FFmpeg
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 #include <stdio.h>
41 #include <stdlib.h>
42 
43 #include "libavutil/mem.h"
44 #include "libavutil/pixdesc.h"
45 #include "avcodec.h"
46 #include "bytestream.h"
47 #include "internal.h"
48 #include "lcl.h"
49 #include "thread.h"
50 
51 #if CONFIG_ZLIB_DECODER
52 #include <zlib.h>
53 #endif
54 
55 typedef struct LclDecContext {
56  // Image type
57  int imgtype;
58  // Compression type
59  int compression;
60  // Flags
61  int flags;
62  // Decompressed data size
63  unsigned int decomp_size;
64  // Decompression buffer
65  unsigned char* decomp_buf;
66 #if CONFIG_ZLIB_DECODER
67  z_stream zstream;
68 #endif
69 } LclDecContext;
70 
71 
72 /**
73  * @param srcptr compressed source buffer, must be padded with at least 5 extra bytes
74  * @param destptr must be padded sufficiently for av_memcpy_backptr
75  */
76 static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsigned char * destptr, unsigned int destsize)
77 {
78  unsigned char *destptr_bak = destptr;
79  unsigned char *destptr_end = destptr + destsize;
80  const unsigned char *srcptr_end = srcptr + srclen;
81  unsigned mask = *srcptr++;
82  unsigned maskbit = 0x80;
83 
84  while (srcptr < srcptr_end && destptr < destptr_end) {
85  if (!(mask & maskbit)) {
86  memcpy(destptr, srcptr, 4);
87  destptr += 4;
88  srcptr += 4;
89  } else {
90  unsigned ofs = bytestream_get_le16(&srcptr);
91  unsigned cnt = (ofs >> 11) + 1;
92  ofs &= 0x7ff;
93  ofs = FFMIN(ofs, destptr - destptr_bak);
94  cnt *= 4;
95  cnt = FFMIN(cnt, destptr_end - destptr);
96  if (ofs) {
97  av_memcpy_backptr(destptr, ofs, cnt);
98  } else {
99  // Not known what the correct behaviour is, but
100  // this at least avoids uninitialized data.
101  memset(destptr, 0, cnt);
102  }
103  destptr += cnt;
104  }
105  maskbit >>= 1;
106  if (!maskbit) {
107  mask = *srcptr++;
108  while (!mask) {
109  if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;
110  memcpy(destptr, srcptr, 32);
111  destptr += 32;
112  srcptr += 32;
113  mask = *srcptr++;
114  }
115  maskbit = 0x80;
116  }
117  }
118 
119  return destptr - destptr_bak;
120 }
121 
122 
123 #if CONFIG_ZLIB_DECODER
124 /**
125  * @brief decompress a zlib-compressed data block into decomp_buf
126  * @param src compressed input buffer
127  * @param src_len data length in input buffer
128  * @param offset offset in decomp_buf
129  * @param expected expected decompressed length
130  */
131 static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)
132 {
133  LclDecContext *c = avctx->priv_data;
134  int zret = inflateReset(&c->zstream);
135  if (zret != Z_OK) {
136  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
137  return AVERROR_UNKNOWN;
138  }
139  c->zstream.next_in = src;
140  c->zstream.avail_in = src_len;
141  c->zstream.next_out = c->decomp_buf + offset;
142  c->zstream.avail_out = c->decomp_size - offset;
143  zret = inflate(&c->zstream, Z_FINISH);
144  if (zret != Z_OK && zret != Z_STREAM_END) {
145  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
146  return AVERROR_UNKNOWN;
147  }
148  if (expected != (unsigned int)c->zstream.total_out) {
149  av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %lu)\n",
150  expected, c->zstream.total_out);
151  return AVERROR_UNKNOWN;
152  }
153  return c->zstream.total_out;
154 }
155 #endif
156 
157 
