FFmpeg  1.2.12
swfdec.c
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1 /*
2  * Flash Compatible Streaming Format demuxer
3  * Copyright (c) 2000 Fabrice Bellard
4  * Copyright (c) 2003 Tinic Uro
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 #include "libavutil/avassert.h"
24 #include "libavutil/channel_layout.h"
25 #include "libavutil/imgutils.h"
26 #include "libavutil/intreadwrite.h"
27 #include "swf.h"
28 
29 static const AVCodecTag swf_audio_codec_tags[] = {
30  { AV_CODEC_ID_PCM_S16LE, 0x00 },
31  { AV_CODEC_ID_ADPCM_SWF, 0x01 },
32  { AV_CODEC_ID_MP3, 0x02 },
33  { AV_CODEC_ID_PCM_S16LE, 0x03 },
34 // { AV_CODEC_ID_NELLYMOSER, 0x06 },
35  { AV_CODEC_ID_NONE, 0 },
36 };
37 
38 static int get_swf_tag(AVIOContext *pb, int *len_ptr)
39 {
40  int tag, len;
41 
42  if (url_feof(pb))
43  return AVERROR_EOF;
44 
45  tag = avio_rl16(pb);
46  len = tag & 0x3f;
47  tag = tag >> 6;
48  if (len == 0x3f) {
49  len = avio_rl32(pb);
50  }
51  *len_ptr = len;
52  return tag;
53 }
54 
55 
56 static int swf_probe(AVProbeData *p)
57 {
58  /* check file header */
59  if ((p->buf[0] == 'F' || p->buf[0] == 'C') && p->buf[1] == 'W' &&
60  p->buf[2] == 'S')
61  return AVPROBE_SCORE_MAX;
62  else
63  return 0;
64 }
65 
66 #if CONFIG_ZLIB
67 static int zlib_refill(void *opaque, uint8_t *buf, int buf_size)
68 {
69  AVFormatContext *s = opaque;
70  SWFContext *swf = s->priv_data;
71  z_stream *z = &swf->zstream;
72  int ret;
73 
74 retry:
75  if (!z->avail_in) {
76  int n = avio_read(s->pb, swf->zbuf_in, ZBUF_SIZE);
77  if (n < 0)
78  return n;
79  z->next_in = swf->zbuf_in;
80  z->avail_in = n;
81  }
82 
83  z->next_out = buf;
84  z->avail_out = buf_size;
85 
86  ret = inflate(z, Z_NO_FLUSH);
87  if (ret < 0)
88  return AVERROR(EINVAL);
89  if (ret == Z_STREAM_END)
90  return AVERROR_EOF;
91 
92  if (buf_size - z->avail_out == 0)
93  goto retry;
94 
95  return buf_size - z->avail_out;
96 }
97 #endif
98 
100 {
101  SWFContext *swf = s->priv_data;
102  AVIOContext *pb = s->pb;
103  int nbits, len, tag;
104 
105  tag = avio_rb32(pb) & 0xffffff00;
106  avio_rl32(pb);
107 
108  if (tag == MKBETAG('C', 'W', 'S', 0)) {
109  av_log(s, AV_LOG_INFO, "SWF compressed file detected\n");
110 #if CONFIG_ZLIB
111  swf->zbuf_in = av_malloc(ZBUF_SIZE);
112  swf->zbuf_out = av_malloc(ZBUF_SIZE);
113  swf->zpb = avio_alloc_context(swf->zbuf_out, ZBUF_SIZE, 0, s,
114  zlib_refill, NULL, NULL);
115  if (!swf->zbuf_in || !swf->zbuf_out || !swf->zpb)
116  return AVERROR(ENOMEM);
117  swf->zpb->seekable = 0;
118  if (inflateInit(&swf->zstream) != Z_OK) {
119  av_log(s, AV_LOG_ERROR, "Unable to init zlib context\n");
120  return AVERROR(EINVAL);
121  }
122  pb = swf->zpb;
123 #else
124  av_log(s, AV_LOG_ERROR, "zlib support is required to read SWF compressed files\n");
125  return AVERROR(EIO);
126 #endif
127  } else if (tag != MKBETAG('F', 'W', 'S', 0))
128  return AVERROR(EIO);
129  /* skip rectangle size */
130  nbits = avio_r8(pb) >> 3;
