FFmpeg
hca.c
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1 /*
2  * HCA demuxer
3  * Copyright (c) 2020 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/intreadwrite.h"
23 #include "libavcodec/bytestream.h"
24 
25 #include "avformat.h"
26 #include "internal.h"
27 
28 static int hca_probe(const AVProbeData *p)
29 {
30  if (AV_RL32(p->buf) != MKTAG('H', 'C', 'A', 0))
31  return 0;
32 
33  if (AV_RL32(p->buf + 8) != MKTAG('f', 'm', 't', 0))
34  return 0;
35 
36  return AVPROBE_SCORE_MAX / 3;
37 }
38 
40 {
41  AVCodecParameters *par;
42  GetByteContext gb;
43  AVIOContext *pb = s->pb;
44  AVStream *st;
45  uint32_t chunk;
46  uint16_t version;
47  uint32_t block_count;
48  uint16_t block_size;
49  int ret;
50 
51  avio_skip(pb, 4);
52  version = avio_rb16(pb);
53 
54  s->internal->data_offset = avio_rb16(pb);
55  if (s->internal->data_offset <= 8)
56  return AVERROR_INVALIDDATA;
57 
58  st = avformat_new_stream(s, NULL);
59  if (!st)
60  return AVERROR(ENOMEM);
61 
62  par = st->codecpar;
63  ret = ff_alloc_extradata(par, s->internal->data_offset);
64  if (ret < 0)
65  return ret;
66 
67  ret = avio_read(pb, par->extradata + 8, par->extradata_size - 8);
68  if (ret < par->extradata_size - 8)
69  return AVERROR(EIO);
70  AV_WL32(par->extradata, MKTAG('H', 'C', 'A', 0));
71  AV_WB16(par->extradata + 4, version);
72  AV_WB16(par->extradata + 6, s->internal->data_offset);
73 
74  bytestream2_init(&gb, par->extradata + 8, par->extradata_size - 8);
75 
76  if (bytestream2_get_le32(&gb) != MKTAG('f', 'm', 't', 0))
77  return AVERROR_INVALIDDATA;
78 
81  par->codec_tag = 0;
82  par->channels = bytestream2_get_byte(&gb);
83  par->sample_rate = bytestream2_get_be24(&gb);
84  block_count = bytestream2_get_be32(&gb);
85  bytestream2_skip(&gb, 4);
86  chunk = bytestream2_get_le32(&gb);
87  if (chunk == MKTAG('c', 'o', 'm', 'p')) {
88  block_size = bytestream2_get_be16(&gb);
89  } else if (chunk == MKTAG('d', 'e', 'c', 0)) {
90  block_size = bytestream2_get_be16(&gb);
91  } else {
92  return AVERROR_INVALIDDATA;
93  }
94 
95  if (block_size < 8)
96  return AVERROR_INVALIDDATA;
97  par->block_align = block_size;
98  st->duration = 1024 * block_count;
99 
100  avio_seek(pb, s->internal->data_offset, SEEK_SET);
101  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
102 
103  return 0;
104 }
105 
107 {
108  AVCodecParameters *par = s->streams[0]->codecpar;
109  int ret;
110 
111  ret = av_get_packet(s->pb, pkt, par->block_align);
112  pkt->duration = 1024;
113  return ret;
114 }
115 
117  .name = "hca",
118  .long_name = NULL_IF_CONFIG_SMALL("CRI HCA"),
119  .read_probe = hca_probe,
120  .read_header = hca_read_header,
121  .read_packet = hca_read_packet,
122  .extensions = "hca",
123  .flags = AVFMT_GENERIC_INDEX,
124 };
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
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: utils.c:4347
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AV_WL32
#define AV_WL32(p, v)
Definition: intreadwrite.h:426
GetByteContext
Definition: bytestream.h:33
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:391
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:890
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:626
hca_read_packet
static int hca_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: hca.c:106
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:631
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
NULL
#define NULL
Definition: coverity.c:32
AV_WB16
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
ff_hca_demuxer
const AVInputFormat ff_hca_demuxer
Definition: hca.c:116
hca_read_header
static int hca_read_header(AVFormatContext *s)
Definition: hca.c:39
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
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:117
avpriv_set_pts_info
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:4771
version
version
Definition: libkvazaar.c:307
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
hca_probe
static int hca_probe(const AVProbeData *p)
Definition: hca.c:28
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:257
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:847
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:758
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:625
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:333
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
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
AV_CODEC_ID_HCA
@ AV_CODEC_ID_HCA
Definition: codec_id.h:515
ff_alloc_extradata
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0.
Definition: utils.c:3243