158 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
159 {
160  AVFrame *frame = data;
161  ThreadFrame tframe = { .f = data };
162  const uint8_t *buf = avpkt->data;
163  int buf_size = avpkt->size;
164  LclDecContext * const c = avctx->priv_data;
165  unsigned int pixel_ptr;
166  int row, col;
167  unsigned char *encoded = avpkt->data, *outptr;
168  uint8_t *y_out, *u_out, *v_out;
169  unsigned int width = avctx->width; // Real image width
170  unsigned int height = avctx->height; // Real image height
171  unsigned int mszh_dlen;
172  unsigned char yq, y1q, uq, vq;
173  int uqvq, ret;
174  unsigned int mthread_inlen, mthread_outlen;
175  unsigned int len = buf_size;
176  int linesize, offset;
177 
178  if ((ret = ff_thread_get_buffer(avctx, &tframe, 0)) < 0)
179  return ret;
180 
181  outptr = frame->data[0]; // Output image pointer
182 
183  /* Decompress frame */
184  switch (avctx->codec_id) {
185  case AV_CODEC_ID_MSZH:
186  switch (c->compression) {
187  case COMP_MSZH:
188  if (c->imgtype == IMGTYPE_RGB24 && len == FFALIGN(width * 3, 4) * height ||
189  c->imgtype == IMGTYPE_YUV111 && len == width * height * 3) {
190  ;
191  } else if (c->flags & FLAG_MULTITHREAD) {
192  mthread_inlen = AV_RL32(buf);
193  if (len < 8 || len - 8 < mthread_inlen) {
194  av_log(avctx, AV_LOG_ERROR, "len %d is too small\n", len);
195  return AVERROR_INVALIDDATA;
196  }
197  mthread_outlen = AV_RL32(buf + 4);
198  mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
199  mszh_dlen = mszh_decomp(buf + 8, mthread_inlen, c->decomp_buf, c->decomp_size);
200  if (mthread_outlen != mszh_dlen) {
201  av_log(avctx, AV_LOG_ERROR, "Mthread1 decoded size differs (%d != %d)\n",
202  mthread_outlen, mszh_dlen);
203  return AVERROR_INVALIDDATA;
204  }
205  mszh_dlen = mszh_decomp(buf + 8 + mthread_inlen, len - 8 - mthread_inlen,
206  c->decomp_buf + mthread_outlen, c->decomp_size - mthread_outlen);
207  if (mthread_outlen != mszh_dlen) {
208  av_log(avctx, AV_LOG_ERROR, "Mthread2 decoded size differs (%d != %d)\n",
209  mthread_outlen, mszh_dlen);
210  return AVERROR_INVALIDDATA;
211  }
212  encoded = c->decomp_buf;
213  len = c->decomp_size;
214  } else {
215  mszh_dlen = mszh_decomp(buf, len, c->decomp_buf, c->decomp_size);
216  if (c->decomp_size != mszh_dlen) {
217  av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %d)\n",
218  c->decomp_size, mszh_dlen);
219  return AVERROR_INVALIDDATA;
220  }
221  encoded = c->decomp_buf;
222  len = mszh_dlen;
223  }
224  break;
225  case COMP_MSZH_NOCOMP: {
226  int bppx2;
227  switch (c->imgtype) {
228  case IMGTYPE_YUV111:
229  case IMGTYPE_RGB24:
230  bppx2 = 6;
231  break;
232  case IMGTYPE_YUV422:
233  case IMGTYPE_YUV211:
234  bppx2 = 4;
235  break;
236  case IMGTYPE_YUV411:
237  case IMGTYPE_YUV420:
238  bppx2 = 3;
239  break;
240  default:
241  bppx2 = 0; // will error out below
242  break;
243  }
244  if (len < ((width * height * bppx2) >> 1))
245  return AVERROR_INVALIDDATA;
246  break;
247  }
248  default:
249  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown MSZH compression in frame decoder.\n");
250  return AVERROR_INVALIDDATA;
251  }
252  break;
253 #if CONFIG_ZLIB_DECODER
254  case AV_CODEC_ID_ZLIB:
255  /* Using the original dll with normal compression (-1) and RGB format
256  * gives a file with ZLIB fourcc, but frame is really uncompressed.
