utvideodec.c
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1 /*
2  * Ut Video decoder
3  * Copyright (c) 2011 Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
27 #include <stdlib.h>
28 
29 #include "libavutil/intreadwrite.h"
30 #include "avcodec.h"
31 #include "bytestream.h"
32 #include "get_bits.h"
33 #include "dsputil.h"
34 #include "thread.h"
35 #include "utvideo.h"
36 
37 static int build_huff(const uint8_t *src, VLC *vlc, int *fsym)
38 {
39  int i;
40  HuffEntry he[256];
41  int last;
42  uint32_t codes[256];
43  uint8_t bits[256];
44  uint8_t syms[256];
45  uint32_t code;
46 
47  *fsym = -1;
48  for (i = 0; i < 256; i++) {
49  he[i].sym = i;
50  he[i].len = *src++;
51  }
52  qsort(he, 256, sizeof(*he), ff_ut_huff_cmp_len);
53 
54  if (!he[0].len) {
55  *fsym = he[0].sym;
56  return 0;
57  }
58  if (he[0].len > 32)
59  return -1;
60 
61  last = 255;
62  while (he[last].len == 255 && last)
63  last--;
64 
65  code = 1;
66  for (i = last; i >= 0; i--) {
67  codes[i] = code >> (32 - he[i].len);
68  bits[i] = he[i].len;
69  syms[i] = he[i].sym;
70  code += 0x80000000u >> (he[i].len - 1);
71  }
72 
73  return ff_init_vlc_sparse(vlc, FFMIN(he[last].len, 9), last + 1,
74  bits, sizeof(*bits), sizeof(*bits),
75  codes, sizeof(*codes), sizeof(*codes),
76  syms, sizeof(*syms), sizeof(*syms), 0);
77 }
78 
79 static int decode_plane(UtvideoContext *c, int plane_no,
80  uint8_t *dst, int step, int stride,
81  int width, int height,
82  const uint8_t *src, int use_pred)
83 {
84  int i, j, slice, pix;
85  int sstart, send;
86  VLC vlc;
87  GetBitContext gb;
88  int prev, fsym;
89  const int cmask = ~(!plane_no && c->avctx->pix_fmt == AV_PIX_FMT_YUV420P);
90 
91  if (build_huff(src, &vlc, &fsym)) {
92  av_log(c->avctx, AV_LOG_ERROR, "Cannot build Huffman codes\n");
93  return AVERROR_INVALIDDATA;
94  }
95  if (fsym >= 0) { // build_huff reported a symbol to fill slices with
96  send = 0;
97  for (slice = 0; slice < c->slices; slice++) {
98  uint8_t *dest;
99 
100  sstart = send;
101  send = (height * (slice + 1) / c->slices) & cmask;
102  dest = dst + sstart * stride;
103 
104  prev = 0x80;
105  for (j = sstart; j < send; j++) {
106  for (i = 0; i < width * step; i += step) {
107  pix = fsym;
108  if (use_pred) {
109  prev += pix;
110  pix = prev;
111  }
112  dest[i] = pix;
113  }
114  dest += stride;
115  }
116  }
117  return 0;
118  }
119 
120  src += 256;
121 
122  send = 0;
123  for (slice = 0; slice < c->slices; slice++) {
124  uint8_t *dest;
125  int slice_data_start, slice_data_end, slice_size;
126 
127  sstart = send;
128  send = (height * (slice + 1) / c->slices) & cmask;
129  dest = dst + sstart * stride;
130 
131  // slice offset and size validation was done earlier
132  slice_data_start = slice ? AV_RL32(src + slice * 4 - 4) : 0;
133  slice_data_end = AV_RL32(src + slice * 4);
134  slice_size = slice_data_end - slice_data_start;
135 
136  if (!slice_size) {
137  av_log(c->avctx, AV_LOG_ERROR, "Plane has more than one symbol "
138  "yet a slice has a length of zero.\n");
139  goto fail;
140  }
141 
142  memcpy(c->slice_bits, src + slice_data_start + c->slices * 4,
143  slice_size);
144  memset(c->slice_bits + slice_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
145  c->dsp.bswap_buf((uint32_t *) c->slice_bits, (uint32_t *) c->slice_bits,
146  (slice_data_end - slice_data_start + 3) >> 2);
147  init_get_bits(&gb, c->slice_bits, slice_size * 8);
148 
149  prev = 0x80;
150  for (j = sstart; j < send; j++) {
151  for (i = 0; i < width * step; i += step) {
152  if (get_bits_left(&gb) <= 0) {
154  "Slice decoding ran out of bits\n");
155  goto fail;
156  }
157  pix = get_vlc2(&gb, vlc.table, vlc.bits, 4);
158  if (pix < 0) {
