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proresdec_lgpl.c
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1 /*
2  * Apple ProRes compatible decoder
3  *
4  * Copyright (c) 2010-2011 Maxim Poliakovski
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  * 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 "idctdsp.h"
38 #include "internal.h"
39 #include "proresdata.h"
40 #include "proresdsp.h"
41 #include "get_bits.h"
42 
43 typedef struct ProresThreadData {
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 ProresContext {
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  if (avctx->skip_alpha) ctx->alpha_info = 0;
144 
145  switch (ctx->chroma_factor) {
146  case 2:
147  avctx->pix_fmt = ctx->alpha_info ? AV_PIX_FMT_YUVA422P10
148  : AV_PIX_FMT_YUV422P10;
149  break;
150  case 3:
151  avctx->pix_fmt = ctx->alpha_info ? AV_PIX_FMT_YUVA444P10
152  : AV_PIX_FMT_YUV444P10;
153  break;
154  default:
155  av_log(avctx, AV_LOG_ERROR,
156  "unsupported picture format: %d\n", ctx->pic_format);
157  return AVERROR_INVALIDDATA;
158  }
159 
160  if (ctx->scantable_type != ctx->frame_type) {
161  if (!ctx->frame_type)
162  ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable,
163  ff_prores_progressive_scan);
164  else
165  ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable,
166  ff_prores_interlaced_scan);
167  ctx->scantable_type = ctx->frame_type;
168  }
169 
170  if (ctx->frame_type) { /* if interlaced */
171  ctx->frame->interlaced_frame = 1;
172  ctx->frame->top_field_first = ctx->frame_type & 1;
173  } else {
174  ctx->frame->interlaced_frame = 0;
175  }
176 
177  avctx->color_primaries = buf[14];
178  avctx->color_trc = buf[15];
179  avctx->colorspace = buf[16];
180 
181  ctx->qmat_changed = 0;
182  ptr = buf + 20;
183  flags = buf[19];
184  if (flags & 2) {
185  if (ptr - buf > hdr_size - 64) {
186  av_log(avctx, AV_LOG_ERROR, "header data too small\n");
187  return AVERROR_INVALIDDATA;
188  }
189  if (memcmp(ctx->qmat_luma, ptr, 64)) {
190  memcpy(ctx->qmat_luma, ptr, 64);
191  ctx->qmat_changed = 1;
192  }
193  ptr += 64;
194  } else {
195  memset(ctx->qmat_luma, 4, 64);
196  ctx->qmat_changed = 1;
197  }
198 
199  if (flags & 1) {
200  if (ptr - buf > hdr_size - 64) {
201  av_log(avctx, AV_LOG_ERROR, "header data too small\n");
202  return -1;
203  }
204  if (memcmp(ctx->qmat_chroma, ptr, 64)) {
205  memcpy(ctx->qmat_chroma, ptr, 64);
206  ctx->qmat_changed = 1;
207  }
208  } else {
209  memset(ctx->qmat_chroma, 4, 64);
210  ctx->qmat_changed = 1;
211  }
212 
213  return hdr_size;
214 }
215 
216 
217 static int decode_picture_header(ProresContext *ctx, const uint8_t *buf,
218  const int data_size, AVCodecContext *avctx)
219 {
220  int i, hdr_size, pic_data_size, num_slices;
221  int slice_width_factor, slice_height_factor;
222  int remainder, num_x_slices;
223  const uint8_t *data_ptr, *index_ptr;
224 
225  hdr_size = data_size > 0 ? buf[0] >> 3 : 0;
226  if (hdr_size < 8 || hdr_size > data_size) {
227  av_log(avctx, AV_LOG_ERROR, "picture header too small\n");
228  return AVERROR_INVALIDDATA;
229  }
230 
231  pic_data_size = AV_RB32(buf + 1);
232  if (pic_data_size > data_size) {
233  av_log(avctx, AV_LOG_ERROR, "picture data too small\n");
234  return AVERROR_INVALIDDATA;
235  }
236 
237  slice_width_factor = buf[7] >> 4;
238  slice_height_factor = buf[7] & 0xF;
239  if (slice_width_factor > 3 || slice_height_factor) {
