rsodec.c
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1 /*
2  * RSO demuxer
3  * Copyright (c) 2001 Fabrice Bellard (original AU code)
4  * Copyright (c) 2010 Rafael Carre
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
24 #include "libavutil/intreadwrite.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "pcm.h"
28 #include "rso.h"
29 
31 {
32  AVIOContext *pb = s->pb;
33  int id, rate, bps;
34  unsigned int size;
35  enum AVCodecID codec;
36  AVStream *st;
37 
38  id = avio_rb16(pb);
39  size = avio_rb16(pb);
40  rate = avio_rb16(pb);
41  avio_rb16(pb); /* play mode ? (0x0000 = don't loop) */
42 
44 
45  if (codec == AV_CODEC_ID_ADPCM_IMA_WAV) {
46  av_log(s, AV_LOG_ERROR, "ADPCM in RSO not implemented\n");
47  return AVERROR_PATCHWELCOME;
48  }
49 
50  bps = av_get_bits_per_sample(codec);
51  if (!bps) {
52  av_log_ask_for_sample(s, "could not determine bits per sample\n");
53  return AVERROR_PATCHWELCOME;
54  }
55 
56  /* now we are ready: build format streams */
57  st = avformat_new_stream(s, NULL);
58  if (!st)
59  return AVERROR(ENOMEM);
60 
61  st->duration = (size * 8) / bps;
63  st->codec->codec_tag = id;
64  st->codec->codec_id = codec;
65  st->codec->channels = 1;
67  st->codec->sample_rate = rate;
68 
69  avpriv_set_pts_info(st, 64, 1, rate);
70 
71  return 0;
72 }
73 
74 #define BLOCK_SIZE 1024 /* in samples */
75 
77 {
79  int ret = av_get_packet(s->pb, pkt, BLOCK_SIZE * bps >> 3);
80 
81  if (ret < 0)
82  return ret;
83 
84  pkt->stream_index = 0;
85 
86  /* note: we need to modify the packet size here to handle the last packet */
87  pkt->size = ret;
88 
89  return 0;
90 }
91 
93  .name = "rso",
94  .long_name = NULL_IF_CONFIG_SMALL("Lego Mindstorms RSO"),
95  .extensions = "rso",
96  .read_header = rso_read_header,
97  .read_packet = rso_read_packet,
98  .read_seek = ff_pcm_read_seek,
99  .codec_tag = (const AVCodecTag* const []){ff_codec_rso_tags, 0},
100 };
Bytestream IO Context.
Definition: avio.h:68
int size
enum AVCodecID id
Definition: mxfenc.c:85
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:2126
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:3283
static int rso_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rsodec.c:76
int size
Definition: avcodec.h:916
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:562
AVInputFormat ff_rso_demuxer
Definition: rsodec.c:92
Format I/O context.
Definition: avformat.h:828
AVStream ** streams
Definition: avformat.h:876
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:218
static int rso_read_header(AVFormatContext *s)
Definition: rsodec.c:30
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:95
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:1811
void av_log_ask_for_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message asking for a sample.
#define BLOCK_SIZE
Definition: rsodec.c:74
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:88
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:146
AVStream * avformat_new_stream(AVFormatContext *s, AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2736
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2165
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:641
audio channel layout utility functions
int ff_pcm_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: pcm.c:26
const AVCodecTag ff_codec_rso_tags[]
Definition: rso.c:26
Stream structure.
Definition: avformat.h:622
NULL
Definition: eval.c:52
enum AVMediaType codec_type
Definition: avcodec.h:1347
enum AVCodecID codec_id
Definition: avcodec.h:1350
int sample_rate
samples per second
Definition: avcodec.h:2104
AVIOContext * pb
I/O context.
Definition: avformat.h:861
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1365
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:684
Main libavformat public API header.
unsigned bps
Definition: movenc.c:803
int channels
number of audio channels
Definition: avcodec.h:2105
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:455
int stream_index
Definition: avcodec.h:917
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:898