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lagarith.c
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1 /*
2  * Lagarith lossless decoder
3  * Copyright (c) 2009 Nathan Caldwell <saintdev (at) gmail.com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Lagarith lossless decoder
25  * @author Nathan Caldwell
26  */
27 
28 #include <inttypes.h>
29 
30 #include "avcodec.h"
31 #include "get_bits.h"
32 #include "mathops.h"
33 #include "huffyuvdsp.h"
34 #include "lagarithrac.h"
35 #include "thread.h"
36 
38  FRAME_RAW = 1, /**< uncompressed */
39  FRAME_U_RGB24 = 2, /**< unaligned RGB24 */
40  FRAME_ARITH_YUY2 = 3, /**< arithmetic coded YUY2 */
41  FRAME_ARITH_RGB24 = 4, /**< arithmetic coded RGB24 */
42  FRAME_SOLID_GRAY = 5, /**< solid grayscale color frame */
43  FRAME_SOLID_COLOR = 6, /**< solid non-grayscale color frame */
44  FRAME_OLD_ARITH_RGB = 7, /**< obsolete arithmetic coded RGB (no longer encoded by upstream since version 1.1.0) */
45  FRAME_ARITH_RGBA = 8, /**< arithmetic coded RGBA */
46  FRAME_SOLID_RGBA = 9, /**< solid RGBA color frame */
47  FRAME_ARITH_YV12 = 10, /**< arithmetic coded YV12 */
48  FRAME_REDUCED_RES = 11, /**< reduced resolution YV12 frame */
49 };
50 
51 typedef struct LagarithContext {
54  int zeros; /**< number of consecutive zero bytes encountered */
55  int zeros_rem; /**< number of zero bytes remaining to output */
60 
61 /**
62  * Compute the 52bit mantissa of 1/(double)denom.
63  * This crazy format uses floats in an entropy coder and we have to match x86
64  * rounding exactly, thus ordinary floats aren't portable enough.
65  * @param denom denominator
66  * @return 52bit mantissa
67  * @see softfloat_mul
68  */
69 static uint64_t softfloat_reciprocal(uint32_t denom)
70 {
71  int shift = av_log2(denom - 1) + 1;
72  uint64_t ret = (1ULL << 52) / denom;
73  uint64_t err = (1ULL << 52) - ret * denom;
74  ret <<= shift;
75  err <<= shift;
76  err += denom / 2;
77  return ret + err / denom;
78 }
79 
80 /**
81  * (uint32_t)(x*f), where f has the given mantissa, and exponent 0
82  * Used in combination with softfloat_reciprocal computes x/(double)denom.
83  * @param x 32bit integer factor
84  * @param mantissa mantissa of f with exponent 0
85  * @return 32bit integer value (x*f)
86  * @see softfloat_reciprocal
87  */
88 static uint32_t softfloat_mul(uint32_t x, uint64_t mantissa)
89 {
90  uint64_t l = x * (mantissa & 0xffffffff);
91  uint64_t h = x * (mantissa >> 32);
92  h += l >> 32;
93  l &= 0xffffffff;
94  l += 1 << av_log2(h >> 21);
95  h += l >> 32;
96  return h >> 20;
97 }
98 
99 static uint8_t lag_calc_zero_run(int8_t x)
100 {
101  return (x << 1) ^ (x >> 7);
102 }
103 
104 static int lag_decode_prob(GetBitContext *gb, uint32_t *value)
105 {
106  static const uint8_t series[] = { 1, 2, 3, 5, 8, 13, 21 };
107  int i;
108  int bit = 0;
109  int bits = 0;
110  int prevbit = 0;
111  unsigned val;
112 
113  for (i = 0; i < 7; i++) {
114  if (prevbit && bit)
115  break;
116  prevbit = bit;
117  bit = get_bits1(gb);
118  if (bit && !prevbit)
119  bits += series[i];
120  }
121  bits--;
122  if (bits < 0 || bits > 31) {
123  *value = 0;
124  return -1;
125  } else if (bits == 0) {
126  *value = 0;