257  * To be sure that's true check also frame size */
258  if (c->compression == COMP_ZLIB_NORMAL && c->imgtype == IMGTYPE_RGB24 &&
259  len == width * height * 3) {
260  if (c->flags & FLAG_PNGFILTER) {
261  memcpy(c->decomp_buf, buf, len);
262  encoded = c->decomp_buf;
263  } else {
264  break;
265  }
266  } else if (c->flags & FLAG_MULTITHREAD) {
267  mthread_inlen = AV_RL32(buf);
268  mthread_inlen = FFMIN(mthread_inlen, len - 8);
269  mthread_outlen = AV_RL32(buf + 4);
270  mthread_outlen = FFMIN(mthread_outlen, c->decomp_size);
271  ret = zlib_decomp(avctx, buf + 8, mthread_inlen, 0, mthread_outlen);
272  if (ret < 0) return ret;
273  ret = zlib_decomp(avctx, buf + 8 + mthread_inlen, len - 8 - mthread_inlen,
274  mthread_outlen, mthread_outlen);
275  if (ret < 0) return ret;
276  } else {
277  int ret = zlib_decomp(avctx, buf, len, 0, c->decomp_size);
278  if (ret < 0) return ret;
279  }
280  encoded = c->decomp_buf;
281  len = c->decomp_size;
282  break;
283 #endif
284  default:
285  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in frame decoder compression switch.\n");
286  return AVERROR_INVALIDDATA;
287  }
288 
289 
290  /* Apply PNG filter */
291  if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER)) {
292  switch (c->imgtype) {
293  case IMGTYPE_YUV111:
294  case IMGTYPE_RGB24:
295  for (row = 0; row < height; row++) {
296  pixel_ptr = row * width * 3;
297  yq = encoded[pixel_ptr++];
298  uqvq = AV_RL16(encoded+pixel_ptr);
299  pixel_ptr += 2;
300  for (col = 1; col < width; col++) {
301  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
302  uqvq -= AV_RL16(encoded+pixel_ptr+1);
303  AV_WL16(encoded+pixel_ptr+1, uqvq);
304  pixel_ptr += 3;
305  }
306  }
307  break;
308  case IMGTYPE_YUV422:
309  for (row = 0; row < height; row++) {
310  pixel_ptr = row * width * 2;
311  yq = uq = vq =0;
312  for (col = 0; col < width/4; col++) {
313  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
314  encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
315  encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
316  encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
317  encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
318  encoded[pixel_ptr+5] = uq -= encoded[pixel_ptr+5];
319  encoded[pixel_ptr+6] = vq -= encoded[pixel_ptr+6];
320  encoded[pixel_ptr+7] = vq -= encoded[pixel_ptr+7];
321  pixel_ptr += 8;
322  }
323  }
324  break;
325  case IMGTYPE_YUV411:
326  for (row = 0; row < height; row++) {
327  pixel_ptr = row * width / 2 * 3;
328  yq = uq = vq =0;
329  for (col = 0; col < width/4; col++) {
330  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
331  encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
332  encoded[pixel_ptr+2] = yq -= encoded[pixel_ptr+2];
333  encoded[pixel_ptr+3] = yq -= encoded[pixel_ptr+3];
334  encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
335  encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
336  pixel_ptr += 6;
337  }
338  }
339  break;
340  case IMGTYPE_YUV211:
341  for (row = 0; row < height; row++) {
342  pixel_ptr = row * width * 2;
343  yq = uq = vq =0;
344  for (col = 0; col < width/2; col++) {
345  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
346  encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
