FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
proresdec_lgpl.c
Go to the documentation of this file.
1 /*
2  * Apple ProRes compatible decoder
3  *
4  * Copyright (c) 2010-2011 Maxim Poliakovski
5  *
6  * This file is part of Libav.
7  *
8  * Libav 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  * Libav 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 Libav; 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  * This is a decoder for Apple ProRes 422 SD/HQ/LT/Proxy and ProRes 4444.
26  * It is used for storing and editing high definition video data in Apple's Final Cut Pro.
27  *
28  * @see http://wiki.multimedia.cx/index.php?title=Apple_ProRes
29  */
30 
31 #define LONG_BITSTREAM_READER // some ProRes vlc codes require up to 28 bits to be read at once
32 
33 #include <stdint.h>
34 
35 #include "libavutil/intmath.h"
36 #include "avcodec.h"
37 #include "dsputil.h"
38 #include "internal.h"
39 #include "proresdata.h"
40 #include "proresdsp.h"
41 #include "get_bits.h"
42 
43 typedef struct {
44  const uint8_t *index; ///< pointers to the data of this slice
45  int slice_num;
46  int x_pos, y_pos;
47  int slice_width;
48  int prev_slice_sf; ///< scalefactor of the previous decoded slice
49  DECLARE_ALIGNED(16, int16_t, blocks)[8 * 4 * 64];
50  DECLARE_ALIGNED(16, int16_t, qmat_luma_scaled)[64];
51  DECLARE_ALIGNED(16, int16_t, qmat_chroma_scaled)[64];
52 } ProresThreadData;
53 
54 typedef struct {
55  ProresDSPContext dsp;
56  AVFrame *frame;
57  ScanTable scantable;
58  int scantable_type; ///< -1 = uninitialized, 0 = progressive, 1/2 = interlaced
59 
60  int frame_type; ///< 0 = progressive, 1 = top-field first, 2 = bottom-field first
61  int pic_format; ///< 2 = 422, 3 = 444
62  uint8_t qmat_luma[64]; ///< dequantization matrix for luma
63  uint8_t qmat_chroma[64]; ///< dequantization matrix for chroma
64  int qmat_changed; ///< 1 - global quantization matrices changed
65  int total_slices; ///< total number of slices in a picture
66  ProresThreadData *slice_data;
67  int pic_num;
68  int chroma_factor;
69  int mb_chroma_factor;
70  int num_chroma_blocks; ///< number of chrominance blocks in a macroblock
71  int num_x_slices;
72  int num_y_slices;
73  int slice_width_factor;
74  int slice_height_factor;
75  int num_x_mbs;
76  int num_y_mbs;
77  int alpha_info;
78 } ProresContext;
79 
80 
81 static av_cold int decode_init(AVCodecContext *avctx)
82 {
83  ProresContext *ctx = avctx->priv_data;
84 
85  ctx->total_slices = 0;
86  ctx->slice_data = NULL;
87 
88  avctx->bits_per_raw_sample = PRORES_BITS_PER_SAMPLE;
89  ff_proresdsp_init(&ctx->dsp, avctx);
90 
91  ctx->scantable_type = -1; // set scantable type to uninitialized
92  memset(ctx->qmat_luma, 4, 64);
93  memset(ctx->qmat_chroma, 4, 64);
94 
95  return 0;
96 }
97 
98 
99 static int decode_frame_header(ProresContext *ctx, const uint8_t *buf,
100  const int data_size, AVCodecContext *avctx)
101 {
102  int hdr_size, version, width, height, flags;
103  const uint8_t *ptr;
104 
105  hdr_size = AV_RB16(buf);
106  if (hdr_size > data_size) {
107  av_log(avctx, AV_LOG_ERROR, "frame data too small\n");
108  return AVERROR_INVALIDDATA;
109  }
110 
111  version = AV_RB16(buf + 2);
112  if (version >= 2) {
113  av_log(avctx, AV_LOG_ERROR,
114  "unsupported header version: %d\n", version);
115  return AVERROR_INVALIDDATA;
116  }
117 
118  width = AV_RB16(buf + 8);
119  height = AV_RB16(buf + 10);
120  if (width != avctx->width || height != avctx->height) {