127  return 0;
128  }
129 
130  val = get_bits_long(gb, bits);
131  val |= 1U << bits;
132 
133  *value = val - 1;
134 
135  return 0;
136 }
137 
139 {
140  int i, j, scale_factor;
141  unsigned prob, cumulative_target;
142  unsigned cumul_prob = 0;
143  unsigned scaled_cumul_prob = 0;
144 
145  rac->prob[0] = 0;
146  rac->prob[257] = UINT_MAX;
147  /* Read probabilities from bitstream */
148  for (i = 1; i < 257; i++) {
149  if (lag_decode_prob(gb, &rac->prob[i]) < 0) {
150  av_log(rac->avctx, AV_LOG_ERROR, "Invalid probability encountered.\n");
151  return -1;
152  }
153  if ((uint64_t)cumul_prob + rac->prob[i] > UINT_MAX) {
154  av_log(rac->avctx, AV_LOG_ERROR, "Integer overflow encountered in cumulative probability calculation.\n");
155  return -1;
156  }
157  cumul_prob += rac->prob[i];
158  if (!rac->prob[i]) {
159  if (lag_decode_prob(gb, &prob)) {
160  av_log(rac->avctx, AV_LOG_ERROR, "Invalid probability run encountered.\n");
161  return -1;
162  }
163  if (prob > 256 - i)
164  prob = 256 - i;
165  for (j = 0; j < prob; j++)
166  rac->prob[++i] = 0;
167  }
168  }
169 
170  if (!cumul_prob) {
171  av_log(rac->avctx, AV_LOG_ERROR, "All probabilities are 0!\n");
172  return -1;
173  }
174 
175  /* Scale probabilities so cumulative probability is an even power of 2. */
176  scale_factor = av_log2(cumul_prob);
177 
178  if (cumul_prob & (cumul_prob - 1)) {
179  uint64_t mul = softfloat_reciprocal(cumul_prob);
180  for (i = 1; i <= 128; i++) {
181  rac->prob[i] = softfloat_mul(rac->prob[i], mul);
182  scaled_cumul_prob += rac->prob[i];
183  }
184  if (scaled_cumul_prob <= 0) {
185  av_log(rac->avctx, AV_LOG_ERROR, "Scaled probabilities invalid\n");
186  return AVERROR_INVALIDDATA;
187  }
188  for (; i < 257; i++) {
189  rac->prob[i] = softfloat_mul(rac->prob[i], mul);
190  scaled_cumul_prob += rac->prob[i];
191  }
192 
193  scale_factor++;
194  cumulative_target = 1 << scale_factor;
195 
196  if (scaled_cumul_prob > cumulative_target) {
197  av_log(rac->avctx, AV_LOG_ERROR,
198  "Scaled probabilities are larger than target!\n");
199  return -1;
200  }
201 
202  scaled_cumul_prob = cumulative_target - scaled_cumul_prob;
203 
204  for (i = 1; scaled_cumul_prob; i = (i & 0x7f) + 1) {
205  if (rac->prob[i]) {
206  rac->prob[i]++;
207  scaled_cumul_prob--;
208  }
209  /* Comment from reference source:
210  * if (b & 0x80 == 0) { // order of operations is 'wrong'; it has been left this way
211  * // since the compression change is negligible and fixing it
212  * // breaks backwards compatibility
213  * b =- (signed int)b;
214  * b &= 0xFF;
215  * } else {
216  * b++;
217  * b &= 0x7f;
218  * }
219  */
220  }
221  }
222 
223  rac->scale = scale_factor;
224 
225  /* Fill probability array with cumulative probability for each symbol. */
226  for (i = 1; i < 257; i++)
227  rac->prob[i] += rac->prob[i - 1];
228 
229  return 0;
230 }
231 
232 static void add_lag_median_prediction(uint8_t *dst, uint8_t *src1,
233  uint8_t *diff, int w, int *left,
234  int *left_top)
235 {
236  /* This is almost identical to add_hfyu_median_pred in huffyuvdsp.h.
237  * However the &0xFF on the gradient predictor yealds incorrect output
238  * for lagarith.