131  len = (4 * nbits - 3 + 7) / 8;
132  avio_skip(pb, len);
133  swf->frame_rate = avio_rl16(pb); /* 8.8 fixed */
134  avio_rl16(pb); /* frame count */
135 
136  swf->samples_per_frame = 0;
138  return 0;
139 }
140 
141 static AVStream *create_new_audio_stream(AVFormatContext *s, int id, int info)
142 {
143  int sample_rate_code, sample_size_code;
144  AVStream *ast = avformat_new_stream(s, NULL);
145  if (!ast)
146  return NULL;
147  ast->id = id;
148  if (info & 1) {
149  ast->codec->channels = 2;
151  } else {
152  ast->codec->channels = 1;
154  }
156  ast->codec->codec_id = ff_codec_get_id(swf_audio_codec_tags, info>>4 & 15);
158  sample_rate_code = info>>2 & 3;
159  sample_size_code = info>>1 & 1;
160  if (!sample_size_code && ast->codec->codec_id == AV_CODEC_ID_PCM_S16LE)
162  ast->codec->sample_rate = 44100 >> (3 - sample_rate_code);
163  avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
164  return ast;
165 }
166 
168 {
169  SWFContext *swf = s->priv_data;
170  AVIOContext *pb = s->pb;
171  AVStream *vst = NULL, *ast = NULL, *st = 0;
172  int tag, len, i, frame, v, res;
173 
174 #if CONFIG_ZLIB
175  if (swf->zpb)
176  pb = swf->zpb;
177 #endif
178 
179  for(;;) {
180  uint64_t pos = avio_tell(pb);
181  tag = get_swf_tag(pb, &len);
182  if (tag < 0)
183  return tag;
184  if (len < 0) {
185  av_log(s, AV_LOG_ERROR, "invalid tag length: %d\n", len);
186  return AVERROR_INVALIDDATA;
187  }
188  if (tag == TAG_VIDEOSTREAM) {
189  int ch_id = avio_rl16(pb);
190  len -= 2;
191 
192  for (i=0; i<s->nb_streams; i++) {
193  st = s->streams[i];
194  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->id == ch_id)
195  goto skip;
196  }
197 
198  avio_rl16(pb);
199  avio_rl16(pb);
200  avio_rl16(pb);
201  avio_r8(pb);
202  /* Check for FLV1 */
203  vst = avformat_new_stream(s, NULL);
204  if (!vst)
205  return AVERROR(ENOMEM);
206  vst->id = ch_id;
209  avpriv_set_pts_info(vst, 16, 256, swf->frame_rate);
210  len -= 8;
211  } else if (tag == TAG_STREAMHEAD || tag == TAG_STREAMHEAD2) {
212  /* streaming found */
213 
214  for (i=0; i<s->nb_streams; i++) {
215  st = s->streams[i];
216  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1)
217  goto skip;
218  }
219 
220  avio_r8(pb);
221  v = avio_r8(pb);
222  swf->samples_per_frame = avio_rl16(pb);
223  ast = create_new_audio_stream(s, -1, v); /* -1 to avoid clash with video stream ch_id */
224  if (!ast)
225  return AVERROR(ENOMEM);
226  len -= 4;
227  } else if (tag == TAG_DEFINESOUND) {
228  /* audio stream */
229  int ch_id = avio_rl16(pb);
230 
231  for (i=0; i<s->nb_streams; i++) {
232  st = s->streams[i];
233  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == ch_id)
234  goto skip;
235  }
236 
237  // FIXME: The entire audio stream is stored in a single chunk/tag. Normally,
238  // these are smaller audio streams in DEFINESOUND tags, but it's technically
239  // possible they could be huge. Break it up into multiple packets if it's big.
