Libav
assdec.c
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1 /*
2  * SSA/ASS decoder
3  * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org>
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <string.h>
23 
24 #include "avcodec.h"
25 #include "ass.h"
26 #include "libavutil/internal.h"
27 #include "libavutil/mem.h"
28 
30 {
31  avctx->subtitle_header = av_malloc(avctx->extradata_size);
32  if (!avctx->extradata)
33  return AVERROR(ENOMEM);
34  memcpy(avctx->subtitle_header, avctx->extradata, avctx->extradata_size);
35  avctx->subtitle_header_size = avctx->extradata_size;
36  return 0;
37 }
38 
39 static int ass_decode_frame(AVCodecContext *avctx, void *data, int *got_sub_ptr,
40  AVPacket *avpkt)
41 {
42  const char *ptr = avpkt->data;
43  int len, size = avpkt->size;
44 
45  ff_ass_init(data);
46 
47  while (size > 0) {
48  len = ff_ass_add_rect(data, ptr, 0, 0/* FIXME: duration */, 1);
49  if (len < 0)
50  return len;
51  ptr += len;
52  size -= len;
53  }
54 
55  *got_sub_ptr = avpkt->size > 0;
56  return avpkt->size;
57 }
58 
60  .name = "ass",
61  .long_name = NULL_IF_CONFIG_SMALL("SSA (SubStation Alpha) subtitle"),
62  .type = AVMEDIA_TYPE_SUBTITLE,
63  .id = AV_CODEC_ID_SSA,
64  .init = ass_decode_init,
65  .decode = ass_decode_frame,
66 };
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
int size
memory handling functions
int size
Definition: avcodec.h:968
AVCodec.
Definition: avcodec.h:2790
static av_cold int ass_decode_init(AVCodecContext *avctx)
Definition: assdec.c:29
#define av_cold
Definition: attributes.h:66
int subtitle_header_size
Definition: avcodec.h:2732
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1158
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:967
#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:150
void ff_ass_init(AVSubtitle *sub)
Initialize an AVSubtitle structure for use with ff_ass_add_rect().
Definition: ass.c:82
const char * name
Name of the codec implementation.
Definition: avcodec.h:2797
common internal API header
AVCodec ff_ass_decoder
Definition: assdec.c:59
static int ass_decode_frame(AVCodecContext *avctx, void *data, int *got_sub_ptr, AVPacket *avpkt)
Definition: assdec.c:39
Libavcodec external API header.
main external API structure.
Definition: avcodec.h:1044
int extradata_size
Definition: avcodec.h:1159
int len
int ff_ass_add_rect(AVSubtitle *sub, const char *dialog, int ts_start, int ts_end, int raw)
Add an ASS dialog line to an AVSubtitle as a new AVSubtitleRect.
Definition: ass.c:96
This structure stores compressed data.
Definition: avcodec.h:944
uint8_t * subtitle_header
Header containing style information for text subtitles.
Definition: avcodec.h:2731