FFmpeg
binka.c
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1 /*
2  * Copyright (c) 2021 Paul B Mahol
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 #include "libavutil/intreadwrite.h"
22 #include "avformat.h"
23 #include "internal.h"
24 
25 static int binka_probe(const AVProbeData *p)
26 {
27  if (AV_RB32(p->buf) == MKBETAG('1', 'F', 'C', 'B') &&
28  (p->buf[4] == 1 || p->buf[4] == 2))
29  return AVPROBE_SCORE_MAX;
30  return 0;
31 }
32 
34 {
35  AVIOContext *pb = s->pb;
36  AVStream *st;
37  int entries, offset;
38 
39  st = avformat_new_stream(s, NULL);
40  if (!st)
41  return AVERROR(ENOMEM);
42 
43  avio_skip(pb, 5);
44 
48  st->codecpar->sample_rate = avio_rl16(pb);
49  st->duration = avio_rl32(pb);
50 
51  avio_skip(pb, 8);
52  entries = avio_rl16(pb);
53 
54  offset = entries * 2 + 2;
55  avio_skip(pb, offset);
56 
57  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
58 
59  return 0;
60 }
61 
63 {
64  AVIOContext *pb = s->pb;
65  AVStream *st = s->streams[0];
66  int64_t pos;
67  int pkt_size;
68  int ret;
69 
70  if (avio_feof(pb))
71  return AVERROR_EOF;
72 
73  pos = avio_tell(pb);
74  avio_skip(pb, 2);
75  pkt_size = avio_rl16(pb) + 4;
76  if (pkt_size <= 4)
77  return AVERROR(EIO);
78  ret = av_new_packet(pkt, pkt_size);
79  if (ret < 0)
80  return ret;
81 
82  avio_read(pb, pkt->data + 4, pkt_size - 4);
83  AV_WL32(pkt->data, pkt_size);
84 
85  pkt->pos = pos;
86  pkt->stream_index = 0;
88 
89  return 0;
90 }
91 
93  .name = "binka",
94  .long_name = NULL_IF_CONFIG_SMALL("Bink Audio"),
95  .read_probe = binka_probe,
96  .read_header = binka_read_header,
97  .read_packet = binka_read_packet,
98  .flags = AVFMT_GENERIC_INDEX,
99  .extensions = "binka",
100 };
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:243
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
AV_WL32
#define AV_WL32(p, v)
Definition: intreadwrite.h:426
binka_read_packet
static int binka_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: binka.c:62
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:392
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
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:771
ff_binka_demuxer
const AVInputFormat ff_binka_demuxer
Definition: binka.c:92
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:500
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:897
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:735
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:546
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:551
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_CODEC_ID_BINKAUDIO_DCT
@ AV_CODEC_ID_BINKAUDIO_DCT
Definition: codec_id.h:486
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:861
NULL
#define NULL
Definition: coverity.c:32
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:751
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
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:115
MKBETAG
#define MKBETAG(a, b, c, d)
Definition: macros.h:56
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
av_get_audio_frame_duration2
int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes)
This function is the same as av_get_audio_frame_duration(), except it works with AVCodecParameters in...
Definition: utils.c:837
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:838
binka_probe
static int binka_probe(const AVProbeData *p)
Definition: binka.c:25
pos
unsigned int pos
Definition: spdifenc.c:413
avformat.h
binka_read_header
static int binka_read_header(AVFormatContext *s)
Definition: binka.c:33
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
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:339
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:367