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 {
75  int width;
76  int height;
80 
81  int64_t video_pts;
82  float fps;
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 
96 {
97  AVIOContext *pb = s->pb;
98  unsigned int fourcc_tag;
99  unsigned int size;
100  int header_size;
101  FourxmDemuxContext *fourxm = s->priv_data;
102  unsigned char *header;
103  int i, ret;
104  AVStream *st;
105 
106  fourxm->track_count = 0;
107  fourxm->tracks = NULL;
108  fourxm->fps = 1.0;
109 
110  /* skip the first 3 32-bit numbers */
111  avio_skip(pb, 12);
112 
113  /* check for LIST-HEAD */
114  GET_LIST_HEADER();
115  header_size = size - 4;
116  if (fourcc_tag != HEAD_TAG || header_size < 0)
117  return AVERROR_INVALIDDATA;
118 
119  /* allocate space for the header and load the whole thing */
120  header = av_malloc(header_size);
121  if (!header)
122  return AVERROR(ENOMEM);
123  if (avio_read(pb, header, header_size) != header_size){
124  av_free(header);
125  return AVERROR(EIO);
126  }
127 
128  /* take the lazy approach and search for any and all vtrk and strk chunks */
129  for (i = 0; i < header_size - 8; i++) {
130  fourcc_tag = AV_RL32(&header[i]);
131  size = AV_RL32(&header[i + 4]);
132 
133  if (fourcc_tag == std__TAG) {
134  fourxm->fps = av_int2float(AV_RL32(&header[i + 12]));
135  } else if (fourcc_tag == vtrk_TAG) {
136  /* check that there is enough data */
137  if (size != vtrk_SIZE) {
138  ret= AVERROR_INVALIDDATA;
139  goto fail;
140  }
141  fourxm->width = AV_RL32(&header[i + 36]);
142  fourxm->height = AV_RL32(&header[i + 40]);
143 
144  /* allocate a new AVStream */
145  st = avformat_new_stream(s, NULL);
146  if (!st){
147  ret= AVERROR(ENOMEM);
148  goto fail;
149  }
150  avpriv_set_pts_info(st, 60, 1, fourxm->fps);
151 
152  fourxm->video_stream_index = st->index;
153 
155  st->codec->codec_id = CODEC_ID_4XM;
156  st->codec->extradata_size = 4;
157  st->codec->extradata = av_malloc(4);
158  AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16]));
159  st->codec->width = fourxm->width;
160  st->codec->height = fourxm->height;
161 
162  i += 8 + size;
163  } else if (fourcc_tag == strk_TAG) {
164  int current_track;
165  /* check that there is enough data */
166  if (size != strk_SIZE) {
167  ret= AVERROR_INVALIDDATA;
168  goto fail;
169  }
170  current_track = AV_RL32(&header[i + 8]);
171  if((unsigned)current_track >= UINT_MAX / sizeof(AudioTrack) - 1){
172  av_log(s, AV_LOG_ERROR, "current_track too large\n");
173  ret= -1;
174  goto fail;
175  }
176  if (current_track + 1 > fourxm->track_count) {
177  fourxm->tracks = av_realloc(fourxm->tracks,
178  (current_track + 1) * sizeof(AudioTrack));
179  if (!fourxm->tracks) {
180  ret = AVERROR(ENOMEM);
181  goto fail;
182  }
183  memset(&fourxm->tracks[fourxm->track_count], 0,
184  sizeof(AudioTrack) * (current_track + 1 - fourxm->track_count));
185  fourxm->track_count = current_track + 1;
186  }
187  fourxm->tracks[current_track].adpcm = AV_RL32(&header[i + 12]);
188  fourxm->tracks[current_track].channels = AV_RL32(&header[i + 36]);
189  fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]);
190  fourxm->tracks[current_track].bits = AV_RL32(&header[i + 44]);
191  fourxm->tracks[current_track].audio_pts = 0;
192  if( fourxm->tracks[current_track].channels <= 0
193  || fourxm->tracks[current_track].sample_rate <= 0
194  || fourxm->tracks[current_track].bits < 0){
195  av_log(s, AV_LOG_ERROR, "audio header invalid\n");
196  ret= -1;
197  goto fail;
198  }
199  i += 8 + size;
200 
201  /* allocate a new AVStream */
202  st = avformat_new_stream(s, NULL);
203  if (!st){
204  ret= AVERROR(ENOMEM);
205  goto fail;
206  }
207 
208  st->id = current_track;
