4xm.c
Go to the documentation of this file.
1 /*
2  * 4X Technologies .4xm File Demuxer (no muxer)
3  * Copyright (c) 2003 The ffmpeg Project
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
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 
135  if ((unsigned)track >= UINT_MAX / sizeof(AudioTrack) - 1) {
136  av_log(s, AV_LOG_ERROR, "current_track too large\n");
137  return AVERROR_INVALIDDATA;
138  }
139  if (track < 0)
140  return AVERROR_INVALIDDATA;
141  if (track + 1 > fourxm->track_count) {
142  AudioTrack *tmp = av_realloc(fourxm->tracks,
143  (track + 1) * sizeof(AudioTrack));
144  if (!tmp)
145  return AVERROR(ENOMEM);
146  fourxm->tracks = tmp;
147  memset(&fourxm->tracks[fourxm->track_count], 0,
148  sizeof(AudioTrack) * (track + 1 - fourxm->track_count));
149  fourxm->track_count = track + 1;
150  }
151  fourxm->tracks[track].adpcm = AV_RL32(buf + 12);
152  fourxm->tracks[track].channels = AV_RL32(buf + 36);
153  fourxm->tracks[track].sample_rate = AV_RL32(buf + 40);
154  fourxm->tracks[track].bits = AV_RL32(buf + 44);
155  fourxm->tracks[track].audio_pts = 0;
156 
157  if (fourxm->tracks[track].channels <= 0 ||
158  fourxm->tracks[track].sample_rate <= 0 ||
159  fourxm->tracks[track].bits <= 0) {
160  av_log(s, AV_LOG_ERROR, "audio header invalid\n");
161  return AVERROR_INVALIDDATA;
162  }
163  /* allocate a new AVStream */
164  st = avformat_new_stream(s, NULL);
165  if (!st)
166  return AVERROR(ENOMEM);
167 
168  st->id = track;
169  avpriv_set_pts_info(st, 60, 1, fourxm->tracks[track].sample_rate);
170 
171  fourxm->tracks[track].stream_index = st->index;
172 
174  st->codec->codec_tag = 0;
175  st->codec->channels = fourxm->tracks[track].channels;
176  st->codec->sample_rate = fourxm->tracks[track].sample_rate;
177  st->codec->bits_per_coded_sample = fourxm->tracks[track].bits;
178  st->codec->bit_rate = st->codec->channels *
179  st->codec->sample_rate *
181  st->codec->block_align = st->codec->channels *
183 
184  if (fourxm->tracks[track].adpcm){
186  } else if (st->codec->bits_per_coded_sample == 8) {
188  } else
190 
191  return 0;
192 }
193 
195 {
196  AVIOContext *pb = s->pb;
197  unsigned int fourcc_tag;
198  unsigned int size;
199  int header_size;
200  FourxmDemuxContext *fourxm = s->priv_data;
201  unsigned char *header;
202  int i, ret;
203 
204  fourxm->track_count = 0;
205  fourxm->tracks = NULL;
206  fourxm->fps = 1.0;
207 
208  /* skip the first 3 32-bit numbers */
209  avio_skip(pb, 12);
210 
211  /* check for LIST-HEAD */
212  GET_LIST_HEADER();
213  header_size = size - 4;
214  if (fourcc_tag != HEAD_TAG || header_size < 0)
215  return AVERROR_INVALIDDATA;
216 
217  /* allocate space for the header and load the whole thing */
218  header = av_malloc(header_size);
219  if (!header)
220  return AVERROR(ENOMEM);
221  if (avio_read(pb, header, header_size) != header_size) {
222  av_free(header);
223  return AVERROR(EIO);
224  }
225 
226  /* take the lazy approach and search for any and all vtrk and strk chunks */
227  for (i = 0; i < header_size - 8; i++) {
228  fourcc_tag = AV_RL32(&header[i]);
229  size = AV_RL32(&header[i + 4]);
230 
231  if (fourcc_tag == std__TAG) {
232  if (header_size - i < 16) {
233  ret = AVERROR_INVALIDDATA;
234  goto fail;
235  }
236  fourxm->fps = av_int2float(AV_RL32(&header[i + 12]));
237  } else if (fourcc_tag == vtrk_TAG) {
238  if ((ret = parse_vtrk(s, fourxm, header + i, size,
239  header_size - i)) < 0)