240  v = avio_r8(pb);
241  ast = create_new_audio_stream(s, ch_id, v);
242  if (!ast)
243  return AVERROR(ENOMEM);
244  ast->duration = avio_rl32(pb); // number of samples
245  if (((v>>4) & 15) == 2) { // MP3 sound data record
246  ast->skip_samples = avio_rl16(pb);
247  len -= 2;
248  }
249  len -= 7;
250  if ((res = av_get_packet(pb, pkt, len)) < 0)
251  return res;
252  pkt->pos = pos;
253  pkt->stream_index = ast->index;
254  return pkt->size;
255  } else if (tag == TAG_VIDEOFRAME) {
256  int ch_id = avio_rl16(pb);
257  len -= 2;
258  for(i=0; i<s->nb_streams; i++) {
259  st = s->streams[i];
260  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->id == ch_id) {
261  frame = avio_rl16(pb);
262  len -= 2;
263  if (len <= 0)
264  goto skip;
265  if ((res = av_get_packet(pb, pkt, len)) < 0)
266  return res;
267  pkt->pos = pos;
268  pkt->pts = frame;
269  pkt->stream_index = st->index;
270  return pkt->size;
271  }
272  }
273  } else if (tag == TAG_DEFINEBITSLOSSLESS || tag == TAG_DEFINEBITSLOSSLESS2) {
274 #if CONFIG_ZLIB
275  long out_len;
276  uint8_t *buf = NULL, *zbuf = NULL, *pal;
277  uint32_t colormap[AVPALETTE_COUNT] = {0};
278  const int alpha_bmp = tag == TAG_DEFINEBITSLOSSLESS2;
279  const int colormapbpp = 3 + alpha_bmp;
280  int linesize, colormapsize = 0;
281 
282  const int ch_id = avio_rl16(pb);
283  const int bmp_fmt = avio_r8(pb);
284  const int width = avio_rl16(pb);
285  const int height = avio_rl16(pb);
286  int pix_fmt;
287 
288  len -= 2+1+2+2;
289 
290  switch (bmp_fmt) {
291  case 3: // PAL-8
292  linesize = width;
293  colormapsize = avio_r8(pb) + 1;
294  len--;
295  break;
296  case 4: // RGB15
297  linesize = width * 2;
298  break;
299  case 5: // RGB24 (0RGB)
300  linesize = width * 4;
301  break;
302  default:
303  av_log(s, AV_LOG_ERROR, "invalid bitmap format %d, skipped\n", bmp_fmt);
304  goto bitmap_end_skip;
305  }
306 
307  linesize = FFALIGN(linesize, 4);
308 
309  if (av_image_check_size(width, height, 0, s) < 0 ||
310  linesize >= INT_MAX / height ||
311  linesize * height >= INT_MAX - colormapsize * colormapbpp) {
312  av_log(s, AV_LOG_ERROR, "invalid frame size %dx%d\n", width, height);
313  goto bitmap_end_skip;
314  }
315 
316  out_len = colormapsize * colormapbpp + linesize * height;
317 
318  av_dlog(s, "bitmap: ch=%d fmt=%d %dx%d (linesize=%d) len=%d->%ld pal=%d\n",
319  ch_id, bmp_fmt, width, height, linesize, len, out_len, colormapsize);
320 
321  zbuf = av_malloc(len);
322  buf = av_malloc(out_len);
323  if (!zbuf || !buf) {
324  res = AVERROR(ENOMEM);
325  goto bitmap_end;
326  }
327 
328  len = avio_read(pb, zbuf, len);
329  if (len < 0 || (res = uncompress(buf, &out_len, zbuf, len)) != Z_OK) {
330  av_log(s, AV_LOG_WARNING, "Failed to uncompress one bitmap\n");
331  goto bitmap_end_skip;
332  }
333 
334  for (i = 0; i < s->nb_streams; i++) {
335  st = s->streams[i];
336  if (st->codec->codec_id == AV_CODEC_ID_RAWVIDEO && st->id == -3)
337  break;
338  }
339  if (i == s->nb_streams) {
340  vst = avformat_new_stream(s, NULL);
341  if (!vst) {
342  res = AVERROR(ENOMEM);
343  goto bitmap_end;
344  }
345  vst->id = -3; /* -3 to avoid clash with video stream and audio stream */
348  avpriv_set_pts_info(vst, 64, 256, swf->frame_rate);
349  st = vst;
350  }
351 
352  if ((res = av_new_packet(pkt, out_len - colormapsize * colormapbpp)) < 0)
353  goto bitmap_end;
354  if (!st->codec->width && !st->codec->height) {
355  st->codec->width = width;
356  st->codec->height = height;
357  } else {
358  ff_add_param_change(pkt, 0, 0, 0, width, height);
359  }
360  pkt->pos = pos;
361  pkt->stream_index = st->index;
