s);
756  }
757  s->last_mv[0][1][0] = s->last_mv[0][0][0] = motion_x;
758  s->last_mv[0][1][1] = s->last_mv[0][0][1] = motion_y;
759  } else {
760  av_assert2(!s->frame_pred_frame_dct && s->mv_type == MV_TYPE_FIELD);
761 
762  if (cbp) {
763  if (s->dquant) {
764  put_mb_modes(s, 5, 2, 1, 1); /* motion + cbp */
765  put_qscale(s);
766  } else {
767  put_mb_modes(s, 1, 1, 1, 1); /* motion + cbp */
768  }
769  } else {
770  put_bits(&s->pb, 3, 1); /* motion only */
771  put_bits(&s->pb, 2, 1); /* motion_type: field */
772  s->qscale -= s->dquant;
773  }
774  s->misc_bits += get_bits_diff(s);
775  for (i = 0; i < 2; i++) {
776  put_bits(&s->pb, 1, s->field_select[0][i]);
777  mpeg1_encode_motion(s,
778  s->mv[0][i][0] - s->last_mv[0][i][0],
779  s->f_code);
780  mpeg1_encode_motion(s,
781  s->mv[0][i][1] - (s->last_mv[0][i][1] >> 1),
782  s->f_code);
783  s->last_mv[0][i][0] = s->mv[0][i][0];
784  s->last_mv[0][i][1] = 2 * s->mv[0][i][1];
785  }
786  s->mv_bits += get_bits_diff(s);
787  }
788  if (cbp) {
789  if (s->chroma_y_shift) {
790  put_bits(&s->pb,
791  ff_mpeg12_mbPatTable[cbp][1],
792  ff_mpeg12_mbPatTable[cbp][0]);
793  } else {
794  put_bits(&s->pb,
795  ff_mpeg12_mbPatTable[cbp >> 2][1],
796  ff_mpeg12_mbPatTable[cbp >> 2][0]);
797  put_sbits(&s->pb, 2, cbp);
798  }
799  }
800  s->f_count++;
801  } else {
802  if (s->mv_type == MV_TYPE_16X16) {
803  if (cbp) { // With coded bloc pattern
804  if (s->dquant) {
805  if (s->mv_dir == MV_DIR_FORWARD)
806  put_mb_modes(s, 6, 3, 1, 0);
807  else
808  put_mb_modes(s, 8 - s->mv_dir, 2, 1, 0);
809  put_qscale(s);
810  } else {
811  put_mb_modes(s, 5 - s->mv_dir, 3, 1, 0);
812  }
813  } else { // No coded bloc pattern
814  put_bits(&s->pb, 5 - s->mv_dir, 2);
815  if (!s->frame_pred_frame_dct)
816  put_bits(&s->pb, 2, 2); /* motion_type: frame */
817  s->qscale -= s->dquant;
818  }
819  s->misc_bits += get_bits_diff(s);
820  if (s->mv_dir & MV_DIR_FORWARD) {
821  mpeg1_encode_motion(s,
822  s->mv[0][0][0] - s->last_mv[0][0][0],
823  s->f_code);
824  mpeg1_encode_motion(s,
825  s->mv[0][0][1] - s->last_mv[0][0][1],
826  s->f_code);
827  s->last_mv[0][0][0] =
828  s->last_mv[0][1][0] = s->mv[0][0][0];
829  s->last_mv[0][0][1] =
830  s->last_mv[0][1][1] = s->mv[0][0][1];
831  s->f_count++;
832  }
833  if (s->mv_dir & MV_DIR_BACKWARD) {
834  mpeg1_encode_motion(s,
835  s->mv[1][0][0] - s->last_mv[1][0][0],
836  s->b_code);
837  mpeg1_encode_motion(s,
838  s->mv[1][0][1] - s->last_mv[1][0][1],
839  s->b_code);
840  s->last_mv[1][0][0] =
841  s->last_mv[1][1][0] = s->mv[1][0][0];
842  s->last_mv[1][0][1] =
843  s->last_mv[1][1][1] = s->mv[1][0][1];
844  s->b_count++;
845  }
846  } else {
847  av_assert2(s->mv_type == MV_TYPE_FIELD);
848  av_assert2(!s->frame_pred_frame_dct);
849  if (cbp) { // With coded bloc pattern
850  if (s->dquant) {
851  if (s->mv_dir == MV_DIR_FORWARD)
852  put_mb_modes(s, 6, 3, 1, 1);
853  else
854  put_mb_modes(s, 8 - s->mv_dir, 2, 1, 1);
855  put_qscale(s);
856  } else {
857  put_mb_modes(s, 5 - s->mv_dir, 3, 1, 1);
858  }
859  } else { // No coded bloc pattern
860  put_bits(&s->pb, 5 - s->mv_dir, 2);
861  put_bits(&s->pb, 2, 1); /* motion_type: field */
862  s->qscale -= s->dquant;
863  }
864  s->misc_bits += get_bits_diff(s);
865  if (s->mv_dir & MV_DIR_FORWARD) {
866  for (i = 0; i < 2; i++) {
867  put_bits(&s->pb, 1, s->field_select[0][i]);
868  mpeg1_encode_motion(s,
869  s->mv[0][i][0] - s->last_mv[0][i][0],
870  s->f_code);
871  mpeg1_encode_motion(s,
872  s->mv[0][i][1] - (s->last_mv[0][i][1] >> 1),
873  s->f_code);