240  goto fail;
241 
242  i += 8 + size;
243  } else if (fourcc_tag == strk_TAG) {
244  if ((ret = parse_strk(s, fourxm, header + i, size,
245  header_size - i)) < 0)
246  goto fail;
247 
248  i += 8 + size;
249  }
250  }
251 
252  /* skip over the LIST-MOVI chunk (which is where the stream should be */
253  GET_LIST_HEADER();
254  if (fourcc_tag != MOVI_TAG) {
255  ret = AVERROR_INVALIDDATA;
256  goto fail;
257  }
258 
259  av_free(header);
260  /* initialize context members */
261  fourxm->video_pts = -1; /* first frame will push to 0 */
262 
263  return 0;
264 fail:
265  av_freep(&fourxm->tracks);
266  av_free(header);
267  return ret;
268 }
269 
271  AVPacket *pkt)
272 {
273  FourxmDemuxContext *fourxm = s->priv_data;
274  AVIOContext *pb = s->pb;
275  unsigned int fourcc_tag;
276  unsigned int size;
277  int ret = 0;
278  unsigned int track_number;
279  int packet_read = 0;
280  unsigned char header[8];
281  int audio_frame_count;
282 
283  while (!packet_read) {
284  if ((ret = avio_read(s->pb, header, 8)) < 0)
285  return ret;
286  fourcc_tag = AV_RL32(&header[0]);
287  size = AV_RL32(&header[4]);
288  if (pb->eof_reached)
289  return AVERROR(EIO);
290  switch (fourcc_tag) {
291  case LIST_TAG:
292  /* this is a good time to bump the video pts */
293  fourxm->video_pts++;
294 
295  /* skip the LIST-* tag and move on to the next fourcc */
296  avio_rl32(pb);
297  break;
298 
299  case ifrm_TAG:
300  case pfrm_TAG:
301  case cfrm_TAG:
302  case ifr2_TAG:
303  case pfr2_TAG:
304  case cfr2_TAG:
305  /* allocate 8 more bytes than 'size' to account for fourcc
306  * and size */
307  if (size + 8 < size || av_new_packet(pkt, size + 8))
308  return AVERROR(EIO);
309  pkt->stream_index = fourxm->video_stream_index;
310  pkt->pts = fourxm->video_pts;
311  pkt->pos = avio_tell(s->pb);
312  memcpy(pkt->data, header, 8);
313  ret = avio_read(s->pb, &pkt->data[8], size);
314 
315  if (ret < 0) {
316  av_free_packet(pkt);
317  } else
318  packet_read = 1;
319  break;
320 
321  case snd__TAG:
322  track_number = avio_rl32(pb);
323  avio_skip(pb, 4);
324  size -= 8;
325 
326  if (track_number < fourxm->track_count &&
327  fourxm->tracks[track_number].channels > 0) {
328  ret = av_get_packet(s->pb, pkt, size);
329  if (ret < 0)
330  return AVERROR(EIO);
331  pkt->stream_index =
332  fourxm->tracks[track_number].stream_index;
333  pkt->pts = fourxm->tracks[track_number].audio_pts;
334  packet_read = 1;
335 
336  /* pts accounting */
337  audio_frame_count = size;
338  if (fourxm->tracks[track_number].adpcm)
339  audio_frame_count -= 2 * (fourxm->tracks[track_number].channels);
340  audio_frame_count /= fourxm->tracks[track_number].channels;
341  if (fourxm->tracks[track_number].adpcm) {
342  audio_frame_count *= 2;
343  } else
344  audio_frame_count /=
345  (fourxm->tracks[track_number].bits / 8);
346  fourxm->tracks[track_number].audio_pts += audio_frame_count;
347  } else {
348  avio_skip(pb, size);
349  }
350  break;
351 
352  default:
353  avio_skip(pb, size);
354  break;
355  }
356  }
357  return ret;
358 }
359 
361 {
362  FourxmDemuxContext *fourxm = s->priv_data;
363 
364  av_freep(&fourxm->tracks);
365 
366  return 0;
367 }
368 
370  .name = "4xm",
371  .long_name = NULL_IF_CONFIG_SMALL("4X Technologies"),
372  .priv_data_size = sizeof(FourxmDemuxContext),
377 };
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:61
int sample_rate
Definition: 4xm.c:66
Bytestream IO Context.
