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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 {
66  int sample_rate;
67  int bits;
68  int channels;
69  int stream_index;
70  int adpcm;
71  int64_t audio_pts;
72 } AudioTrack;
73 
74 typedef struct FourxmDemuxContext {
75  int width;
76  int height;
77  int video_stream_index;
78  int track_count;
79  AudioTrack *tracks;
80 
81  int64_t video_pts;
82  float fps;
83 } FourxmDemuxContext;
84 
85 static int fourxm_probe(AVProbeData *p)
86 {
87  if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
88  (AV_RL32(&p->buf[8]) != FOURXMV_TAG))
89  return 0;
90 
91  return AVPROBE_SCORE_MAX;
92 }
93 
94 static int fourxm_read_header(AVFormatContext *s)
95 {
96  AVIOContext *pb = s->pb;
97  unsigned int fourcc_tag;
98  unsigned int size;
99  int header_size;
100  FourxmDemuxContext *fourxm = s->priv_data;
101  unsigned char *header;
102  int i, ret;
103  AVStream *st;
104 
105  fourxm->track_count = 0;
106  fourxm->tracks = NULL;
107  fourxm->fps = 1.0;
108 
109  /* skip the first 3 32-bit numbers */
110  avio_skip(pb, 12);
111 
112  /* check for LIST-HEAD */
113  GET_LIST_HEADER();
114  header_size = size - 4;
115  if (fourcc_tag != HEAD_TAG || header_size < 0)
116  return AVERROR_INVALIDDATA;
117 
118  /* allocate space for the header and load the whole thing */
119  header = av_malloc(header_size);
120  if (!header)
121  return AVERROR(ENOMEM);
122  if (avio_read(pb, header, header_size) != header_size){
123  av_free(header);
124  return AVERROR(EIO);
125  }
126 
127  /* take the lazy approach and search for any and all vtrk and strk chunks */
128  for (i = 0; i < header_size - 8; i++) {
129  fourcc_tag = AV_RL32(&header[i]);
130  size = AV_RL32(&header[i + 4]);
131  if (size > header_size - i - 8 && (fourcc_tag == vtrk_TAG || fourcc_tag == strk_TAG)) {
132  av_log(s, AV_LOG_ERROR, "chunk larger than array %d>%d\n", size, header_size - i - 8);
133  return AVERROR_INVALIDDATA;
134  }
135 
136  if (fourcc_tag == std__TAG) {
137  if (header_size < i + 16) {
138  av_log(s, AV_LOG_ERROR, "std TAG truncated\n");
139  return AVERROR_INVALIDDATA;
140  }
141  fourxm->fps = av_int2float(AV_RL32(&header[i + 12]));
142  } else if (fourcc_tag == vtrk_TAG) {
143  /* check that there is enough data */
144  if (size != vtrk_SIZE) {
145  ret= AVERROR_INVALIDDATA;
146  goto fail;
147  }
148  fourxm->width = AV_RL32(&header[i + 36]);
149  fourxm->height = AV_RL32(&header[i + 40]);
150 
151  /* allocate a new AVStream */
152  st = avformat_new_stream(s, NULL);
153  if (!st){
154  ret= AVERROR(ENOMEM);
155  goto fail;
156  }
157  avpriv_set_pts_info(st, 60, 1, fourxm->fps);
158 
159  fourxm->video_stream_index = st->index;
160 
161  st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
162  st->codec->codec_id = AV_CODEC_ID_4XM;
163  st->codec->extradata_size = 4;
164  st->codec->extradata = av_malloc(4);
165  AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16]));
166  st->codec->width = fourxm->width;
167  st->codec->height = fourxm->height;
168 
169  i += 8 + size;
170  } else if (fourcc_tag == strk_TAG) {
171  int current_track;
172  /* check that there is enough data */
173  if (size != strk_SIZE) {
174  ret= AVERROR_INVALIDDATA;
175  goto fail;
176  }
177  current_track = AV_RL32(&header[i + 8]);
178  if((unsigned)current_track >= UINT_MAX / sizeof(AudioTrack) - 1){
179  av_log(s, AV_LOG_ERROR, "current_track too large\n");
180  ret = AVERROR_INVALIDDATA;
181  goto fail;
182  }
183  if (current_track + 1 > fourxm->track_count) {
184  fourxm->tracks = av_realloc_f(fourxm->tracks,
185  sizeof(AudioTrack),
186  current_track + 1);
187  if (!fourxm->tracks) {
188  ret = AVERROR(ENOMEM);
189  goto fail;
190  }
191  memset(&fourxm->tracks[fourxm->track_count], 0,
192  sizeof(AudioTrack) * (current_track + 1 - fourxm->track_count));
193  fourxm->track_count = current_track + 1;
194  }
195  fourxm->tracks[current_track].adpcm = AV_RL32(&header[i + 12]);
196  fourxm->tracks[current_track].channels = AV_RL32(&header[i + 36]);
197  fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]);
198  fourxm->tracks[current_track].bits = AV_RL32(&header[i + 44]);
199  fourxm->tracks[current_track].audio_pts = 0;
200  if( fourxm->tracks[current_track].channels <= 0
201  || fourxm->tracks[current_track].sample_rate <= 0
202  || fourxm->tracks[current_track].bits < 0){
203  av_log(s, AV_LOG_ERROR, "audio header invalid\n");
204  ret = AVERROR_INVALIDDATA;
205  goto fail;
206  }
207  if(!fourxm->tracks[current_track].adpcm && fourxm->tracks[current_track].bits<8){
208  av_log(s, AV_LOG_ERROR, "bits unspecified for non ADPCM\n");
