FFmpeg  2.1.1
dfa.c
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1 /*
2  * Chronomaster DFA Format Demuxer
3  * Copyright (c) 2011 Konstantin Shishkov
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 dfa_probe(AVProbeData *p)
27 {
28  if (p->buf_size < 4 || AV_RL32(p->buf) != MKTAG('D', 'F', 'I', 'A'))
29  return 0;
30 
31  return AVPROBE_SCORE_MAX;
32 }
33 
35 {
36  AVIOContext *pb = s->pb;
37  AVStream *st;
38  int frames;
39  int version;
40  uint32_t mspf;
41 
42  if (avio_rl32(pb) != MKTAG('D', 'F', 'I', 'A')) {
43  av_log(s, AV_LOG_ERROR, "Invalid magic for DFA\n");
44  return AVERROR_INVALIDDATA;
45  }
46 
47  version = avio_rl16(pb);
48  frames = avio_rl16(pb);
49 
50  st = avformat_new_stream(s, NULL);
51  if (!st)
52  return AVERROR(ENOMEM);
53 
56  st->codec->width = avio_rl16(pb);
57  st->codec->height = avio_rl16(pb);
58  mspf = avio_rl32(pb);
59  if (!mspf) {
60  av_log(s, AV_LOG_WARNING, "Zero FPS reported, defaulting to 10\n");
61  mspf = 100;
62  }
63  avpriv_set_pts_info(st, 24, mspf, 1000);
64  avio_skip(pb, 128 - 16); // padding
65  st->duration = frames;
66 
67  if (ff_alloc_extradata(st->codec, 2))
68  return AVERROR(ENOMEM);
69  AV_WL16(st->codec->extradata, version);
70  if (version == 0x100)
71  st->sample_aspect_ratio = (AVRational){2, 1};
72 
73  return 0;
74 }
75 
77 {
78  AVIOContext *pb = s->pb;
79  uint32_t frame_size;
80  int ret, first = 1;
81 
82  if (pb->eof_reached)
83  return AVERROR_EOF;
84 
85  if (av_get_packet(pb, pkt, 12) != 12)
86  return AVERROR(EIO);
87  while (!pb->eof_reached) {
88  if (!first) {
89  ret = av_append_packet(pb, pkt, 12);
90  if (ret < 0) {
91  av_free_packet(pkt);
92  return ret;
93  }
94  } else
95  first = 0;
96  frame_size = AV_RL32(pkt->data + pkt->size - 8);
97  if (frame_size > INT_MAX - 4) {
98  av_log(s, AV_LOG_ERROR, "Too large chunk size: %d\n", frame_size);
99  return AVERROR(EIO);
100  }
101  if (AV_RL32(pkt->data + pkt->size - 12) == MKTAG('E', 'O', 'F', 'R')) {
102  if (frame_size) {
103  av_log(s, AV_LOG_WARNING, "skipping %d bytes of end-of-frame marker chunk\n",
104  frame_size);
105  avio_skip(pb, frame_size);
106  }
107  return 0;
108  }
109  ret = av_append_packet(pb, pkt, frame_size);
110  if (ret < 0) {
111  av_free_packet(pkt);
112  return ret;
113  }
114  }
115 
116  return 0;
117 }
118 
120  .name = "dfa",
121  .long_name = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
122  .read_probe = dfa_probe,
123  .read_header = dfa_read_header,
124  .read_packet = dfa_read_packet,
125  .flags = AVFMT_GENERIC_INDEX,
126 };
const char * s
Definition: avisynth_c.h:668
Bytestream IO Context.
Definition: avio.h:68
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:279
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:478
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: avcodec.h:4153
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:3922
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:686
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:733
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:593
int size
Definition: avcodec.h:1064
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
static int dfa_read_header(AVFormatContext *s)
Definition: dfa.c:34
int version
Definition: avisynth_c.h:666
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1254
Format I/O context.
Definition: avformat.h:968
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:336
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3348
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:200
static const uint8_t frame_size[4]
Definition: g723_1_data.h:58
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: avcodec.h:4147
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:577
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:355
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:337
ret
Definition: avfilter.c:961
int width
picture width / height.
Definition: avcodec.h:1314
Stream structure.
Definition: avformat.h:667
#define AV_WL16(p, darg)
Definition: intreadwrite.h:250
enum AVMediaType codec_type
Definition: avcodec.h:1154
enum AVCodecID codec_id
Definition: avcodec.h:1157
int ff_alloc_extradata(AVCodecContext *avctx, int size)
Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:2690
AVIOContext * pb
I/O context.
Definition: avformat.h:1001
#define MKTAG(a, b, c, d)
rational number numerator/denominator
Definition: rational.h:43
uint8_t * data
Definition: avcodec.h:1063
AVInputFormat ff_dfa_demuxer
Definition: dfa.c:119
This structure contains the data a format has to probe a file.
Definition: avformat.h:334
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:256
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:210
#define AVERROR_EOF
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:342
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:720
static int dfa_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dfa.c:76
Main libavformat public API header.
static int dfa_probe(AVProbeData *p)
Definition: dfa.c:26
#define AVERROR_INVALIDDATA
int eof_reached
true if eof reached
Definition: avio.h:96
#define AV_RL32(x)
Definition: intreadwrite.h:275
#define AVERROR(e)
static AVPacket pkt
Definition: demuxing.c:52
This structure stores compressed data.
Definition: avcodec.h:1040