FFmpeg: libavformat/idroqdec.c Source File

FFmpeg
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 
30 #include "libavutil/channel_layout.h"
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 
49   int frame_rate;
50   int width;
51   int height;
52   int audio_channels;
53 
54   int video_stream_index;
55   int audio_stream_index;
56 
57   int64_t video_pts;
58   unsigned int audio_frame_count;
59 
60 } RoqDemuxContext;
61 
62  static int roq_probe(const 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 
71  static int roq_read_header(AVFormatContext *s)
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) !=
79  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 
89  s->ctx_flags |= AVFMTCTX_NOHEADER;
90 
91  return 0;
92 }
93 
94  static int roq_read_packet(AVFormatContext *s,
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 (avio_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)) !=
114  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;
133  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
134  st->codecpar->codec_id = AV_CODEC_ID_ROQ;
135  st->codecpar->codec_tag = 0; /* no fourcc */
136 
137  if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) != RoQ_CHUNK_PREAMBLE_SIZE)
138  return AVERROR(EIO);
139  st->codecpar->width = roq->width = AV_RL16(preamble);
140  st->codecpar->height = roq->height = AV_RL16(preamble + 2);
141  break;
142  }
143  /* don't care about this chunk anymore */
144  avio_skip(pb, RoQ_CHUNK_PREAMBLE_SIZE);
145  break;
146 
147  case RoQ_QUAD_CODEBOOK:
148  if (roq->video_stream_index < 0)
149  return AVERROR_INVALIDDATA;
150  /* packet needs to contain both this codebook and next VQ chunk */
151  codebook_offset = avio_tell(pb) - RoQ_CHUNK_PREAMBLE_SIZE;
152  codebook_size = chunk_size;
153  avio_skip(pb, codebook_size);
154  if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) !=
155  RoQ_CHUNK_PREAMBLE_SIZE)
156  return AVERROR(EIO);
157  chunk_size = AV_RL32(&preamble[2]) + RoQ_CHUNK_PREAMBLE_SIZE * 2 +
158  codebook_size;
159 
160  if (chunk_size > INT_MAX)
161  return AVERROR_INVALIDDATA;
162 
163  /* rewind */
164  avio_seek(pb, codebook_offset, SEEK_SET);
165 
166  /* load up the packet */
167  ret= av_get_packet(pb, pkt, chunk_size);
168  if (ret != chunk_size)
169  return AVERROR(EIO);
170  pkt->stream_index = roq->video_stream_index;
171  pkt->pts = roq->video_pts++;
172 
173  packet_read = 1;
174  break;
175 
176  case RoQ_SOUND_MONO:
177  case RoQ_SOUND_STEREO:
178  if (roq->audio_stream_index == -1) {
179  AVStream *st = avformat_new_stream(s, NULL);
180  if (!st)
181  return AVERROR(ENOMEM);
182  avpriv_set_pts_info(st, 32, 1, RoQ_AUDIO_SAMPLE_RATE);
183  roq->audio_stream_index = st->index;
184  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
185  st->codecpar->codec_id = AV_CODEC_ID_ROQ_DPCM;
186  st->codecpar->codec_tag = 0; /* no tag */
187  if (chunk_type == RoQ_SOUND_STEREO) {
188  st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_STEREO;
189  } else {
190  st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
191  }
192  roq->audio_channels = st->codecpar->ch_layout.nb_channels;
193  st->codecpar->sample_rate = RoQ_AUDIO_SAMPLE_RATE;
194  st->codecpar->bits_per_coded_sample = 16;
195  st->codecpar->bit_rate = roq->audio_channels * st->codecpar->sample_rate *
196  st->codecpar->bits_per_coded_sample;
197  st->codecpar->block_align = roq->audio_channels * st->codecpar->bits_per_coded_sample;
198  }
199  case RoQ_QUAD_VQ:
200  if (chunk_type == RoQ_QUAD_VQ) {
201  if (roq->video_stream_index < 0)
202  return AVERROR_INVALIDDATA;
203  }
204 
205  /* load up the packet */
206  ret = av_new_packet(pkt, chunk_size + RoQ_CHUNK_PREAMBLE_SIZE);
207  if (ret < 0)
208  return ret;
209  /* copy over preamble */
210  memcpy(pkt->data, preamble, RoQ_CHUNK_PREAMBLE_SIZE);
211 
212  if (chunk_type == RoQ_QUAD_VQ) {
213  pkt->stream_index = roq->video_stream_index;
214  pkt->pts = roq->video_pts++;
215  } else {
216  pkt->stream_index = roq->audio_stream_index;
217  pkt->pts = roq->audio_frame_count;
218  roq->audio_frame_count += (chunk_size / roq->audio_channels);
219  }
220 
221  pkt->pos= avio_tell(pb);
222  ret = avio_read(pb, pkt->data + RoQ_CHUNK_PREAMBLE_SIZE,
223  chunk_size);
224  if (ret != chunk_size) {
225  return AVERROR(EIO);
226  }
227 
228  packet_read = 1;
229  break;
230 
231  default:
232  av_log(s, AV_LOG_ERROR, " unknown RoQ chunk (%04X)\n", chunk_type);