121  av_log(avctx, AV_LOG_ERROR,
122  "picture dimension changed: old: %d x %d, new: %d x %d\n",
123  avctx->width, avctx->height, width, height);
124  return AVERROR_INVALIDDATA;
125  }
126 
127  ctx->frame_type = (buf[12] >> 2) & 3;
128  if (ctx->frame_type > 2) {
129  av_log(avctx, AV_LOG_ERROR,
130  "unsupported frame type: %d\n", ctx->frame_type);
131  return AVERROR_INVALIDDATA;
132  }
133 
134  ctx->chroma_factor = (buf[12] >> 6) & 3;
135  ctx->mb_chroma_factor = ctx->chroma_factor + 2;
136  ctx->num_chroma_blocks = (1 << ctx->chroma_factor) >> 1;
137  ctx->alpha_info = buf[17] & 0xf;
138 
139  if (ctx->alpha_info > 2) {
140  av_log(avctx, AV_LOG_ERROR, "Invalid alpha mode %d\n", ctx->alpha_info);
141  return AVERROR_INVALIDDATA;
142  }
143 
144  switch (ctx->chroma_factor) {
145  case 2:
146  avctx->pix_fmt = ctx->alpha_info ? AV_PIX_FMT_YUVA422P10
147  : AV_PIX_FMT_YUV422P10;
148  break;
149  case 3:
150  avctx->pix_fmt = ctx->alpha_info ? AV_PIX_FMT_YUVA444P10
151  : AV_PIX_FMT_YUV444P10;
152  break;
153  default:
154  av_log(avctx, AV_LOG_ERROR,
155  "unsupported picture format: %d\n", ctx->pic_format);
156  return AVERROR_INVALIDDATA;
157  }
158 
159  if (ctx->scantable_type != ctx->frame_type) {
160  if (!ctx->frame_type)
161  ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable,
162  ff_prores_progressive_scan);
163  else
164  ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable,
165  ff_prores_interlaced_scan);
166  ctx->scantable_type = ctx->frame_type;
167  }
168 
169  if (ctx->frame_type) { /* if interlaced */
170  ctx->frame->interlaced_frame = 1;
171  ctx->frame->top_field_first = ctx->frame_type & 1;
172  } else {
173  ctx->frame->interlaced_frame = 0;
174  }
175 
176  avctx->color_primaries = buf[14];
177  avctx->color_trc = buf[15];
178  avctx->colorspace = buf[16];
179 
180  ctx->qmat_changed = 0;
181  ptr = buf + 20;
182  flags = buf[19];
183  if (flags & 2) {
184  if (ptr - buf > hdr_size - 64) {
185  av_log(avctx, AV_LOG_ERROR, "header data too small\n");
186  return AVERROR_INVALIDDATA;
187  }
188  if (memcmp(ctx->qmat_luma, ptr, 64)) {
189  memcpy(ctx->qmat_luma, ptr, 64);
190  ctx->qmat_changed = 1;
191  }
192  ptr += 64;
193  } else {
194  memset(ctx->qmat_luma, 4, 64);
195  ctx->qmat_changed = 1;
196  }
197 
198  if (flags & 1) {
199  if (ptr - buf > hdr_size - 64) {
200  av_log(avctx, AV_LOG_ERROR, "header data too small\n");
201  return -1;
202  }
203  if (memcmp(ctx->qmat_chroma, ptr, 64)) {
204  memcpy(ctx->qmat_chroma, ptr, 64);
205  ctx->qmat_changed = 1;
206  }
207  } else {
208  memset(ctx->qmat_chroma, 4, 64);
209  ctx->qmat_changed = 1;
210  }
211 
212  return hdr_size;
213 }
214 
215 
216 static int decode_picture_header(ProresContext *ctx, const uint8_t *buf,
217  const int data_size, AVCodecContext *avctx)
218 {
219  int i, hdr_size, pic_data_size, num_slices;
220  int slice_width_factor, slice_height_factor;
221  int remainder, num_x_slices;
222  const uint8_t *data_ptr, *index_ptr;
223 
224  hdr_size = data_size > 0 ? buf[0] >> 3 : 0;
225  if (hdr_size < 8 || hdr_size > data_size) {
226  av_log(avctx, AV_LOG_ERROR, "picture header too small\n");
227  return AVERROR_INVALIDDATA;
228  }
229 
230  pic_data_size = AV_RB32(buf + 1);
231  if (pic_data_size > data_size) {
232  av_log(avctx, AV_LOG_ERROR, "picture data too small\n");
233  return AVERROR_INVALIDDATA;
234  }
235 
236  slice_width_factor = buf[7] >> 4;
237  slice_height_factor = buf[7] & 0xF;
