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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  ret = AVERROR_INVALIDDATA; \
63  goto fail; \
64  } \
65  fourcc_tag = avio_rl32(pb);
66 
67 typedef struct AudioTrack {
69  int bits;
70  int channels;
72  int adpcm;
73  int64_t audio_pts;
74 } AudioTrack;
75 
76 typedef struct FourxmDemuxContext {
80 
81  int64_t video_pts;
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 
95  FourxmDemuxContext *fourxm, uint8_t *buf, int size,
96  int left)
97 {
98  AVStream *st;
99  /* check that there is enough data */
100  if (size != vtrk_SIZE || left < size + 8) {
101  return AVERROR_INVALIDDATA;
102  }
103 
104  /* allocate a new AVStream */
105  st = avformat_new_stream(s, NULL);
106  if (!st)
107  return AVERROR(ENOMEM);
108 
109  avpriv_set_pts_info(st, 60, fourxm->fps.den, fourxm->fps.num);
110 
111  fourxm->video_stream_index = st->index;
112 
115 
117  if (!st->codec->extradata)
118  return AVERROR(ENOMEM);
119  st->codec->extradata_size = 4;
120  AV_WL32(st->codec->extradata, AV_RL32(buf + 16));
121  st->codec->width = AV_RL32(buf + 36);
122  st->codec->height = AV_RL32(buf + 40);
123 
124  return 0;
125 }
126 
127 
129  FourxmDemuxContext *fourxm, uint8_t *buf, int size,
130  int left)
131 {
132  AVStream *st;
133  int track;
134  /* check that there is enough data */
135  if (size != strk_SIZE || left < size + 8)
136  return AVERROR_INVALIDDATA;
137 
138  track = AV_RL32(buf + 8);
139  if ((unsigned)track >= UINT_MAX / sizeof(AudioTrack) - 1) {
140  av_log(s, AV_LOG_ERROR, "current_track too large\n");
141  return AVERROR_INVALIDDATA;
142  }
143 
144  if (track + 1 > fourxm->track_count) {
145  if (av_reallocp_array(&fourxm->tracks, track + 1, sizeof(AudioTrack)))
146  return AVERROR(ENOMEM);
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  if (!fourxm->tracks[track].adpcm && fourxm->tracks[track].bits<8) {
164  av_log(s, AV_LOG_ERROR, "bits unspecified for non ADPCM\n");
165  return AVERROR_INVALIDDATA;
166  }
167 
168  /* allocate a new AVStream */
169  st = avformat_new_stream(s, NULL);
170  if (!st)
171  return AVERROR(ENOMEM);
172 
173  st->id = track;
174  avpriv_set_pts_info(st, 60, 1, fourxm->tracks[track].sample_rate);
175 
176  fourxm->tracks[track].stream_index = st->index;
177 
179  st->codec->codec_tag = 0;
180  st->codec->channels = fourxm->tracks[track].channels;
181  st->codec->sample_rate = fourxm->tracks[track].sample_rate;
182  st->codec->bits_per_coded_sample = fourxm->tracks[track].bits;
183  st->codec->bit_rate = st->codec->channels *
184  st->codec->sample_rate *
186  st->codec->block_align = st->codec->channels *
188 
189  if (fourxm->tracks[track].adpcm){
191  } else if (st->codec->bits_per_coded_sample == 8) {
193  } else
195 
196  return 0;
197 }
198 
200 {
201  AVIOContext *pb = s->pb;
202  unsigned int fourcc_tag;
203  unsigned int size;
204  int header_size;
205  FourxmDemuxContext *fourxm = s->priv_data;
206  unsigned char *header = NULL;
207  int i, ret;
208 
209  fourxm->track_count = 0;
210  fourxm->tracks = NULL;
211  fourxm->fps = (AVRational){1,1};
212  fourxm->video_stream_index = -1;
213 
214  /* skip the first 3 32-bit numbers */
215  avio_skip(pb, 12);
216 
217  /* check for LIST-HEAD */
218  GET_LIST_HEADER();
219  header_size = size - 4;
220  if (fourcc_tag != HEAD_TAG || header_size < 0)
221  return AVERROR_INVALIDDATA;
222 
223  /* allocate space for the header and load the whole thing */
224  header = av_malloc(header_size);
225  if (!header)
226  return AVERROR(ENOMEM);
227  if (avio_read(pb, header, header_size) != header_size) {
228  av_free(header);
229  return AVERROR(EIO);
230  }
231 
232  /* take the lazy approach and search for any and all vtrk and strk chunks */
233  for (i = 0; i < header_size - 8; i++) {
234  fourcc_tag = AV_RL32(&header[i]);
235  size = AV_RL32(&header[i + 4]);
236  if (size > header_size - i - 8 && (fourcc_tag == vtrk_TAG || fourcc_tag == strk_TAG)) {
237  av_log(s, AV_LOG_ERROR, "chunk larger than array %d>%d\n", size, header_size - i - 8);