209  avpriv_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
210 
211  fourxm->tracks[current_track].stream_index = st->index;
212 
214  st->codec->codec_tag = 0;
215  st->codec->channels = fourxm->tracks[current_track].channels;
216  st->codec->sample_rate = fourxm->tracks[current_track].sample_rate;
217  st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits;
218  st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
221  if (fourxm->tracks[current_track].adpcm){
223  }else if (st->codec->bits_per_coded_sample == 8){
225  }else
227  }
228  }
229 
230  /* skip over the LIST-MOVI chunk (which is where the stream should be */
231  GET_LIST_HEADER();
232  if (fourcc_tag != MOVI_TAG){
233  ret= AVERROR_INVALIDDATA;
234  goto fail;
235  }
236 
237  av_free(header);
238  /* initialize context members */
239  fourxm->video_pts = -1; /* first frame will push to 0 */
240 
241  return 0;
242 fail:
243  av_freep(&fourxm->tracks);
244  av_free(header);
245  return ret;
246 }
247 
249  AVPacket *pkt)
250 {
251  FourxmDemuxContext *fourxm = s->priv_data;
252  AVIOContext *pb = s->pb;
253  unsigned int fourcc_tag;
254  unsigned int size;
255  int ret = 0;
256  unsigned int track_number;
257  int packet_read = 0;
258  unsigned char header[8];
259  int audio_frame_count;
260 
261  while (!packet_read) {
262 
263  if ((ret = avio_read(s->pb, header, 8)) < 0)
264  return ret;
265  fourcc_tag = AV_RL32(&header[0]);
266  size = AV_RL32(&header[4]);
267  if (pb->eof_reached)
268  return AVERROR(EIO);
269  switch (fourcc_tag) {
270 
271  case LIST_TAG:
272  /* this is a good time to bump the video pts */
273  fourxm->video_pts ++;
274 
275  /* skip the LIST-* tag and move on to the next fourcc */
276  avio_rl32(pb);
277  break;
278 
279  case ifrm_TAG:
280  case pfrm_TAG:
281  case cfrm_TAG:
282  case ifr2_TAG:
283  case pfr2_TAG:
284  case cfr2_TAG:
285  /* allocate 8 more bytes than 'size' to account for fourcc
286  * and size */
287  if (size + 8 < size || av_new_packet(pkt, size + 8))
288  return AVERROR(EIO);
289  pkt->stream_index = fourxm->video_stream_index;
290  pkt->pts = fourxm->video_pts;
291  pkt->pos = avio_tell(s->pb);
292  memcpy(pkt->data, header, 8);
293  ret = avio_read(s->pb, &pkt->data[8], size);
294 
295  if (ret < 0){
296  av_free_packet(pkt);
297  }else
298  packet_read = 1;
299  break;
300 
301  case snd__TAG:
302  track_number = avio_rl32(pb);
303  avio_skip(pb, 4);
304  size-=8;
305 
306  if (track_number < fourxm->track_count && fourxm->tracks[track_number].channels>0) {
307  ret= av_get_packet(s->pb, pkt, size);
308  if(ret<0)
309  return AVERROR(EIO);
310  pkt->stream_index =
311  fourxm->tracks[track_number].stream_index;
312  pkt->pts = fourxm->tracks[track_number].audio_pts;
313  packet_read = 1;
314 
315  /* pts accounting */
316  audio_frame_count = size;
317  if (fourxm->tracks[track_number].adpcm)
318  audio_frame_count -=
319  2 * (fourxm->tracks[track_number].channels);
320  audio_frame_count /=
321  fourxm->tracks[track_number].channels;
322  if (fourxm->tracks[track_number].adpcm){
323  audio_frame_count *= 2;
324  }else
325  audio_frame_count /=
326  (fourxm->tracks[track_number].bits / 8);
327  fourxm->tracks[track_number].audio_pts += audio_frame_count;
328 
329  } else {
330  avio_skip(pb, size);
331  }
332  break;
333 
334  default:
335  avio_skip(pb, size);
336  break;
337  }
338  }
339  return ret;
340 }
341 
343 {
344  FourxmDemuxContext *fourxm = s->priv_data;
345 
346  av_freep(&fourxm->tracks);
347 
348  return 0;
349 }
350 
352  .name = "4xm",
353  .long_name = NULL_IF_CONFIG_SMALL("4X Technologies format"),
354  .priv_data_size = sizeof(FourxmDemuxContext),
359 };
int sample_rate
Definition: 4xm.c:66
Bytestream IO Context.
