FFmpeg  2.1.1
adxdec.c
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1 /*
2  * Copyright (c) 2011 Justin Ruggles
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * CRI ADX demuxer
24  */
25 
26 #include "libavutil/intreadwrite.h"
27 #include "libavcodec/adx.h"
28 #include "avformat.h"
29 #include "internal.h"
30 
31 #define BLOCK_SIZE 18
32 #define BLOCK_SAMPLES 32
33 
34 typedef struct ADXDemuxerContext {
37 
39 {
41  AVCodecContext *avctx = s->streams[0]->codec;
42  int ret, size;
43 
44  size = BLOCK_SIZE * avctx->channels;
45 
46  pkt->pos = avio_tell(s->pb);
47  pkt->stream_index = 0;
48 
49  ret = av_get_packet(s->pb, pkt, size);
50  if (ret != size) {
51  av_free_packet(pkt);
52  return ret < 0 ? ret : AVERROR(EIO);
53  }
54  if (AV_RB16(pkt->data) & 0x8000) {
55  av_free_packet(pkt);
56  return AVERROR_EOF;
57  }
58  pkt->size = size;
59  pkt->duration = 1;
60  pkt->pts = (pkt->pos - c->header_size) / size;
61 
62  return 0;
63 }
64 
66 {
68  AVCodecContext *avctx;
69  int ret;
70 
71  AVStream *st = avformat_new_stream(s, NULL);
72  if (!st)
73  return AVERROR(ENOMEM);
74  avctx = s->streams[0]->codec;
75 
76  if (avio_rb16(s->pb) != 0x8000)
77  return AVERROR_INVALIDDATA;
78  c->header_size = avio_rb16(s->pb) + 4;
79  avio_seek(s->pb, -4, SEEK_CUR);
80 
81  if (ff_alloc_extradata(avctx, c->header_size))
82  return AVERROR(ENOMEM);
83  if (avio_read(s->pb, avctx->extradata, c->header_size) < c->header_size) {
84  av_freep(&avctx->extradata);
85  return AVERROR(EIO);
86  }
87  avctx->extradata_size = c->header_size;
88 
89  ret = avpriv_adx_decode_header(avctx, avctx->extradata,
90  avctx->extradata_size, &c->header_size,
91  NULL);
92  if (ret)
93  return ret;
94 
97 
99 
100  return 0;
101 }
102 
104  .name = "adx",
105  .long_name = NULL_IF_CONFIG_SMALL("CRI ADX"),
106  .priv_data_size = sizeof(ADXDemuxerContext),
109  .extensions = "adx",
110  .raw_codec_id = AV_CODEC_ID_ADPCM_ADX,
112 };
const char * s
Definition: avisynth_c.h:668
int size
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:279
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:478
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1092
static int adx_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: adxdec.c:38
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:3922
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:686
int size
Definition: avcodec.h:1064
#define BLOCK_SAMPLES
Definition: adxdec.c:32
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1254
void av_freep(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:234
Format I/O context.
Definition: avformat.h:968
#define AV_RB16(x)
Definition: intreadwrite.h:232
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:248
static int adx_read_header(AVFormatContext *s)
Definition: adxdec.c:65
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3348
int duration
Duration of this packet in AVStream-&gt;time_base units, 0 if unknown.
Definition: avcodec.h:1085
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:200
#define BLOCK_SIZE
Definition: adxdec.c:31
void * priv_data
Format private data.
Definition: avformat.h:988
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
struct AVInputFormat * iformat
Can only be iformat or oformat, not both at the same time.
Definition: avformat.h:981
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:355
ret
Definition: avfilter.c:961
AVStream ** streams
Definition: avformat.h:1016
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:199
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:592
Stream structure.
Definition: avformat.h:667
enum AVMediaType codec_type
Definition: avcodec.h:1154
enum AVCodecID codec_id
Definition: avcodec.h:1157
int sample_rate
samples per second
Definition: avcodec.h:1873
main external API structure.
Definition: avcodec.h:1146
int ff_alloc_extradata(AVCodecContext *avctx, int size)
Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:2690
AVIOContext * pb
I/O context.
Definition: avformat.h:1001
int extradata_size
Definition: avcodec.h:1255
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
uint8_t * data
Definition: avcodec.h:1063
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:517
static int flags
Definition: cpu.c:45
#define AVERROR_EOF
int avpriv_adx_decode_header(AVCodecContext *avctx, const uint8_t *buf, int bufsize, int *header_size, int *coeff)
Decode ADX stream header.
Definition: adx.c:38
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:480
static double c[64]
Main libavformat public API header.
#define AVERROR_INVALIDDATA
int channels
number of audio channels
Definition: avcodec.h:1874
#define AVERROR(e)
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:609
static AVPacket pkt
Definition: demuxing.c:52
int stream_index
Definition: avcodec.h:1065
SEGA CRI adx codecs.
AVInputFormat ff_adx_demuxer
Definition: adxdec.c:103
This structure stores compressed data.
Definition: avcodec.h:1040
int64_t pts
Presentation timestamp in AVStream-&gt;time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1056