FFmpeg  2.1.1
westwood_vqa.c
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1 /*
2  * Westwood Studios VQA Format Demuxer
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  * Westwood Studios VQA file demuxer
25  * by Mike Melanson (melanson@pcisys.net)
26  * for more information on the Westwood file formats, visit:
27  * http://www.pcisys.net/~melanson/codecs/
28  * http://www.geocities.com/SiliconValley/8682/aud3.txt
29  */
30 
31 #include "libavutil/intreadwrite.h"
32 #include "avformat.h"
33 #include "internal.h"
34 
35 #define FORM_TAG MKBETAG('F', 'O', 'R', 'M')
36 #define WVQA_TAG MKBETAG('W', 'V', 'Q', 'A')
37 #define VQHD_TAG MKBETAG('V', 'Q', 'H', 'D')
38 #define FINF_TAG MKBETAG('F', 'I', 'N', 'F')
39 #define SND0_TAG MKBETAG('S', 'N', 'D', '0')
40 #define SND1_TAG MKBETAG('S', 'N', 'D', '1')
41 #define SND2_TAG MKBETAG('S', 'N', 'D', '2')
42 #define VQFR_TAG MKBETAG('V', 'Q', 'F', 'R')
43 
44 /* don't know what these tags are for, but acknowledge their existence */
45 #define CINF_TAG MKBETAG('C', 'I', 'N', 'F')
46 #define CINH_TAG MKBETAG('C', 'I', 'N', 'H')
47 #define CIND_TAG MKBETAG('C', 'I', 'N', 'D')
48 #define PINF_TAG MKBETAG('P', 'I', 'N', 'F')
49 #define PINH_TAG MKBETAG('P', 'I', 'N', 'H')
50 #define PIND_TAG MKBETAG('P', 'I', 'N', 'D')
51 #define CMDS_TAG MKBETAG('C', 'M', 'D', 'S')
52 
53 #define VQA_HEADER_SIZE 0x2A
54 #define VQA_PREAMBLE_SIZE 8
55 
56 typedef struct WsVqaDemuxContext {
57  int version;
58  int bps;
59  int channels;
64 
65 static int wsvqa_probe(AVProbeData *p)
66 {
67  /* need 12 bytes to qualify */
68  if (p->buf_size < 12)
69  return 0;
70 
71  /* check for the VQA signatures */
72  if ((AV_RB32(&p->buf[0]) != FORM_TAG) ||
73  (AV_RB32(&p->buf[8]) != WVQA_TAG))
74  return 0;
75 
76  return AVPROBE_SCORE_MAX;
77 }
78 
80 {
81  WsVqaDemuxContext *wsvqa = s->priv_data;
82  AVIOContext *pb = s->pb;
83  AVStream *st;
84  uint8_t *header;
85  uint8_t scratch[VQA_PREAMBLE_SIZE];
86  uint32_t chunk_tag;
87  uint32_t chunk_size;
88  int fps;
89 
90  /* initialize the video decoder stream */
91  st = avformat_new_stream(s, NULL);
92  if (!st)
93  return AVERROR(ENOMEM);
94  st->start_time = 0;
95  wsvqa->video_stream_index = st->index;
98  st->codec->codec_tag = 0; /* no fourcc */
99 
100  /* skip to the start of the VQA header */
101  avio_seek(pb, 20, SEEK_SET);
102 
103  /* the VQA header needs to go to the decoder */
105  return AVERROR(ENOMEM);
106  header = (uint8_t *)st->codec->extradata;
108  VQA_HEADER_SIZE) {
109  return AVERROR(EIO);
110  }
111  st->codec->width = AV_RL16(&header[6]);
112  st->codec->height = AV_RL16(&header[8]);
113  fps = header[12];
114  st->nb_frames =
115  st->duration = AV_RL16(&header[4]);
116  if (fps < 1 || fps > 30) {
117  av_log(s, AV_LOG_ERROR, "invalid fps: %d\n", fps);
118  return AVERROR_INVALIDDATA;
119  }
120  avpriv_set_pts_info(st, 64, 1, fps);
121 
122  wsvqa->version = AV_RL16(&header[ 0]);
123  wsvqa->sample_rate = AV_RL16(&header[24]);
124  wsvqa->channels = header[26];
125  wsvqa->bps = header[27];
126  wsvqa->audio_stream_index = -1;
127 
129 
130  /* there are 0 or more chunks before the FINF chunk; iterate until
131  * FINF has been skipped and the file will be ready to be demuxed */
132  do {
133  if (avio_read(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE)
134  return AVERROR(EIO);