238  if (slice_width_factor > 3 || slice_height_factor) {
239  av_log(avctx, AV_LOG_ERROR,
240  "unsupported slice dimension: %d x %d\n",
241  1 << slice_width_factor, 1 << slice_height_factor);
242  return AVERROR_INVALIDDATA;
243  }
244 
245  ctx->slice_width_factor = slice_width_factor;
246  ctx->slice_height_factor = slice_height_factor;
247 
248  ctx->num_x_mbs = (avctx->width + 15) >> 4;
249  ctx->num_y_mbs = (avctx->height +
250  (1 << (4 + ctx->frame->interlaced_frame)) - 1) >>
251  (4 + ctx->frame->interlaced_frame);
252 
253  remainder = ctx->num_x_mbs & ((1 << slice_width_factor) - 1);
254  num_x_slices = (ctx->num_x_mbs >> slice_width_factor) + (remainder & 1) +
255  ((remainder >> 1) & 1) + ((remainder >> 2) & 1);
256 
257  num_slices = num_x_slices * ctx->num_y_mbs;
258  if (num_slices != AV_RB16(buf + 5)) {
259  av_log(avctx, AV_LOG_ERROR, "invalid number of slices\n");
260  return AVERROR_INVALIDDATA;
261  }
262 
263  if (ctx->total_slices != num_slices) {
264  av_freep(&ctx->slice_data);
265  ctx->slice_data = av_malloc((num_slices + 1) * sizeof(ctx->slice_data[0]));
266  if (!ctx->slice_data)
267  return AVERROR(ENOMEM);
268  ctx->total_slices = num_slices;
269  }
270 
271  if (hdr_size + num_slices * 2 > data_size) {
272  av_log(avctx, AV_LOG_ERROR, "slice table too small\n");
273  return AVERROR_INVALIDDATA;
274  }
275 
276  /* parse slice table allowing quick access to the slice data */
277  index_ptr = buf + hdr_size;
278  data_ptr = index_ptr + num_slices * 2;
279 
280  for (i = 0; i < num_slices; i++) {
281  ctx->slice_data[i].index = data_ptr;
282  ctx->slice_data[i].prev_slice_sf = 0;
283  data_ptr += AV_RB16(index_ptr + i * 2);
284  }
285  ctx->slice_data[i].index = data_ptr;
286  ctx->slice_data[i].prev_slice_sf = 0;
287 
288  if (data_ptr > buf + data_size) {
289  av_log(avctx, AV_LOG_ERROR, "out of slice data\n");
290  return -1;
291  }
292 
293  return pic_data_size;
294 }
295 
296 
297 /**
298  * Read an unsigned rice/exp golomb codeword.
299  */
300 static inline int decode_vlc_codeword(GetBitContext *gb, unsigned codebook)
301 {
302  unsigned int rice_order, exp_order, switch_bits;
303  unsigned int buf, code;
304  int log, prefix_len, len;
305 
306  OPEN_READER(re, gb);
307  UPDATE_CACHE(re, gb);
308  buf = GET_CACHE(re, gb);
309 
310  /* number of prefix bits to switch between Rice and expGolomb */
311  switch_bits = (codebook & 3) + 1;
312  rice_order = codebook >> 5; /* rice code order */
313  exp_order = (codebook >> 2) & 7; /* exp golomb code order */
314 
315  log = 31 - av_log2(buf); /* count prefix bits (zeroes) */
316 
317  if (log < switch_bits) { /* ok, we got a rice code */
318  if (!rice_order) {
319  /* shortcut for faster decoding of rice codes without remainder */
320  code = log;
321  LAST_SKIP_BITS(re, gb, log + 1);
322  } else {
323  prefix_len = log + 1;
324  code = (log << rice_order) + NEG_USR32(buf << prefix_len, rice_order);
325  LAST_SKIP_BITS(re, gb, prefix_len + rice_order);
326  }
327  } else { /* otherwise we got a exp golomb code */
328  len = (log << 1) - switch_bits + exp_order + 1;
329  code = NEG_USR32(buf, len) - (1 << exp_order) + (switch_bits << rice_order);
330  LAST_SKIP_BITS(re, gb, len);
331  }
332 
333  CLOSE_READER(re, gb);
334 
335  return code;
336 }
337 
338 #define LSB2SIGN(x) (-((x) & 1))
339 #define TOSIGNED(x) (((x) >> 1) ^ LSB2SIGN(x))
340 
341 /**
342  * Decode DC coefficients for all blocks in a slice.
