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lcldec.c
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1 /*
2  * LCL (LossLess Codec Library) Codec
3  * Copyright (c) 2002-2004 Roberto Togni
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  * LCL (LossLess Codec Library) Video Codec
25  * Decoder for MSZH and ZLIB codecs
26  * Experimental encoder for ZLIB RGB24
27  *
28  * Fourcc: MSZH, ZLIB
29  *
30  * Original Win32 dll:
31  * Ver2.23 By Kenji Oshima 2000.09.20
32  * avimszh.dll, avizlib.dll
33  *
34  * A description of the decoding algorithm can be found here:
35  * http://www.pcisys.net/~melanson/codecs
36  *
37  * Supports: BGR24 (RGB 24bpp)
38  *
39  */
40 
41 #include <stdio.h>
42 #include <stdlib.h>
43 
44 #include "libavutil/mem.h"
45 #include "libavutil/pixdesc.h"
46 #include "avcodec.h"
47 #include "bytestream.h"
48 #include "internal.h"
49 #include "lcl.h"
50 
51 #if CONFIG_ZLIB_DECODER
52 #include <zlib.h>
53 #endif
54 
55 /*
56  * Decoder context
57  */
58 typedef struct LclDecContext {
59  // Image type
60  int imgtype;
61  // Compression type
62  int compression;
63  // Flags
64  int flags;
65  // Decompressed data size
66  unsigned int decomp_size;
67  // Decompression buffer
68  unsigned char* decomp_buf;
69 #if CONFIG_ZLIB_DECODER
70  z_stream zstream;
71 #endif
72 } LclDecContext;
73 
74 
75 /**
76  * @param srcptr compressed source buffer, must be padded with at least 5 extra bytes
77  * @param destptr must be padded sufficiently for av_memcpy_backptr
78  */
79 static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsigned char * destptr, unsigned int destsize)
80 {
81  unsigned char *destptr_bak = destptr;
82  unsigned char *destptr_end = destptr + destsize;
83  const unsigned char *srcptr_end = srcptr + srclen;
84  unsigned mask = *srcptr++;
85  unsigned maskbit = 0x80;
86 
87  while (srcptr < srcptr_end && destptr < destptr_end) {
88  if (!(mask & maskbit)) {
89  memcpy(destptr, srcptr, 4);
90  destptr += 4;
91  srcptr += 4;
92  } else {
93  unsigned ofs = bytestream_get_le16(&srcptr);
94  unsigned cnt = (ofs >> 11) + 1;
95  ofs &= 0x7ff;
96  ofs = FFMIN(ofs, destptr - destptr_bak);
97  cnt *= 4;
98  cnt = FFMIN(cnt, destptr_end - destptr);
99  if (ofs) {
100  av_memcpy_backptr(destptr, ofs, cnt);
101  } else {
102  // Not known what the correct behaviour is, but
103  // this at least avoids uninitialized data.
104  memset(destptr, 0, cnt);
105  }
106  destptr += cnt;
107  }
108  maskbit >>= 1;
109  if (!maskbit) {
110  mask = *srcptr++;
111  while (!mask) {
112  if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;
113  memcpy(destptr, srcptr, 32);
114  destptr += 32;
115  srcptr += 32;
116  mask = *srcptr++;
117  }
118  maskbit = 0x80;
119  }
120  }
121 
122  return destptr - destptr_bak;
123 }
124 
125 
126 #if CONFIG_ZLIB_DECODER
127 /**
128  * @brief decompress a zlib-compressed data block into decomp_buf
129  * @param src compressed input buffer
130  * @param src_len data length in input buffer
131  * @param offset offset in decomp_buf
132  * @param expected expected decompressed length
133  */
134 static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)
135 {
136  LclDecContext *c = avctx->priv_data;
137  int zret = inflateReset(&c->zstream);
138  if (zret != Z_OK) {
139  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
140  return AVERROR_UNKNOWN;
141  }
142  c->zstream.next_in = (uint8_t *)src;
143  c->zstream.avail_in = src_len;
144  c->zstream.next_out = c->decomp_buf + offset;
145  c->zstream.avail_out = c->decomp_size - offset;
146  zret = inflate(&c->zstream, Z_FINISH);
147  if (zret != Z_OK && zret != Z_STREAM_END) {
