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) {
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) {
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 };
int audio_channels
Definition: idroqdec.c:52
const char * s
Definition: avisynth_c.h:668
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
unsigned int audio_frame_count
Definition: idroqdec.c:58
int64_t pos
byte position in stream, -1 if unknown
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
int index
Definition: avformat.h:644
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
Definition: aviobuf.c:199
static int roq_probe(AVProbeData *p)
Definition: idroqdec.c:62
int64_t video_pts
Definition: idroqdec.c:57
#define AV_RL16
int64_t avio_skip(AVIOContext *s, int64_t offset)
Definition: aviobuf.c:256
#define AV_CH_LAYOUT_STEREO
#define RoQ_SOUND_STEREO
Definition: idroqdec.c:45
#define RoQ_MAGIC_NUMBER
Definition: idroqdec.c:36
int ffio_limit(AVIOContext *s, int size)
#define AVFMTCTX_NOHEADER
Definition: avformat.h:914
static AVPacket pkt
Definition: demuxing.c:56
static int roq_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: idroqdec.c:94
#define RoQ_INFO
Definition: idroqdec.c:41
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
uint8_t * data
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
static av_always_inline int64_t avio_tell(AVIOContext *s)
Definition: avio.h:248
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Definition: aviobuf.c:478
int av_new_packet(AVPacket *pkt, int size)
Definition: avpacket.c:73
int audio_stream_index
Definition: idroqdec.c:55
#define NULL_IF_CONFIG_SMALL(x)
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:246
#define RoQ_SOUND_MONO
Definition: idroqdec.c:44
AVCodecContext * codec
Definition: avformat.h:662
unsigned char * buf
Definition: avformat.h:336
static int read_probe(AVProbeData *pd)
ret
Definition: avfilter.c:821
#define AV_RL32
int url_feof(AVIOContext *s)
Definition: aviobuf.c:280
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:517
NULL
Definition: eval.c:55
enum AVMediaType codec_type
enum AVCodecID codec_id
int sample_rate
samples per second
AVIOContext * pb
Definition: avformat.h:977
#define AV_LOG_ERROR
Definition: log.h:148
unsigned int codec_tag
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
struct RoqDemuxContext RoqDemuxContext
#define RoQ_CHUNK_PREAMBLE_SIZE
Definition: idroqdec.c:37
#define RoQ_AUDIO_SAMPLE_RATE
Definition: idroqdec.c:38
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFilterBuffer structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Buffer references ownership and permissions
#define AVPROBE_SCORE_MAX
maximum score, half of that is used for file-extension-based detection
Definition: avformat.h:340
int channels
number of audio channels
int video_stream_index
Definition: idroqdec.c:54
void * priv_data
Definition: avformat.h:964
const char * name
Definition: avformat.h:461
#define RoQ_QUAD_CODEBOOK
Definition: idroqdec.c:42
#define AV_CH_LAYOUT_MONO
AVInputFormat ff_roq_demuxer
Definition: idroqdec.c:230
static int roq_read_header(AVFormatContext *s)
Definition: idroqdec.c:71
#define RoQ_QUAD_VQ
Definition: idroqdec.c:43