343  */
344 static inline void decode_dc_coeffs(GetBitContext *gb, int16_t *out,
345  int nblocks)
346 {
347  int16_t prev_dc;
348  int i, sign;
349  int16_t delta;
350  unsigned int code;
351 
352  code = decode_vlc_codeword(gb, FIRST_DC_CB);
353  out[0] = prev_dc = TOSIGNED(code);
354 
355  out += 64; /* move to the DC coeff of the next block */
356  delta = 3;
357 
358  for (i = 1; i < nblocks; i++, out += 64) {
359  code = decode_vlc_codeword(gb, ff_prores_dc_codebook[FFMIN(FFABS(delta), 3)]);
360 
361  sign = -(((delta >> 15) & 1) ^ (code & 1));
362  delta = (((code + 1) >> 1) ^ sign) - sign;
363  prev_dc += delta;
364  out[0] = prev_dc;
365  }
366 }
367 
368 
369 /**
370  * Decode AC coefficients for all blocks in a slice.
371  */
372 static inline void decode_ac_coeffs(GetBitContext *gb, int16_t *out,
373  int blocks_per_slice,
374  int plane_size_factor,
375  const uint8_t *scan)
376 {
377  int pos, block_mask, run, level, sign, run_cb_index, lev_cb_index;
378  int max_coeffs, bits_left;
379 
380  /* set initial prediction values */
381  run = 4;
382  level = 2;
383 
384  max_coeffs = blocks_per_slice << 6;
385  block_mask = blocks_per_slice - 1;
386 
387  for (pos = blocks_per_slice - 1; pos < max_coeffs;) {
388  run_cb_index = ff_prores_run_to_cb_index[FFMIN(run, 15)];
389  lev_cb_index = ff_prores_lev_to_cb_index[FFMIN(level, 9)];
390 
391  bits_left = get_bits_left(gb);
392  if (bits_left <= 0 || (bits_left <= 8 && !show_bits(gb, bits_left)))
393  return;
394 
395  run = decode_vlc_codeword(gb, ff_prores_ac_codebook[run_cb_index]);
396 
397  bits_left = get_bits_left(gb);
398  if (bits_left <= 0 || (bits_left <= 8 && !show_bits(gb, bits_left)))
399  return;
400 
401  level = decode_vlc_codeword(gb, ff_prores_ac_codebook[lev_cb_index]) + 1;
402 
403  pos += run + 1;
404  if (pos >= max_coeffs)
405  break;
406 
407  sign = get_sbits(gb, 1);
408  out[((pos & block_mask) << 6) + scan[pos >> plane_size_factor]] =
409  (level ^ sign) - sign;
410  }
411 }
412 
413 
414 /**
415  * Decode a slice plane (luma or chroma).
416  */
417 static void decode_slice_plane(ProresContext *ctx, ProresThreadData *td,
418  const uint8_t *buf,
419  int data_size, uint16_t *out_ptr,
420  int linesize, int mbs_per_slice,
421  int blocks_per_mb, int plane_size_factor,
422  const int16_t *qmat, int is_chroma)
423 {
424  GetBitContext gb;
425  int16_t *block_ptr;
426  int mb_num, blocks_per_slice;
427 
428  blocks_per_slice = mbs_per_slice * blocks_per_mb;
429 
430  memset(td->blocks, 0, 8 * 4 * 64 * sizeof(*td->blocks));
431 
432  init_get_bits(&gb, buf, data_size << 3);
433 
434  decode_dc_coeffs(&gb, td->blocks, blocks_per_slice);
435 
436  decode_ac_coeffs(&gb, td->blocks, blocks_per_slice,
437  plane_size_factor, ctx->scantable.permutated);
438 
439  /* inverse quantization, inverse transform and output */
440  block_ptr = td->blocks;
441 
442  if (!is_chroma) {
443  for (mb_num = 0; mb_num < mbs_per_slice; mb_num++, out_ptr += blocks_per_mb * 4) {
444  ctx->dsp.idct_put(out_ptr, linesize, block_ptr, qmat);
445  block_ptr += 64;
446  if (blocks_per_mb > 2) {
447  ctx->dsp.idct_put(out_ptr + 8, linesize, block_ptr, qmat);
448  block_ptr += 64;
