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 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 RoQ_MAGIC_NUMBER 0x1084
36 #define RoQ_CHUNK_PREAMBLE_SIZE 8
37 #define RoQ_AUDIO_SAMPLE_RATE 22050
38 #define RoQ_CHUNKS_TO_SCAN 30
39 
40 #define RoQ_INFO 0x1001
41 #define RoQ_QUAD_CODEBOOK 0x1002
42 #define RoQ_QUAD_VQ 0x1011
43 #define RoQ_SOUND_MONO 0x1020
44 #define RoQ_SOUND_STEREO 0x1021
45 
46 typedef struct RoqDemuxContext {
47 
49  int width;
50  int height;
52 
55 
56  int64_t video_pts;
57  unsigned int audio_frame_count;
58 
60 
61 static int roq_probe(AVProbeData *p)
62 {
63  if ((AV_RL16(&p->buf[0]) != RoQ_MAGIC_NUMBER) ||
64  (AV_RL32(&p->buf[2]) != 0xFFFFFFFF))
65  return 0;
66 
67  return AVPROBE_SCORE_MAX;
68 }
69 
71 {
72  RoqDemuxContext *roq = s->priv_data;
73  AVIOContext *pb = s->pb;
74  unsigned char preamble[RoQ_CHUNK_PREAMBLE_SIZE];
75 
76  /* get the main header */
77  if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) !=
79  return AVERROR(EIO);
80  roq->frame_rate = AV_RL16(&preamble[6]);
81 
82  /* init private context parameters */
83  roq->width = roq->height = roq->audio_channels = roq->video_pts =
84  roq->audio_frame_count = 0;
85  roq->audio_stream_index = -1;
86  roq->video_stream_index = -1;
87 
89 
90  return 0;
91 }
92 
94  AVPacket *pkt)
95 {
96  RoqDemuxContext *roq = s->priv_data;
97  AVIOContext *pb = s->pb;
98  int ret = 0;
99  unsigned int chunk_size;
100  unsigned int chunk_type;
101  unsigned int codebook_size;
102  unsigned char preamble[RoQ_CHUNK_PREAMBLE_SIZE];
103  int packet_read = 0;
104  int64_t codebook_offset;
105 
106  while (!packet_read) {
107 
108  if (s->pb->eof_reached)
109  return AVERROR(EIO);
110 
111  /* get the next chunk preamble */
112  if ((ret = avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE)) !=
114  return AVERROR(EIO);
115 
116  chunk_type = AV_RL16(&preamble[0]);
117  chunk_size = AV_RL32(&preamble[2]);
118  if(chunk_size > INT_MAX)
119  return AVERROR_INVALIDDATA;
120 
121  switch (chunk_type) {
122 
123  case RoQ_INFO:
124  if (roq->video_stream_index == -1) {
126  if (!st)
127  return AVERROR(ENOMEM);
128  avpriv_set_pts_info(st, 63, 1, roq->frame_rate);
129  roq->video_stream_index = st->index;
132  st->codec->codec_tag = 0; /* no fourcc */
133 
135  return AVERROR(EIO);
136  st->codec->width = roq->width = AV_RL16(preamble);
137  st->codec->height = roq->height = AV_RL16(preamble + 2);
138  break;
139  }
140  /* don't care about this chunk anymore */
142  break;
143 
144  case RoQ_QUAD_CODEBOOK:
145  if (roq->video_stream_index < 0)
146  return AVERROR_INVALIDDATA;
147  /* packet needs to contain both this codebook and next VQ chunk */
148  codebook_offset = avio_tell(pb) - RoQ_CHUNK_PREAMBLE_SIZE;
149  codebook_size = chunk_size;
150  avio_skip(pb, codebook_size);
151  if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) !=
153  return AVERROR(EIO);
154  chunk_size = AV_RL32(&preamble[2]) + RoQ_CHUNK_PREAMBLE_SIZE * 2 +
155  codebook_size;
156 
157  /* rewind */
158  avio_seek(pb, codebook_offset, SEEK_SET);
159 
160  /* load up the packet */
161  ret= av_get_packet(pb, pkt, chunk_size);
162  if (ret != chunk_size)
163  return AVERROR(EIO);
164  pkt->stream_index = roq->video_stream_index;
165  pkt->pts = roq->video_pts++;
166 
167  packet_read = 1;
168  break;
169 
170  case RoQ_SOUND_MONO:
171  case RoQ_SOUND_STEREO:
172  if (roq->audio_stream_index == -1) {
174  if (!st)
175  return AVERROR(ENOMEM);
177  roq->audio_stream_index = st->index;
180  st->codec->codec_tag = 0; /* no tag */
181  if (chunk_type == RoQ_SOUND_STEREO) {
182  st->codec->channels = 2;
184  } else {
185  st->codec->channels = 1;
187  }
188  roq->audio_channels = st->codec->channels;
190  st->codec->bits_per_coded_sample = 16;
191  st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
194  }
195  case RoQ_QUAD_VQ:
196  if (chunk_type == RoQ_QUAD_VQ) {
197  if (roq->video_stream_index < 0)
198  return AVERROR_INVALIDDATA;
199  }
200 
201  /* load up the packet */
202  if (av_new_packet(pkt, chunk_size + RoQ_CHUNK_PREAMBLE_SIZE))
203  return AVERROR(EIO);
204  /* copy over preamble */
205  memcpy(pkt->data, preamble, RoQ_CHUNK_PREAMBLE_SIZE);
206 
207  if (chunk_type == RoQ_QUAD_VQ) {
208  pkt->stream_index = roq->video_stream_index;
209  pkt->pts = roq->video_pts++;
210  } else {
211  pkt->stream_index = roq->audio_stream_index;
212  pkt->pts = roq->audio_frame_count;
213  roq->audio_frame_count += (chunk_size / roq->audio_channels);
214  }
215 
216  pkt->pos= avio_tell(pb);
217  ret = avio_read(pb, pkt->data + RoQ_CHUNK_PREAMBLE_SIZE,
218  chunk_size);
219  if (ret != chunk_size)
220  ret = AVERROR(EIO);
221 
222  packet_read = 1;
223  break;
224 
225  default:
226  av_log(s, AV_LOG_ERROR, " unknown RoQ chunk (%04X)\n", chunk_type);
227  return AVERROR_INVALIDDATA;
228  }
229  }
230 
231  return ret;
232 }
233 
235  .name = "roq",
236  .long_name = NULL_IF_CONFIG_SMALL("id RoQ"),
237  .priv_data_size = sizeof(RoqDemuxContext),
241 };