347  encoded[pixel_ptr+2] = uq -= encoded[pixel_ptr+2];
348  encoded[pixel_ptr+3] = vq -= encoded[pixel_ptr+3];
349  pixel_ptr += 4;
350  }
351  }
352  break;
353  case IMGTYPE_YUV420:
354  for (row = 0; row < height/2; row++) {
355  pixel_ptr = row * width * 3;
356  yq = y1q = uq = vq =0;
357  for (col = 0; col < width/2; col++) {
358  encoded[pixel_ptr] = yq -= encoded[pixel_ptr];
359  encoded[pixel_ptr+1] = yq -= encoded[pixel_ptr+1];
360  encoded[pixel_ptr+2] = y1q -= encoded[pixel_ptr+2];
361  encoded[pixel_ptr+3] = y1q -= encoded[pixel_ptr+3];
362  encoded[pixel_ptr+4] = uq -= encoded[pixel_ptr+4];
363  encoded[pixel_ptr+5] = vq -= encoded[pixel_ptr+5];
364  pixel_ptr += 6;
365  }
366  }
367  break;
368  default:
369  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in pngfilter switch.\n");
370  return AVERROR_INVALIDDATA;
371  }
372  }
373 
374  /* Convert colorspace */
375  y_out = frame->data[0] + (height - 1) * frame->linesize[0];
376  offset = (height - 1) * frame->linesize[1];
377  u_out = FF_PTR_ADD(frame->data[1], offset);
378  offset = (height - 1) * frame->linesize[2];
379  v_out = FF_PTR_ADD(frame->data[2], offset);
380  switch (c->imgtype) {
381  case IMGTYPE_YUV111:
382  for (row = 0; row < height; row++) {
383  for (col = 0; col < width; col++) {
384  y_out[col] = *encoded++;
385  u_out[col] = *encoded++ + 128;
386  v_out[col] = *encoded++ + 128;
387  }
388  y_out -= frame->linesize[0];
389  u_out -= frame->linesize[1];
390  v_out -= frame->linesize[2];
391  }
392  break;
393  case IMGTYPE_YUV422:
394  for (row = 0; row < height; row++) {
395  for (col = 0; col < width - 3; col += 4) {
396  memcpy(y_out + col, encoded, 4);
397  encoded += 4;
398  u_out[ col >> 1 ] = *encoded++ + 128;
399  u_out[(col >> 1) + 1] = *encoded++ + 128;
400  v_out[ col >> 1 ] = *encoded++ + 128;
401  v_out[(col >> 1) + 1] = *encoded++ + 128;
402  }
403  y_out -= frame->linesize[0];
404  u_out -= frame->linesize[1];
405  v_out -= frame->linesize[2];
406  }
407  break;
408  case IMGTYPE_RGB24:
409  linesize = len < FFALIGN(3 * width, 4) * height ? 3 * width : FFALIGN(3 * width, 4);
410  for (row = height - 1; row >= 0; row--) {
411  pixel_ptr = row * frame->linesize[0];
412  memcpy(outptr + pixel_ptr, encoded, 3 * width);
413  encoded += linesize;
414  }
415  break;
416  case IMGTYPE_YUV411:
417  for (row = 0; row < height; row++) {
418  for (col = 0; col < width - 3; col += 4) {
419  memcpy(y_out + col, encoded, 4);
420  encoded += 4;
421  u_out[col >> 2] = *encoded++ + 128;
422  v_out[col >> 2] = *encoded++ + 128;
423  }
424  y_out -= frame->linesize[0];
425  u_out -= frame->linesize[1];
426  v_out -= frame->linesize[2];
427  }
428  break;
429  case IMGTYPE_YUV211:
430  for (row = 0; row < height; row++) {
431  for (col = 0; col < width - 1; col += 2) {
432  memcpy(y_out + col, encoded, 2);
433  encoded += 2;
434  u_out[col >> 1] = *encoded++ + 128;
435  v_out[col >> 1] = *encoded++ + 128;
436  }
437  y_out -= frame->linesize[0];
438  u_out -= frame->linesize[1];
439  v_out -= frame->linesize[2];
440  }
441  break;
442  case IMGTYPE_YUV420:
443  u_out = frame->data[1] + ((height >> 1) - 1) * frame->linesize[1];
444  v_out = frame->data[2] + ((height >> 1) - 1) * frame->linesize[2];
445  for (row = 0; row < height - 1; row += 2) {
446  for (col = 0; col < width - 1; col += 2) {