449  }
450  ctx->dsp.idct_put(out_ptr + linesize * 4, linesize, block_ptr, qmat);
451  block_ptr += 64;
452  if (blocks_per_mb > 2) {
453  ctx->dsp.idct_put(out_ptr + linesize * 4 + 8, linesize, block_ptr, qmat);
454  block_ptr += 64;
455  }
456  }
457  } else {
458  for (mb_num = 0; mb_num < mbs_per_slice; mb_num++, out_ptr += blocks_per_mb * 4) {
459  ctx->dsp.idct_put(out_ptr, linesize, block_ptr, qmat);
460  block_ptr += 64;
461  ctx->dsp.idct_put(out_ptr + linesize * 4, linesize, block_ptr, qmat);
462  block_ptr += 64;
463  if (blocks_per_mb > 2) {
464  ctx->dsp.idct_put(out_ptr + 8, linesize, block_ptr, qmat);
465  block_ptr += 64;
466  ctx->dsp.idct_put(out_ptr + linesize * 4 + 8, linesize, block_ptr, qmat);
467  block_ptr += 64;
468  }
469  }
470  }
471 }
472 
473 
474 static void unpack_alpha(GetBitContext *gb, uint16_t *dst, int num_coeffs,
475  const int num_bits)
476 {
477  const int mask = (1 << num_bits) - 1;
478  int i, idx, val, alpha_val;
479 
480  idx = 0;
481  alpha_val = mask;
482  do {
483  do {
484  if (get_bits1(gb))
485  val = get_bits(gb, num_bits);
486  else {
487  int sign;
488  val = get_bits(gb, num_bits == 16 ? 7 : 4);
489  sign = val & 1;
490  val = (val + 2) >> 1;
491  if (sign)
492  val = -val;
493  }
494  alpha_val = (alpha_val + val) & mask;
495  if (num_bits == 16)
496  dst[idx++] = alpha_val >> 6;
497  else
498  dst[idx++] = (alpha_val << 2) | (alpha_val >> 6);
499  if (idx >= num_coeffs)
500  break;
501  } while (get_bits1(gb));
502  val = get_bits(gb, 4);
503  if (!val)
504  val = get_bits(gb, 11);
505  if (idx + val > num_coeffs)
506  val = num_coeffs - idx;
507  if (num_bits == 16)
508  for (i = 0; i < val; i++)
509  dst[idx++] = alpha_val >> 6;
510  else
511  for (i = 0; i < val; i++)
512  dst[idx++] = (alpha_val << 2) | (alpha_val >> 6);
513  } while (idx < num_coeffs);
514 }
515 
516 /**
517  * Decode alpha slice plane.
518  */
519 static void decode_alpha_plane(ProresContext *ctx, ProresThreadData *td,
520  const uint8_t *buf, int data_size,
521  uint16_t *out_ptr, int linesize,
522  int mbs_per_slice)
523 {
524  GetBitContext gb;
525  int i;
526  uint16_t *block_ptr;
527 
528  memset(td->blocks, 0, 8 * 4 * 64 * sizeof(*td->blocks));
529 
530  init_get_bits(&gb, buf, data_size << 3);
531 
532  if (ctx->alpha_info == 2)
533  unpack_alpha(&gb, td->blocks, mbs_per_slice * 4 * 64, 16);
534  else
535  unpack_alpha(&gb, td->blocks, mbs_per_slice * 4 * 64, 8);
536 
537  block_ptr = td->blocks;
538 
539  for (i = 0; i < 16; i++) {
540  memcpy(out_ptr, block_ptr, 16 * mbs_per_slice * sizeof(*out_ptr));
541  out_ptr += linesize >> 1;
542  block_ptr += 16 * mbs_per_slice;
543  }
544 }
545 
546 static int decode_slice(AVCodecContext *avctx, void *tdata)
547 {
548  ProresThreadData *td = tdata;
549  ProresContext *ctx = avctx->priv_data;
550  int mb_x_pos = td->x_pos;
551  int mb_y_pos = td->y_pos;
552  int pic_num = ctx->pic_num;
553  int slice_num = td->slice_num;
554  int mbs_per_slice = td->slice_width;
555  const uint8_t *buf;
556  uint8_t *y_data, *u_data, *v_data, *a_data;
557  AVFrame *pic = ctx->frame;
558  int i, sf, slice_width_factor;
559  int slice_data_size, hdr_size;