Definition: avio.h:68
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
int size
static int fourxm_probe(AVProbeData *p)
Definition: 4xm.c:85
int64_t audio_pts
Definition: 4xm.c:71
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:933
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the pts for a given stream.
Definition: utils.c:3828
#define ifr2_TAG
Definition: 4xm.c:50
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:60
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:621
#define strk_SIZE
Definition: 4xm.c:56
void * av_realloc(void *ptr, size_t size)
Allocate or reallocate a block of memory.
Definition: mem.c:117
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:1751
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:147
static int fourxm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: 4xm.c:248
int adpcm
Definition: 4xm.c:70
Format I/O context.
Definition: avformat.h:863
#define cfrm_TAG
Definition: 4xm.c:49
#define FOURXMV_TAG
Definition: 4xm.c:36
int id
format-specific stream ID
Definition: avformat.h:622
#define AV_WL32(p, d)
Definition: intreadwrite.h:255
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1387
static int read_header(FFV1Context *f)
Definition: ffv1.c:1513
#define vtrk_SIZE
Definition: 4xm.c:55
#define strk_TAG
Definition: 4xm.c:46
uint8_t * data
Definition: avcodec.h:908
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:151
Definition: 4xm.c:65
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:140
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:269
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:492
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1974
AVInputFormat ff_fourxm_demuxer
Definition: 4xm.c:351
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:652
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:137
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:738
#define AVERROR(e)
Definition: error.h:43
#define RIFF_TAG
Definition: 4xm.c:35
int video_stream_index
Definition: 4xm.c:77
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:191
AV_RL32
Definition: bytestream.h:89
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:140
AVStream * avformat_new_stream(AVFormatContext *s, AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2776
AVCodecContext * codec
codec context
Definition: avformat.h:623
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:341
int bit_rate
the average bitrate
Definition: avcodec.h:1340
static int fourxm_read_close(AVFormatContext *s)
Definition: 4xm.c:342
int stream_index
Definition: 4xm.c:69
int64_t video_pts
Definition: 4xm.c:81
int track_count
Definition: 4xm.c:78
int width
picture width / height.
Definition: avcodec.h:1408
#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:483
static int read_probe(AVProbeData *p)
Definition: img2.c:185
AudioTrack * tracks
Definition: 4xm.c:79
#define MOVI_TAG
Definition: 4xm.c:40
static int fourxm_read_header(AVFormatContext *s, AVFormatParameters *ap)
Definition: 4xm.c:94
Stream structure.
Definition: avformat.h:620
NULL
Definition: eval.c:50
enum AVMediaType codec_type
Definition: avcodec.h:1574
int sample_rate
samples per second
Definition: avcodec.h:1456
AVIOContext * pb
Definition: avformat.h:896
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:111
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1590
#define LIST_TAG
Definition: 4xm.c:37
int extradata_size
Definition: avcodec.h:1388
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:109
#define std__TAG
Definition: 4xm.c:43
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:64
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:339
#define snd__TAG
Definition: 4xm.c:53
#define AVPROBE_SCORE_MAX
maximum score, half of that is used for file-extension-based detection
Definition: avformat.h:345
Main libavformat public API header.
#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:98
int channels
number of audio channels
Definition: avcodec.h:1457
void * priv_data
Format private data.
Definition: avformat.h:883
#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:460
int stream_index
Definition: avcodec.h:910
#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:901
float fps
Definition: 4xm.c:82
enum CodecID codec_id
Definition: avcodec.h:1575