447  memcpy(y_out + col, encoded, 2);
448  encoded += 2;
449  memcpy(y_out + col - frame->linesize[0], encoded, 2);
450  encoded += 2;
451  u_out[col >> 1] = *encoded++ + 128;
452  v_out[col >> 1] = *encoded++ + 128;
453  }
454  y_out -= frame->linesize[0] << 1;
455  u_out -= frame->linesize[1];
456  v_out -= frame->linesize[2];
457  }
458  break;
459  default:
460  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown imagetype in image decoder.\n");
461  return AVERROR_INVALIDDATA;
462  }
463 
464  frame->key_frame = 1;
465  frame->pict_type = AV_PICTURE_TYPE_I;
466 
467  *got_frame = 1;
468 
469  /* always report that the buffer was completely consumed */
470  return buf_size;
471 }
472 
473 static av_cold int decode_init(AVCodecContext *avctx)
474 {
475  LclDecContext * const c = avctx->priv_data;
476  unsigned int basesize = avctx->width * avctx->height;
477  unsigned int max_basesize = FFALIGN(avctx->width, 4) *
478  FFALIGN(avctx->height, 4);
479  unsigned int max_decomp_size;
480  int subsample_h, subsample_v;
481 
482  if (avctx->extradata_size < 8) {
483  av_log(avctx, AV_LOG_ERROR, "Extradata size too small.\n");
484  return AVERROR_INVALIDDATA;
485  }
486 
487  /* Check codec type */
488  if ((avctx->codec_id == AV_CODEC_ID_MSZH && avctx->extradata[7] != CODEC_MSZH) ||
489  (avctx->codec_id == AV_CODEC_ID_ZLIB && avctx->extradata[7] != CODEC_ZLIB)) {
490  av_log(avctx, AV_LOG_ERROR, "Codec id and codec type mismatch. This should not happen.\n");
491  }
492 
493  /* Detect image type */
494  switch (c->imgtype = avctx->extradata[4]) {
495  case IMGTYPE_YUV111:
496  c->decomp_size = basesize * 3;
497  max_decomp_size = max_basesize * 3;
498  avctx->pix_fmt = AV_PIX_FMT_YUV444P;
499  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 1:1:1.\n");
500  break;
501  case IMGTYPE_YUV422:
502  c->decomp_size = basesize * 2;
503  max_decomp_size = max_basesize * 2;
504  avctx->pix_fmt = AV_PIX_FMT_YUV422P;
505  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:2.\n");
506  if (avctx->width % 4) {
507  avpriv_request_sample(avctx, "Unsupported dimensions");
508  return AVERROR_INVALIDDATA;
509  }
510  break;
511  case IMGTYPE_RGB24:
512  c->decomp_size = basesize * 3;
513  max_decomp_size = max_basesize * 3;
514  avctx->pix_fmt = AV_PIX_FMT_BGR24;
515  av_log(avctx, AV_LOG_DEBUG, "Image type is RGB 24.\n");
516  break;
517  case IMGTYPE_YUV411:
518  c->decomp_size = basesize / 2 * 3;
519  max_decomp_size = max_basesize / 2 * 3;
520  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
521  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:1:1.\n");
522  break;
523  case IMGTYPE_YUV211:
524  c->decomp_size = basesize * 2;
525  max_decomp_size = max_basesize * 2;
526  avctx->pix_fmt = AV_PIX_FMT_YUV422P;
527  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 2:1:1.\n");
528  break;
529  case IMGTYPE_YUV420:
530  c->decomp_size = basesize / 2 * 3;
531  max_decomp_size = max_basesize / 2 * 3;
532  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
533  av_log(avctx, AV_LOG_DEBUG, "Image type is YUV 4:2:0.\n");
534  break;
535  default:
536  av_log(avctx, AV_LOG_ERROR, "Unsupported image format %d.\n", c->imgtype);
537  return AVERROR_INVALIDDATA;
538  }
539 
540  av_pix_fmt_get_chroma_sub_sample(avctx->pix_fmt, &subsample_h, &subsample_v);
