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sauce.c
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1 /*
2  * SAUCE header parser
3  * Copyright (c) 2010 Peter Ross <pross@xvid.org>
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 /**
23  * @file
24  * SAUCE header parser
25  */
26 
27 #include "libavutil/intreadwrite.h"
28 #include "libavutil/dict.h"
29 #include "avformat.h"
30 #include "sauce.h"
31 
32 int ff_sauce_read(AVFormatContext *avctx, uint64_t *fsize, int *got_width, int get_height)
33 {
34  AVIOContext *pb = avctx->pb;
35  char buf[36];
36  int datatype, filetype, t1, t2, nb_comments;
37  uint64_t start_pos = avio_size(pb) - 128;
38 
39  avio_seek(pb, start_pos, SEEK_SET);
40  if (avio_read(pb, buf, 7) != 7)
41  return -1;
42  if (memcmp(buf, "SAUCE00", 7))
43  return -1;
44 
45 #define GET_SAUCE_META(name,size) \
46  if (avio_read(pb, buf, size) == size && buf[0]) { \
47  buf[size] = 0; \
48  av_dict_set(&avctx->metadata, name, buf, 0); \
49  }
50 
51  GET_SAUCE_META("title", 35)
52  GET_SAUCE_META("artist", 20)
53  GET_SAUCE_META("publisher", 20)
54  GET_SAUCE_META("date", 8)
55  avio_skip(pb, 4);
56  datatype = avio_r8(pb);
57  filetype = avio_r8(pb);
58  t1 = avio_rl16(pb);
59  t2 = avio_rl16(pb);
60  nb_comments = avio_r8(pb);
61  avio_skip(pb, 1); /* flags */
62  avio_skip(pb, 4);
63  GET_SAUCE_META("encoder", 22);
64 
65  if (got_width && datatype && filetype) {
66  if ((datatype == 1 && filetype <=2) || (datatype == 5 && filetype == 255) || datatype == 6) {
67  if (t1) {
68  avctx->streams[0]->codec->width = t1<<3;
69  *got_width = 1;
70  }
71  if (get_height && t2)
72  avctx->streams[0]->codec->height = t2<<4;
73  } else if (datatype == 5) {
74  if (filetype) {
75  avctx->streams[0]->codec->width = (filetype == 1 ? t1 : filetype) << 4;
76  *got_width = 1;
77  }
78  if (get_height && t2)
79  avctx->streams[0]->codec->height = t2<<4;
80  }
81  }
82 
83  *fsize -= 128;
84 
85  if (nb_comments > 0) {
86  avio_seek(pb, start_pos - 64*nb_comments - 5, SEEK_SET);
87  if (avio_read(pb, buf, 5) == 5 && !memcmp(buf, "COMNT", 5)) {
88  int i;
89  char *str = av_malloc(65*nb_comments + 1);
90  *fsize -= 64*nb_comments + 5;
91  if (!str)
92  return 0;
93  for (i = 0; i < nb_comments; i++) {
94  if (avio_read(pb, str + 65*i, 64) != 64)
95  break;
96  str[65*i + 64] = '\n';
97  }
98  str[65*i] = 0;
99  av_dict_set(&avctx->metadata, "comment", str, AV_DICT_DONT_STRDUP_VAL);
100  }
101  }
102 
103  return 0;
104 }
Bytestream IO Context.
Definition: avio.h:111
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:281
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:203
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:276
Format I/O context.
Definition: avformat.h:1272
Public dictionary API.
#define av_malloc(s)
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1340
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:537
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1482
#define t1
Definition: regdef.h:29
int ff_sauce_read(AVFormatContext *avctx, uint64_t *fsize, int *got_width, int get_height)
Definition: sauce.c:32
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:528
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:861
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:78
int width
picture width / height.
Definition: avcodec.h:1414
AVIOContext * pb
I/O context.
Definition: avformat.h:1314
void * buf
Definition: avisynth_c.h:553
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:69
#define GET_SAUCE_META(name, size)
SAUCE header parser.
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:642
Main libavformat public API header.
static int get_height(const FieldMatchContext *fm, const AVFrame *f, int plane)
#define t2
Definition: regdef.h:30