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4xm.c
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1 /*
2  * 4X Technologies .4xm File Demuxer (no muxer)
3  * Copyright (c) 2003 The ffmpeg Project
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  * 4X Technologies file demuxer
25  * by Mike Melanson (melanson@pcisys.net)
26  * for more information on the .4xm file format, visit:
27  * http://www.pcisys.net/~melanson/codecs/
28  */
29 
30 #include "libavutil/intreadwrite.h"
31 #include "libavutil/intfloat.h"
32 #include "avformat.h"
33 #include "internal.h"
34 
35 #define RIFF_TAG MKTAG('R', 'I', 'F', 'F')
36 #define FOURXMV_TAG MKTAG('4', 'X', 'M', 'V')
37 #define LIST_TAG MKTAG('L', 'I', 'S', 'T')
38 #define HEAD_TAG MKTAG('H', 'E', 'A', 'D')
39 #define TRK__TAG MKTAG('T', 'R', 'K', '_')
40 #define MOVI_TAG MKTAG('M', 'O', 'V', 'I')
41 #define VTRK_TAG MKTAG('V', 'T', 'R', 'K')
42 #define STRK_TAG MKTAG('S', 'T', 'R', 'K')
43 #define std__TAG MKTAG('s', 't', 'd', '_')
44 #define name_TAG MKTAG('n', 'a', 'm', 'e')
45 #define vtrk_TAG MKTAG('v', 't', 'r', 'k')
46 #define strk_TAG MKTAG('s', 't', 'r', 'k')
47 #define ifrm_TAG MKTAG('i', 'f', 'r', 'm')
48 #define pfrm_TAG MKTAG('p', 'f', 'r', 'm')
49 #define cfrm_TAG MKTAG('c', 'f', 'r', 'm')
50 #define ifr2_TAG MKTAG('i', 'f', 'r', '2')
51 #define pfr2_TAG MKTAG('p', 'f', 'r', '2')
52 #define cfr2_TAG MKTAG('c', 'f', 'r', '2')
53 #define snd__TAG MKTAG('s', 'n', 'd', '_')
54 
55 #define vtrk_SIZE 0x44
56 #define strk_SIZE 0x28
57 
58 #define GET_LIST_HEADER() \
59  fourcc_tag = avio_rl32(pb); \
60  size = avio_rl32(pb); \
61  if (fourcc_tag != LIST_TAG) \
62  return AVERROR_INVALIDDATA; \
63  fourcc_tag = avio_rl32(pb);
64 
65 typedef struct AudioTrack {
67  int bits;
68  int channels;
70  int adpcm;
71  int64_t audio_pts;
72 } AudioTrack;
73 
74 typedef struct FourxmDemuxContext {
78 
79  int64_t video_pts;
80  float fps;
82 
83 static int fourxm_probe(AVProbeData *p)
84 {
85  if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
86  (AV_RL32(&p->buf[8]) != FOURXMV_TAG))
87  return 0;
88 
89  return AVPROBE_SCORE_MAX;
90 }
91 
93  FourxmDemuxContext *fourxm, uint8_t *buf, int size,
94  int left)
95 {
96  AVStream *st;
97  /* check that there is enough data */
98  if (size != vtrk_SIZE || left < size + 8) {
99  return AVERROR_INVALIDDATA;
100  }
101 
102  /* allocate a new AVStream */
103  st = avformat_new_stream(s, NULL);
104  if (!st)
105  return AVERROR(ENOMEM);
106 
107  avpriv_set_pts_info(st, 60, 1, fourxm->fps);
108 
109  fourxm->video_stream_index = st->index;
110 
113  st->codec->extradata_size = 4;
114  st->codec->extradata = av_malloc(4);
115  AV_WL32(st->codec->extradata, AV_RL32(buf + 16));
116  st->codec->width = AV_RL32(buf + 36);
117  st->codec->height = AV_RL32(buf + 40);
118 
119  return 0;
120 }
121 
122 
124  FourxmDemuxContext *fourxm, uint8_t *buf, int size,
125  int left)
126 {
127  AVStream *st;
128  int track;
129  /* check that there is enough data */
130  if (size != strk_SIZE || left < size + 8)
131  return AVERROR_INVALIDDATA;
132 
133  track = AV_RL32(buf + 8);
134  if ((unsigned)track >= UINT_MAX / sizeof(AudioTrack) - 1) {
135  av_log(s, AV_LOG_ERROR, "current_track too large\n");
136  return AVERROR_INVALIDDATA;
137  }
138  if (track + 1 > fourxm->track_count) {