874  s->last_mv[0][i][0] = s->mv[0][i][0];
875  s->last_mv[0][i][1] = s->mv[0][i][1] * 2;
876  }
877  s->f_count++;
878  }
879  if (s->mv_dir & MV_DIR_BACKWARD) {
880  for (i = 0; i < 2; i++) {
881  put_bits(&s->pb, 1, s->field_select[1][i]);
882  mpeg1_encode_motion(s,
883  s->mv[1][i][0] - s->last_mv[1][i][0],
884  s->b_code);
885  mpeg1_encode_motion(s,
886  s->mv[1][i][1] - (s->last_mv[1][i][1] >> 1),
887  s->b_code);
888  s->last_mv[1][i][0] = s->mv[1][i][0];
889  s->last_mv[1][i][1] = s->mv[1][i][1] * 2;
890  }
891  s->b_count++;
892  }
893  }
894  s->mv_bits += get_bits_diff(s);
895  if (cbp) {
896  if (s->chroma_y_shift) {
897  put_bits(&s->pb,
898  ff_mpeg12_mbPatTable[cbp][1],
899  ff_mpeg12_mbPatTable[cbp][0]);
900  } else {
901  put_bits(&s->pb,
902  ff_mpeg12_mbPatTable[cbp >> 2][1],
903  ff_mpeg12_mbPatTable[cbp >> 2][0]);
904  put_sbits(&s->pb, 2, cbp);
905  }
906  }
907  }
908  for (i = 0; i < mb_block_count; i++)
909  if (cbp & (1 << (mb_block_count - 1 - i)))
910  mpeg1_encode_block(s, block[i], i);
911  s->mb_skip_run = 0;
912  if (s->mb_intra)
913  s->i_tex_bits += get_bits_diff(s);
914  else
915  s->p_tex_bits += get_bits_diff(s);
916  }
917 }
918 
919 void ff_mpeg1_encode_mb(MpegEncContext *s, int16_t block[6][64],
920  int motion_x, int motion_y)
921 {
922  if (s->chroma_format == CHROMA_420)
923  mpeg1_encode_mb_internal(s, block, motion_x, motion_y, 6);
924  else
925  mpeg1_encode_mb_internal(s, block, motion_x, motion_y, 8);
926 }
927 
928 av_cold void ff_mpeg1_encode_init(MpegEncContext *s)
929 {
930  static int done = 0;
931 
932  ff_mpeg12_common_init(s);
933 
934  if (!done) {
935  int f_code;
936  int mv;
937  int i;
938 
939  done = 1;
940  ff_init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
941  ff_init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
942 
943  for (i = 0; i < 64; i++) {
944  mpeg1_max_level[0][i] = ff_rl_mpeg1.max_level[0][i];
945  mpeg1_index_run[0][i] = ff_rl_mpeg1.index_run[0][i];
946  }
947 
948  init_uni_ac_vlc(&ff_rl_mpeg1, uni_mpeg1_ac_vlc_len);
949  if (s->intra_vlc_format)
950  init_uni_ac_vlc(&ff_rl_mpeg2, uni_mpeg2_ac_vlc_len);
951 
952  /* build unified dc encoding tables */
953  for (i = -255; i < 256; i++) {
954  int adiff, index;
955  int bits, code;
956  int diff = i;
957 
958  adiff = FFABS(diff);
959  if (diff < 0)
960  diff--;
961  index = av_log2(2 * adiff);
962 
963  bits = ff_mpeg12_vlc_dc_lum_bits[index] + index;
964  code = (ff_mpeg12_vlc_dc_lum_code[index] << index) +
965  (diff & ((1 << index) - 1));
966  mpeg1_lum_dc_uni[i + 255] = bits + (code << 8);
967 
968  bits = ff_mpeg12_vlc_dc_chroma_bits[index] + index;
969  code = (ff_mpeg12_vlc_dc_chroma_code[index] << index) +
970  (diff & ((1 << index) - 1));
971  mpeg1_chr_dc_uni[i + 255] = bits + (code << 8);
972  }
973 
974  for (f_code = 1; f_code <= MAX_FCODE; f_code++)
975  for (mv = -MAX_MV; mv <= MAX_MV; mv++) {
976  int len;
977 
978  if (mv == 0) {
979  len = ff_mpeg12_mbMotionVectorTable[0][1];
980  } else {
981  int val, bit_size, code;
982 
983  bit_size = f_code - 1;
984 
985  val = mv;
986  if (val < 0)
987  val = -val;
988  val--;
989  code = (val >> bit_size) + 1;
990  if (code < 17)
991  len = ff_mpeg12_mbMotionVectorTable[code][1] +
992  1 + bit_size;
993  else
994  len = ff_mpeg12_mbMotionVectorTable[16][1] +
995  2 + bit_size;
996  }
997 
998  mv_penalty[f_code][mv + MAX_MV] = len;
999  }
1000 
1001 
1002  for (f_code = MAX_FCODE; f_code > 0; f_code--)
1003  for (mv = -(8 << f_code); mv < (8 << f_code); mv++)
1004  fcode_tab[mv + MAX_MV] = f_code;
