FFmpeg  2.1.1
eacdata.c
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1 /*
2  * Electronic Arts .cdata file Demuxer
3  * Copyright (c) 2007 Peter Ross
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  * Electronic Arts cdata Format Demuxer
25  * by Peter Ross (pross@xvid.org)
26  *
27  * Technical details here:
28  * http://wiki.multimedia.cx/index.php?title=EA_Command_And_Conquer_3_Audio_Codec
29  */
30 
31 #include "avformat.h"
32 #include "internal.h"
33 
34 typedef struct {
35  unsigned int channels;
36  unsigned int audio_pts;
38 
39 static int cdata_probe(AVProbeData *p)
40 {
41  const uint8_t *b = p->buf;
42 
43  if (b[0] == 0x04 && (b[1] == 0x00 || b[1] == 0x04 || b[1] == 0x0C || b[1] == 0x14))
44  return AVPROBE_SCORE_MAX/8;
45  return 0;
46 }
47 
49 {
50  CdataDemuxContext *cdata = s->priv_data;
51  AVIOContext *pb = s->pb;
52  unsigned int sample_rate, header;
53  AVStream *st;
54  int64_t channel_layout = 0;
55 
56  header = avio_rb16(pb);
57  switch (header) {
58  case 0x0400: cdata->channels = 1; break;
59  case 0x0404: cdata->channels = 2; break;
60  case 0x040C: cdata->channels = 4; channel_layout = AV_CH_LAYOUT_QUAD; break;
61  case 0x0414: cdata->channels = 6; channel_layout = AV_CH_LAYOUT_5POINT1_BACK; break;
62  default:
63  av_log(s, AV_LOG_INFO, "unknown header 0x%04x\n", header);
64  return -1;
65  };
66 
67  sample_rate = avio_rb16(pb);
68  avio_skip(pb, (avio_r8(pb) & 0x20) ? 15 : 11);
69 
70  st = avformat_new_stream(s, NULL);
71  if (!st)
72  return AVERROR(ENOMEM);
74  st->codec->codec_tag = 0; /* no fourcc */
76  st->codec->channels = cdata->channels;
77  st->codec->channel_layout = channel_layout;
79  avpriv_set_pts_info(st, 64, 1, sample_rate);
80 
81  cdata->audio_pts = 0;
82  return 0;
83 }
84 
86 {
87  CdataDemuxContext *cdata = s->priv_data;
88  int packet_size = 76*cdata->channels;
89 
90  int ret = av_get_packet(s->pb, pkt, packet_size);
91  if (ret < 0)
92  return ret;
93  pkt->pts = cdata->audio_pts++;
94  return 0;
95 }
96 
98  .name = "ea_cdata",
99  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts cdata"),
100  .priv_data_size = sizeof(CdataDemuxContext),
104  .extensions = "cdata",
105 };
const char * s
Definition: avisynth_c.h:668
Bytestream IO Context.
Definition: avio.h:68
static int cdata_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: eacdata.c:85
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:478
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
const char * b
Definition: vf_curves.c:105
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:471
Format I/O context.
Definition: avformat.h:968
uint8_t
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:336
unsigned int audio_pts
Definition: eacdata.c:36
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3348
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
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
#define AV_CH_LAYOUT_QUAD
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1934
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:54
ret
Definition: avfilter.c:961
AVInputFormat ff_ea_cdata_demuxer
Definition: eacdata.c:97
#define AV_CH_LAYOUT_5POINT1_BACK
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:592
Stream structure.
Definition: avformat.h:667
sample_rate
#define AV_LOG_INFO
Standard information.
Definition: avcodec.h:4158
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
unsigned int codec_tag
fourcc (LSB first, so &quot;ABCD&quot; -&gt; (&#39;D&#39;&lt;&lt;24) + (&#39;C&#39;&lt;&lt;16) + (&#39;B&#39;&lt;&lt;8) + &#39;A&#39;).
Definition: avcodec.h:1172
AVIOContext * pb
I/O context.
Definition: avformat.h:1001
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
This structure contains the data a format has to probe a file.
Definition: avformat.h:334
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:256
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:342
Main libavformat public API header.
int channels
number of audio channels
Definition: avcodec.h:1874
unsigned int channels
Definition: eacdata.c:35
#define AVERROR(e)
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:609
static AVPacket pkt
Definition: demuxing.c:52
static int cdata_probe(AVProbeData *p)
Definition: eacdata.c:39
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
static int cdata_read_header(AVFormatContext *s)
Definition: eacdata.c:48