139  if (av_reallocp_array(&fourxm->tracks, track + 1, sizeof(AudioTrack)))
140  return AVERROR(ENOMEM);
141  memset(&fourxm->tracks[fourxm->track_count], 0,
142  sizeof(AudioTrack) * (track + 1 - fourxm->track_count));
143  fourxm->track_count = track + 1;
144  }
145  fourxm->tracks[track].adpcm = AV_RL32(buf + 12);
146  fourxm->tracks[track].channels = AV_RL32(buf + 36);
147  fourxm->tracks[track].sample_rate = AV_RL32(buf + 40);
148  fourxm->tracks[track].bits = AV_RL32(buf + 44);
149  fourxm->tracks[track].audio_pts = 0;
150 
151  if (fourxm->tracks[track].channels <= 0 ||
152  fourxm->tracks[track].sample_rate <= 0 ||
153  fourxm->tracks[track].bits < 0) {
154  av_log(s, AV_LOG_ERROR, "audio header invalid\n");
155  return AVERROR_INVALIDDATA;
156  }
157  if (!fourxm->tracks[track].adpcm && fourxm->tracks[track].bits<8) {
158  av_log(s, AV_LOG_ERROR, "bits unspecified for non ADPCM\n");
159  return AVERROR_INVALIDDATA;
160  }
161 
162  /* allocate a new AVStream */
163  st = avformat_new_stream(s, NULL);
164  if (!st)
165  return AVERROR(ENOMEM);
166 
167  st->id = track;
168  avpriv_set_pts_info(st, 60, 1, fourxm->tracks[track].sample_rate);
169 
170  fourxm->tracks[track].stream_index = st->index;
171 
173  st->codec->codec_tag = 0;
174  st->codec->channels = fourxm->tracks[track].channels;
175  st->codec->sample_rate = fourxm->tracks[track].sample_rate;
176  st->codec->bits_per_coded_sample = fourxm->tracks[track].bits;
177  st->codec->bit_rate = st->codec->channels *
178  st->codec->sample_rate *
180  st->codec->block_align = st->codec->channels *
182 
183  if (fourxm->tracks[track].adpcm){
185  } else if (st->codec->bits_per_coded_sample == 8) {
187  } else
189 
190  return 0;
191 }
192 
194 {
195  AVIOContext *pb = s->pb;
196  unsigned int fourcc_tag;
197  unsigned int size;
198  int header_size;
199  FourxmDemuxContext *fourxm = s->priv_data;
200  unsigned char *header;
201  int i, ret;
202 
203  fourxm->track_count = 0;
204  fourxm->tracks = NULL;
205  fourxm->fps = 1.0;
206 
207  /* skip the first 3 32-bit numbers */
208  avio_skip(pb, 12);
209 
210  /* check for LIST-HEAD */
211  GET_LIST_HEADER();
212  header_size = size - 4;
213  if (fourcc_tag != HEAD_TAG || header_size < 0)
214  return AVERROR_INVALIDDATA;
215 
216  /* allocate space for the header and load the whole thing */
217  header = av_malloc(header_size);
218  if (!header)
219  return AVERROR(ENOMEM);
220  if (avio_read(pb, header, header_size) != header_size) {
221  av_free(header);
222  return AVERROR(EIO);
223  }
224 
225  /* take the lazy approach and search for any and all vtrk and strk chunks */
226  for (i = 0; i < header_size - 8; i++) {
227  fourcc_tag = AV_RL32(&header[i]);
228  size = AV_RL32(&header[i + 4]);
229  if (size > header_size - i - 8 && (fourcc_tag == vtrk_TAG || fourcc_tag == strk_TAG)) {
230  av_log(s, AV_LOG_ERROR, "chunk larger than array %d>%d\n", size, header_size - i - 8);
231  return AVERROR_INVALIDDATA;
232  }
233 
234  if (fourcc_tag == std__TAG) {
235  if (header_size - i < 16) {
236  av_log(s, AV_LOG_ERROR, "std TAG truncated\n");
237  ret = AVERROR_INVALIDDATA;
238  goto fail;
239  }
240  fourxm->fps = av_int2float(AV_RL32(&header[i + 12]));
241  } else if (fourcc_tag == vtrk_TAG) {
242  if ((ret = parse_vtrk(s, fourxm, header + i, size,
243  header_size - i)) < 0)