240  av_log(avctx, AV_LOG_ERROR,
241  "unsupported slice dimension: %d x %d\n",
242  1 << slice_width_factor, 1 << slice_height_factor);
243  return AVERROR_INVALIDDATA;
244  }
245 
246  ctx->slice_width_factor = slice_width_factor;
247  ctx->slice_height_factor = slice_height_factor;
248 
249  ctx->num_x_mbs = (avctx->width + 15) >> 4;
250  ctx->num_y_mbs = (avctx->height +
251  (1 << (4 + ctx->frame->interlaced_frame)) - 1) >>
252  (4 + ctx->frame->interlaced_frame);
253 
254  remainder = ctx->num_x_mbs & ((1 << slice_width_factor) - 1);
255  num_x_slices = (ctx->num_x_mbs >> slice_width_factor) + (remainder & 1) +
256  ((remainder >> 1) & 1) + ((remainder >> 2) & 1);
257 
258  num_slices = num_x_slices * ctx->num_y_mbs;
259  if (num_slices != AV_RB16(buf + 5)) {
260  av_log(avctx, AV_LOG_ERROR, "invalid number of slices\n");
261  return AVERROR_INVALIDDATA;
262  }
263 
264  if (ctx->total_slices != num_slices) {
265  av_freep(&ctx->slice_data);
266  ctx->slice_data = av_malloc_array(num_slices + 1, sizeof(ctx->slice_data[0]));
267  if (!ctx->slice_data)
268  return AVERROR(ENOMEM);
269  ctx->total_slices = num_slices;
270  }
271 
272  if (hdr_size + num_slices * 2 > data_size) {
273  av_log(avctx, AV_LOG_ERROR, "slice table too small\n");
274  return AVERROR_INVALIDDATA;
275  }
276 
277  /* parse slice table allowing quick access to the slice data */
278  index_ptr = buf + hdr_size;
279  data_ptr = index_ptr + num_slices * 2;
280 
281  for (i = 0; i < num_slices; i++) {
282  ctx->slice_data[i].index = data_ptr;
283  ctx->slice_data[i].prev_slice_sf = 0;
284  data_ptr += AV_RB16(index_ptr + i * 2);
285  }
286  ctx->slice_data[i].index = data_ptr;
287  ctx->slice_data[i].prev_slice_sf = 0;
288 
289  if (data_ptr > buf + data_size) {
290  av_log(avctx, AV_LOG_ERROR, "out of slice data\n");
291  return -1;
292  }
293 
294  return pic_data_size;
295 }
296 
297 
298 /**
299  * Read an unsigned rice/exp golomb codeword.
300  */
301 static inline int decode_vlc_codeword(GetBitContext *gb, unsigned codebook)
302 {
303  unsigned int rice_order, exp_order, switch_bits;
304  unsigned int buf, code;
305  int log, prefix_len, len;
306 
307  OPEN_READER(re, gb);
308  UPDATE_CACHE(re, gb);
309  buf = GET_CACHE(re, gb);
310 
311  /* number of prefix bits to switch between Rice and expGolomb */
312  switch_bits = (codebook & 3) + 1;
313  rice_order = codebook >> 5; /* rice code order */
314  exp_order = (codebook >> 2) & 7; /* exp golomb code order */
315 
316  log = 31 - av_log2(buf); /* count prefix bits (zeroes) */
317 
318  if (log < switch_bits) { /* ok, we got a rice code */
319  if (!rice_order) {
320  /* shortcut for faster decoding of rice codes without remainder */
321  code = log;
322  LAST_SKIP_BITS(re, gb, log + 1);
323  } else {
324  prefix_len = log + 1;
325  code = (log << rice_order) + NEG_USR32(buf << prefix_len, rice_order);
326  LAST_SKIP_BITS(re, gb, prefix_len + rice_order);
327  }
328  } else { /* otherwise we got a exp golomb code */
329  len = (log << 1) - switch_bits + exp_order + 1;
330  code = NEG_USR32(buf, len) - (1 << exp_order) + (switch_bits << rice_order);
331  LAST_SKIP_BITS(re, gb, len);
332  }
333 
334  CLOSE_READER(re, gb);
335 
336  return code;
337 }
338 
339 #define LSB2SIGN(x) (-((x) & 1))
340 #define TOSIGNED(x) (((x) >> 1) ^ LSB2SIGN(x))
341 
342 /**
343  * Decode DC coefficients for all blocks in a slice.
