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idroqdec.c
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1 /*
2  * id RoQ (.roq) File 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  * id RoQ format file demuxer
25  * by Mike Melanson (melanson@pcisys.net)
26  * for more information on the .roq file format, visit:
27  * http://www.csse.monash.edu.au/~timf/
28  */
29 
31 #include "libavutil/intreadwrite.h"
32 #include "avformat.h"
33 #include "internal.h"
34 #include "avio_internal.h"
35 
36 #define RoQ_MAGIC_NUMBER 0x1084
37 #define RoQ_CHUNK_PREAMBLE_SIZE 8
38 #define RoQ_AUDIO_SAMPLE_RATE 22050
39 #define RoQ_CHUNKS_TO_SCAN 30
40 
41 #define RoQ_INFO 0x1001
42 #define RoQ_QUAD_CODEBOOK 0x1002
43 #define RoQ_QUAD_VQ 0x1011
44 #define RoQ_SOUND_MONO 0x1020
45 #define RoQ_SOUND_STEREO 0x1021
46 
47 typedef struct RoqDemuxContext {
48 
50  int width;
51  int height;
53 
56 
57  int64_t video_pts;
58  unsigned int audio_frame_count;
59 
61 
62 static int roq_probe(AVProbeData *p)
63 {
64  if ((AV_RL16(&p->buf[0]) != RoQ_MAGIC_NUMBER) ||
65  (AV_RL32(&p->buf[2]) != 0xFFFFFFFF))
66  return 0;
67 
68  return AVPROBE_SCORE_MAX;
69 }
70 
72 {
73  RoqDemuxContext *roq = s->priv_data;
74  AVIOContext *pb = s->pb;
75  unsigned char preamble[RoQ_CHUNK_PREAMBLE_SIZE];
76 
77  /* get the main header */
78  if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) !=
80  return AVERROR(EIO);
81  roq->frame_rate = AV_RL16(&preamble[6]);
82 
83  /* init private context parameters */
84  roq->width = roq->height = roq->audio_channels = roq->video_pts =
85  roq->audio_frame_count = 0;
86  roq->audio_stream_index = -1;
87  roq->video_stream_index = -1;
88 
90 
91  return 0;
92 }
93 
95  AVPacket *pkt)
96 {
97  RoqDemuxContext *roq = s->priv_data;
98  AVIOContext *pb = s->pb;
99  int ret = 0;
100  unsigned int chunk_size;
101  unsigned int chunk_type;
102  unsigned int codebook_size;
103  unsigned char preamble[RoQ_CHUNK_PREAMBLE_SIZE];
104  int packet_read = 0;
105  int64_t codebook_offset;
106 
107  while (!packet_read) {
108 
109  if (url_feof(s->pb))
110  return AVERROR(EIO);
111 
112  /* get the next chunk preamble */
113  if ((ret = avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE)) !=
115  return AVERROR(EIO);
116 
117  chunk_type = AV_RL16(&preamble[0]);
118  chunk_size = AV_RL32(&preamble[2]);
119  if(chunk_size > INT_MAX)
120  return AVERROR_INVALIDDATA;
121 
122  chunk_size = ffio_limit(pb, chunk_size);
123 
124  switch (chunk_type) {
125 
126  case RoQ_INFO:
127  if (roq->video_stream_index == -1) {
128  AVStream *st = avformat_new_stream(s, NULL);
129  if (!st)
130  return AVERROR(ENOMEM);
131  avpriv_set_pts_info(st, 63, 1, roq->frame_rate);
132  roq->video_stream_index = st->index;
135  st->codec->codec_tag = 0; /* no fourcc */
136 
138  return AVERROR(EIO);
139  st->codec->width = roq->width = AV_RL16(preamble);
140  st->codec->height = roq->height = AV_RL16(preamble + 2);
141  break;
142  }
143  /* don't care about this chunk anymore */
145  break;
146 
147  case RoQ_QUAD_CODEBOOK:
148  /* packet needs to contain both this codebook and next VQ chunk */
149  codebook_offset = avio_tell(pb) - RoQ_CHUNK_PREAMBLE_SIZE;
150  codebook_size = chunk_size;
151  avio_skip(pb, codebook_size);
152  if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) !=
154  return AVERROR(EIO);
155  chunk_size = AV_RL32(&preamble[2]) + RoQ_CHUNK_PREAMBLE_SIZE * 2 +
156  codebook_size;
157 
158  /* rewind */
159  avio_seek(pb, codebook_offset, SEEK_SET);
160 
161  /* load up the packet */
162  ret= av_get_packet(pb, pkt, chunk_size);
163  if (ret != chunk_size)
164  return AVERROR(EIO);
165  pkt->stream_index = roq->video_stream_index;
166  pkt->pts = roq->video_pts++;
167 
168  packet_read = 1;
169  break;
170 
171  case RoQ_SOUND_MONO:
172  case RoQ_SOUND_STEREO:
173  if (roq->audio_stream_index == -1) {
174  AVStream *st = avformat_new_stream(s, NULL);
175  if (!st)
176  return AVERROR(ENOMEM);
178  roq->audio_stream_index = st->index;
181  st->codec->codec_tag = 0; /* no tag */
182  if (chunk_type == RoQ_SOUND_STEREO) {
183  st->codec->channels = 2;
185  } else {
186  st->codec->channels = 1;
188  }
189  roq->audio_channels = st->codec->channels;
191  st->codec->bits_per_coded_sample = 16;
192  st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
195  }
196  case RoQ_QUAD_VQ:
197  /* load up the packet */
198  if (av_new_packet(pkt, chunk_size + RoQ_CHUNK_PREAMBLE_SIZE))
199  return AVERROR(EIO);
200  /* copy over preamble */
201  memcpy(pkt->data, preamble, RoQ_CHUNK_PREAMBLE_SIZE);
202 
203  if (chunk_type == RoQ_QUAD_VQ) {
204  pkt->stream_index = roq->video_stream_index;
205  pkt->pts = roq->video_pts++;
206  } else {
207  pkt->stream_index = roq->audio_stream_index;
208  pkt->pts = roq->audio_frame_count;
209  roq->audio_frame_count += (chunk_size / roq->audio_channels);
210  }
211 
212  pkt->pos= avio_tell(pb);
213  ret = avio_read(pb, pkt->data + RoQ_CHUNK_PREAMBLE_SIZE,
214  chunk_size);
215  if (ret != chunk_size)
216  ret = AVERROR(EIO);
217 
218  packet_read = 1;
219  break;
220 
221  default:
222  av_log(s, AV_LOG_ERROR, " unknown RoQ chunk (%04X)\n", chunk_type);
223  return AVERROR_INVALIDDATA;
224  }
225  }
226 
227  return ret;
228 }
229 
231  .name = "roq",
232  .long_name = NULL_IF_CONFIG_SMALL("id RoQ"),
233  .priv_data_size = sizeof(RoqDemuxContext),
237 };