FFmpeg
rka.c
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1 /*
2  * RKA demuxer
3  * Copyright (c) 2023 Paul B Mahol
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 #include "libavutil/dict.h"
23 #include "libavutil/intreadwrite.h"
24 
25 #include "apetag.h"
26 #include "avformat.h"
27 #include "avio_internal.h"
28 #include "demux.h"
29 #include "internal.h"
30 
31 typedef struct RKAContext {
35 } RKAContext;
36 
37 static int rka_probe(const AVProbeData *p)
38 {
39  if (AV_RL32(&p->buf[0]) == MKTAG('R', 'K', 'A', '7') &&
40  AV_RL32(&p->buf[4]) > 0 &&
41  AV_RL32(&p->buf[8]) > 0 &&
42  p->buf[12] > 0 &&
43  p->buf[12] <= 2 &&
44  (p->buf[13] == 8 || p->buf[13] == 16) &&
45  (p->buf[15] & 2) != 0)
46  return AVPROBE_SCORE_EXTENSION + 30;
47  return 0;
48 }
49 
51 {
52  int64_t nb_samples, size_offset;
53  RKAContext *c = s->priv_data;
54  int channels, bps, samplerate;
55  AVCodecParameters *par;
56  int64_t framepos;
57  AVStream *st;
58  int ret;
59 
60  st = avformat_new_stream(s, NULL);
61  if (!st)
62  return AVERROR(ENOMEM);
63 
64  par = st->codecpar;
65  ret = ff_get_extradata(s, par, s->pb, 16);
66  if (ret < 0)
67  return ret;
68 
69  nb_samples = AV_RL32(par->extradata + 4);
70  samplerate = AV_RL32(par->extradata + 8);
71  channels = par->extradata[12];
72  if (channels == 0)
73  return AVERROR_INVALIDDATA;
74  bps = par->extradata[13];
75  if (bps < 8)
76  return AVERROR_INVALIDDATA;
77  size_offset = avio_rl32(s->pb);
78  framepos = avio_tell(s->pb);
79  c->frame_size = 131072;
80 
81  avpriv_set_pts_info(st, 64, 1, samplerate);
82  st->start_time = 0;
83 
84  avio_seek(s->pb, size_offset, SEEK_SET);
85  c->total_frames = (nb_samples + c->frame_size - 1) / c->frame_size;
86  c->last_frame_size = nb_samples % c->frame_size;
87 
88  for (int i = 0; i < c->total_frames; i++) {
89  int r, end = 0;
90  int64_t size;
91 
92  if (avio_feof(s->pb))
93  break;
94 
95  size = avio_rl24(s->pb);
96  if (size == 0) {
97  end = 1;
98  size = size_offset - framepos;
99  if (size <= 0)
100  break;
101  }
102 
103  if ((r = av_add_index_entry(st, framepos, (i * 131072LL) / (channels * (bps >> 3)),
104  size, 0, AVINDEX_KEYFRAME)) < 0)
105  return r;
106  framepos += size;
107 
108  if (end)
109  break;
110  }
111 
113  par->codec_id = AV_CODEC_ID_RKA;
115  par->sample_rate = samplerate;
116  par->bits_per_raw_sample = bps;
117  st->duration = 8LL*nb_samples / (channels * bps);
118 
119  if (s->pb->seekable & AVIO_SEEKABLE_NORMAL)
121 
122  avio_seek(s->pb, 20, SEEK_SET);
123 
124  return 0;
125 }
126 
128 {
129  RKAContext *c = s->priv_data;
130  AVStream *st = s->streams[0];
131  FFStream *const sti = ffstream(st);
132  int size, ret;
133 
134  if (avio_feof(s->pb))
135  return AVERROR_EOF;
136 
137  if (c->currentframe >= sti->nb_index_entries)
138  return AVERROR_EOF;
139 
140  size = sti->index_entries[c->currentframe].size;
141 
142  ret = av_get_packet(s->pb, pkt, size);
143  pkt->dts = sti->index_entries[c->currentframe++].timestamp;
144  pkt->duration = c->currentframe == c->total_frames ? c->last_frame_size :
145  131072;
146  return ret;
147 }
148 
149 static int rka_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
150 {
151  RKAContext *c = s->priv_data;
152  AVStream *st = s->streams[stream_index];
153  int index = av_index_search_timestamp(st, timestamp, flags);
154  if (index < 0)
155  return -1;
156  if (avio_seek(s->pb, ffstream(st)->index_entries[index].pos, SEEK_SET) < 0)
157  return -1;
158 
159  c->currentframe = index;
160 
161  return 0;
162 }
163 
165  .p.name = "rka",
166  .p.long_name = NULL_IF_CONFIG_SMALL("RKA (RK Audio)"),
167  .p.extensions = "rka",
168  .priv_data_size = sizeof(RKAContext),
173 };
rka_read_packet
static int rka_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rka.c:127
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
r
const char * r
Definition: vf_curves.c:127
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
apetag.h
RKAContext::last_frame_size
int last_frame_size
Definition: rka.c:34
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:542
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:313
rka_read_seek
static int rka_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: rka.c:149
ff_ape_parse_tag
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:110
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:610
ff_get_extradata
int ff_get_extradata(void *logctx, AVCodecParameters *par, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: demux_utils.c:335
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:853
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:417
AVCodecParameters::bits_per_raw_sample
int bits_per_raw_sample
This is the number of valid bits in each output sample.
Definition: codec_par.h:123
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
av_add_index_entry
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: seek.c:121
RKAContext::frame_size
int frame_size
Definition: rka.c:33
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
AV_CODEC_ID_RKA
@ AV_CODEC_ID_RKA
Definition: codec_id.h:542
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:802
RKAContext::total_frames
int total_frames
Definition: rka.c:32
pkt
AVPacket * pkt
Definition: movenc.c:60
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
RKAContext
Definition: rka.c:85
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
AVIndexEntry::size
int size
Definition: avformat.h:613
AVIndexEntry::timestamp
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:604
channels
channels
Definition: aptx.h:31
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
NULL
#define NULL
Definition: coverity.c:32
FFStream::nb_index_entries
int nb_index_entries
Definition: internal.h:251
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:180
index
int index
Definition: gxfenc.c:90
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:461
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:730
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:94
FFStream
Definition: internal.h:193
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
bps
unsigned bps
Definition: movenc.c:1852
size
int size
Definition: twinvq_data.h:10344
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
AVPacket::dts
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition: packet.h:523
rka_read_header
static int rka_read_header(AVFormatContext *s)
Definition: rka.c:50
ff_rka_demuxer
const FFInputFormat ff_rka_demuxer
Definition: rka.c:164
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
avio_rl24
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:722
avio_internal.h
demux.h
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:91
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:231
pos
unsigned int pos
Definition: spdifenc.c:414
avformat.h
dict.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
rka_probe
static int rka_probe(const AVProbeData *p)
Definition: rka.c:37
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:41
FFStream::index_entries
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: internal.h:249
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:501
FFInputFormat
Definition: demux.h:37
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:792
RKAContext::currentframe
int currentframe
Definition: rka.c:32
av_index_search_timestamp
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: seek.c:244
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:346