344  */
345 static inline void decode_dc_coeffs(GetBitContext *gb, int16_t *out,
346  int nblocks)
347 {
348  int16_t prev_dc;
349  int i, sign;
350  int16_t delta;
351  unsigned int code;
352 
353  code = decode_vlc_codeword(gb, FIRST_DC_CB);
354  out[0] = prev_dc = TOSIGNED(code);
355 
356  out += 64; /* move to the DC coeff of the next block */
357  delta = 3;
358 
359  for (i = 1; i < nblocks; i++, out += 64) {
360  code = decode_vlc_codeword(gb, ff_prores_dc_codebook[FFMIN(FFABS(delta), 3)]);
361 
362  sign = -(((delta >> 15) & 1) ^ (code & 1));
363  delta = (((code + 1) >> 1) ^ sign) - sign;
364  prev_dc += delta;
365  out[0] = prev_dc;
366  }
367 }
368 
369 #define MAX_PADDING 16
370 
371 /**
372  * Decode AC coefficients for all blocks in a slice.
373  */
374 static inline int decode_ac_coeffs(GetBitContext *gb, int16_t *out,
375  int blocks_per_slice,
376  int plane_size_factor,
377  const uint8_t *scan)
378 {
379  int pos, block_mask, run, level, sign, run_cb_index, lev_cb_index;
380  int max_coeffs, bits_left;
381 
382  /* set initial prediction values */
383  run = 4;
384  level = 2;
385 
386  max_coeffs = blocks_per_slice << 6;
387  block_mask = blocks_per_slice - 1;
388 
389  for (pos = blocks_per_slice - 1; pos < max_coeffs;) {
390  run_cb_index = ff_prores_run_to_cb_index[FFMIN(run, 15)];
391  lev_cb_index = ff_prores_lev_to_cb_index[FFMIN(level, 9)];
392 
393  bits_left = get_bits_left(gb);
394  if (bits_left <= 0 || (bits_left <= MAX_PADDING && !show_bits(gb, bits_left)))
395  return 0;
396 
397  run = decode_vlc_codeword(gb, ff_prores_ac_codebook[run_cb_index]);
398  if (run < 0)
399  return AVERROR_INVALIDDATA;
400 
401  bits_left = get_bits_left(gb);
402  if (bits_left <= 0 || (bits_left <= MAX_PADDING && !show_bits(gb, bits_left)))
403  return AVERROR_INVALIDDATA;
404 
405  level = decode_vlc_codeword(gb, ff_prores_ac_codebook[lev_cb_index]) + 1;
406  if (level < 0)
407  return AVERROR_INVALIDDATA;
408 
409  pos += run + 1;
410  if (pos >= max_coeffs)
411  break;
412 
413  sign = get_sbits(gb, 1);
414  out[((pos & block_mask) << 6) + scan[pos >> plane_size_factor]] =
415  (level ^ sign) - sign;
416  }
417 
418  return 0;
419 }
420 
421 
422 /**
423  * Decode a slice plane (luma or chroma).
424  */
425 static int decode_slice_plane(ProresContext *ctx, ProresThreadData *td,
426  const uint8_t *buf,
427  int data_size, uint16_t *out_ptr,
428  int linesize, int mbs_per_slice,
429  int blocks_per_mb, int plane_size_factor,
430  const int16_t *qmat, int is_chroma)
431 {
432  GetBitContext gb;
433  int16_t *block_ptr;
434  int mb_num, blocks_per_slice, ret;
435 
436  blocks_per_slice = mbs_per_slice * blocks_per_mb;
437 
438  memset(td->blocks, 0, 8 * 4 * 64 * sizeof(*td->blocks));
439 
440  init_get_bits(&gb, buf, data_size << 3);
441 
442  decode_dc_coeffs(&gb, td->blocks, blocks_per_slice);
443 
444  ret = decode_ac_coeffs(&gb, td->blocks, blocks_per_slice,
445  plane_size_factor, ctx->scantable.permutated);
446  if (ret < 0)
447  return ret;
448 
449  /* inverse quantization, inverse transform and output */
450  block_ptr = td->blocks;
451 
452  if (!is_chroma) {
453  for (mb_num = 0; mb_num < mbs_per_slice; mb_num++, out_ptr += blocks_per_mb * 4) {
454  ctx->dsp.idct_put(out_ptr, linesize, block_ptr, qmat);