233  return AVERROR_INVALIDDATA;
234  }
235  }
236 
237  return ret;
238 }
239 
240  const AVInputFormat ff_roq_demuxer = {
241  .name = "roq",
242  .long_name = NULL_IF_CONFIG_SMALL("id RoQ"),
243  .priv_data_size = sizeof(RoqDemuxContext),
244  .read_probe = roq_probe,
245  .read_header = roq_read_header,
246  .read_packet = roq_read_packet,
247 };
RoqDemuxContext::audio_channels
int audio_channels
Definition: idroqdec.c:52
AVERROR
Filter the word "frame" indicates either a video frame or a group of audio as stored in an AVFrame 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. Frame references ownership and permissions
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
RoqDemuxContext::width
int width
Definition: idroqdec.c:50
AVPacket::data
uint8_t * data
Definition: packet.h:374
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:353
AV_CHANNEL_LAYOUT_STEREO
#define AV_CHANNEL_LAYOUT_STEREO
Definition: channel_layout.h:354
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:65
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:300
RoqDemuxContext
Definition: idroqdec.c:47
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:697
RoQ_MAGIC_NUMBER
#define RoQ_MAGIC_NUMBER
Definition: idroqdec.c:36
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:505
RoqDemuxContext::audio_stream_index
int audio_stream_index
Definition: idroqdec.c:55
RoQ_INFO
#define RoQ_INFO
Definition: idroqdec.c:41
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:656
roq_read_packet
static int roq_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: idroqdec.c:94
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:127
RoqDemuxContext::height
int height
Definition: idroqdec.c:51
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
AVFormatContext
Format I/O context.
Definition: avformat.h:1213
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:532
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVFMTCTX_NOHEADER
#define AVFMTCTX_NOHEADER
signal that no header is present (streams are added dynamically)
Definition: avformat.h:1164
RoqDemuxContext::video_pts
int64_t video_pts
Definition: idroqdec.c:57
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
AV_CODEC_ID_ROQ_DPCM
@ AV_CODEC_ID_ROQ_DPCM
Definition: codec_id.h:418
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
RoQ_QUAD_CODEBOOK
#define RoQ_QUAD_CODEBOOK
Definition: idroqdec.c:42
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
AV_CODEC_ID_ROQ
@ AV_CODEC_ID_ROQ
Definition: codec_id.h:88
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:290
ffio_limit
int ffio_limit(AVIOContext *s, int size)
Definition: aviobuf.c:1093
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:367
avio_internal.h
AVCodecParameters::height
int height
Definition: codec_par.h:128
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:184
roq_read_header
static int roq_read_header(AVFormatContext *s)
Definition: idroqdec.c:71
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:102
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:948
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
avformat.h
roq_probe
static int roq_probe(const AVProbeData *p)
Definition: idroqdec.c:62
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:956
channel_layout.h
RoqDemuxContext::frame_rate
int frame_rate
Definition: idroqdec.c:49
RoQ_CHUNK_PREAMBLE_SIZE
#define RoQ_CHUNK_PREAMBLE_SIZE
Definition: idroqdec.c:37
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:641
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
RoQ_QUAD_VQ
#define RoQ_QUAD_VQ
Definition: idroqdec.c:43
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:103
RoQ_SOUND_STEREO
#define RoQ_SOUND_STEREO
Definition: idroqdec.c:45
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
RoqDemuxContext::video_stream_index
int video_stream_index
Definition: idroqdec.c:54
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
RoQ_SOUND_MONO
#define RoQ_SOUND_MONO
Definition: idroqdec.c:44
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:90
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ff_roq_demuxer
const AVInputFormat ff_roq_demuxer
Definition: idroqdec.c:240
RoQ_AUDIO_SAMPLE_RATE
#define RoQ_AUDIO_SAMPLE_RATE
Definition: idroqdec.c:38
RoqDemuxContext::audio_frame_count
unsigned int audio_frame_count
Definition: idroqdec.c:58
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:375
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