159  av_log(c->avctx, AV_LOG_ERROR, "Decoding error\n");
160  goto fail;
161  }
162  if (use_pred) {
163  prev += pix;
164  pix = prev;
165  }
166  dest[i] = pix;
167  }
168  dest += stride;
169  }
170  if (get_bits_left(&gb) > 32)
172  "%d bits left after decoding slice\n", get_bits_left(&gb));
173  }
174 
175  ff_free_vlc(&vlc);
176 
177  return 0;
178 fail:
179  ff_free_vlc(&vlc);
180  return AVERROR_INVALIDDATA;
181 }
182 
183 static void restore_rgb_planes(uint8_t *src, int step, int stride, int width,
184  int height)
185 {
186  int i, j;
187  uint8_t r, g, b;
188 
189  for (j = 0; j < height; j++) {
190  for (i = 0; i < width * step; i += step) {
191  r = src[i];
192  g = src[i + 1];
193  b = src[i + 2];
194  src[i] = r + g - 0x80;
195  src[i + 2] = b + g - 0x80;
196  }
197  src += stride;
198  }
199 }
200 
201 static void restore_median(uint8_t *src, int step, int stride,
202  int width, int height, int slices, int rmode)
203 {
204  int i, j, slice;
205  int A, B, C;
206  uint8_t *bsrc;
207  int slice_start, slice_height;
208  const int cmask = ~rmode;
209 
210  for (slice = 0; slice < slices; slice++) {
211  slice_start = ((slice * height) / slices) & cmask;
212  slice_height = ((((slice + 1) * height) / slices) & cmask) -
213  slice_start;
214 
215  bsrc = src + slice_start * stride;
216 
217  // first line - left neighbour prediction
218  bsrc[0] += 0x80;
219  A = bsrc[0];
220  for (i = step; i < width * step; i += step) {
221  bsrc[i] += A;
222  A = bsrc[i];
223  }
224  bsrc += stride;
225  if (slice_height == 1)
226  continue;
227  // second line - first element has top prediction, the rest uses median
228  C = bsrc[-stride];
229  bsrc[0] += C;
230  A = bsrc[0];
231  for (i = step; i < width * step; i += step) {
232  B = bsrc[i - stride];
233  bsrc[i] += mid_pred(A, B, (uint8_t)(A + B - C));
234  C = B;
235  A = bsrc[i];
236  }
237  bsrc += stride;
238  // the rest of lines use continuous median prediction
239  for (j = 2; j < slice_height; j++) {
240  for (i = 0; i < width * step; i += step) {
241  B = bsrc[i - stride];
242  bsrc[i] += mid_pred(A, B, (uint8_t)(A + B - C));
243  C = B;
244  A = bsrc[i];
245  }
246  bsrc += stride;
247  }
248  }
249 }
250 
251 /* UtVideo interlaced mode treats every two lines as a single one,
252  * so restoring function should take care of possible padding between
253  * two parts of the same "line".
254  */
255 static void restore_median_il(uint8_t *src, int step, int stride,
256  int width, int height, int slices, int rmode)
257 {
258  int i, j, slice;
259  int A, B, C;
260  uint8_t *bsrc;
261  int slice_start, slice_height;
262  const int cmask = ~(rmode ? 3 : 1);
263  const int stride2 = stride << 1;
264 
265  for (slice = 0; slice < slices; slice++) {
266  slice_start = ((slice * height) / slices) & cmask;
267  slice_height = ((((slice + 1) * height) / slices) & cmask) -
268  slice_start;
269  slice_height >>= 1;
270 
271  bsrc = src + slice_start * stride;
272 
273  // first line - left neighbour prediction
274  bsrc[0] += 0x80;
275  A = bsrc[0];
276  for (i = step; i < width * step; i += step) {
277  bsrc[i] += A;
278  A = bsrc[i];
279  }
280  for (i = 0; i < width * step; i += step) {
281  bsrc[stride + i] += A;
282  A = bsrc[stride + i];
283  }
284  bsrc += stride2;
285  if (slice_height == 1)
286  continue;
287  // second line - first element has top prediction, the rest uses median
288  C = bsrc[-stride2];
289  bsrc[0] += C;
290  A = bsrc[0];
291  for (i = step; i < width * step; i += step) {
292  B = bsrc[i - stride2];
293  bsrc[i] += mid_pred(A, B, (uint8_t)(A + B - C));
294  C = B;
295  A = bsrc[i];
296  }
297  for (i = 0; i < width * step; i += step) {
298  B = bsrc[i - stride];