560  int y_data_size, u_data_size, v_data_size, a_data_size;
561  int y_linesize, u_linesize, v_linesize, a_linesize;
562  int coff[4];
563 
564  buf = ctx->slice_data[slice_num].index;
565  slice_data_size = ctx->slice_data[slice_num + 1].index - buf;
566 
567  slice_width_factor = av_log2(mbs_per_slice);
568 
569  y_data = pic->data[0];
570  u_data = pic->data[1];
571  v_data = pic->data[2];
572  a_data = pic->data[3];
573  y_linesize = pic->linesize[0];
574  u_linesize = pic->linesize[1];
575  v_linesize = pic->linesize[2];
576  a_linesize = pic->linesize[3];
577 
578  if (pic->interlaced_frame) {
579  if (!(pic_num ^ pic->top_field_first)) {
580  y_data += y_linesize;
581  u_data += u_linesize;
582  v_data += v_linesize;
583  if (a_data)
584  a_data += a_linesize;
585  }
586  y_linesize <<= 1;
587  u_linesize <<= 1;
588  v_linesize <<= 1;
589  a_linesize <<= 1;
590  }
591  y_data += (mb_y_pos << 4) * y_linesize + (mb_x_pos << 5);
592  u_data += (mb_y_pos << 4) * u_linesize + (mb_x_pos << ctx->mb_chroma_factor);
593  v_data += (mb_y_pos << 4) * v_linesize + (mb_x_pos << ctx->mb_chroma_factor);
594  if (a_data)
595  a_data += (mb_y_pos << 4) * a_linesize + (mb_x_pos << 5);
596 
597  if (slice_data_size < 6) {
598  av_log(avctx, AV_LOG_ERROR, "slice data too small\n");
599  return AVERROR_INVALIDDATA;
600  }
601 
602  /* parse slice header */
603  hdr_size = buf[0] >> 3;
604  coff[0] = hdr_size;
605  y_data_size = AV_RB16(buf + 2);
606  coff[1] = coff[0] + y_data_size;
607  u_data_size = AV_RB16(buf + 4);
608  coff[2] = coff[1] + u_data_size;
609  v_data_size = hdr_size > 7 ? AV_RB16(buf + 6) : slice_data_size - coff[2];
610  coff[3] = coff[2] + v_data_size;
611  a_data_size = slice_data_size - coff[3];
612 
613  /* if V or alpha component size is negative that means that previous
614  component sizes are too large */
615  if (v_data_size < 0 || a_data_size < 0 || hdr_size < 6) {
616  av_log(avctx, AV_LOG_ERROR, "invalid data size\n");
617  return AVERROR_INVALIDDATA;
618  }
619 
620  sf = av_clip(buf[1], 1, 224);
621  sf = sf > 128 ? (sf - 96) << 2 : sf;
622 
623  /* scale quantization matrixes according with slice's scale factor */
624  /* TODO: this can be SIMD-optimized a lot */
625  if (ctx->qmat_changed || sf != td->prev_slice_sf) {
626  td->prev_slice_sf = sf;
627  for (i = 0; i < 64; i++) {
628  td->qmat_luma_scaled[ctx->dsp.idct_permutation[i]] = ctx->qmat_luma[i] * sf;
629  td->qmat_chroma_scaled[ctx->dsp.idct_permutation[i]] = ctx->qmat_chroma[i] * sf;
630  }
631  }
632 
633  /* decode luma plane */
634  decode_slice_plane(ctx, td, buf + coff[0], y_data_size,
635  (uint16_t*) y_data, y_linesize,
636  mbs_per_slice, 4, slice_width_factor + 2,
637  td->qmat_luma_scaled, 0);
638 
639  /* decode U chroma plane */
640  decode_slice_plane(ctx, td, buf + coff[1], u_data_size,
641  (uint16_t*) u_data, u_linesize,
642  mbs_per_slice, ctx->num_chroma_blocks,
643  slice_width_factor + ctx->chroma_factor - 1,
644  td->qmat_chroma_scaled, 1);
645 
646  /* decode V chroma plane */
647  decode_slice_plane(ctx, td, buf + coff[2], v_data_size,
648  (uint16_t*) v_data, v_linesize,
649  mbs_per_slice, ctx->num_chroma_blocks,
650  slice_width_factor + ctx->chroma_factor - 1,
