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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  unsigned char *header;
85  unsigned char scratch[VQA_PREAMBLE_SIZE];
86  unsigned int chunk_tag;
87  unsigned int 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  if (!st->codec->extradata)
106  return AVERROR(ENOMEM);
108  header = (unsigned char *)st->codec->extradata;
110  VQA_HEADER_SIZE) {
111  return AVERROR(EIO);
112  }
113  st->codec->width = AV_RL16(&header[6]);
114  st->codec->height = AV_RL16(&header[8]);
115  fps = header[12];
116  st->nb_frames =
117  st->duration = AV_RL16(&header[4]);
118  if (fps < 1 || fps > 30) {
119  av_log(s, AV_LOG_ERROR, "invalid fps: %d\n", fps);
120  return AVERROR_INVALIDDATA;
121  }
122  avpriv_set_pts_info(st, 64, 1, fps);
123 
124  wsvqa->version = AV_RL16(&header[ 0]);
125  wsvqa->sample_rate = AV_RL16(&header[24]);
126  wsvqa->channels = header[26];
127  wsvqa->bps = header[27];
128  wsvqa->audio_stream_index = -1;
129 
131 
132  /* there are 0 or more chunks before the FINF chunk; iterate until
133  * FINF has been skipped and the file will be ready to be demuxed */
134  do {
135  if (avio_read(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE)
136  return AVERROR(EIO);
137  chunk_tag = AV_RB32(&scratch[0]);
138  chunk_size = AV_RB32(&scratch[4]);
139 
140  /* catch any unknown header tags, for curiousity */
141  switch (chunk_tag) {
142  case CINF_TAG:
143  case CINH_TAG:
144  case CIND_TAG:
145  case PINF_TAG:
146  case PINH_TAG:
147  case PIND_TAG:
148  case FINF_TAG:
149  case CMDS_TAG:
150  break;
151 
152  default:
153  av_log (s, AV_LOG_ERROR, " note: unknown chunk seen (%c%c%c%c)\n",
154  scratch[0], scratch[1],
155  scratch[2], scratch[3]);
156  break;
157  }
158 
159  avio_skip(pb, chunk_size);
160  } while (chunk_tag != FINF_TAG);
161 
162  return 0;
163 }
164 
166  AVPacket *pkt)
167 {
168  WsVqaDemuxContext *wsvqa = s->priv_data;
169  AVIOContext *pb = s->pb;
170  int ret = -1;
171  unsigned char preamble[VQA_PREAMBLE_SIZE];
172  unsigned int chunk_type;
173  unsigned int chunk_size;
174  int skip_byte;
175 
176  while (avio_read(pb, preamble, VQA_PREAMBLE_SIZE) == VQA_PREAMBLE_SIZE) {
177  chunk_type = AV_RB32(&preamble[0]);
178  chunk_size = AV_RB32(&preamble[4]);
179 
180  skip_byte = chunk_size & 0x01;
181 
182  if ((chunk_type == SND0_TAG) || (chunk_type == SND1_TAG) ||
183  (chunk_type == SND2_TAG) || (chunk_type == VQFR_TAG)) {
184 
185  ret= av_get_packet(pb, pkt, chunk_size);
186  if (ret<0)
187  return AVERROR(EIO);
188 
189  switch (chunk_type) {
190  case SND0_TAG:
191  case SND1_TAG:
192  case SND2_TAG:
193  if (wsvqa->audio_stream_index == -1) {
194  AVStream *st = avformat_new_stream(s, NULL);
195  if (!st)
196  return AVERROR(ENOMEM);
197 
198  wsvqa->audio_stream_index = st->index;
199  if (!wsvqa->sample_rate)
200  wsvqa->sample_rate = 22050;
201  if (!wsvqa->channels)
202  wsvqa->channels = 1;
203  if (!wsvqa->bps)
204  wsvqa->bps = 8;
205  st->codec->sample_rate = wsvqa->sample_rate;
206  st->codec->bits_per_coded_sample = wsvqa->bps;
207  st->codec->channels = wsvqa->channels;
209 
210  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
211 
212  switch (chunk_type) {
213  case SND0_TAG:
214  if (wsvqa->bps == 16)
216  else
218  break;
219  case SND1_TAG:
221  break;
222  case SND2_TAG:
224  st->codec->extradata_size = 2;
226  if (!st->codec->extradata)
227  return AVERROR(ENOMEM);
228  AV_WL16(st->codec->extradata, wsvqa->version);
229  break;
230  }
231  }
232 
233  pkt->stream_index = wsvqa->audio_stream_index;
234  switch (chunk_type) {
235  case SND1_TAG:
236  /* unpacked size is stored in header */
237  if(pkt->data)
238  pkt->duration = AV_RL16(pkt->data) / wsvqa->channels;
239  break;
240  case SND2_TAG:
241  /* 2 samples/byte, 1 or 2 samples per frame depending on stereo */
242  pkt->duration = (chunk_size * 2) / wsvqa->channels;
243  break;
244  }
245  break;
246  case VQFR_TAG:
247  pkt->stream_index = wsvqa->video_stream_index;
248  pkt->duration = 1;
249  break;
250  }
251 
252  /* stay on 16-bit alignment */
253  if (skip_byte)
254  avio_skip(pb, 1);
255 
256  return ret;
257  } else {
258  switch(chunk_type){
259  case CMDS_TAG:
260  break;
261  default:
262  av_log(s, AV_LOG_INFO, "Skipping unknown chunk 0x%08X\n", chunk_type);
263  }
264  avio_skip(pb, chunk_size + skip_byte);
265  }
266  }
267 
268  return ret;
269 }
270 
272  .name = "wsvqa",
273  .long_name = NULL_IF_CONFIG_SMALL("Westwood Studios VQA"),
274  .priv_data_size = sizeof(WsVqaDemuxContext),
278 };