299  bsrc[stride + i] += mid_pred(A, B, (uint8_t)(A + B - C));
300  C = B;
301  A = bsrc[stride + i];
302  }
303  bsrc += stride2;
304  // the rest of lines use continuous median prediction
305  for (j = 2; j < slice_height; j++) {
306  for (i = 0; i < width * step; i += step) {
307  B = bsrc[i - stride2];
308  bsrc[i] += mid_pred(A, B, (uint8_t)(A + B - C));
309  C = B;
310  A = bsrc[i];
311  }
312  for (i = 0; i < width * step; i += step) {
313  B = bsrc[i - stride];
314  bsrc[i + stride] += mid_pred(A, B, (uint8_t)(A + B - C));
315  C = B;
316  A = bsrc[i + stride];
317  }
318  bsrc += stride2;
319  }
320  }
321 }
322 
323 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
324  AVPacket *avpkt)
325 {
326  const uint8_t *buf = avpkt->data;
327  int buf_size = avpkt->size;
328  UtvideoContext *c = avctx->priv_data;
329  int i, j;
330  const uint8_t *plane_start[5];
331  int plane_size, max_slice_size = 0, slice_start, slice_end, slice_size;
332  int ret;
333  GetByteContext gb;
334 
335  if (c->pic.data[0])
336  ff_thread_release_buffer(avctx, &c->pic);
337 
338  c->pic.reference = 1;
340  if ((ret = ff_thread_get_buffer(avctx, &c->pic)) < 0) {
341  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
342  return ret;
343  }
344 
345  ff_thread_finish_setup(avctx);
346 
347  /* parse plane structure to get frame flags and validate slice offsets */
348  bytestream2_init(&gb, buf, buf_size);
349  for (i = 0; i < c->planes; i++) {
350  plane_start[i] = gb.buffer;
351  if (bytestream2_get_bytes_left(&gb) < 256 + 4 * c->slices) {
352  av_log(avctx, AV_LOG_ERROR, "Insufficient data for a plane\n");
353  return AVERROR_INVALIDDATA;
354  }
355  bytestream2_skipu(&gb, 256);
356  slice_start = 0;
357  slice_end = 0;
358  for (j = 0; j < c->slices; j++) {
359  slice_end = bytestream2_get_le32u(&gb);
360  slice_size = slice_end - slice_start;
361  if (slice_end < 0 || slice_size < 0 ||
362  bytestream2_get_bytes_left(&gb) < slice_end) {
363  av_log(avctx, AV_LOG_ERROR, "Incorrect slice size\n");
364  return AVERROR_INVALIDDATA;
365  }
366  slice_start = slice_end;
367  max_slice_size = FFMAX(max_slice_size, slice_size);
368  }
369  plane_size = slice_end;
370  bytestream2_skipu(&gb, plane_size);
371  }
372  plane_start[c->planes] = gb.buffer;
374  av_log(avctx, AV_LOG_ERROR, "Not enough data for frame information\n");
375  return AVERROR_INVALIDDATA;
376  }
377  c->frame_info = bytestream2_get_le32u(&gb);
378  av_log(avctx, AV_LOG_DEBUG, "frame information flags %X\n", c->frame_info);
379 
380  c->frame_pred = (c->frame_info >> 8) & 3;
381 
382  if (c->frame_pred == PRED_GRADIENT) {
383  av_log_ask_for_sample(avctx, "Frame uses gradient prediction\n");
384  return AVERROR_PATCHWELCOME;
385  }
386 
388  max_slice_size + FF_INPUT_BUFFER_PADDING_SIZE);
389 
390  if (!c->slice_bits) {
391  av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer\n");
392  return AVERROR(ENOMEM);
393  }
394 
395  switch (c->avctx->pix_fmt) {
396  case AV_PIX_FMT_RGB24:
397  case AV_PIX_FMT_RGBA:
398  for (i = 0; i < c->planes; i++) {
399  ret = decode_plane(c, i, c->pic.data[0] + ff_ut_rgb_order[i],
400  c->planes, c->pic.linesize[0], avctx->width,
401  avctx->height, plane_start[i],
402  c->frame_pred == PRED_LEFT);
403  if (ret)
404  return ret;
405  if (c->frame_pred == PRED_MEDIAN) {
406  if (!c->interlaced) {
408  c->planes, c->pic.linesize[0], avctx->width,
409  avctx->height, c->slices, 0);
410  } else {
412  c->planes, c->pic.linesize[0],
413  avctx->width, avctx->height, c->slices,
414  0);
415  }
416  }
417  }
418  restore_rgb_planes(c->pic.data[0], c->planes, c->pic.linesize[0],
419  avctx->width, avctx->height);
420  break;
421  case AV_PIX_FMT_YUV420P:
422  for (i = 0; i < 3; i++) {
423  ret = decode_plane(c, i, c->pic.data[i], 1, c->pic.linesize[i],
424  avctx->width >> !!i, avctx->height >> !!i,
425  plane_start[i], c->frame_pred == PRED_LEFT);
426  if (ret)
427  return ret;
428  if (c->frame_pred == PRED_MEDIAN) {
429  if (!c->interlaced) {
430  restore_median(c->pic.data[i], 1, c->pic.linesize[i],
431  avctx->width >> !!i, avctx->height >> !!i,
432  c->slices, !i);
433  } else {
434  restore_median_il(c->pic.data[i], 1, c->pic.linesize[i],
435  avctx->width >> !!i,
436  avctx->height >> !!i,
437  c->slices, !i);
438  }
439  }
440  }
441  break;
442  case AV_PIX_FMT_YUV422P:
443  for (i = 0; i < 3; i++) {
444  ret = decode_plane(c, i, c->pic.data[i], 1, c->pic.linesize[i],
445  avctx->width >> !!i, avctx->height,
446  plane_start[i], c->frame_pred == PRED_LEFT);
447  if (ret)
448  return ret;
449  if (c->frame_pred == PRED_MEDIAN) {
450  if (!c->interlaced) {
451  restore_median(c->pic.data[i], 1, c->pic.linesize[i],
452  avctx->width >> !!i, avctx->height,
453  c->slices, 0);
454  } else {
455  restore_median_il(c->pic.data[i], 1, c->pic.linesize[i],
456  avctx->width >> !!i, avctx->height,
457  c->slices, 0);
458  }
459  }
460  }
461  break;
462  }
463 
464  c->pic.key_frame = 1;
466  c->pic.interlaced_frame = !!c->interlaced;
467 
468  *got_frame = 1;
469  *(AVFrame*)data = c->pic;
470 
471  /* always report that the buffer was completely consumed */
472  return buf_size;
473 }
474 
476 {
477  UtvideoContext * const c = avctx->priv_data;
478 
479  c->avctx = avctx;
480 
481  ff_dsputil_init(&c->dsp, avctx);
482 
483  if (avctx->extradata_size < 16) {
484  av_log(avctx, AV_LOG_ERROR,
485  "Insufficient extradata size %d, should be at least 16\n",
486  avctx->extradata_size);
487  return AVERROR_INVALIDDATA;
488  }
489 
490  av_log(avctx, AV_LOG_DEBUG, "Encoder version %d.%d.%d.%d\n",
491  avctx->extradata[3], avctx->extradata[2],
492  avctx->extradata[1], avctx->extradata[0]);
493  av_log(avctx, AV_LOG_DEBUG, "Original format %X\n",
494  AV_RB32(avctx->extradata + 4));
495  c->frame_info_size = AV_RL32(avctx->extradata + 8);
496  c->flags = AV_RL32(avctx->extradata + 12);
497 
498  if (c->frame_info_size != 4)
499  av_log_ask_for_sample(avctx, "Frame info is not 4 bytes\n");
500  av_log(avctx, AV_LOG_DEBUG, "Encoding parameters %08X\n", c->flags);
501  c->slices = (c->flags >> 24) + 1;
502  c->compression = c->flags & 1;
503  c->interlaced = c->flags & 0x800;
504 
505  c->slice_bits_size = 0;
506 
507  switch (avctx->codec_tag) {
508  case MKTAG('U', 'L', 'R', 'G'):
509  c->planes = 3;
510  avctx->pix_fmt = AV_PIX_FMT_RGB24;
511  break;
512  case MKTAG('U', 'L', 'R', 'A'):
513  c->planes = 4;
514  avctx->pix_fmt = AV_PIX_FMT_RGBA;
515  break;
516  case MKTAG('U', 'L', 'Y', '0'):
517  c->planes = 3;
518  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
519  break;
520  case MKTAG('U', 'L', 'Y', '2'):
521  c->planes = 3;
522  avctx->pix_fmt = AV_PIX_FMT_YUV422P;
523  break;
524  default:
525  av_log(avctx, AV_LOG_ERROR, "Unknown Ut Video FOURCC provided (%08X)\n",
526  avctx->codec_tag);
527  return AVERROR_INVALIDDATA;
528  }
529 
530  return 0;
531 }
532 
534 {
535  UtvideoContext * const c = avctx->priv_data;
536 
537  if (c->pic.data[0])
538  ff_thread_release_buffer(avctx, &c->pic);
539 
540  av_freep(&c->slice_bits);
541 
542  return 0;
543 }
544 
546  .name = "utvideo",
547  .type = AVMEDIA_TYPE_VIDEO,
548  .id = AV_CODEC_ID_UTVIDEO,
549  .priv_data_size = sizeof(UtvideoContext),
550  .init = decode_init,
551  .close = decode_end,
552  .decode = decode_frame,
553  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
554  .long_name = NULL_IF_CONFIG_SMALL("Ut Video"),
555 };