239  */
240  int i;
241  uint8_t l, lt;
242 
243  l = *left;
244  lt = *left_top;
245 
246  for (i = 0; i < w; i++) {
247  l = mid_pred(l, src1[i], l + src1[i] - lt) + diff[i];
248  lt = src1[i];
249  dst[i] = l;
250  }
251 
252  *left = l;
253  *left_top = lt;
254 }
255 
257  int width, int stride, int line)
258 {
259  int L, TL;
260 
261  if (!line) {
262  /* Left prediction only for first line */
263  L = l->hdsp.add_hfyu_left_pred(buf, buf, width, 0);
264  } else {
265  /* Left pixel is actually prev_row[width] */
266  L = buf[width - stride - 1];
267 
268  if (line == 1) {
269  /* Second line, left predict first pixel, the rest of the line is median predicted
270  * NOTE: In the case of RGB this pixel is top predicted */
271  TL = l->avctx->pix_fmt == AV_PIX_FMT_YUV420P ? buf[-stride] : L;
272  } else {
273  /* Top left is 2 rows back, last pixel */
274  TL = buf[width - (2 * stride) - 1];
275  }
276 
277  add_lag_median_prediction(buf, buf - stride, buf,
278  width, &L, &TL);
279  }
280 }
281 
283  int width, int stride, int line,
284  int is_luma)
285 {
286  int L, TL;
287 
288  if (!line) {
289  L= buf[0];
290  if (is_luma)
291  buf[0] = 0;
292  l->hdsp.add_hfyu_left_pred(buf, buf, width, 0);
293  if (is_luma)
294  buf[0] = L;
295  return;
296  }
297  if (line == 1) {
298  const int HEAD = is_luma ? 4 : 2;
299  int i;
300 
301  L = buf[width - stride - 1];
302  TL = buf[HEAD - stride - 1];
303  for (i = 0; i < HEAD; i++) {
304  L += buf[i];
305  buf[i] = L;
306  }
307  for (; i < width; i++) {
308  L = mid_pred(L & 0xFF, buf[i - stride], (L + buf[i - stride] - TL) & 0xFF) + buf[i];
309  TL = buf[i - stride];
310  buf[i] = L;
311  }
312  } else {
313  TL = buf[width - (2 * stride) - 1];
314  L = buf[width - stride - 1];
315  l->hdsp.add_hfyu_median_pred(buf, buf - stride, buf, width, &L, &TL);
316  }
317 }
318 
320  uint8_t *dst, int width, int stride,
321  int esc_count)
322 {
323  int i = 0;
324  int ret = 0;
325 
326  if (!esc_count)
327  esc_count = -1;
328 
329  /* Output any zeros remaining from the previous run */
330 handle_zeros:
331  if (l->zeros_rem) {
332  int count = FFMIN(l->zeros_rem, width - i);
333  memset(dst + i, 0, count);
334  i += count;
335  l->zeros_rem -= count;
336  }
337 
338  while (i < width) {
339  dst[i] = lag_get_rac(rac);
340  ret++;
341 
342  if (dst[i])
343  l->zeros = 0;
344  else
345  l->zeros++;
346 
347  i++;
348  if (l->zeros == esc_count) {
349  int index = lag_get_rac(rac);
350  ret++;
351 
352  l->zeros = 0;
353 
354  l->zeros_rem = lag_calc_zero_run(index);
355  goto handle_zeros;
356  }
357  }
358  return ret;
359 }
360 
362  const uint8_t *src, const uint8_t *src_end,
363  int width, int esc_count)
364 {
365  int i = 0;
366  int count;
367  uint8_t zero_run = 0;
368  const uint8_t *src_start = src;
369  uint8_t mask1 = -(esc_count < 2);
370  uint8_t mask2 = -(esc_count < 3);
371  uint8_t *end = dst + (width - 2);
372 
373  avpriv_request_sample(l->avctx, "zero_run_line");
374 
375  memset(dst, 0, width);
376 
377 output_zeros:
378  if (l->zeros_rem) {
379  count = FFMIN(l->zeros_rem, width - i);
380  if (end - dst < count) {
381  av_log(l->avctx, AV_LOG_ERROR, "Too many zeros remaining.\n");
382  return AVERROR_INVALIDDATA;
