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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 <inttypes.h>
23 
24 #include "libavutil/intreadwrite.h"
25 #include "avformat.h"
26 #include "internal.h"
27 
28 static int dfa_probe(AVProbeData *p)
29 {
30  if (p->buf_size < 4 || AV_RL32(p->buf) != MKTAG('D', 'F', 'I', 'A'))
31  return 0;
32 
33  if (AV_RL32(p->buf + 16) != 0x80)
34  return AVPROBE_SCORE_MAX / 4;
35 
36  return AVPROBE_SCORE_MAX;
37 }
38 
40 {
41  AVIOContext *pb = s->pb;
42  AVStream *st;
43  int frames;
44  int version;
45  uint32_t mspf;
46 
47  if (avio_rl32(pb) != MKTAG('D', 'F', 'I', 'A')) {
48  av_log(s, AV_LOG_ERROR, "Invalid magic for DFA\n");
49  return AVERROR_INVALIDDATA;
50  }
51 
52  version = avio_rl16(pb);
53  frames = avio_rl16(pb);
54 
55  st = avformat_new_stream(s, NULL);
56  if (!st)
57  return AVERROR(ENOMEM);
58 
61  st->codecpar->width = avio_rl16(pb);
62  st->codecpar->height = avio_rl16(pb);
63  mspf = avio_rl32(pb);
64  if (!mspf) {
65  av_log(s, AV_LOG_WARNING, "Zero FPS reported, defaulting to 10\n");
66  mspf = 100;
67  }
68  avpriv_set_pts_info(st, 24, mspf, 1000);
69  avio_skip(pb, 128 - 16); // padding
70  st->duration = frames;
71 
72  if (ff_alloc_extradata(st->codecpar, 2))
73  return AVERROR(ENOMEM);
74  AV_WL16(st->codecpar->extradata, version);
75  if (version == 0x100)
76  st->sample_aspect_ratio = (AVRational){2, 1};
77 
78  return 0;
79 }
80 
82 {
83  AVIOContext *pb = s->pb;
84  uint32_t frame_size;
85  int ret, first = 1;
86 
87  if (avio_feof(pb))
88  return AVERROR_EOF;
89 
90  if (av_get_packet(pb, pkt, 12) != 12)
91  return AVERROR(EIO);
92  while (!avio_feof(pb)) {
93  if (!first) {
94  ret = av_append_packet(pb, pkt, 12);
95  if (ret < 0) {
96  av_packet_unref(pkt);
97  return ret;
98  }
99  } else
100  first = 0;
101  frame_size = AV_RL32(pkt->data + pkt->size - 8);
102  if (frame_size > INT_MAX - 4) {
103  av_log(s, AV_LOG_ERROR, "Too large chunk size: %"PRIu32"\n", frame_size);
104  av_packet_unref(pkt);
105  return AVERROR(EIO);
106  }
107  if (AV_RL32(pkt->data + pkt->size - 12) == MKTAG('E', 'O', 'F', 'R')) {
108  if (frame_size) {
110  "skipping %"PRIu32" bytes of end-of-frame marker chunk\n",
111  frame_size);
112  avio_skip(pb, frame_size);
113  }
114  return 0;
115  }
116  ret = av_append_packet(pb, pkt, frame_size);
117  if (ret < 0) {
118  av_packet_unref(pkt);
119  return ret;
120  }
121  }
122 
123  return 0;
124 }
125 
127  .name = "dfa",
128  .long_name = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
129  .read_probe = dfa_probe,
130  .read_header = dfa_read_header,
131  .read_packet = dfa_read_packet,
132  .flags = AVFMT_GENERIC_INDEX,
133 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:147
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
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:4581
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3987
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:956
int size
Definition: avcodec.h:1608
static int dfa_read_header(AVFormatContext *s)
Definition: dfa.c:39
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:304
int version
Definition: avisynth_c.h:766
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1338
int width
Video only.
Definition: avcodec.h:4053
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4214
uint8_t * data
Definition: avcodec.h:1607
#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:289
#define av_log(a,...)
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:299
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:726
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3983
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:464
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
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:3190
int frames
Definition: movenc.c:65
Stream structure.
Definition: avformat.h:889
int frame_size
Definition: mxfenc.c:1820
AVIOContext * pb
I/O context.
Definition: avformat.h:1380
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:569
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:487
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVInputFormat ff_dfa_demuxer
Definition: dfa.c:126
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:943
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:710
Main libavformat public API header.
static int dfa_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dfa.c:81
#define AV_WL16(p, v)
Definition: intreadwrite.h:412
static int dfa_probe(AVProbeData *p)
Definition: dfa.c:28
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:4001
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:664
AVCodecParameters * codecpar
Definition: avformat.h:1241
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:328
#define MKTAG(a, b, c, d)
Definition: common.h:342
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1584