Definition: avio.h:68
int size
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:153
static int fourxm_probe(AVProbeData *p)
Definition: 4xm.c:83
int64_t audio_pts
Definition: 4xm.c:71
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:940
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:3283
#define ifr2_TAG
Definition: 4xm.c:50
static av_always_inline float av_int2float(uint32_t i)
Reinterpret a 32-bit integer as a float.
Definition: intfloat.h:40
int index
stream index in AVFormatContext
Definition: avformat.h:623
#define strk_SIZE
Definition: 4xm.c:56
static int parse_vtrk(AVFormatContext *s, FourxmDemuxContext *fourxm, uint8_t *buf, int size, int left)
Definition: 4xm.c:92
int channels
Definition: 4xm.c:68
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:2141
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:151
static int fourxm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: 4xm.c:270
int adpcm
Definition: 4xm.c:70
Format I/O context.
Definition: avformat.h:828
#define cfrm_TAG
Definition: 4xm.c:49
uint8_t
#define FOURXMV_TAG
Definition: 4xm.c:36
int id
Format-specific stream ID.
Definition: avformat.h:629
#define AV_WL32(p, d)
Definition: intreadwrite.h:255
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1454
#define vtrk_SIZE
Definition: 4xm.c:55
#define strk_TAG
Definition: 4xm.c:46
uint8_t * data
Definition: avcodec.h:915
Definition: 4xm.c:65
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:218
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:219
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2704
AVInputFormat ff_fourxm_demuxer
Definition: 4xm.c:369
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:446
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:56
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:139
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:546
#define RIFF_TAG
Definition: 4xm.c:35
int video_stream_index
Definition: 4xm.c:75
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:88
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:146
AVStream * avformat_new_stream(AVFormatContext *s, AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2736
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:641
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:340
int bit_rate
the average bitrate
Definition: avcodec.h:1404
static int fourxm_read_close(AVFormatContext *s)
Definition: 4xm.c:360
static int parse_strk(AVFormatContext *s, FourxmDemuxContext *fourxm, uint8_t *buf, int size, int left)
Definition: 4xm.c:123
int stream_index
Definition: 4xm.c:69
int64_t video_pts
Definition: 4xm.c:79
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:54
int track_count
Definition: 4xm.c:76
int width
picture width / height.
Definition: avcodec.h:1508
#define pfrm_TAG
Definition: 4xm.c:48
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: avio.h:210
AudioTrack * tracks
Definition: 4xm.c:77
#define AV_RL32
Definition: intreadwrite.h:146
#define MOVI_TAG
Definition: 4xm.c:40
static int fourxm_read_header(AVFormatContext *s)
Definition: 4xm.c:194
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:536
Stream structure.
Definition: avformat.h:622
NULL
Definition: eval.c:52
enum AVMediaType codec_type
Definition: avcodec.h:1347
enum AVCodecID codec_id
Definition: avcodec.h:1350
int sample_rate
samples per second
Definition: avcodec.h:2104
AVIOContext * pb
I/O context.
Definition: avformat.h:861
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1365
#define LIST_TAG
Definition: 4xm.c:37
int extradata_size
Definition: avcodec.h:1455
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
#define std__TAG
Definition: 4xm.c:43
struct AudioTrack AudioTrack
#define ifrm_TAG
Definition: 4xm.c:47
This structure contains the data a format has to probe a file.
Definition: avformat.h:338
#define snd__TAG
Definition: 4xm.c:53
Main libavformat public API header.
void * av_realloc(void *ptr, size_t size)
Allocate or reallocate a block of memory.
Definition: mem.c:116
#define vtrk_TAG
Definition: 4xm.c:45
int bits
Definition: 4xm.c:67
#define GET_LIST_HEADER()
Definition: 4xm.c:58
struct FourxmDemuxContext FourxmDemuxContext
int eof_reached
true if eof reached
Definition: avio.h:96
int channels
number of audio channels
Definition: avcodec.h:2105
void * priv_data
Format private data.
Definition: avformat.h:848
#define cfr2_TAG
Definition: 4xm.c:52
#define pfr2_TAG
Definition: 4xm.c:51
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:455
int stream_index
Definition: avcodec.h:917
This structure stores compressed data.
Definition: avcodec.h:898
#define HEAD_TAG
Definition: 4xm.c:38
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:908
float fps
Definition: 4xm.c:80