FFmpeg
iv8.c
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1 /*
2  * Copyright (c) 2009 Michael Niedermayer
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "avformat.h"
22 #include "internal.h"
23 
24 
25 static int probe(const AVProbeData *p)
26 {
27  // the single file I have starts with that, I do not know if others do, too
28  if( p->buf[0] == 1
29  && p->buf[1] == 1
30  && p->buf[2] == 3
31  && p->buf[3] == 0xB8
32  && p->buf[4] == 0x80
33  && p->buf[5] == 0x60
34  )
35  return AVPROBE_SCORE_MAX-2;
36 
37  return 0;
38 }
39 
41 {
42  AVStream *st;
43 
44  st = avformat_new_stream(s, NULL);
45  if (!st)
46  return AVERROR(ENOMEM);
47 
51  avpriv_set_pts_info(st, 64, 1, 90000);
52 
53  return 0;
54 
55 }
56 
58 {
59  int ret, size, pts, type, flags;
60  int first_pkt = 0;
61  int frame_complete = 0;
62 
63  while (!frame_complete) {
64 
65  type = avio_rb16(s->pb); // 257 or 258
66  size = avio_rb16(s->pb);
67  flags = avio_rb16(s->pb); //some flags, 0x80 indicates end of frame
68  avio_rb16(s->pb); //packet number
69  pts = avio_rb32(s->pb);
70  avio_rb32(s->pb); //6A 13 E3 88
71 
72  frame_complete = flags & 0x80;
73 
74  size -= 12;
75  if (size < 1)
76  return -1;
77 
78  if (type == 258) {
79  avio_skip(s->pb, size);
80  frame_complete = 0;
81  continue;
82  }
83 
84  if (!first_pkt) {
85  ret = av_get_packet(s->pb, pkt, size);
86  if (ret < 0)
87  return ret;
88  first_pkt = 1;
89  pkt->pts = pts;
90  pkt->pos -= 16;
91  } else {
92  ret = av_append_packet(s->pb, pkt, size);
93  if (ret < 0) {
94  av_log(s, AV_LOG_ERROR, "failed to grow packet\n");
95  return ret;
96  }
97  }
98  if (ret < size) {
99  av_log(s, AV_LOG_ERROR, "Truncated packet! Read %d of %d bytes\n",
100  ret, size);
102  break;
103  }
104  }
105  pkt->stream_index = 0;
106 
107  return 0;
108 }
109 
111  .name = "iv8",
112  .long_name = NULL_IF_CONFIG_SMALL("IndigoVision 8000 video"),
113  .read_probe = probe,
114  .read_header = read_header,
115  .read_packet = read_packet,
116  .flags = AVFMT_GENERIC_INDEX,
117 };
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:724
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
read_header
static int read_header(AVFormatContext *s)
Definition: iv8.c:40
AV_CODEC_ID_MPEG4
@ AV_CODEC_ID_MPEG4
Definition: codec_id.h:62
probe
static int probe(const AVProbeData *p)
Definition: iv8.c:25
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:426
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
pts
static int64_t pts
Definition: transcode_aac.c:653
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:773
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:626
AV_PKT_FLAG_CORRUPT
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:426
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
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: iv8.c:57
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:399
AVFormatContext
Format I/O context.
Definition: avformat.h:1097
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:992
NULL
#define NULL
Definition: coverity.c:32
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
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
size
int size
Definition: twinvq_data.h:10344
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:379
ff_iv8_demuxer
const AVInputFormat ff_iv8_demuxer
Definition: iv8.c:110
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:366
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:196
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:845
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:758
av_append_packet
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size)
Read data and append it to the current content of the AVPacket.
Definition: utils.c:212
avformat.h
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: utils.c:1146
AVPacket::stream_index
int stream_index
Definition: packet.h:375
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:333
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
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
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:393
AVSTREAM_PARSE_FULL
@ AVSTREAM_PARSE_FULL
full parsing and repack
Definition: avformat.h:768
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28