383  }
384 
385  memset(dst, 0, count);
386  l->zeros_rem -= count;
387  dst += count;
388  }
389 
390  while (dst < end) {
391  i = 0;
392  while (!zero_run && dst + i < end) {
393  i++;
394  if (i+2 >= src_end - src)
395  return AVERROR_INVALIDDATA;
396  zero_run =
397  !(src[i] | (src[i + 1] & mask1) | (src[i + 2] & mask2));
398  }
399  if (zero_run) {
400  zero_run = 0;
401  i += esc_count;
402  memcpy(dst, src, i);
403  dst += i;
404  l->zeros_rem = lag_calc_zero_run(src[i]);
405 
406  src += i + 1;
407  goto output_zeros;
408  } else {
409  memcpy(dst, src, i);
410  src += i;
411  dst += i;
412  }
413  }
414  return src - src_start;
415 }
416 
417 
418 
420  int width, int height, int stride,
421  const uint8_t *src, int src_size)
422 {
423  int i = 0;
424  int read = 0;
425  uint32_t length;
426  uint32_t offset = 1;
427  int esc_count;
428  GetBitContext gb;
429  lag_rac rac;
430  const uint8_t *src_end = src + src_size;
431  int ret;
432 
433  rac.avctx = l->avctx;
434  l->zeros = 0;
435 
436  if(src_size < 2)
437  return AVERROR_INVALIDDATA;
438 
439  esc_count = src[0];
440  if (esc_count < 4) {
441  length = width * height;
442  if(src_size < 5)
443  return AVERROR_INVALIDDATA;
444  if (esc_count && AV_RL32(src + 1) < length) {
445  length = AV_RL32(src + 1);
446  offset += 4;
447  }
448 
449  if ((ret = init_get_bits8(&gb, src + offset, src_size - offset)) < 0)
450  return ret;
451 
452  if (lag_read_prob_header(&rac, &gb) < 0)
453  return -1;
454 
455  ff_lag_rac_init(&rac, &gb, length - stride);
456 
457  for (i = 0; i < height; i++)
458  read += lag_decode_line(l, &rac, dst + (i * stride), width,
459  stride, esc_count);
460 
461  if (read > length)
463  "Output more bytes than length (%d of %"PRIu32")\n", read,
464  length);
465  } else if (esc_count < 8) {
466  esc_count -= 4;
467  src ++;
468  src_size --;
469  if (esc_count > 0) {
470  /* Zero run coding only, no range coding. */
471  for (i = 0; i < height; i++) {
472  int res = lag_decode_zero_run_line(l, dst + (i * stride), src,
473  src_end, width, esc_count);
474  if (res < 0)
475  return res;
476  src += res;
477  }
478  } else {
479  if (src_size < width * height)
480  return AVERROR_INVALIDDATA; // buffer not big enough
481  /* Plane is stored uncompressed */
482  for (i = 0; i < height; i++) {
483  memcpy(dst + (i * stride), src, width);
484  src += width;
485  }
486  }
487  } else if (esc_count == 0xff) {
488  /* Plane is a solid run of given value */
489  for (i = 0; i < height; i++)
490  memset(dst + i * stride, src[1], width);
491  /* Do not apply prediction.
492  Note: memset to 0 above, setting first value to src[1]
493  and applying prediction gives the same result. */
494  return 0;
495  } else {
497  "Invalid zero run escape code! (%#x)\n", esc_count);
498  return -1;
499  }
500 
501  if (l->avctx->pix_fmt != AV_PIX_FMT_YUV422P) {
502  for (i = 0; i < height; i++) {
503  lag_pred_line(l, dst, width, stride, i);
504  dst += stride;
505  }
506  } else {
507  for (i = 0; i < height; i++) {
508  lag_pred_line_yuy2(l, dst, width, stride, i,
509  width == l->avctx->width);
510  dst += stride;
511  }
512  }
513 
514  return 0;
515 }
516 
517 /**
518  * Decode a frame.