238  return AVERROR_INVALIDDATA;
239  }
240 
241  if (fourcc_tag == std__TAG) {
242  if (header_size - i < 16) {
243  av_log(s, AV_LOG_ERROR, "std TAG truncated\n");
244  ret = AVERROR_INVALIDDATA;
245  goto fail;
246  }
247  fourxm->fps = av_d2q(av_int2float(AV_RL32(&header[i + 12])), 10000);
248  } else if (fourcc_tag == vtrk_TAG) {
249  if ((ret = parse_vtrk(s, fourxm, header + i, size,
250  header_size - i)) < 0)
251  goto fail;
252 
253  i += 8 + size;
254  } else if (fourcc_tag == strk_TAG) {
255  if ((ret = parse_strk(s, fourxm, header + i, size,
256  header_size - i)) < 0)
257  goto fail;
258 
259  i += 8 + size;
260  }
261  }
262 
263  /* skip over the LIST-MOVI chunk (which is where the stream should be */
264  GET_LIST_HEADER();
265  if (fourcc_tag != MOVI_TAG) {
266  ret = AVERROR_INVALIDDATA;
267  goto fail;
268  }
269 
270  av_free(header);
271  /* initialize context members */
272  fourxm->video_pts = -1; /* first frame will push to 0 */
273 
274  return 0;
275 fail:
276  av_freep(&fourxm->tracks);
277  av_free(header);
278  return ret;
279 }
280 
282  AVPacket *pkt)
283 {
284  FourxmDemuxContext *fourxm = s->priv_data;
285  AVIOContext *pb = s->pb;
286  unsigned int fourcc_tag;
287  unsigned int size;
288  int ret = 0;
289  unsigned int track_number;
290  int packet_read = 0;
291  unsigned char header[8];
292  int audio_frame_count;
293 
294  while (!packet_read) {
295  if ((ret = avio_read(s->pb, header, 8)) < 0)
296  return ret;
297  fourcc_tag = AV_RL32(&header[0]);
298  size = AV_RL32(&header[4]);
299  if (avio_feof(pb))
300  return AVERROR(EIO);
301  switch (fourcc_tag) {
302  case LIST_TAG:
303  /* this is a good time to bump the video pts */
304  fourxm->video_pts++;
305 
306  /* skip the LIST-* tag and move on to the next fourcc */
307  avio_rl32(pb);
308  break;
309 
310  case ifrm_TAG:
311  case pfrm_TAG:
312  case cfrm_TAG:
313  case ifr2_TAG:
314  case pfr2_TAG:
315  case cfr2_TAG:
316  /* allocate 8 more bytes than 'size' to account for fourcc
317  * and size */
318  if (fourxm->video_stream_index < 0)
319  return AVERROR_INVALIDDATA;
320  if (size + 8 < size || av_new_packet(pkt, size + 8))
321  return AVERROR(EIO);
322  pkt->stream_index = fourxm->video_stream_index;
323  pkt->pts = fourxm->video_pts;
324  pkt->pos = avio_tell(s->pb);
325  memcpy(pkt->data, header, 8);
326  ret = avio_read(s->pb, &pkt->data[8], size);
327 
328  if (ret < 0) {
329  av_free_packet(pkt);
330  } else {
331  packet_read = 1;
332  av_shrink_packet(pkt, ret + 8);
333  }
334  break;
335 
336  case snd__TAG:
337  track_number = avio_rl32(pb);
338  avio_skip(pb, 4);
339  size -= 8;
340 
341  if (track_number < fourxm->track_count &&
342  fourxm->tracks[track_number].channels > 0) {
343  ret = av_get_packet(s->pb, pkt, size);
344  if (ret < 0)
345  return AVERROR(EIO);
346  pkt->stream_index =
347  fourxm->tracks[track_number].stream_index;
348  pkt->pts = fourxm->tracks[track_number].audio_pts;
349  packet_read = 1;
350 
351  /* pts accounting */
352  audio_frame_count = size;
353  if (fourxm->tracks[track_number].adpcm)
354  audio_frame_count -= 2 * (fourxm->tracks[track_number].channels);
355  audio_frame_count /= fourxm->tracks[track_number].channels;
356  if (fourxm->tracks[track_number].adpcm) {
357  audio_frame_count *= 2;
358  } else
359  audio_frame_count /=
360  (fourxm->tracks[track_number].bits / 8);
361  fourxm->tracks[track_number].audio_pts += audio_frame_count;
362  } else {
363  avio_skip(pb, size);
364  }
365  break;
366 
367  default:
368  avio_skip(pb, size);
369  break;
370  }
371  }
372  return ret;
373 }
374 
376 {
377  FourxmDemuxContext *fourxm = s->priv_data;
378 
379  av_freep(&fourxm->tracks);
380 
381  return 0;
382 }
383 
385  .name = "4xm",
386  .long_name = NULL_IF_CONFIG_SMALL("4X Technologies"),
387  .priv_data_size = sizeof(FourxmDemuxContext),
392 };
#define NULL
Definition: coverity.c:32
int sample_rate
Definition: 4xm.c:68
const char * s
Definition: avisynth_c.h:631
Bytestream IO Context.