455  block_ptr += 64;
456  if (blocks_per_mb > 2) {
457  ctx->dsp.idct_put(out_ptr + 8, linesize, block_ptr, qmat);
458  block_ptr += 64;
459  }
460  ctx->dsp.idct_put(out_ptr + linesize * 4, linesize, block_ptr, qmat);
461  block_ptr += 64;
462  if (blocks_per_mb > 2) {
463  ctx->dsp.idct_put(out_ptr + linesize * 4 + 8, linesize, block_ptr, qmat);
464  block_ptr += 64;
465  }
466  }
467  } else {
468  for (mb_num = 0; mb_num < mbs_per_slice; mb_num++, out_ptr += blocks_per_mb * 4) {
469  ctx->dsp.idct_put(out_ptr, linesize, block_ptr, qmat);
470  block_ptr += 64;
471  ctx->dsp.idct_put(out_ptr + linesize * 4, linesize, block_ptr, qmat);
472  block_ptr += 64;
473  if (blocks_per_mb > 2) {
474  ctx->dsp.idct_put(out_ptr + 8, linesize, block_ptr, qmat);
475  block_ptr += 64;
476  ctx->dsp.idct_put(out_ptr + linesize * 4 + 8, linesize, block_ptr, qmat);
477  block_ptr += 64;
478  }
479  }
480  }
481  return 0;
482 }
483 
484 
485 static void unpack_alpha(GetBitContext *gb, uint16_t *dst, int num_coeffs,
486  const int num_bits)
487 {
488  const int mask = (1 << num_bits) - 1;
489  int i, idx, val, alpha_val;
490 
491  idx = 0;
492  alpha_val = mask;
493  do {
494  do {
495  if (get_bits1(gb))
496  val = get_bits(gb, num_bits);
497  else {
498  int sign;
499  val = get_bits(gb, num_bits == 16 ? 7 : 4);
500  sign = val & 1;
501  val = (val + 2) >> 1;
502  if (sign)
503  val = -val;
504  }
505  alpha_val = (alpha_val + val) & mask;
506  if (num_bits == 16)
507  dst[idx++] = alpha_val >> 6;
508  else
509  dst[idx++] = (alpha_val << 2) | (alpha_val >> 6);
510  if (idx >= num_coeffs) {
511  break;
512  }
513  } while (get_bits1(gb));
514  val = get_bits(gb, 4);
515  if (!val)
516  val = get_bits(gb, 11);
517  if (idx + val > num_coeffs)
518  val = num_coeffs - idx;
519  if (num_bits == 16)
520  for (i = 0; i < val; i++)
521  dst[idx++] = alpha_val >> 6;
522  else
523  for (i = 0; i < val; i++)
524  dst[idx++] = (alpha_val << 2) | (alpha_val >> 6);
525  } while (idx < num_coeffs);
526 }
527 
528 /**
529  * Decode alpha slice plane.
530  */
531 static void decode_alpha_plane(ProresContext *ctx, ProresThreadData *td,
532  const uint8_t *buf, int data_size,
533  uint16_t *out_ptr, int linesize,
534  int mbs_per_slice)
535 {
536  GetBitContext gb;
537  int i;
538  uint16_t *block_ptr;
539 
540  memset(td->blocks, 0, 8 * 4 * 64 * sizeof(*td->blocks));
541 
542  init_get_bits(&gb, buf, data_size << 3);
543 
544  if (ctx->alpha_info == 2)
545  unpack_alpha(&gb, td->blocks, mbs_per_slice * 4 * 64, 16);
546  else
547  unpack_alpha(&gb, td->blocks, mbs_per_slice * 4 * 64, 8);
548 
549  block_ptr = td->blocks;
550 
551  for (i = 0; i < 16; i++) {
552  memcpy(out_ptr, block_ptr, 16 * mbs_per_slice * sizeof(*out_ptr));
553  out_ptr += linesize >> 1;
554  block_ptr += 16 * mbs_per_slice;
555  }
556 }
557 
558 static int decode_slice(AVCodecContext *avctx, void *tdata)
559 {
560  ProresThreadData *td = tdata;
561  ProresContext *ctx = avctx->priv_data;
562  int mb_x_pos = td->x_pos;
563  int mb_y_pos = td->y_pos;
564  int pic_num = ctx->pic_num;
565  int slice_num = td->slice_num;
566  int mbs_per_slice = td->slice_width;
567  const uint8_t *buf;
568  uint8_t *y_data, *u_data, *v_data, *a_data;
569  AVFrame *pic = ctx->frame;
570  int i, sf, slice_width_factor;