135  chunk_tag = AV_RB32(&scratch[0]);
136  chunk_size = AV_RB32(&scratch[4]);
137 
138  /* catch any unknown header tags, for curiousity */
139  switch (chunk_tag) {
140  case CINF_TAG:
141  case CINH_TAG:
142  case CIND_TAG:
143  case PINF_TAG:
144  case PINH_TAG:
145  case PIND_TAG:
146  case FINF_TAG:
147  case CMDS_TAG:
148  break;
149 
150  default:
151  av_log (s, AV_LOG_ERROR, " note: unknown chunk seen (%c%c%c%c)\n",
152  scratch[0], scratch[1],
153  scratch[2], scratch[3]);
154  break;
155  }
156 
157  avio_skip(pb, chunk_size);
158  } while (chunk_tag != FINF_TAG);
159 
160  return 0;
161 }
162 
164  AVPacket *pkt)
165 {
166  WsVqaDemuxContext *wsvqa = s->priv_data;
167  AVIOContext *pb = s->pb;
168  int ret = -1;
169  uint8_t preamble[VQA_PREAMBLE_SIZE];
170  uint32_t chunk_type;
171  uint32_t chunk_size;
172  int skip_byte;
173 
174  while (avio_read(pb, preamble, VQA_PREAMBLE_SIZE) == VQA_PREAMBLE_SIZE) {
175  chunk_type = AV_RB32(&preamble[0]);
176  chunk_size = AV_RB32(&preamble[4]);
177 
178  skip_byte = chunk_size & 0x01;
179 
180  if ((chunk_type == SND0_TAG) || (chunk_type == SND1_TAG) ||
181  (chunk_type == SND2_TAG) || (chunk_type == VQFR_TAG)) {
182 
183  ret= av_get_packet(pb, pkt, chunk_size);
184  if (ret<0)
185  return AVERROR(EIO);
186 
187  switch (chunk_type) {
188  case SND0_TAG:
189  case SND1_TAG:
190  case SND2_TAG:
191  if (wsvqa->audio_stream_index == -1) {
192  AVStream *st = avformat_new_stream(s, NULL);
193  if (!st)
194  return AVERROR(ENOMEM);
195 
196  wsvqa->audio_stream_index = st->index;
197  if (!wsvqa->sample_rate)
198  wsvqa->sample_rate = 22050;
199  if (!wsvqa->channels)
200  wsvqa->channels = 1;
201  if (!wsvqa->bps)
202  wsvqa->bps = 8;
203  st->codec->sample_rate = wsvqa->sample_rate;
204  st->codec->bits_per_coded_sample = wsvqa->bps;
205  st->codec->channels = wsvqa->channels;
207 
208  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
209 
210  switch (chunk_type) {
211  case SND0_TAG:
212  if (wsvqa->bps == 16)
214  else
216  break;
217  case SND1_TAG:
219  break;
220  case SND2_TAG:
222  if (ff_alloc_extradata(st->codec, 2))
223  return AVERROR(ENOMEM);
224  AV_WL16(st->codec->extradata, wsvqa->version);
225  break;
226  }
227  }
228 
229  pkt->stream_index = wsvqa->audio_stream_index;
230  switch (chunk_type) {
231  case SND1_TAG:
232  /* unpacked size is stored in header */
233  if(pkt->data)
234  pkt->duration = AV_RL16(pkt->data) / wsvqa->channels;
235  break;
236  case SND2_TAG:
237  /* 2 samples/byte, 1 or 2 samples per frame depending on stereo */
238  pkt->duration = (chunk_size * 2) / wsvqa->channels;
239  break;
240  }
241  break;
242  case VQFR_TAG:
243  pkt->stream_index = wsvqa->video_stream_index;
244  pkt->duration = 1;
245  break;
246  }
247 
248  /* stay on 16-bit alignment */
249  if (skip_byte)
250  avio_skip(pb, 1);
251 
252  return ret;
253  } else {
254  switch(chunk_type){
255  case CMDS_TAG:
256  break;
257  default:
258  av_log(s, AV_LOG_INFO, "Skipping unknown chunk 0x%08X\n", chunk_type);
259  }
260  avio_skip(pb, chunk_size + skip_byte);
261  }
262  }
263 
264  return ret;
265 }
266 
268  .name = "wsvqa",
269  .long_name = NULL_IF_CONFIG_SMALL("Westwood Studios VQA"),
270  .priv_data_size = sizeof(WsVqaDemuxContext),
274 };
const char * s
Definition: avisynth_c.h:668
Bytestream IO Context.