519  * @param avctx codec context
520  * @param data output AVFrame
521  * @param data_size size of output data or 0 if no picture is returned
522  * @param avpkt input packet
523  * @return number of consumed bytes on success or negative if decode fails
524  */
526  void *data, int *got_frame, AVPacket *avpkt)
527 {
528  const uint8_t *buf = avpkt->data;
529  unsigned int buf_size = avpkt->size;
530  LagarithContext *l = avctx->priv_data;
531  ThreadFrame frame = { .f = data };
532  AVFrame *const p = data;
533  uint8_t frametype = 0;
534  uint32_t offset_gu = 0, offset_bv = 0, offset_ry = 9;
535  uint32_t offs[4];
536  uint8_t *srcs[4], *dst;
537  int i, j, planes = 3;
538  int ret;
539 
540  p->key_frame = 1;
541 
542  frametype = buf[0];
543 
544  offset_gu = AV_RL32(buf + 1);
545  offset_bv = AV_RL32(buf + 5);
546 
547  switch (frametype) {
548  case FRAME_SOLID_RGBA:
549  avctx->pix_fmt = AV_PIX_FMT_RGB32;
550  case FRAME_SOLID_GRAY:
551  if (frametype == FRAME_SOLID_GRAY)
552  if (avctx->bits_per_coded_sample == 24) {
553  avctx->pix_fmt = AV_PIX_FMT_RGB24;
554  } else {
555  avctx->pix_fmt = AV_PIX_FMT_0RGB32;
556  planes = 4;
557  }
558 
559  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
560  return ret;
561 
562  dst = p->data[0];
563  if (frametype == FRAME_SOLID_RGBA) {
564  for (j = 0; j < avctx->height; j++) {
565  for (i = 0; i < avctx->width; i++)
566  AV_WN32(dst + i * 4, offset_gu);
567  dst += p->linesize[0];
568  }
569  } else {
570  for (j = 0; j < avctx->height; j++) {
571  memset(dst, buf[1], avctx->width * planes);
572  dst += p->linesize[0];
573  }
574  }
575  break;
576  case FRAME_SOLID_COLOR:
577  if (avctx->bits_per_coded_sample == 24) {
578  avctx->pix_fmt = AV_PIX_FMT_RGB24;
579  } else {
580  avctx->pix_fmt = AV_PIX_FMT_RGB32;
581  offset_gu |= 0xFFU << 24;
582  }
583 
584  if ((ret = ff_thread_get_buffer(avctx, &frame,0)) < 0)
585  return ret;
586 
587  dst = p->data[0];
588  for (j = 0; j < avctx->height; j++) {
589  for (i = 0; i < avctx->width; i++)
590  if (avctx->bits_per_coded_sample == 24) {
591  AV_WB24(dst + i * 3, offset_gu);
592  } else {
593  AV_WN32(dst + i * 4, offset_gu);
594  }
595  dst += p->linesize[0];
596  }
597  break;
598  case FRAME_ARITH_RGBA:
599  avctx->pix_fmt = AV_PIX_FMT_RGB32;
600  planes = 4;
601  offset_ry += 4;
602  offs[3] = AV_RL32(buf + 9);
603  case FRAME_ARITH_RGB24:
604  case FRAME_U_RGB24:
605  if (frametype == FRAME_ARITH_RGB24 || frametype == FRAME_U_RGB24)
606  avctx->pix_fmt = AV_PIX_FMT_RGB24;
607 
608  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
609  return ret;
610 
611  offs[0] = offset_bv;
612  offs[1] = offset_gu;
613  offs[2] = offset_ry;
614 
615  l->rgb_stride = FFALIGN(avctx->width, 16);
617  l->rgb_stride * avctx->height * planes + 1);
618  if (!l->rgb_planes) {
619  av_log(avctx, AV_LOG_ERROR, "cannot allocate temporary buffer\n");
620  return AVERROR(ENOMEM);
621  }
622  for (i = 0; i < planes; i++)
623  srcs[i] = l->rgb_planes + (i + 1) * l->rgb_stride * avctx->height - l->rgb_stride;
624  for (i = 0; i < planes; i++)
625  if (buf_size <= offs[i]) {
626  av_log(avctx, AV_LOG_ERROR,
627  "Invalid frame offsets\n");
628  return AVERROR_INVALIDDATA;
629  }
630 
631  for (i = 0; i < planes; i++)