571  int slice_data_size, hdr_size;
572  int y_data_size, u_data_size, v_data_size, a_data_size;
573  int y_linesize, u_linesize, v_linesize, a_linesize;
574  int coff[4];
575  int ret;
576 
577  buf = ctx->slice_data[slice_num].index;
578  slice_data_size = ctx->slice_data[slice_num + 1].index - buf;
579 
580  slice_width_factor = av_log2(mbs_per_slice);
581 
582  y_data = pic->data[0];
583  u_data = pic->data[1];
584  v_data = pic->data[2];
585  a_data = pic->data[3];
586  y_linesize = pic->linesize[0];
587  u_linesize = pic->linesize[1];
588  v_linesize = pic->linesize[2];
589  a_linesize = pic->linesize[3];
590 
591  if (pic->interlaced_frame) {
592  if (!(pic_num ^ pic->top_field_first)) {
593  y_data += y_linesize;
594  u_data += u_linesize;
595  v_data += v_linesize;
596  if (a_data)
597  a_data += a_linesize;
598  }
599  y_linesize <<= 1;
600  u_linesize <<= 1;
601  v_linesize <<= 1;
602  a_linesize <<= 1;
603  }
604  y_data += (mb_y_pos << 4) * y_linesize + (mb_x_pos << 5);
605  u_data += (mb_y_pos << 4) * u_linesize + (mb_x_pos << ctx->mb_chroma_factor);
606  v_data += (mb_y_pos << 4) * v_linesize + (mb_x_pos << ctx->mb_chroma_factor);
607  if (a_data)
608  a_data += (mb_y_pos << 4) * a_linesize + (mb_x_pos << 5);
609 
610  if (slice_data_size < 6) {
611  av_log(avctx, AV_LOG_ERROR, "slice data too small\n");
612  return AVERROR_INVALIDDATA;
613  }
614 
615  /* parse slice header */
616  hdr_size = buf[0] >> 3;
617  coff[0] = hdr_size;
618  y_data_size = AV_RB16(buf + 2);
619  coff[1] = coff[0] + y_data_size;
620  u_data_size = AV_RB16(buf + 4);
621  coff[2] = coff[1] + u_data_size;
622  v_data_size = hdr_size > 7 ? AV_RB16(buf + 6) : slice_data_size - coff[2];
623  coff[3] = coff[2] + v_data_size;
624  a_data_size = ctx->alpha_info ? slice_data_size - coff[3] : 0;
625 
626  /* if V or alpha component size is negative that means that previous
627  component sizes are too large */
628  if (v_data_size < 0 || a_data_size < 0 || hdr_size < 6) {
629  av_log(avctx, AV_LOG_ERROR, "invalid data size\n");
630  return AVERROR_INVALIDDATA;
631  }
632 
633  sf = av_clip(buf[1], 1, 224);
634  sf = sf > 128 ? (sf - 96) << 2 : sf;
635 
636  /* scale quantization matrixes according with slice's scale factor */
637  /* TODO: this can be SIMD-optimized a lot */
638  if (ctx->qmat_changed || sf != td->prev_slice_sf) {
639  td->prev_slice_sf = sf;
640  for (i = 0; i < 64; i++) {
641  td->qmat_luma_scaled[ctx->dsp.idct_permutation[i]] = ctx->qmat_luma[i] * sf;
642  td->qmat_chroma_scaled[ctx->dsp.idct_permutation[i]] = ctx->qmat_chroma[i] * sf;
643  }
644  }
645 
646  /* decode luma plane */
647  ret = decode_slice_plane(ctx, td, buf + coff[0], y_data_size,
648  (uint16_t*) y_data, y_linesize,
649  mbs_per_slice, 4, slice_width_factor + 2,
650  td->qmat_luma_scaled, 0);
651 
652  if (ret < 0)
653  return ret;
654 
655  /* decode U chroma plane */
656  ret = decode_slice_plane(ctx, td, buf + coff[1], u_data_size,
657  (uint16_t*) u_data, u_linesize,
658  mbs_per_slice, ctx->num_chroma_blocks,
659  slice_width_factor + ctx->chroma_factor - 1,
660  td->qmat_chroma_scaled, 1);
661  if (ret < 0)
662  return ret;
663 
664  /* decode V chroma plane */
665  ret = decode_slice_plane(ctx, td, buf + coff[2], v_data_size,
666  (uint16_t*) v_data, v_linesize,