Definition: avio.h:68
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:478
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:3922
#define AV_RL16(x)
Definition: intreadwrite.h:245
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:686
int index
stream index in AVFormatContext
Definition: avformat.h:668
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
#define PIND_TAG
Definition: westwood_vqa.c:50
static int wsvqa_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: westwood_vqa.c:163
int ctx_flags
Format-specific flags, see AVFMTCTX_xx.
Definition: avformat.h:1004
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1254
if((e=av_dict_get(options,"", NULL, AV_DICT_IGNORE_SUFFIX)))
Definition: avfilter.c:965
Format I/O context.
Definition: avformat.h:968
uint8_t
#define FORM_TAG
Definition: westwood_vqa.c:35
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:336
#define CMDS_TAG
Definition: westwood_vqa.c:51
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2563
#define CINH_TAG
Definition: westwood_vqa.c:46
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3348
int duration
Duration of this packet in AVStream-&gt;time_base units, 0 if unknown.
Definition: avcodec.h:1085
#define VQFR_TAG
Definition: westwood_vqa.c:42
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:200
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: avcodec.h:4147
void * priv_data
Format private data.
Definition: avformat.h:988
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
#define PINH_TAG
Definition: westwood_vqa.c:49
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:337
#define SND0_TAG
Definition: westwood_vqa.c:39
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:54
ret
Definition: avfilter.c:961
int width
picture width / height.
Definition: avcodec.h:1314
#define SND2_TAG
Definition: westwood_vqa.c:41
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:199
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:592
Stream structure.
Definition: avformat.h:667
#define WVQA_TAG
Definition: westwood_vqa.c:36
#define AV_WL16(p, darg)
Definition: intreadwrite.h:250
#define FINF_TAG
Definition: westwood_vqa.c:38
#define VQA_PREAMBLE_SIZE
Definition: westwood_vqa.c:54
#define AV_LOG_INFO
Standard information.
Definition: avcodec.h:4158
#define CINF_TAG
Definition: westwood_vqa.c:45
enum AVMediaType codec_type
Definition: avcodec.h:1154
enum AVCodecID codec_id
Definition: avcodec.h:1157
int sample_rate
samples per second
Definition: avcodec.h:1873
static int wsvqa_probe(AVProbeData *p)
Definition: westwood_vqa.c:65
#define AVFMTCTX_NOHEADER
signal that no header is present (streams are added dynamically)
Definition: avformat.h:938
unsigned int codec_tag
fourcc (LSB first, so &quot;ABCD&quot; -&gt; (&#39;D&#39;&lt;&lt;24) + (&#39;C&#39;&lt;&lt;16) + (&#39;B&#39;&lt;&lt;8) + &#39;A&#39;).
Definition: avcodec.h:1172
int ff_alloc_extradata(AVCodecContext *avctx, int size)
Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:2690
AVIOContext * pb
I/O context.
Definition: avformat.h:1001
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
AVInputFormat ff_wsvqa_demuxer
Definition: westwood_vqa.c:267
uint8_t * data
Definition: avcodec.h:1063
#define VQA_HEADER_SIZE
Definition: westwood_vqa.c:53
This structure contains the data a format has to probe a file.
Definition: avformat.h:334
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:256
#define PINF_TAG
Definition: westwood_vqa.c:48
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:342
static int wsvqa_read_header(AVFormatContext *s)
Definition: westwood_vqa.c:79
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:720
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:480
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:713
#define CIND_TAG
Definition: westwood_vqa.c:47
Main libavformat public API header.
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:722
#define AV_RB32(x)
Definition: intreadwrite.h:258
#define AVERROR_INVALIDDATA
int channels
number of audio channels
Definition: avcodec.h:1874
#define AVERROR(e)
#define SND1_TAG
Definition: westwood_vqa.c:40
static AVPacket pkt
Definition: demuxing.c:52
int stream_index
Definition: avcodec.h:1065
This structure stores compressed data.
Definition: avcodec.h:1040