651  td->qmat_chroma_scaled, 1);
652 
653  /* decode alpha plane if available */
654  if (a_data && a_data_size)
655  decode_alpha_plane(ctx, td, buf + coff[3], a_data_size,
656  (uint16_t*) a_data, a_linesize,
657  mbs_per_slice);
658 
659  return 0;
660 }
661 
662 
663 static int decode_picture(ProresContext *ctx, int pic_num,
664  AVCodecContext *avctx)
665 {
666  int slice_num, slice_width, x_pos, y_pos;
667 
668  slice_num = 0;
669 
670  ctx->pic_num = pic_num;
671  for (y_pos = 0; y_pos < ctx->num_y_mbs; y_pos++) {
672  slice_width = 1 << ctx->slice_width_factor;
673 
674  for (x_pos = 0; x_pos < ctx->num_x_mbs && slice_width;
675  x_pos += slice_width) {
676  while (ctx->num_x_mbs - x_pos < slice_width)
677  slice_width >>= 1;
678 
679  ctx->slice_data[slice_num].slice_num = slice_num;
680  ctx->slice_data[slice_num].x_pos = x_pos;
681  ctx->slice_data[slice_num].y_pos = y_pos;
682  ctx->slice_data[slice_num].slice_width = slice_width;
683 
684  slice_num++;
685  }
686  }
687 
688  return avctx->execute(avctx, decode_slice,
689  ctx->slice_data, NULL, slice_num,
690  sizeof(ctx->slice_data[0]));
691 }
692 
693 
694 #define MOVE_DATA_PTR(nbytes) buf += (nbytes); buf_size -= (nbytes)
695 
696 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
697  AVPacket *avpkt)
698 {
699  ProresContext *ctx = avctx->priv_data;
700  const uint8_t *buf = avpkt->data;
701  int buf_size = avpkt->size;
702  int frame_hdr_size, pic_num, pic_data_size;
703 
704  ctx->frame = data;
705  ctx->frame->pict_type = AV_PICTURE_TYPE_I;
706  ctx->frame->key_frame = 1;
707 
708  /* check frame atom container */
709  if (buf_size < 28 || buf_size < AV_RB32(buf) ||
710  AV_RB32(buf + 4) != FRAME_ID) {
711  av_log(avctx, AV_LOG_ERROR, "invalid frame\n");
712  return AVERROR_INVALIDDATA;
713  }
714 
715  MOVE_DATA_PTR(8);
716 
717  frame_hdr_size = decode_frame_header(ctx, buf, buf_size, avctx);
718  if (frame_hdr_size < 0)
719  return AVERROR_INVALIDDATA;
720 
721  MOVE_DATA_PTR(frame_hdr_size);
722 
723  if (ff_get_buffer(avctx, ctx->frame, 0) < 0)
724  return -1;
725 
726  for (pic_num = 0; ctx->frame->interlaced_frame - pic_num + 1; pic_num++) {
727  pic_data_size = decode_picture_header(ctx, buf, buf_size, avctx);
728  if (pic_data_size < 0)
729  return AVERROR_INVALIDDATA;
730 
731  if (decode_picture(ctx, pic_num, avctx))
732  return -1;
733 
734  MOVE_DATA_PTR(pic_data_size);
735  }
736 
737  ctx->frame = NULL;
738  *got_frame = 1;
739 
740  return avpkt->size;
741 }
742 
743 
744 static av_cold int decode_close(AVCodecContext *avctx)
745 {
746  ProresContext *ctx = avctx->priv_data;
747 
748  av_freep(&ctx->slice_data);
749 
750  return 0;
751 }
752 
753 
754 AVCodec ff_prores_lgpl_decoder = {
755  .name = "prores_lgpl",
756  .type = AVMEDIA_TYPE_VIDEO,
757  .id = AV_CODEC_ID_PRORES,
758  .priv_data_size = sizeof(ProresContext),
759  .init = decode_init,
760  .close = decode_close,
761  .decode = decode_frame,
762  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_SLICE_THREADS,
763  .long_name = NULL_IF_CONFIG_SMALL("Apple ProRes (iCodec Pro)")
764 };
Generated on Wed Jul 10 2013 23:48:03 for FFmpeg by   doxygen 1.8.2