Definition: avio.h:111
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:284
static int fourxm_probe(AVProbeData *p)
Definition: 4xm.c:85
int64_t audio_pts
Definition: 4xm.c:73
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1458
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:104
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:4098
#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 num
numerator
Definition: rational.h:44
int index
stream index in AVFormatContext
Definition: avformat.h:855
static int audio_frame_count
#define strk_SIZE
Definition: 4xm.c:56
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:279
static int parse_vtrk(AVFormatContext *s, FourxmDemuxContext *fourxm, uint8_t *buf, int size, int left)
Definition: 4xm.c:94
int channels
Definition: 4xm.c:70
static AVPacket pkt
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:2309
AVRational fps
Definition: 4xm.c:82
static int fourxm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: 4xm.c:281
int adpcm
Definition: 4xm.c:72
Format I/O context.
Definition: avformat.h:1285
#define cfrm_TAG
Definition: 4xm.c:49
uint8_t
#define av_malloc(s)
#define FOURXMV_TAG
Definition: 4xm.c:36
int id
Format-specific stream ID.
Definition: avformat.h:861
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1627
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3761
#define vtrk_SIZE
Definition: 4xm.c:55
#define strk_TAG
Definition: 4xm.c:46
uint8_t * data
Definition: avcodec.h:1433
Definition: 4xm.c:67
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:244
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:390
static const uint8_t header[24]
Definition: sdr2.c:67
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:3006
AVInputFormat ff_fourxm_demuxer
Definition: 4xm.c:384
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:542
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:84
int av_reallocp_array(void *ptr, size_t nmemb, size_t size)
Allocate or reallocate an array through a pointer to a pointer.
Definition: mem.c:215
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:663
#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:178
#define fail()
Definition: checkasm.h:57
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:873
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:462
int bit_rate
the average bitrate
Definition: avcodec.h:1577
static int fourxm_read_close(AVFormatContext *s)
Definition: 4xm.c:375
static int parse_strk(AVFormatContext *s, FourxmDemuxContext *fourxm, uint8_t *buf, int size, int left)
Definition: 4xm.c:128
AVRational av_d2q(double d, int max)
Convert a double precision floating point number to a rational.
Definition: rational.c:106
int stream_index
Definition: 4xm.c:71
int64_t video_pts
Definition: 4xm.c:81
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
int track_count
Definition: 4xm.c:78
int width
picture width / height.
Definition: avcodec.h:1691
#define pfrm_TAG
Definition: 4xm.c:48
AudioTrack * tracks
Definition: 4xm.c:79
#define AV_RL32
Definition: intreadwrite.h:146
#define MOVI_TAG
Definition: 4xm.c:40
static int fourxm_read_header(AVFormatContext *s)
Definition: 4xm.c:199
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:634
Stream structure.
Definition: avformat.h:854
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
enum AVMediaType codec_type
Definition: avcodec.h:1520
enum AVCodecID codec_id
Definition: avcodec.h:1529
int sample_rate
samples per second
Definition: avcodec.h:2272
AVIOContext * pb
I/O context.
Definition: avformat.h:1327
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1544
void * buf
Definition: avisynth_c.h:553
#define LIST_TAG
Definition: 4xm.c:37
int extradata_size
Definition: avcodec.h:1628
#define std__TAG
Definition: 4xm.c:43
rational number numerator/denominator
Definition: rational.h:43
#define ifrm_TAG
Definition: 4xm.c:47
This structure contains the data a format has to probe a file.
Definition: avformat.h:460
#define snd__TAG
Definition: 4xm.c:53
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:472
Main libavformat public API header.
#define vtrk_TAG
Definition: 4xm.c:45
int bits
Definition: 4xm.c:69
int den
denominator
Definition: rational.h:45
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:636
#define GET_LIST_HEADER()
Definition: 4xm.c:58
#define av_free(p)
int channels
number of audio channels
Definition: avcodec.h:2273
void * priv_data
Format private data.
Definition: avformat.h:1313
#define cfr2_TAG
Definition: 4xm.c:52
#define pfr2_TAG
Definition: 4xm.c:51
#define av_freep(p)
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:640
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:303
int stream_index
Definition: avcodec.h:1435
This structure stores compressed data.
Definition: avcodec.h:1410
#define HEAD_TAG
Definition: 4xm.c:38
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:252
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1426
#define AV_WL32(p, v)
Definition: intreadwrite.h:426