148  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
149  return AVERROR_UNKNOWN;
150  }
151  if (expected != (unsigned int)c->zstream.total_out) {
152  av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %lu)\n",
153  expected, c->zstream.total_out);
154  return AVERROR_UNKNOWN;
155  }
156  return c->zstream.total_out;
157 }
158 #endif
159 
160 
161 /*
162  *
163  * Decode a frame
164  *
165  */
166 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
167 {
168  AVFrame *frame = data;
169  const uint8_t *buf = avpkt->data;
170  int buf_size = avpkt->size;
171  LclDecContext * const c = avctx->priv_data;
172  unsigned char *encoded = (unsigned char *)buf;
173  unsigned int pixel_ptr;
174  int row, col;
175  unsigned char *outptr;
176  uint8_t *y_out, *u_out, *v_out;
177  unsigned int width = avctx->width; // Real image width
178  unsigned int height = avctx->height; // Real image height
179  unsigned int mszh_dlen;
180  unsigned char yq, y1q, uq, vq;
181  int uqvq, ret;
182  unsigned int mthread_inlen, mthread_outlen;
183  unsigned int len = buf_size;
184 
185  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
186  return ret;
187 
188  outptr = frame->data[0]; // Output image pointer
189 
190  /* Decompress frame */
191  switch (avctx->codec_id) {
192  case AV_CODEC_ID_MSZH:
193  switch (c->compression) {
194  case COMP_MSZH:
195  if (c->imgtype == IMGTYPE_RGB24 && len == width * height * 3) {
196  ;
197  } else if (c->flags & FLAG_MULTITHREAD) {
198  mthread_inlen = AV_RL32(encoded);
199  if (len < 8) {
200  av_log(avctx, AV_LOG_ERROR, "len %d is too small\n", len);
201  return AVERROR_INVALIDDATA;
202  }
203  mthread_inlen = FFMIN(mthread_inlen, len - 8);
204  mthread_outlen = AV_RL32(encoded+4);
205  mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
206  mszh_dlen = mszh_decomp(encoded + 8, mthread_inlen, c->decomp_buf, c->decomp_size);
207  if (mthread_outlen != mszh_dlen) {
208  av_log(avctx, AV_LOG_ERROR, "Mthread1 decoded size differs (%d != %d)\n",
209  mthread_outlen, mszh_dlen);
210  return AVERROR_INVALIDDATA;
211  }
212  mszh_dlen = mszh_decomp(encoded + 8 + mthread_inlen, len - 8 - mthread_inlen,
213  c->decomp_buf + mthread_outlen, c->decomp_size - mthread_outlen);
214  if (mthread_outlen != mszh_dlen) {
215  av_log(avctx, AV_LOG_ERROR, "Mthread2 decoded size differs (%d != %d)\n",
216  mthread_outlen, mszh_dlen);
217  return AVERROR_INVALIDDATA;
218  }
219  encoded = c->decomp_buf;
220  len = c->decomp_size;
221  } else {
222  mszh_dlen = mszh_decomp(encoded, len, c->decomp_buf, c->decomp_size);
223  if (c->decomp_size != mszh_dlen) {
224  av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %d)\n",
225  c->decomp_size, mszh_dlen);
226  return AVERROR_INVALIDDATA;
227  }
228  encoded = c->decomp_buf;
229  len = mszh_dlen;
230  }
231  break;
232  case COMP_MSZH_NOCOMP: {
233  int bppx2;
234  switch (c->imgtype) {
235  case IMGTYPE_YUV111:
236  case IMGTYPE_RGB24:
237  bppx2 = 6;
238  break;
239  case IMGTYPE_YUV422:
240  case IMGTYPE_YUV211:
241  bppx2 = 4;
242  break;
243  case IMGTYPE_YUV411:
244  case IMGTYPE_YUV420:
245  bppx2 = 3;
246  break;
247  default:
248  bppx2 = 0; // will error out below
249  break;
250  }
251  if (len < ((width * height * bppx2) >> 1))
252  return AVERROR_INVALIDDATA;
253  break;
254  }
255  default:
256  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown MSZH compression in frame decoder.\n");
257  return AVERROR_INVALIDDATA;
258  }
259  break;
260 #if CONFIG_ZLIB_DECODER
261  case AV_CODEC_ID_ZLIB:
262  /* Using the original dll with normal compression (-1) and RGB format
263  * gives a file with ZLIB fourcc, but frame is really uncompressed.