541  if (avctx->width % (1<<subsample_h) || avctx->height % (1<<subsample_v)) {
542  avpriv_request_sample(avctx, "Unsupported dimensions");
543  return AVERROR_INVALIDDATA;
544  }
545 
546  /* Detect compression method */
547  c->compression = (int8_t)avctx->extradata[5];
548  switch (avctx->codec_id) {
549  case AV_CODEC_ID_MSZH:
550  switch (c->compression) {
551  case COMP_MSZH:
552  av_log(avctx, AV_LOG_DEBUG, "Compression enabled.\n");
553  break;
554  case COMP_MSZH_NOCOMP:
555  c->decomp_size = 0;
556  av_log(avctx, AV_LOG_DEBUG, "No compression.\n");
557  break;
558  default:
559  av_log(avctx, AV_LOG_ERROR, "Unsupported compression format for MSZH (%d).\n", c->compression);
560  return AVERROR_INVALIDDATA;
561  }
562  break;
563 #if CONFIG_ZLIB_DECODER
564  case AV_CODEC_ID_ZLIB:
565  switch (c->compression) {
566  case COMP_ZLIB_HISPEED:
567  av_log(avctx, AV_LOG_DEBUG, "High speed compression.\n");
568  break;
569  case COMP_ZLIB_HICOMP:
570  av_log(avctx, AV_LOG_DEBUG, "High compression.\n");
571  break;
572  case COMP_ZLIB_NORMAL:
573  av_log(avctx, AV_LOG_DEBUG, "Normal compression.\n");
574  break;
575  default:
576  if (c->compression < Z_NO_COMPRESSION || c->compression > Z_BEST_COMPRESSION) {
577  av_log(avctx, AV_LOG_ERROR, "Unsupported compression level for ZLIB: (%d).\n", c->compression);
578  return AVERROR_INVALIDDATA;
579  }
580  av_log(avctx, AV_LOG_DEBUG, "Compression level for ZLIB: (%d).\n", c->compression);
581  }
582  break;
583 #endif
584  default:
585  av_log(avctx, AV_LOG_ERROR, "BUG! Unknown codec in compression switch.\n");
586  return AVERROR_INVALIDDATA;
587  }
588 
589  /* Allocate decompression buffer */
590  if (c->decomp_size) {
591  if (!(c->decomp_buf = av_malloc(max_decomp_size))) {
592  av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
593  return AVERROR(ENOMEM);
594  }
595  }
596 
597  /* Detect flags */
598  c->flags = avctx->extradata[6];
599  if (c->flags & FLAG_MULTITHREAD)
600  av_log(avctx, AV_LOG_DEBUG, "Multithread encoder flag set.\n");
601  if (c->flags & FLAG_NULLFRAME)
602  av_log(avctx, AV_LOG_DEBUG, "Nullframe insertion flag set.\n");
603  if (avctx->codec_id == AV_CODEC_ID_ZLIB && (c->flags & FLAG_PNGFILTER))
604  av_log(avctx, AV_LOG_DEBUG, "PNG filter flag set.\n");
605  if (c->flags & FLAGMASK_UNUSED)
606  av_log(avctx, AV_LOG_ERROR, "Unknown flag set (%d).\n", c->flags);
607 
608  /* If needed init zlib */
609 #if CONFIG_ZLIB_DECODER
610  if (avctx->codec_id == AV_CODEC_ID_ZLIB) {
611  int zret;
612  c->zstream.zalloc = Z_NULL;
613  c->zstream.zfree = Z_NULL;
614  c->zstream.opaque = Z_NULL;
615  zret = inflateInit(&c->zstream);
616  if (zret != Z_OK) {
617  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
618  av_freep(&c->decomp_buf);
619  return AVERROR_UNKNOWN;
620  }
621  }
622 #endif
623 
624  return 0;
625 }
626 
627 static av_cold int decode_end(AVCodecContext *avctx)
628 {
629  LclDecContext * const c = avctx->priv_data;
630 
631  av_freep(&c->decomp_buf);
632 #if CONFIG_ZLIB_DECODER
633  if (avctx->codec_id == AV_CODEC_ID_ZLIB)
634  inflateEnd(&c->zstream);
635 #endif
636 
637  return 0;
638 }
639 
640 #if CONFIG_MSZH_DECODER
641 const AVCodec ff_mszh_decoder = {
642  .name = "mszh",
643  .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) MSZH"),