667  mbs_per_slice, ctx->num_chroma_blocks,
668  slice_width_factor + ctx->chroma_factor - 1,
669  td->qmat_chroma_scaled, 1);
670  if (ret < 0)
671  return ret;
672 
673  /* decode alpha plane if available */
674  if (a_data && a_data_size)
675  decode_alpha_plane(ctx, td, buf + coff[3], a_data_size,
676  (uint16_t*) a_data, a_linesize,
677  mbs_per_slice);
678 
679  return 0;
680 }
681 
682 
683 static int decode_picture(ProresContext *ctx, int pic_num,
684  AVCodecContext *avctx)
685 {
686  int slice_num, slice_width, x_pos, y_pos;
687 
688  slice_num = 0;
689 
690  ctx->pic_num = pic_num;
691  for (y_pos = 0; y_pos < ctx->num_y_mbs; y_pos++) {
692  slice_width = 1 << ctx->slice_width_factor;
693 
694  for (x_pos = 0; x_pos < ctx->num_x_mbs && slice_width;
695  x_pos += slice_width) {
696  while (ctx->num_x_mbs - x_pos < slice_width)
697  slice_width >>= 1;
698 
699  ctx->slice_data[slice_num].slice_num = slice_num;
700  ctx->slice_data[slice_num].x_pos = x_pos;
701  ctx->slice_data[slice_num].y_pos = y_pos;
702  ctx->slice_data[slice_num].slice_width = slice_width;
703 
704  slice_num++;
705  }
706  }
707 
708  return avctx->execute(avctx, decode_slice,
709  ctx->slice_data, NULL, slice_num,
710  sizeof(ctx->slice_data[0]));
711 }
712 
713 
714 #define MOVE_DATA_PTR(nbytes) buf += (nbytes); buf_size -= (nbytes)
715 
716 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
717  AVPacket *avpkt)
718 {
719  ProresContext *ctx = avctx->priv_data;
720  const uint8_t *buf = avpkt->data;
721  int buf_size = avpkt->size;
722  int frame_hdr_size, pic_num, pic_data_size;
723 
724  ctx->frame = data;
725  ctx->frame->pict_type = AV_PICTURE_TYPE_I;
726  ctx->frame->key_frame = 1;
727 
728  /* check frame atom container */
729  if (buf_size < 28 || buf_size < AV_RB32(buf) ||
730  AV_RB32(buf + 4) != FRAME_ID) {
731  av_log(avctx, AV_LOG_ERROR, "invalid frame\n");
732  return AVERROR_INVALIDDATA;
733  }
734 
735  MOVE_DATA_PTR(8);
736 
737  frame_hdr_size = decode_frame_header(ctx, buf, buf_size, avctx);
738  if (frame_hdr_size < 0)
739  return AVERROR_INVALIDDATA;
740 
741  MOVE_DATA_PTR(frame_hdr_size);
742 
743  if (ff_get_buffer(avctx, ctx->frame, 0) < 0)
744  return -1;
745 
746  for (pic_num = 0; ctx->frame->interlaced_frame - pic_num + 1; pic_num++) {
747  pic_data_size = decode_picture_header(ctx, buf, buf_size, avctx);
748  if (pic_data_size < 0)
749  return AVERROR_INVALIDDATA;
750 
751  if (decode_picture(ctx, pic_num, avctx))
752  return -1;
753 
754  MOVE_DATA_PTR(pic_data_size);
755  }
756 
757  ctx->frame = NULL;
758  *got_frame = 1;
759 
760  return avpkt->size;
761 }
762 
763 
764 static av_cold int decode_close(AVCodecContext *avctx)
765 {
766  ProresContext *ctx = avctx->priv_data;
767 
768  av_freep(&ctx->slice_data);
769 
770  return 0;
771 }
772 
773 
774 AVCodec ff_prores_lgpl_decoder = {
775  .name = "prores_lgpl",
776  .long_name = NULL_IF_CONFIG_SMALL("Apple ProRes (iCodec Pro)"),
777  .type = AVMEDIA_TYPE_VIDEO,
778  .id = AV_CODEC_ID_PRORES,
779  .priv_data_size = sizeof(ProresContext),
780  .init = decode_init,
781  .close = decode_close,
782  .decode = decode_frame,
783  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_SLICE_THREADS,
784 };
Generated on Sun Mar 8 2015 02:34:58 for FFmpeg by   doxygen 1.8.2