264  * To be sure that's true check also frame size */
265  if (c->compression == COMP_ZLIB_NORMAL && c->imgtype == IMGTYPE_RGB24 &&
266  len == width * height * 3) {
267  if (c->flags & FLAG_PNGFILTER) {
268  memcpy(c->decomp_buf, encoded, len);
269  encoded = c->decomp_buf;
270  } else {
271  break;
272  }
273  } else if (c->flags & FLAG_MULTITHREAD) {
274  mthread_inlen = AV_RL32(encoded);
275  mthread_inlen = FFMIN(mthread_inlen, len - 8);
276  mthread_outlen = AV_RL32(encoded+4);
277  mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
278  ret = zlib_decomp(avctx, encoded + 8, mthread_inlen, 0, mthread_outlen);
279  if (ret < 0) return ret;
280  ret = zlib_decomp(avctx, encoded + 8 + mthread_inlen, len - 8 - mthread_inlen,
281  mthread_outlen, mthread_outlen);
282  if (ret < 0) return ret;
283  } else {
284  int ret = zlib_decomp(avctx, encoded, len, 0, c->decomp_size);
285  if (ret < 0) return ret;
286  }
287  encoded = c->decomp_buf;
288  len = c->decomp_size;
289  break;
290 #endif
291  default:
292  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in frame decoder compression switch.\n");
293  return AVERROR_INVALIDDATA;
294  }
295 
296 
297  /* Apply PNG filter */
298  if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER)) {
299  switch (c->imgtype) {
300  case IMGTYPE_YUV111:
301  case IMGTYPE_RGB24:
302  for (row = 0; row < height; row++) {
303  pixel_ptr = row * width * 3;
304  yq = encoded[pixel_ptr++];
305  uqvq = AV_RL16(encoded+pixel_ptr);
306  pixel_ptr += 2;
307  for (col = 1; col < width; col++) {
308  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
309  uqvq -= AV_RL16(encoded+pixel_ptr+1);
310  AV_WL16(encoded+pixel_ptr+1, uqvq);
311  pixel_ptr += 3;
312  }
313  }
314  break;
315  case IMGTYPE_YUV422:
316  for (row = 0; row < height; row++) {
317  pixel_ptr = row * width * 2;
318  yq = uq = vq =0;
319  for (col = 0; col < width/4; col++) {
320  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
321  encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
322  encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
323  encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
324  encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
325  encoded[pixel_ptr+5] = uq -= encoded[pixel_ptr+5];
326  encoded[pixel_ptr+6] = vq -= encoded[pixel_ptr+6];
327  encoded[pixel_ptr+7] = vq -= encoded[pixel_ptr+7];
328  pixel_ptr += 8;
329  }
330  }
331  break;
332  case IMGTYPE_YUV411:
333  for (row = 0; row < height; row++) {
334  pixel_ptr = row * width / 2 * 3;
335  yq = uq = vq =0;
336  for (col = 0; col < width/4; col++) {
337  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
338  encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
339  encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
340  encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
341  encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
342  encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
343  pixel_ptr += 6;
344  }
345  }
346  break;
347  case IMGTYPE_YUV211:
348  for (row = 0; row < height; row++) {
349  pixel_ptr = row * width * 2;
350  yq = uq = vq =0;
351  for (col = 0; col < width/2; col++) {
352  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
353  encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
354  encoded[pixel_ptr+2] = uq -= encoded[pixel_ptr+2];
355  encoded[pixel_ptr+3] = vq -= encoded[pixel_ptr+3];
356  pixel_ptr += 4;
357  }
358  }