209  ret = AVERROR_INVALIDDATA;
210  goto fail;
211  }
212  i += 8 + size;
213 
214  /* allocate a new AVStream */
215  st = avformat_new_stream(s, NULL);
216  if (!st){
217  ret= AVERROR(ENOMEM);
218  goto fail;
219  }
220 
221  st->id = current_track;
222  avpriv_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
223 
224  fourxm->tracks[current_track].stream_index = st->index;
225 
226  st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
227  st->codec->codec_tag = 0;
228  st->codec->channels = fourxm->tracks[current_track].channels;
229  st->codec->sample_rate = fourxm->tracks[current_track].sample_rate;
230  st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits;
231  st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
232  st->codec->bits_per_coded_sample;
233  st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
234  if (fourxm->tracks[current_track].adpcm){
235  st->codec->codec_id = AV_CODEC_ID_ADPCM_4XM;
236  }else if (st->codec->bits_per_coded_sample == 8){
237  st->codec->codec_id = AV_CODEC_ID_PCM_U8;
238  }else
239  st->codec->codec_id = AV_CODEC_ID_PCM_S16LE;
240  }
241  }
242 
243  /* skip over the LIST-MOVI chunk (which is where the stream should be */
244  GET_LIST_HEADER();
245  if (fourcc_tag != MOVI_TAG){
246  ret= AVERROR_INVALIDDATA;
247  goto fail;
248  }
249 
250  av_free(header);
251  /* initialize context members */
252  fourxm->video_pts = -1; /* first frame will push to 0 */
253 
254  return 0;
255 fail:
256  av_freep(&fourxm->tracks);
257  av_free(header);
258  return ret;
259 }
260 
261 static int fourxm_read_packet(AVFormatContext *s,
262  AVPacket *pkt)
263 {
264  FourxmDemuxContext *fourxm = s->priv_data;
265  AVIOContext *pb = s->pb;
266  unsigned int fourcc_tag;
267  unsigned int size;
268  int ret = 0;
269  unsigned int track_number;
270  int packet_read = 0;
271  unsigned char header[8];
272  int audio_frame_count;
273 
274  while (!packet_read) {
275 
276  if ((ret = avio_read(s->pb, header, 8)) < 0)
277  return ret;
278  fourcc_tag = AV_RL32(&header[0]);
279  size = AV_RL32(&header[4]);
280  if (url_feof(pb))
281  return AVERROR(EIO);
282  switch (fourcc_tag) {
283 
284  case LIST_TAG:
285  /* this is a good time to bump the video pts */
286  fourxm->video_pts ++;
287 
288  /* skip the LIST-* tag and move on to the next fourcc */
289  avio_rl32(pb);
290  break;
291 
292  case ifrm_TAG:
293  case pfrm_TAG:
294  case cfrm_TAG:
295  case ifr2_TAG:
296  case pfr2_TAG:
297  case cfr2_TAG:
298  /* allocate 8 more bytes than 'size' to account for fourcc
299  * and size */
300  if (size + 8 < size || av_new_packet(pkt, size + 8))
301  return AVERROR(EIO);
302  pkt->stream_index = fourxm->video_stream_index;
303  pkt->pts = fourxm->video_pts;
304  pkt->pos = avio_tell(s->pb);
305  memcpy(pkt->data, header, 8);
306  ret = avio_read(s->pb, &pkt->data[8], size);
307 
308  if (ret < 0){
309  av_free_packet(pkt);
310  }else
311  packet_read = 1;
312  break;
313 
314  case snd__TAG:
315  track_number = avio_rl32(pb);
316  avio_skip(pb, 4);
317  size-=8;
318 
319  if (track_number < fourxm->track_count && fourxm->tracks[track_number].channels>0) {
320  ret= av_get_packet(s->pb, pkt, size);
321  if(ret<0)
322  return AVERROR(EIO);
323  pkt->stream_index =
324  fourxm->tracks[track_number].stream_index;
325  pkt->pts = fourxm->tracks[track_number].audio_pts;
326  packet_read = 1;
327 
328  /* pts accounting */
329  audio_frame_count = size;
330  if (fourxm->tracks[track_number].adpcm)
331  audio_frame_count -=
332  2 * (fourxm->tracks[track_number].channels);
333  audio_frame_count /=
334  fourxm->tracks[track_number].channels;
335  if (fourxm->tracks[track_number].adpcm){
336  audio_frame_count *= 2;
337  }else
338  audio_frame_count /=
339  (fourxm->tracks[track_number].bits / 8);
340  fourxm->tracks[track_number].audio_pts += audio_frame_count;
341 
342  } else {
343  avio_skip(pb, size);
344  }
345  break;
346 
347  default:
348  avio_skip(pb, size);
349  break;
350  }
351  }
352  return ret;
353 }
354 
355 static int fourxm_read_close(AVFormatContext *s)
356 {
357  FourxmDemuxContext *fourxm = s->priv_data;
358 
359  av_freep(&fourxm->tracks);
360 
361  return 0;
362 }
363 
364 AVInputFormat ff_fourxm_demuxer = {
365  .name = "4xm",
366  .long_name = NULL_IF_CONFIG_SMALL("4X Technologies"),
367  .priv_data_size = sizeof(FourxmDemuxContext),
368  .read_probe = fourxm_probe,
369  .read_header = fourxm_read_header,
370  .read_packet = fourxm_read_packet,
371  .read_close = fourxm_read_close,
372 };
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