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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"
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 
287  len -= 2+1+2+2;
288 
289  switch (bmp_fmt) {
290  case 3: // PAL-8
291  linesize = width;
292  colormapsize = avio_r8(pb) + 1;
293  len--;
294  break;
295  case 4: // RGB15
296  linesize = width * 2;
297  break;
298  case 5: // RGB24 (0RGB)
299  linesize = width * 4;
300  break;
301  default:
302  av_log(s, AV_LOG_ERROR, "invalid bitmap format %d, skipped\n", bmp_fmt);
303  goto bitmap_end_skip;
304  }
305 
306  linesize = FFALIGN(linesize, 4);
307 
308  if (av_image_check_size(width, height, 0, s) < 0 ||
309  linesize >= INT_MAX / height ||
310  linesize * height >= INT_MAX - colormapsize * colormapbpp) {
311  av_log(s, AV_LOG_ERROR, "invalid frame size %dx%d\n", width, height);
312  goto bitmap_end_skip;
313  }
314 
315  out_len = colormapsize * colormapbpp + linesize * height;
316 
317  av_dlog(s, "bitmap: ch=%d fmt=%d %dx%d (linesize=%d) len=%d->%ld pal=%d\n",
318  ch_id, bmp_fmt, width, height, linesize, len, out_len, colormapsize);
319 
320  zbuf = av_malloc(len);
321  buf = av_malloc(out_len);
322  if (!zbuf || !buf) {
323  res = AVERROR(ENOMEM);
324  goto bitmap_end;
325  }
326 
327  len = avio_read(pb, zbuf, len);
328  if (len < 0 || (res = uncompress(buf, &out_len, zbuf, len)) != Z_OK) {
329  av_log(s, AV_LOG_WARNING, "Failed to uncompress one bitmap\n");
330  goto bitmap_end_skip;
331  }
332 
333  for (i = 0; i < s->nb_streams; i++) {
334  st = s->streams[i];
335  if (st->codec->codec_id == AV_CODEC_ID_RAWVIDEO && st->id == -3)
336  break;
337  }
338  if (i == s->nb_streams) {
339  vst = avformat_new_stream(s, NULL);
340  if (!vst) {
341  res = AVERROR(ENOMEM);
342  goto bitmap_end;
343  }
344  vst->id = -3; /* -3 to avoid clash with video stream and audio stream */
347  avpriv_set_pts_info(vst, 64, 256, swf->frame_rate);
348  st = vst;
349  }
350  st->codec->width = width;
351  st->codec->height = height;
352 
353  if ((res = av_new_packet(pkt, out_len - colormapsize * colormapbpp)) < 0)
354  goto bitmap_end;
355  pkt->pos = pos;
356  pkt->stream_index = st->index;
357 
358  switch (bmp_fmt) {
359  case 3:
360  st->codec->pix_fmt = AV_PIX_FMT_PAL8;
361  for (i = 0; i < colormapsize; i++)
362  if (alpha_bmp) colormap[i] = buf[3]<<24 | AV_RB24(buf + 4*i);
363  else colormap[i] = 0xffU <<24 | AV_RB24(buf + 3*i);
365  if (!pal) {
366  res = AVERROR(ENOMEM);
367  goto bitmap_end;
368  }
369  memcpy(pal, colormap, AVPALETTE_SIZE);
370  break;
371  case 4:
372  st->codec->pix_fmt = AV_PIX_FMT_RGB555;
373  break;
374  case 5:
375  st->codec->pix_fmt = alpha_bmp ? AV_PIX_FMT_ARGB : AV_PIX_FMT_0RGB;
376  break;
377  default:
378  av_assert0(0);
379  }
380 
381  if (linesize * height > pkt->size) {
382  res = AVERROR_INVALIDDATA;
383  goto bitmap_end;
384  }
385  memcpy(pkt->data, buf + colormapsize*colormapbpp, linesize * height);
386 
387  res = pkt->size;
388 
389 bitmap_end:
390  av_freep(&zbuf);
391  av_freep(&buf);
392  return res;
393 bitmap_end_skip:
394  av_freep(&zbuf);
395  av_freep(&buf);
396 #else
397  av_log(s, AV_LOG_ERROR, "this file requires zlib support compiled in\n");
398 #endif
399  } else if (tag == TAG_STREAMBLOCK) {
400  for (i = 0; i < s->nb_streams; i++) {
401  st = s->streams[i];
402  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1) {
403  if (st->codec->codec_id == AV_CODEC_ID_MP3) {
404  avio_skip(pb, 4);
405  len -= 4;
406  if (len <= 0)
407  goto skip;
408  if ((res = av_get_packet(pb, pkt, len)) < 0)
409  return res;
410  } else { // ADPCM, PCM
411  if (len <= 0)
412  goto skip;
413  if ((res = av_get_packet(pb, pkt, len)) < 0)
414  return res;
415  }
416  pkt->pos = pos;
417  pkt->stream_index = st->index;
418  return pkt->size;
419  }
420  }
421  } else if (tag == TAG_JPEG2) {
422  for (i=0; i<s->nb_streams; i++) {
423  st = s->streams[i];
424  if (st->codec->codec_id == AV_CODEC_ID_MJPEG && st->id == -2)
425  break;
426  }
427  if (i == s->nb_streams) {
428  vst = avformat_new_stream(s, NULL);
429  if (!vst)
430  return AVERROR(ENOMEM);
431  vst->id = -2; /* -2 to avoid clash with video stream and audio stream */
434  avpriv_set_pts_info(vst, 64, 256, swf->frame_rate);
435  st = vst;
436  }
437  avio_rl16(pb); /* BITMAP_ID */
438  len -= 2;
439  if (len < 4)
440  goto skip;
441  if ((res = av_new_packet(pkt, len)) < 0)
442  return res;
443  avio_read(pb, pkt->data, 4);
444  if (AV_RB32(pkt->data) == 0xffd8ffd9 ||
445  AV_RB32(pkt->data) == 0xffd9ffd8) {
446  /* old SWF files containing SOI/EOI as data start */
447  /* files created by swink have reversed tag */
448  pkt->size -= 4;
449  avio_read(pb, pkt->data, pkt->size);
450  } else {
451  avio_read(pb, pkt->data + 4, pkt->size - 4);
452  }
453  pkt->pos = pos;
454  pkt->stream_index = st->index;
455  return pkt->size;
456  } else {
457  av_log(s, AV_LOG_DEBUG, "Unknown tag: %d\n", tag);
458  }
459  skip:
460  if(len<0)
461  av_log(s, AV_LOG_WARNING, "Cliping len %d\n", len);
462  len = FFMAX(0, len);
463  avio_skip(pb, len);
464  }
465 }
466 
467 #if CONFIG_ZLIB
468 static av_cold int swf_read_close(AVFormatContext *avctx)
469 {
470  SWFContext *s = avctx->priv_data;
471  inflateEnd(&s->zstream);
472  av_freep(&s->zbuf_in);
473  av_freep(&s->zbuf_out);
474  av_freep(&s->zpb);
475  return 0;
476 }
477 #endif
478 
480  .name = "swf",
481  .long_name = NULL_IF_CONFIG_SMALL("SWF (ShockWave Flash)"),
482  .priv_data_size = sizeof(SWFContext),
486 #if CONFIG_ZLIB
487  .read_close = swf_read_close,
488 #endif
489 };