359  break;
360  case IMGTYPE_YUV420:
361  for (row = 0; row < height/2; row++) {
362  pixel_ptr = row * width * 3;
363  yq = y1q = uq = vq =0;
364  for (col = 0; col < width/2; col++) {
365  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
366  encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
367  encoded[pixel_ptr+2] = y1q -= encoded[pixel_ptr+2];
368  encoded[pixel_ptr+3] = y1q -= encoded[pixel_ptr+3];
369  encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
370  encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
371  pixel_ptr += 6;
372  }
373  }
374  break;
375  default:
376  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in pngfilter switch.\n");
377  return AVERROR_INVALIDDATA;
378  }
379  }
380 
381  /* Convert colorspace */
382  y_out = frame->data[0] + (height - 1) * frame->linesize[0];
383  u_out = frame->data[1] + (height - 1) * frame->linesize[1];
384  v_out = frame->data[2] + (height - 1) * frame->linesize[2];
385  switch (c->imgtype) {
386  case IMGTYPE_YUV111:
387  for (row = 0; row < height; row++) {
388  for (col = 0; col < width; col++) {
389  y_out[col] = *encoded++;
390  u_out[col] = *encoded++ + 128;
391  v_out[col] = *encoded++ + 128;
392  }
393  y_out -= frame->linesize[0];
394  u_out -= frame->linesize[1];
395  v_out -= frame->linesize[2];
396  }
397  break;
398  case IMGTYPE_YUV422:
399  for (row = 0; row < height; row++) {
400  for (col = 0; col < width - 3; col += 4) {
401  memcpy(y_out + col, encoded, 4);
402  encoded += 4;
403  u_out[ col >> 1 ] = *encoded++ + 128;
404  u_out[(col >> 1) + 1] = *encoded++ + 128;
405  v_out[ col >> 1 ] = *encoded++ + 128;
406  v_out[(col >> 1) + 1] = *encoded++ + 128;
407  }
408  y_out -= frame->linesize[0];
409  u_out -= frame->linesize[1];
410  v_out -= frame->linesize[2];
411  }
412  break;
413  case IMGTYPE_RGB24:
414  for (row = height - 1; row >= 0; row--) {
415  pixel_ptr = row * frame->linesize[0];
416  memcpy(outptr + pixel_ptr, encoded, 3 * width);
417  encoded += 3 * width;
418  }
419  break;
420  case IMGTYPE_YUV411:
421  for (row = 0; row < height; row++) {
422  for (col = 0; col < width - 3; col += 4) {
423  memcpy(y_out + col, encoded, 4);
424  encoded += 4;
425  u_out[col >> 2] = *encoded++ + 128;
426  v_out[col >> 2] = *encoded++ + 128;
427  }
428  y_out -= frame->linesize[0];
429  u_out -= frame->linesize[1];
430  v_out -= frame->linesize[2];
431  }
432  break;
433  case IMGTYPE_YUV211:
434  for (row = 0; row < height; row++) {
435  for (col = 0; col < width - 1; col += 2) {
436  memcpy(y_out + col, encoded, 2);
437  encoded += 2;
438  u_out[col >> 1] = *encoded++ + 128;
439  v_out[col >> 1] = *encoded++ + 128;
440  }
441  y_out -= frame->linesize[0];
442  u_out -= frame->linesize[1];
443  v_out -= frame->linesize[2];
444  }
445  break;
446  case IMGTYPE_YUV420:
447  u_out = frame->data[1] + ((height >> 1) - 1) * frame->linesize[1];
448  v_out = frame->data[2] + ((height >> 1) - 1) * frame->linesize[2];
449  for (row = 0; row < height - 1; row += 2) {
450  for (col = 0; col < width - 1; col += 2) {
451  memcpy(y_out + col, encoded, 2);
452  encoded += 2;
453  memcpy(y_out + col - frame->linesize[0], encoded, 2);
454  encoded += 2;
455  u_out[col >> 1] = *encoded++ + 128;
456  v_out[col >> 1] = *encoded++ + 128;
457  }
458  y_out -= frame->linesize[0] << 1;
459  u_out -= frame->linesize[1];
460  v_out -= frame->linesize[2];
461  }
462  break;
463  default:
464  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in image decoder.\n");
465  return AVERROR_INVALIDDATA;
466  }
467 
468  *got_frame = 1;
469 
470  /* always report that the buffer was completely consumed */
471  return buf_size;
472 }
473 
474 /*
475  *
476  * Init lcl decoder
477  *
478  */
479 static av_cold int decode_init(AVCodecContext *avctx)
480 {
481  LclDecContext * const c = avctx->priv_data;
482  unsigned int basesize = avctx->width * avctx->height;
483  unsigned int max_basesize = FFALIGN(avctx->width, 4) *
484  FFALIGN(avctx->height, 4);
485  unsigned int max_decomp_size;
486  int subsample_h, subsample_v;
487 
488  if (avctx->extradata_size < 8) {
489  av_log(avctx, AV_LOG_ERROR, "Extradata size too small.\n");
490  return AVERROR_INVALIDDATA;
491  }
492 
493  /* Check codec type */
494  if ((avctx->codec_id == AV_CODEC_ID_MSZH && avctx->extradata[7] != CODEC_MSZH) ||
495  (avctx->codec_id == AV_CODEC_ID_ZLIB && avctx->extradata[7] != CODEC_ZLIB)) {
496  av_log(avctx, AV_LOG_ERROR, "Codec id and codec type mismatch. This should not happen.\n");
497  }
498 
499  /* Detect image type */
500  switch (c->imgtype = avctx->extradata[4]) {
501  case IMGTYPE_YUV111:
502  c->decomp_size = basesize * 3;
503  max_decomp_size = max_basesize * 3;
504  avctx->pix_fmt = AV_PIX_FMT_YUV444P;
505  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 1:1:1.\n");
506  break;
507  case IMGTYPE_YUV422:
508  c->decomp_size = basesize * 2;
509  max_decomp_size = max_basesize * 2;
510  avctx->pix_fmt = AV_PIX_FMT_YUV422P;
511  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:2.\n");
512  if (avctx->width % 4) {
513  avpriv_request_sample(avctx, "Unsupported dimensions\n");
514  return AVERROR_INVALIDDATA;
515  }
516  break;
517  case IMGTYPE_RGB24:
518  c->decomp_size = basesize * 3;
519  max_decomp_size = max_basesize * 3;
520  avctx->pix_fmt = AV_PIX_FMT_BGR24;
521  av_log(avctx, AV_LOG_DEBUG, "Image type is RGB 24.\n");
522  break;
523  case IMGTYPE_YUV411:
524  c->decomp_size = basesize / 2 * 3;
525  max_decomp_size = max_basesize / 2 * 3;
526  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
527  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:1:1.\n");
528  break;
529  case IMGTYPE_YUV211:
530  c->decomp_size = basesize * 2;
531  max_decomp_size = max_basesize * 2;
532  avctx->pix_fmt = AV_PIX_FMT_YUV422P;
533  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 2:1:1.\n");
534  break;
535  case IMGTYPE_YUV420:
536  c->decomp_size = basesize / 2 * 3;
537  max_decomp_size = max_basesize / 2 * 3;
538  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
539  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:0.\n");
540  break;
541  default:
542  av_log(avctx, AV_LOG_ERROR, "Unsupported image format %d.\n", c->imgtype);
543  return AVERROR_INVALIDDATA;
544  }
545 
546  av_pix_fmt_get_chroma_sub_sample(avctx->pix_fmt, &subsample_h, &subsample_v);
547  if (avctx->width % (1<<subsample_h) || avctx->height % (1<<subsample_v)) {
548  avpriv_request_sample(avctx, "Unsupported dimensions\n");
549  return AVERROR_INVALIDDATA;
550  }
551 
552  /* Detect compression method */
553  c->compression = (int8_t)avctx->extradata[5];
554  switch (avctx->codec_id) {
555  case AV_CODEC_ID_MSZH:
556  switch (c->compression) {
557  case COMP_MSZH:
558  av_log(avctx, AV_LOG_DEBUG, "Compression enabled.\n");
559  break;
560  case COMP_MSZH_NOCOMP:
561  c->decomp_size = 0;
562  av_log(avctx, AV_LOG_DEBUG, "No compression.\n");