632  lag_decode_arith_plane(l, srcs[i],
633  avctx->width, avctx->height,
634  -l->rgb_stride, buf + offs[i],
635  buf_size - offs[i]);
636  dst = p->data[0];
637  for (i = 0; i < planes; i++)
638  srcs[i] = l->rgb_planes + i * l->rgb_stride * avctx->height;
639  for (j = 0; j < avctx->height; j++) {
640  for (i = 0; i < avctx->width; i++) {
641  uint8_t r, g, b, a;
642  r = srcs[0][i];
643  g = srcs[1][i];
644  b = srcs[2][i];
645  r += g;
646  b += g;
647  if (frametype == FRAME_ARITH_RGBA) {
648  a = srcs[3][i];
649  AV_WN32(dst + i * 4, MKBETAG(a, r, g, b));
650  } else {
651  dst[i * 3 + 0] = r;
652  dst[i * 3 + 1] = g;
653  dst[i * 3 + 2] = b;
654  }
655  }
656  dst += p->linesize[0];
657  for (i = 0; i < planes; i++)
658  srcs[i] += l->rgb_stride;
659  }
660  break;
661  case FRAME_ARITH_YUY2:
662  avctx->pix_fmt = AV_PIX_FMT_YUV422P;
663 
664  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
665  return ret;
666 
667  if (offset_ry >= buf_size ||
668  offset_gu >= buf_size ||
669  offset_bv >= buf_size) {
670  av_log(avctx, AV_LOG_ERROR,
671  "Invalid frame offsets\n");
672  return AVERROR_INVALIDDATA;
673  }
674 
675  lag_decode_arith_plane(l, p->data[0], avctx->width, avctx->height,
676  p->linesize[0], buf + offset_ry,
677  buf_size - offset_ry);
678  lag_decode_arith_plane(l, p->data[1], (avctx->width + 1) / 2,
679  avctx->height, p->linesize[1],
680  buf + offset_gu, buf_size - offset_gu);
681  lag_decode_arith_plane(l, p->data[2], (avctx->width + 1) / 2,
682  avctx->height, p->linesize[2],
683  buf + offset_bv, buf_size - offset_bv);
684  break;
685  case FRAME_ARITH_YV12:
686  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
687 
688  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
689  return ret;
690  if (buf_size <= offset_ry || buf_size <= offset_gu || buf_size <= offset_bv) {
691  return AVERROR_INVALIDDATA;
692  }
693 
694  if (offset_ry >= buf_size ||
695  offset_gu >= buf_size ||
696  offset_bv >= buf_size) {
697  av_log(avctx, AV_LOG_ERROR,
698  "Invalid frame offsets\n");
699  return AVERROR_INVALIDDATA;
700  }
701 
702  lag_decode_arith_plane(l, p->data[0], avctx->width, avctx->height,
703  p->linesize[0], buf + offset_ry,
704  buf_size - offset_ry);
705  lag_decode_arith_plane(l, p->data[2], (avctx->width + 1) / 2,
706  (avctx->height + 1) / 2, p->linesize[2],
707  buf + offset_gu, buf_size - offset_gu);
708  lag_decode_arith_plane(l, p->data[1], (avctx->width + 1) / 2,
709  (avctx->height + 1) / 2, p->linesize[1],
710  buf + offset_bv, buf_size - offset_bv);
711  break;
712  default:
713  av_log(avctx, AV_LOG_ERROR,
714  "Unsupported Lagarith frame type: %#"PRIx8"\n", frametype);
715  return AVERROR_PATCHWELCOME;
716  }
717 
718  *got_frame = 1;
719 
720  return buf_size;
721 }
722 
724 {
725  LagarithContext *l = avctx->priv_data;
726  l->avctx = avctx;
727 
729 
730  return 0;
731 }
732 
734 {
735  LagarithContext *l = avctx->priv_data;
736 
737  av_freep(&l->rgb_planes);
738 
739  return 0;
740 }
741 
743  .name = "lagarith",
744  .long_name = NULL_IF_CONFIG_SMALL("Lagarith lossless"),
745  .type = AVMEDIA_TYPE_VIDEO,
746  .id = AV_CODEC_ID_LAGARITH,
747  .priv_data_size = sizeof(LagarithContext),
751  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
752 };