FFmpeg
aixdec.c
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1 /*
2  * AIX demuxer
3  * Copyright (c) 2016 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 "avformat.h"
24 #include "internal.h"
25 
26 static int aix_probe(const AVProbeData *p)
27 {
28  if (AV_RL32(p->buf) != MKTAG('A','I','X','F') ||
29  AV_RB32(p->buf + 8) != 0x01000014 ||
30  AV_RB32(p->buf + 12) != 0x00000800)
31  return 0;
32 
33  return AVPROBE_SCORE_MAX;
34 }
35 
37 {
38  unsigned nb_streams, first_offset, nb_segments;
39  unsigned stream_list_offset;
40  unsigned segment_list_offset = 0x20;
41  unsigned segment_list_entry_size = 0x10;
42  unsigned size;
43  int i;
44 
45  avio_skip(s->pb, 4);
46  first_offset = avio_rb32(s->pb) + 8;
47  avio_skip(s->pb, 16);
48  nb_segments = avio_rb16(s->pb);
49  if (nb_segments == 0)
50  return AVERROR_INVALIDDATA;
51  stream_list_offset = segment_list_offset + segment_list_entry_size * nb_segments + 0x10;
52  if (stream_list_offset >= first_offset)
53  return AVERROR_INVALIDDATA;
54  avio_seek(s->pb, stream_list_offset, SEEK_SET);
55  nb_streams = avio_r8(s->pb);
56  if (nb_streams == 0)
57  return AVERROR_INVALIDDATA;
58  avio_skip(s->pb, 7);
59  for (i = 0; i < nb_streams; i++) {
61 
62  if (!st)
63  return AVERROR(ENOMEM);
66  st->codecpar->sample_rate = avio_rb32(s->pb);
67  st->codecpar->channels = avio_r8(s->pb);
68  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
69  avio_skip(s->pb, 3);
70  }
71 
72  avio_seek(s->pb, first_offset, SEEK_SET);
73  for (i = 0; i < nb_streams; i++) {
74  if (avio_rl32(s->pb) != MKTAG('A','I','X','P'))
75  return AVERROR_INVALIDDATA;
76  size = avio_rb32(s->pb);
77  if (size <= 8)
78  return AVERROR_INVALIDDATA;
79  avio_skip(s->pb, 8);
80  ff_get_extradata(s, s->streams[i]->codecpar, s->pb, size - 8);
81  }
82 
83  return 0;
84 }
85 
87 {
88  unsigned size, index, duration, chunk;
89  int64_t pos;
90  int sequence, ret, i;
91 
92  pos = avio_tell(s->pb);
93  if (avio_feof(s->pb))
94  return AVERROR_EOF;
95  chunk = avio_rl32(s->pb);
96  size = avio_rb32(s->pb);
97  if (chunk == MKTAG('A','I','X','E')) {
98  avio_skip(s->pb, size);
99  for (i = 0; i < s->nb_streams; i++) {
100  if (avio_feof(s->pb))
101  return AVERROR_EOF;
102  chunk = avio_rl32(s->pb);
103  size = avio_rb32(s->pb);
104  avio_skip(s->pb, size);
105  }
106  pos = avio_tell(s->pb);
107  chunk = avio_rl32(s->pb);
108  size = avio_rb32(s->pb);
109  }
110 
111  if (chunk != MKTAG('A','I','X','P'))
112  return AVERROR_INVALIDDATA;
113  if (size <= 8)
114  return AVERROR_INVALIDDATA;
115  index = avio_r8(s->pb);
116  if (avio_r8(s->pb) != s->nb_streams || index >= s->nb_streams)
117  return AVERROR_INVALIDDATA;
118  duration = avio_rb16(s->pb);
119  sequence = avio_rb32(s->pb);
120  if (sequence < 0) {
121  avio_skip(s->pb, size - 8);
122  return 0;
123  }
124 
125  ret = av_get_packet(s->pb, pkt, size - 8);
126  pkt->stream_index = index;
127  pkt->duration = duration;
128  pkt->pos = pos;
129  return ret;
130 }
131 
133  .name = "aix",
134  .long_name = NULL_IF_CONFIG_SMALL("CRI AIX"),
135  .read_probe = aix_probe,
136  .read_header = aix_read_header,
137  .read_packet = aix_read_packet,
138  .extensions = "aix",
139  .flags = AVFMT_GENERIC_INDEX,
140 };
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1500
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:4929
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:334
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:788
Format I/O context.
Definition: avformat.h:1358
static int nb_streams
Definition: ffprobe.c:280
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:803
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1498
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
static int aix_probe(const AVProbeData *p)
Definition: aixdec.c:26
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:87
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
int64_t duration
Definition: movenc.c:63
static int aix_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: aixdec.c:86
#define AVERROR_EOF
End of file.
Definition: error.h:55
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
ptrdiff_t size
Definition: opengl_enc.c:100
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:772
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
AVInputFormat ff_aix_demuxer
Definition: aixdec.c:132
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:641
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1414
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:881
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
int index
Definition: gxfenc.c:89
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
int sample_rate
Audio only.
Definition: avcodec.h:4078
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
Main libavformat public API header.
int ff_get_extradata(AVFormatContext *s, 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: utils.c:3339
static int aix_read_header(AVFormatContext *s)
Definition: aixdec.c:36
int channels
Audio only.
Definition: avcodec.h:4074
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:1028
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:361
int stream_index
Definition: avcodec.h:1482
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:366
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1457