644  .type = AVMEDIA_TYPE_VIDEO,
645  .id = AV_CODEC_ID_MSZH,
646  .priv_data_size = sizeof(LclDecContext),
647  .init = decode_init,
648  .close = decode_end,
649  .decode = decode_frame,
650  .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
651  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
652 };
653 #endif
654 
655 #if CONFIG_ZLIB_DECODER
656 const AVCodec ff_zlib_decoder = {
657  .name = "zlib",
658  .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"),
659  .type = AVMEDIA_TYPE_VIDEO,
660  .id = AV_CODEC_ID_ZLIB,
661  .priv_data_size = sizeof(LclDecContext),
662  .init = decode_init,
663  .close = decode_end,
664  .decode = decode_frame,
665  .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
666  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
667 };
668 #endif
LclDecContext::decomp_size
unsigned int decomp_size
Definition: lcldec.c:63
AVCodec
AVCodec.
Definition: codec.h:202
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:42
ff_zlib_decoder
const AVCodec ff_zlib_decoder
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
IMGTYPE_YUV420
#define IMGTYPE_YUV420
Definition: lcl.h:33
CODEC_ZLIB
#define CODEC_ZLIB
Definition: lcl.h:47
mszh_decomp
static unsigned int mszh_decomp(const unsigned char *srcptr, int srclen, unsigned char *destptr, unsigned int destsize)
Definition: lcldec.c:76
IMGTYPE_YUV211
#define IMGTYPE_YUV211
Definition: lcl.h:32
COMP_MSZH_NOCOMP
#define COMP_MSZH_NOCOMP
Definition: lcl.h:36
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:317
pixdesc.h
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:373
data
const char data[16]
Definition: mxf.c:143
FLAG_MULTITHREAD
#define FLAG_MULTITHREAD
Definition: lcl.h:41
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
ff_mszh_decoder
const AVCodec ff_mszh_decoder
AVERROR_UNKNOWN
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:73
thread.h
ThreadFrame::f
AVFrame * f
Definition: thread.h:35
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
lcl.h
init
static int init
Definition: av_tx.c:47
LclDecContext::flags
int flags
Definition: lcldec.c:61
inflate
static void inflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord, int maxc)
Definition: vf_neighbor.c:193
AV_CODEC_ID_MSZH
@ AV_CODEC_ID_MSZH
Definition: codec_id.h:103
ff_thread_get_buffer
the pkt_dts and pkt_pts fields in AVFrame will work as usual Restrictions on codec whose streams don t reset across will not work because their bitstreams cannot be decoded in parallel *The contents of buffers must not be read before as well as code calling up to before the decode process starts Call have so the codec calls ff_thread_report set FF_CODEC_CAP_ALLOCATE_PROGRESS in AVCodec caps_internal and use ff_thread_get_buffer() to allocate frames. The frames must then be freed with ff_thread_release_buffer(). Otherwise decode directly into the user-supplied frames. Call ff_thread_report_progress() after some part of the current picture has decoded. A good place to put this is where draw_horiz_band() is called - add this if it isn 't called anywhere
av_pix_fmt_get_chroma_sub_sample
int av_pix_fmt_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift)
Utility function to access log2_chroma_w log2_chroma_h from the pixel format AVPixFmtDescriptor.
