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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
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  */
22 #include "libavutil/intreadwrite.h"
23 #include "libavcodec/bytestream.h"
25 #include "avformat.h"
26 #include "internal.h"
28 static int hca_probe(const AVProbeData *p)
29 {
30  if (AV_RL32(p->buf) != MKTAG('H', 'C', 'A', 0))
31  return 0;
33  if (AV_RL32(p->buf + 8) != MKTAG('f', 'm', 't', 0))
34  return 0;
36  return AVPROBE_SCORE_MAX / 3;
37 }
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;
51  avio_skip(pb, 4);
52  version = avio_rb16(pb);
54  s->internal->data_offset = avio_rb16(pb);
55  if (s->internal->data_offset <= 8)
58  st = avformat_new_stream(s, NULL);
59  if (!st)
60  return AVERROR(ENOMEM);
62  par = st->codecpar;
63  ret = ff_alloc_extradata(par, s->internal->data_offset);
64  if (ret < 0)
65  return ret;
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);
74  bytestream2_init(&gb, par->extradata + 8, par->extradata_size - 8);
76  if (bytestream2_get_le32(&gb) != MKTAG('f', 'm', 't', 0))
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 {
93  }
95  if (block_size < 8)
97  par->block_align = block_size;
98  st->duration = 1024 * block_count;
100  avio_seek(pb, s->internal->data_offset, SEEK_SET);
101  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
103  return 0;
104 }
107 {
108  AVCodecParameters *par = s->streams[0]->codecpar;
109  int ret;
111  ret = av_get_packet(s->pb, pkt, par->block_align);
112  pkt->duration = 1024;
113  return ret;
114 }
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 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
Invalid data found when processing input.
Definition: error.h:59
Definition: libkvazaar.c:320
AVInputFormat ff_hca_demuxer
Definition: hca.c:116
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:4999
int64_t data_offset
offset of the first packet
Definition: internal.h:80
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1714
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
AVPacket * pkt
Definition: movenc.c:59
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:766
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
Format I/O context.
Definition: avformat.h:1247
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:387
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4553
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1315
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 AV_WB16(p, v)
Definition: intreadwrite.h:405
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:117
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
static int hca_probe(const AVProbeData *p)
Definition: hca.c:28
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
int block_align
Audio only.
Definition: codec_par.h:177
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:3368
static int hca_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: hca.c:106
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:884
AVIOContext * pb
I/O context.
Definition: avformat.h:1289
Use generic index building code.
Definition: avformat.h:463
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
static int hca_read_header(AVFormatContext *s)
Definition: hca.c:39
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:933
int sample_rate
Audio only.
Definition: codec_par.h:170
maximum score
Definition: avformat.h:453
Main libavformat public API header.
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
int channels
Audio only.
Definition: codec_par.h:166
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1049
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
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
#define MKTAG(a, b, c, d)
Definition: common.h:478
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:91
This structure stores compressed data.
Definition: packet.h:346
#define AV_WL32(p, v)
Definition: intreadwrite.h:426