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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  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 */
104  if (ff_get_extradata(st->codec, pb, VQA_HEADER_SIZE) < 0)
105  return AVERROR(ENOMEM);
106  header = (uint8_t *)st->codec->extradata;
107  st->codec->width = AV_RL16(&header[6]);
108  st->codec->height = AV_RL16(&header[8]);
109  fps = header[12];
110  st->nb_frames =
111  st->duration = AV_RL16(&header[4]);
112  if (fps < 1 || fps > 30) {
113  av_log(s, AV_LOG_ERROR, "invalid fps: %d\n", fps);
114  return AVERROR_INVALIDDATA;
115  }
116  avpriv_set_pts_info(st, 64, 1, fps);
117 
118  wsvqa->version = AV_RL16(&header[ 0]);
119  wsvqa->sample_rate = AV_RL16(&header[24]);
120  wsvqa->channels = header[26];
121  wsvqa->bps = header[27];
122  wsvqa->audio_stream_index = -1;
123 
125 
126  /* there are 0 or more chunks before the FINF chunk; iterate until
127  * FINF has been skipped and the file will be ready to be demuxed */
128  do {
129  if (avio_read(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE)
130  return AVERROR(EIO);
131  chunk_tag = AV_RB32(&scratch[0]);
132  chunk_size = AV_RB32(&scratch[4]);
133 
134  /* catch any unknown header tags, for curiousity */
135  switch (chunk_tag) {
136  case CINF_TAG:
137  case CINH_TAG:
138  case CIND_TAG:
139  case PINF_TAG:
140  case PINH_TAG:
141  case PIND_TAG:
142  case FINF_TAG:
143  case CMDS_TAG:
144  break;
145 
146  default:
147  av_log (s, AV_LOG_ERROR, " note: unknown chunk seen (%c%c%c%c)\n",
148  scratch[0], scratch[1],
149  scratch[2], scratch[3]);
150  break;
151  }
152 
153  avio_skip(pb, chunk_size);
154  } while (chunk_tag != FINF_TAG);
155 
156  return 0;
157 }
158 
160  AVPacket *pkt)
161 {
162  WsVqaDemuxContext *wsvqa = s->priv_data;
163  AVIOContext *pb = s->pb;
164  int ret = -1;
165  uint8_t preamble[VQA_PREAMBLE_SIZE];
166  uint32_t chunk_type;
167  uint32_t chunk_size;
168  int skip_byte;
169 
170  while (avio_read(pb, preamble, VQA_PREAMBLE_SIZE) == VQA_PREAMBLE_SIZE) {
171  chunk_type = AV_RB32(&preamble[0]);
172  chunk_size = AV_RB32(&preamble[4]);
173 
174  skip_byte = chunk_size & 0x01;
175 
176  if ((chunk_type == SND0_TAG) || (chunk_type == SND1_TAG) ||
177  (chunk_type == SND2_TAG) || (chunk_type == VQFR_TAG)) {
178 
179  ret= av_get_packet(pb, pkt, chunk_size);
180  if (ret<0)
181  return AVERROR(EIO);
182 
183  switch (chunk_type) {
184  case SND0_TAG:
185  case SND1_TAG:
186  case SND2_TAG:
187  if (wsvqa->audio_stream_index == -1) {
188  AVStream *st = avformat_new_stream(s, NULL);
189  if (!st)
190  return AVERROR(ENOMEM);
191 
192  wsvqa->audio_stream_index = st->index;
193  if (!wsvqa->sample_rate)
194  wsvqa->sample_rate = 22050;
195  if (!wsvqa->channels)
196  wsvqa->channels = 1;
197  if (!wsvqa->bps)
198  wsvqa->bps = 8;
199  st->codec->sample_rate = wsvqa->sample_rate;
200  st->codec->bits_per_coded_sample = wsvqa->bps;
201  st->codec->channels = wsvqa->channels;
203 
204  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
205 
206  switch (chunk_type) {
207  case SND0_TAG:
208  if (wsvqa->bps == 16)
210  else
212  break;
213  case SND1_TAG:
215  break;
216  case SND2_TAG:
218  if (ff_alloc_extradata(st->codec, 2))
219  return AVERROR(ENOMEM);
220  AV_WL16(st->codec->extradata, wsvqa->version);
221  break;
222  }
223  }
224 
225  pkt->stream_index = wsvqa->audio_stream_index;
226  switch (chunk_type) {
227  case SND1_TAG:
228  /* unpacked size is stored in header */
229  if(pkt->data)
230  pkt->duration = AV_RL16(pkt->data) / wsvqa->channels;
231  break;
232  case SND2_TAG:
233  /* 2 samples/byte, 1 or 2 samples per frame depending on stereo */
234  pkt->duration = (chunk_size * 2) / wsvqa->channels;
235  break;
236  }
237  break;
238  case VQFR_TAG:
239  pkt->stream_index = wsvqa->video_stream_index;
240  pkt->duration = 1;
241  break;
242  }
243 
244  /* stay on 16-bit alignment */
245  if (skip_byte)
246  avio_skip(pb, 1);
247 
248  return ret;
249  } else {
250  switch(chunk_type){
251  case CMDS_TAG:
252  break;
253  default:
254  av_log(s, AV_LOG_INFO, "Skipping unknown chunk 0x%08X\n", chunk_type);
255  }
256  avio_skip(pb, chunk_size + skip_byte);
257  }
258  }
259 
260  return ret;
261 }
262 
264  .name = "wsvqa",
265  .long_name = NULL_IF_CONFIG_SMALL("Westwood Studios VQA"),
266  .priv_data_size = sizeof(WsVqaDemuxContext),
270 };