362 
363  switch (bmp_fmt) {
364  case 3:
365  pix_fmt = AV_PIX_FMT_PAL8;
366  for (i = 0; i < colormapsize; i++)
367  if (alpha_bmp) colormap[i] = buf[3]<<24 | AV_RB24(buf + 4*i);
368  else colormap[i] = 0xffU <<24 | AV_RB24(buf + 3*i);
370  if (!pal) {
371  res = AVERROR(ENOMEM);
372  goto bitmap_end;
373  }
374  memcpy(pal, colormap, AVPALETTE_SIZE);
375  break;
376  case 4:
377  pix_fmt = AV_PIX_FMT_RGB555;
378  break;
379  case 5:
380  pix_fmt = alpha_bmp ? AV_PIX_FMT_ARGB : AV_PIX_FMT_0RGB;
381  break;
382  default:
383  av_assert0(0);
384  }
385  if (st->codec->pix_fmt != AV_PIX_FMT_NONE && st->codec->pix_fmt != pix_fmt) {
386  av_log(s, AV_LOG_ERROR, "pixel format change unsupported\n");
387  res = AVERROR_PATCHWELCOME;
388  goto bitmap_end;
389  }
390  st->codec->pix_fmt = pix_fmt;
391 
392  if (linesize * height > pkt->size) {
393  res = AVERROR_INVALIDDATA;
394  goto bitmap_end;
395  }
396  memcpy(pkt->data, buf + colormapsize*colormapbpp, linesize * height);
397 
398  res = pkt->size;
399 
400 bitmap_end:
401  av_freep(&zbuf);
402  av_freep(&buf);
403  return res;
404 bitmap_end_skip:
405  av_freep(&zbuf);
406  av_freep(&buf);
407 #else
408  av_log(s, AV_LOG_ERROR, "this file requires zlib support compiled in\n");
409 #endif
410  } else if (tag == TAG_STREAMBLOCK) {
411  for (i = 0; i < s->nb_streams; i++) {
412  st = s->streams[i];
413  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1) {
414  if (st->codec->codec_id == AV_CODEC_ID_MP3) {
415  avio_skip(pb, 4);
416  len -= 4;
417  if (len <= 0)
418  goto skip;
419  if ((res = av_get_packet(pb, pkt, len)) < 0)
420  return res;
421  } else { // ADPCM, PCM
422  if (len <= 0)
423  goto skip;
424  if ((res = av_get_packet(pb, pkt, len)) < 0)
425  return res;
426  }
427  pkt->pos = pos;
428  pkt->stream_index = st->index;
429  return pkt->size;
430  }
431  }
432  } else if (tag == TAG_JPEG2) {
433  for (i=0; i<s->nb_streams; i++) {
434  st = s->streams[i];
435  if (st->codec->codec_id == AV_CODEC_ID_MJPEG && st->id == -2)
436  break;
437  }
438  if (i == s->nb_streams) {
439  vst = avformat_new_stream(s, NULL);
440  if (!vst)
441  return AVERROR(ENOMEM);
442  vst->id = -2; /* -2 to avoid clash with video stream and audio stream */
445  avpriv_set_pts_info(vst, 64, 256, swf->frame_rate);
446  st = vst;
447  }
448  avio_rl16(pb); /* BITMAP_ID */
449  len -= 2;
450  if (len < 4)
451  goto skip;
452  if ((res = av_new_packet(pkt, len)) < 0)
453  return res;
454  avio_read(pb, pkt->data, 4);
455  if (AV_RB32(pkt->data) == 0xffd8ffd9 ||
456  AV_RB32(pkt->data) == 0xffd9ffd8) {
457  /* old SWF files containing SOI/EOI as data start */
458  /* files created by swink have reversed tag */
459  pkt->size -= 4;
460  avio_read(pb, pkt->data, pkt->size);
461  } else {
462  avio_read(pb, pkt->data + 4, pkt->size - 4);
463  }
464  pkt->pos = pos;
465  pkt->stream_index = st->index;
466  return pkt->size;
467  } else {
468  av_log(s, AV_LOG_DEBUG, "Unknown tag: %d\n", tag);
469  }
470  skip:
471  if(len<0)
472  av_log(s, AV_LOG_WARNING, "Cliping len %d\n", len);
473  len = FFMAX(0, len);
474  avio_skip(pb, len);
475  }
476 }
477 
478 #if CONFIG_ZLIB
479 static av_cold int swf_read_close(AVFormatContext *avctx)
480 {
481  SWFContext *s = avctx->priv_data;
482  inflateEnd(&s->zstream);
483  av_freep(&s->zbuf_in);
484  av_freep(&s->zbuf_out);
485  av_freep(&s->zpb);
486  return 0;
487 }
488 #endif
489 
491  .name = "swf",
492  .long_name = NULL_IF_CONFIG_SMALL("SWF (ShockWave Flash)"),
493  .priv_data_size = sizeof(SWFContext),
497 #if CONFIG_ZLIB
498  .read_close = swf_read_close,
499 #endif
500 };