Definition: pixdesc.c:2688
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
mask
static const uint16_t mask[17]
Definition: lzw.c:38
COMP_ZLIB_NORMAL
#define COMP_ZLIB_NORMAL
Definition: lcl.h:39
av_memcpy_backptr
void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
Overlapping memcpy() implementation.
Definition: mem.c:454
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
LclDecContext::imgtype
int imgtype
Definition: lcldec.c:57
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:485
width
#define width
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: lcldec.c:473
LclDecContext::decomp_buf
unsigned char * decomp_buf
Definition: lcldec.c:65
IMGTYPE_RGB24
#define IMGTYPE_RGB24
Definition: lcl.h:30
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:201
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
IMGTYPE_YUV422
#define IMGTYPE_YUV422
Definition: lcl.h:29
AV_PIX_FMT_YUV420P
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:393
AV_CODEC_CAP_FRAME_THREADS
#define AV_CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: codec.h:113
FLAG_NULLFRAME
#define FLAG_NULLFRAME
Definition: lcl.h:42
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
src
#define src
Definition: vp8dsp.c:255
AV_CODEC_ID_ZLIB
@ AV_CODEC_ID_ZLIB
Definition: codec_id.h:104
FF_PTR_ADD
#define FF_PTR_ADD(ptr, off)
Definition: internal.h:100
COMP_MSZH
#define COMP_MSZH
Definition: lcl.h:35
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
decode_end
static av_cold int decode_end(AVCodecContext *avctx)
Definition: lcldec.c:627
CODEC_MSZH
#define CODEC_MSZH
Definition: lcl.h:46
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:374
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
IMGTYPE_YUV411
#define IMGTYPE_YUV411
Definition: lcl.h:31
AV_WL16
#define AV_WL16(p, v)
Definition: intreadwrite.h:412
height
#define height
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
IMGTYPE_YUV111
#define IMGTYPE_YUV111
Definition: lcl.h:28
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:484
LclDecContext::compression
int compression
Definition: lcldec.c:59
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
COMP_ZLIB_HICOMP
#define COMP_ZLIB_HICOMP
Definition: lcl.h:38
COMP_ZLIB_HISPEED
#define COMP_ZLIB_HISPEED
Definition: lcl.h:37
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
len
int len
Definition: vorbis_enc_data.h:426
LclDecContext
Definition: lcldec.c:55
AVCodecContext::height
int height
Definition: avcodec.h:556
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:593
avcodec.h
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
AVCodecContext
main external API structure.
Definition: avcodec.h:383
ThreadFrame
Definition: thread.h:34
AV_PIX_FMT_YUV444P
@ AV_PIX_FMT_YUV444P
planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
Definition: pixfmt.h:71
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AV_PIX_FMT_YUV422P
@ AV_PIX_FMT_YUV422P
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:70
mem.h
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:37
FFALIGN
#define FFALIGN(x, a)
Definition: macros.h:78
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:410
FLAG_PNGFILTER
#define FLAG_PNGFILTER
Definition: lcl.h:43
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
AV_PIX_FMT_YUV411P
@ AV_PIX_FMT_YUV411P
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:73
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:556
bytestream.h
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
FLAGMASK_UNUSED
#define FLAGMASK_UNUSED
Definition: lcl.h:44
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
decode_frame
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: lcldec.c:158
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