FFmpeg  4.4.6
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 };
Main libavformat public API header.
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
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:310
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:766
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
#define AV_RL32
Definition: intreadwrite.h:146
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
#define s(width, name)
Definition: cbs_vp9.c:257
#define MKTAG(a, b, c, d)
Definition: common.h:478
#define NULL
Definition: coverity.c:32
@ AV_CODEC_ID_HCA
Definition: codec_id.h:518
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
static int hca_probe(const AVProbeData *p)
Definition: hca.c:28
AVInputFormat ff_hca_demuxer
Definition: hca.c:116
static int hca_read_header(AVFormatContext *s)
Definition: hca.c:39
static int hca_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: hca.c:106
#define AV_WL32(p, v)
Definition: intreadwrite.h:426
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
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:4945
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:3314
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
version
Definition: libkvazaar.c:326
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
int channels
Audio only.
Definition: codec_par.h:166
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int block_align
Audio only.
Definition: codec_par.h:177
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:387
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
AVPacket * pkt
Definition: movenc.c:59