244  goto fail;
245 
246  i += 8 + size;
247  } else if (fourcc_tag == strk_TAG) {
248  if ((ret = parse_strk(s, fourxm, header + i, size,
249  header_size - i)) < 0)
250  goto fail;
251 
252  i += 8 + size;
253  }
254  }
255 
256  /* skip over the LIST-MOVI chunk (which is where the stream should be */
257  GET_LIST_HEADER();
258  if (fourcc_tag != MOVI_TAG) {
259  ret = AVERROR_INVALIDDATA;
260  goto fail;
261  }
262 
263  av_free(header);
264  /* initialize context members */
265  fourxm->video_pts = -1; /* first frame will push to 0 */
266 
267  return 0;
268 fail:
269  av_freep(&fourxm->tracks);
270  av_free(header);
271  return ret;
272 }
273 
275  AVPacket *pkt)
276 {
277  FourxmDemuxContext *fourxm = s->priv_data;
278  AVIOContext *pb = s->pb;
279  unsigned int fourcc_tag;
280  unsigned int size;
281  int ret = 0;
282  unsigned int track_number;
283  int packet_read = 0;
284  unsigned char header[8];
285  int audio_frame_count;
286 
287  while (!packet_read) {
288  if ((ret = avio_read(s->pb, header, 8)) < 0)
289  return ret;
290  fourcc_tag = AV_RL32(&header[0]);
291  size = AV_RL32(&header[4]);
292  if (url_feof(pb))
293  return AVERROR(EIO);
294  switch (fourcc_tag) {
295  case LIST_TAG:
296  /* this is a good time to bump the video pts */
297  fourxm->video_pts++;
298 
299  /* skip the LIST-* tag and move on to the next fourcc */
300  avio_rl32(pb);
301  break;
302 
303  case ifrm_TAG:
304  case pfrm_TAG:
305  case cfrm_TAG:
306  case ifr2_TAG:
307  case pfr2_TAG:
308  case cfr2_TAG:
309  /* allocate 8 more bytes than 'size' to account for fourcc
310  * and size */
311  if (size + 8 < size || av_new_packet(pkt, size + 8))
312  return AVERROR(EIO);
313  pkt->stream_index = fourxm->video_stream_index;
314  pkt->pts = fourxm->video_pts;
315  pkt->pos = avio_tell(s->pb);
316  memcpy(pkt->data, header, 8);
317  ret = avio_read(s->pb, &pkt->data[8], size);
318 
319  if (ret < 0) {
320  av_free_packet(pkt);
321  } else
322  packet_read = 1;
323  break;
324 
325  case snd__TAG:
326  track_number = avio_rl32(pb);
327  avio_skip(pb, 4);
328  size -= 8;
329 
330  if (track_number < fourxm->track_count &&
331  fourxm->tracks[track_number].channels > 0) {
332  ret = av_get_packet(s->pb, pkt, size);
333  if (ret < 0)
334  return AVERROR(EIO);
335  pkt->stream_index =
336  fourxm->tracks[track_number].stream_index;
337  pkt->pts = fourxm->tracks[track_number].audio_pts;
338  packet_read = 1;
339 
340  /* pts accounting */
341  audio_frame_count = size;
342  if (fourxm->tracks[track_number].adpcm)
343  audio_frame_count -= 2 * (fourxm->tracks[track_number].channels);
344  audio_frame_count /= fourxm->tracks[track_number].channels;
345  if (fourxm->tracks[track_number].adpcm) {
346  audio_frame_count *= 2;
347  } else
348  audio_frame_count /=
349  (fourxm->tracks[track_number].bits / 8);
350  fourxm->tracks[track_number].audio_pts += audio_frame_count;
351  } else {
352  avio_skip(pb, size);
353  }
354  break;
355 
356  default:
357  avio_skip(pb, size);
358  break;
359  }
360  }
361  return ret;
362 }
363 
365 {
366  FourxmDemuxContext *fourxm = s->priv_data;
367 
368  av_freep(&fourxm->tracks);
369 
370  return 0;
371 }
372 
374  .name = "4xm",
375  .long_name = NULL_IF_CONFIG_SMALL("4X Technologies"),
376  .priv_data_size = sizeof(FourxmDemuxContext),
381 };