563  break;
564  default:
565  av_log(avctx, AV_LOG_ERROR, "Unsupported compression format for MSZH (%d).\n", c->compression);
566  return AVERROR_INVALIDDATA;
567  }
568  break;
569 #if CONFIG_ZLIB_DECODER
570  case AV_CODEC_ID_ZLIB:
571  switch (c->compression) {
572  case COMP_ZLIB_HISPEED:
573  av_log(avctx, AV_LOG_DEBUG, "High speed compression.\n");
574  break;
575  case COMP_ZLIB_HICOMP:
576  av_log(avctx, AV_LOG_DEBUG, "High compression.\n");
577  break;
578  case COMP_ZLIB_NORMAL:
579  av_log(avctx, AV_LOG_DEBUG, "Normal compression.\n");
580  break;
581  default:
582  if (c->compression < Z_NO_COMPRESSION || c->compression > Z_BEST_COMPRESSION) {
583  av_log(avctx, AV_LOG_ERROR, "Unsupported compression level for ZLIB: (%d).\n", c->compression);
584  return AVERROR_INVALIDDATA;
585  }
586  av_log(avctx, AV_LOG_DEBUG, "Compression level for ZLIB: (%d).\n", c->compression);
587  }
588  break;
589 #endif
590  default:
591  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in compression switch.\n");
592  return AVERROR_INVALIDDATA;
593  }
594 
595  /* Allocate decompression buffer */
596  if (c->decomp_size) {
597  if ((c->decomp_buf = av_malloc(max_decomp_size)) == NULL) {
598  av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
599  return AVERROR(ENOMEM);
600  }
601  }
602 
603  /* Detect flags */
604  c->flags = avctx->extradata[6];
605  if (c->flags & FLAG_MULTITHREAD)
606  av_log(avctx, AV_LOG_DEBUG, "Multithread encoder flag set.\n");
607  if (c->flags & FLAG_NULLFRAME)
608  av_log(avctx, AV_LOG_DEBUG, "Nullframe insertion flag set.\n");
609  if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER))
610  av_log(avctx, AV_LOG_DEBUG, "PNG filter flag set.\n");
611  if (c->flags & FLAGMASK_UNUSED)
612  av_log(avctx, AV_LOG_ERROR, "Unknown flag set (%d).\n", c->flags);
613 
614  /* If needed init zlib */
615 #if CONFIG_ZLIB_DECODER
616  if (avctx->codec_id == AV_CODEC_ID_ZLIB) {
617  int zret;
618  c->zstream.zalloc = Z_NULL;
619  c->zstream.zfree = Z_NULL;
620  c->zstream.opaque = Z_NULL;
621  zret = inflateInit(&c->zstream);
622  if (zret != Z_OK) {
623  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
624  av_freep(&c->decomp_buf);
625  return AVERROR_UNKNOWN;
626  }
627  }
628 #endif
629 
630  return 0;
631 }
632 
633 /*
634  *
635  * Uninit lcl decoder
636  *
637  */
638 static av_cold int decode_end(AVCodecContext *avctx)
639 {
640  LclDecContext * const c = avctx->priv_data;
641 
642  av_freep(&c->decomp_buf);
643 #if CONFIG_ZLIB_DECODER
644  if (avctx->codec_id == AV_CODEC_ID_ZLIB)
645  inflateEnd(&c->zstream);
646 #endif
647 
648  return 0;
649 }
650 
651 #if CONFIG_MSZH_DECODER
652 AVCodec ff_mszh_decoder = {
653  .name = "mszh",
654  .type = AVMEDIA_TYPE_VIDEO,
655  .id = AV_CODEC_ID_MSZH,
656  .priv_data_size = sizeof(LclDecContext),
657  .init = decode_init,
658  .close = decode_end,
659  .decode = decode_frame,
660  .capabilities = CODEC_CAP_DR1,
661  .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) MSZH"),
662 };
663 #endif
664 
665 #if CONFIG_ZLIB_DECODER
666 AVCodec ff_zlib_decoder = {
667  .name = "zlib",
668  .type = AVMEDIA_TYPE_VIDEO,
669  .id = AV_CODEC_ID_ZLIB,
670  .priv_data_size = sizeof(LclDecContext),
671  .init = decode_init,
672  .close = decode_end,
673  .decode = decode_frame,
674  .capabilities = CODEC_CAP_DR1,
675  .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
676 };
677 #endif
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