1005  }
1006  s->me.mv_penalty = mv_penalty;
1007  s->fcode_tab = fcode_tab;
1008  if (s->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1009  s->min_qcoeff = -255;
1010  s->max_qcoeff = 255;
1011  } else {
1012  s->min_qcoeff = -2047;
1013  s->max_qcoeff = 2047;
1014  }
1015  if (s->intra_vlc_format) {
1016  s->intra_ac_vlc_length =
1017  s->intra_ac_vlc_last_length = uni_mpeg2_ac_vlc_len;
1018  } else {
1019  s->intra_ac_vlc_length =
1020  s->intra_ac_vlc_last_length = uni_mpeg1_ac_vlc_len;
1021  }
1022  s->inter_ac_vlc_length =
1023  s->inter_ac_vlc_last_length = uni_mpeg1_ac_vlc_len;
1024 }
1025 
1026 #define OFFSET(x) offsetof(MpegEncContext, x)
1027 #define VE AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM
1028 #define COMMON_OPTS \
1029  { "gop_timecode", "MPEG GOP Timecode in hh:mm:ss[:;.]ff format", \
1030  OFFSET(tc_opt_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, VE },\
1031  { "intra_vlc", "Use MPEG-2 intra VLC table.", \
1032  OFFSET(intra_vlc_format), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VE }, \
1033  { "drop_frame_timecode", "Timecode is in drop frame format.", \
1034  OFFSET(drop_frame_timecode), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VE }, \
1035  { "scan_offset", "Reserve space for SVCD scan offset user data.", \
1036  OFFSET(scan_offset), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VE },
1037 
1038 static const AVOption mpeg1_options[] = {
1039  COMMON_OPTS
1040  FF_MPV_COMMON_OPTS
1041  { NULL },
1042 };
1043 
1044 static const AVOption mpeg2_options[] = {
1045  COMMON_OPTS
1046  { "non_linear_quant", "Use nonlinear quantizer.", OFFSET(q_scale_type), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VE },
1047  { "alternate_scan", "Enable alternate scantable.", OFFSET(alternate_scan), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VE },
1048  FF_MPV_COMMON_OPTS
1049  { NULL },
1050 };
1051 
1052 #define mpeg12_class(x) \
1053 static const AVClass mpeg ## x ## _class = { \
1054  .class_name = "mpeg" # x "video encoder", \
1055  .item_name = av_default_item_name, \
1056  .option = mpeg ## x ## _options, \
1057  .version = LIBAVUTIL_VERSION_INT, \
1058 };
1059 
1060 mpeg12_class(1)
1061 mpeg12_class(2)
1062 
1063 AVCodec ff_mpeg1video_encoder = {
1064  .name = "mpeg1video",
1065  .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
1066  .type = AVMEDIA_TYPE_VIDEO,
1067  .id = AV_CODEC_ID_MPEG1VIDEO,
1068  .priv_data_size = sizeof(MpegEncContext),
1069  .init = encode_init,
1070  .encode2 = ff_MPV_encode_picture,
1071  .close = ff_MPV_encode_end,
1072  .supported_framerates = ff_mpeg12_frame_rate_tab + 1,
1073  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
1074  AV_PIX_FMT_NONE },
1075  .capabilities = CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
1076  .priv_class = &mpeg1_class,
1077 };
1078 
1079 AVCodec ff_mpeg2video_encoder = {
1080  .name = "mpeg2video",
1081  .long_name = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
1082  .type = AVMEDIA_TYPE_VIDEO,
1083  .id = AV_CODEC_ID_MPEG2VIDEO,
1084  .priv_data_size = sizeof(MpegEncContext),
1085  .init = encode_init,
1086  .encode2 = ff_MPV_encode_picture,
1087  .close = ff_MPV_encode_end,
1088  .supported_framerates = ff_mpeg2_frame_rate_tab,
1089  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
1090  AV_PIX_FMT_YUV422P,
1091  AV_PIX_FMT_NONE },
1092  .capabilities = CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
1093  .priv_class = &mpeg2_class,
1094 };
Generated on Sat Jan 25 2014 19:51:51 for FFmpeg by   doxygen 1.8.2