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 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 
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;
60  int sample_rate;
61  int audio_stream_index;
62  int video_stream_index;
63 } WsVqaDemuxContext;
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 
79 static int wsvqa_read_header(AVFormatContext *s)
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;
96  st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
97  st->codec->codec_id = AV_CODEC_ID_WS_VQA;
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  st->codec->extradata_size = VQA_HEADER_SIZE;
105  st->codec->extradata = av_mallocz(VQA_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
106  header = (unsigned char *)st->codec->extradata;
107  if (avio_read(pb, st->codec->extradata, VQA_HEADER_SIZE) !=
108  VQA_HEADER_SIZE) {
109  av_free(st->codec->extradata);
110  return AVERROR(EIO);
111  }
112  st->codec->width = AV_RL16(&header[6]);
113  st->codec->height = AV_RL16(&header[8]);
114  fps = header[12];
115  st->nb_frames =
116  st->duration = AV_RL16(&header[4]);
117  if (fps < 1 || fps > 30) {
118  av_log(s, AV_LOG_ERROR, "invalid fps: %d\n", fps);
119  return AVERROR_INVALIDDATA;
120  }
121  avpriv_set_pts_info(st, 64, 1, fps);
122 
123  wsvqa->version = AV_RL16(&header[ 0]);
124  wsvqa->sample_rate = AV_RL16(&header[24]);
125  wsvqa->channels = header[26];
126  wsvqa->bps = header[27];
127  wsvqa->audio_stream_index = -1;
128 
129  s->ctx_flags |= AVFMTCTX_NOHEADER;
130 
131  /* there are 0 or more chunks before the FINF chunk; iterate until
132  * FINF has been skipped and the file will be ready to be demuxed */
133  do {
134  if (avio_read(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE) {
135  av_free(st->codec->extradata);
136  return AVERROR(EIO);
137  }
138  chunk_tag = AV_RB32(&scratch[0]);
139  chunk_size = AV_RB32(&scratch[4]);
140 
141  /* catch any unknown header tags, for curiousity */
142  switch (chunk_tag) {
143  case CINF_TAG:
144  case CINH_TAG:
145  case CIND_TAG:
146  case PINF_TAG:
147  case PINH_TAG:
148  case PIND_TAG:
149  case FINF_TAG:
150  case CMDS_TAG:
151  break;
152 
153  default:
154  av_log (s, AV_LOG_ERROR, " note: unknown chunk seen (%c%c%c%c)\n",
155  scratch[0], scratch[1],
156  scratch[2], scratch[3]);
157  break;
158  }
159 
160  avio_skip(pb, chunk_size);
161  } while (chunk_tag != FINF_TAG);
162 
163  return 0;
164 }
165 
166 static int wsvqa_read_packet(AVFormatContext *s,
167  AVPacket *pkt)
168 {
169  WsVqaDemuxContext *wsvqa = s->priv_data;
170  AVIOContext *pb = s->pb;
171  int ret = -1;
172  unsigned char preamble[VQA_PREAMBLE_SIZE];
173  unsigned int chunk_type;
174  unsigned int chunk_size;
175  int skip_byte;
176 
177  while (avio_read(pb, preamble, VQA_PREAMBLE_SIZE) == VQA_PREAMBLE_SIZE) {
178  chunk_type = AV_RB32(&preamble[0]);
179  chunk_size = AV_RB32(&preamble[4]);
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  if (av_new_packet(pkt, chunk_size))
186  return AVERROR(EIO);
187  ret = avio_read(pb, pkt->data, chunk_size);
188  if (ret != chunk_size) {
189  av_free_packet(pkt);
190  return AVERROR(EIO);
191  }
192 
193  switch (chunk_type) {
194  case SND0_TAG:
195  case SND1_TAG:
196  case SND2_TAG:
197  if (wsvqa->audio_stream_index == -1) {
198  AVStream *st = avformat_new_stream(s, NULL);
199  if (!st)
200  return AVERROR(ENOMEM);
201 
202  wsvqa->audio_stream_index = st->index;
203  if (!wsvqa->sample_rate)
204  wsvqa->sample_rate = 22050;
205  if (!wsvqa->channels)
206  wsvqa->channels = 1;
207  if (!wsvqa->bps)
208  wsvqa->bps = 8;
209  st->codec->sample_rate = wsvqa->sample_rate;
210  st->codec->bits_per_coded_sample = wsvqa->bps;
211  st->codec->channels = wsvqa->channels;
212  st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
213 
214  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
215 
216  switch (chunk_type) {
217  case SND0_TAG:
218  if (wsvqa->bps == 16)
219  st->codec->codec_id = AV_CODEC_ID_PCM_S16LE;
220  else
221  st->codec->codec_id = AV_CODEC_ID_PCM_U8;
222  break;
223  case SND1_TAG:
224  st->codec->codec_id = AV_CODEC_ID_WESTWOOD_SND1;
225  break;
226  case SND2_TAG:
227  st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_WS;
228  st->codec->extradata_size = 2;
229  st->codec->extradata = av_mallocz(2 + FF_INPUT_BUFFER_PADDING_SIZE);
230  if (!st->codec->extradata)
231  return AVERROR(ENOMEM);
232  AV_WL16(st->codec->extradata, wsvqa->version);
233  break;
234  }
235  }
236 
237  pkt->stream_index = wsvqa->audio_stream_index;
238  switch (chunk_type) {
239  case SND1_TAG:
240  /* unpacked size is stored in header */
241  pkt->duration = AV_RL16(pkt->data) / wsvqa->channels;
242  break;
243  case SND2_TAG:
244  /* 2 samples/byte, 1 or 2 samples per frame depending on stereo */
245  pkt->duration = (chunk_size * 2) / wsvqa->channels;
246  break;
247  }
248  break;
249  case VQFR_TAG:
250  pkt->stream_index = wsvqa->video_stream_index;
251  pkt->duration = 1;
252  break;
253  }
254 
255  /* stay on 16-bit alignment */
256  if (skip_byte)
257  avio_skip(pb, 1);
258 
259  return ret;
260  } else {
261  switch(chunk_type){
262  case CMDS_TAG:
263  break;
264  default:
265  av_log(s, AV_LOG_INFO, "Skipping unknown chunk 0x%08X\n", chunk_type);
266  }
267  avio_skip(pb, chunk_size + skip_byte);
268  }
269  }
270 
271  return ret;
272 }
273 
274 AVInputFormat ff_wsvqa_demuxer = {
275  .name = "wsvqa",
276  .long_name = NULL_IF_CONFIG_SMALL("Westwood Studios VQA"),
277  .priv_data_size = sizeof(WsVqaDemuxContext),
278  .read_probe = wsvqa_probe,
279  .read_header = wsvqa_read_header,
280  .read_packet = wsvqa_read_packet,
281 };