FFmpeg
libavcodec
dvdsub_parser.c
Go to the documentation of this file.
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/*
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* DVD subtitle decoding
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* Copyright (c) 2005 Fabrice Bellard
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <string.h>
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#include "
libavutil/intreadwrite.h
"
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#include "
libavutil/mem.h
"
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#include "
avcodec.h
"
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/* parser definition */
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typedef
struct
DVDSubParseContext
{
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uint8_t *
packet
;
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int
packet_len
;
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int
packet_index
;
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}
DVDSubParseContext
;
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static
int
dvdsub_parse
(
AVCodecParserContext
*
s
,
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AVCodecContext
*avctx,
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const
uint8_t **poutbuf,
int
*poutbuf_size,
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const
uint8_t *buf,
int
buf_size)
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{
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DVDSubParseContext
*pc =
s
->priv_data;
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*poutbuf = buf;
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*poutbuf_size = buf_size;
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if
(pc->
packet_index
== 0) {
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if
(buf_size < 2 || (
AV_RB16
(buf) == 0 && buf_size < 6)) {
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if
(buf_size)
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av_log
(avctx,
AV_LOG_DEBUG
,
"Parser input %d too small\n"
, buf_size);
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return
buf_size;
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}
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pc->
packet_len
=
AV_RB16
(buf);
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if
(pc->
packet_len
== 0)
/* HD-DVD subpicture packet */
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pc->
packet_len
=
AV_RB32
(buf+2);
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av_freep
(&pc->
packet
);
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if
((
unsigned
)pc->
packet_len
> INT_MAX -
AV_INPUT_BUFFER_PADDING_SIZE
) {
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av_log
(avctx,
AV_LOG_ERROR
,
"packet length %d is invalid\n"
, pc->
packet_len
);
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return
buf_size;
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}
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pc->
packet
=
av_malloc
(pc->
packet_len
+
AV_INPUT_BUFFER_PADDING_SIZE
);
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}
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if
(pc->
packet
) {
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if
(pc->
packet_index
+ buf_size <= pc->packet_len) {
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memcpy(pc->
packet
+ pc->
packet_index
, buf, buf_size);
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pc->
packet_index
+= buf_size;
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if
(pc->
packet_index
>= pc->
packet_len
) {
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*poutbuf = pc->
packet
;
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*poutbuf_size = pc->
packet_len
;
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pc->
packet_index
= 0;
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return
buf_size;
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}
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}
else
{
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/* erroneous size */
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pc->
packet_index
= 0;
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}
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}
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*poutbuf =
NULL
;
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*poutbuf_size = 0;
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return
buf_size;
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}
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static
av_cold
void
dvdsub_parse_close
(
AVCodecParserContext
*
s
)
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{
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DVDSubParseContext
*pc =
s
->priv_data;
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av_freep
(&pc->
packet
);
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}
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const
AVCodecParser
ff_dvdsub_parser
= {
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.
codec_ids
= {
AV_CODEC_ID_DVD_SUBTITLE
},
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.priv_data_size =
sizeof
(
DVDSubParseContext
),
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.parser_parse =
dvdsub_parse
,
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.parser_close =
dvdsub_parse_close
,
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};
av_malloc
#define av_malloc(s)
Definition:
tableprint_vlc.h:30
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition:
log.h:209
av_cold
#define av_cold
Definition:
attributes.h:90
dvdsub_parse
static int dvdsub_parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition:
dvdsub_parser.c:35
intreadwrite.h
s
#define s(width, name)
Definition:
cbs_vp9.c:198
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition:
log.h:230
NULL
#define NULL
Definition:
coverity.c:32
AV_CODEC_ID_DVD_SUBTITLE
@ AV_CODEC_ID_DVD_SUBTITLE
Definition:
codec_id.h:551
DVDSubParseContext::packet_index
int packet_index
Definition:
dvdsub_parser.c:32
AVCodecParser::codec_ids
int codec_ids[7]
Definition:
avcodec.h:2908
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition:
bytestream.h:96
DVDSubParseContext::packet_len
int packet_len
Definition:
dvdsub_parser.c:31
dvdsub_parse_close
static av_cold void dvdsub_parse_close(AVCodecParserContext *s)
Definition:
dvdsub_parser.c:81
ff_dvdsub_parser
const AVCodecParser ff_dvdsub_parser
Definition:
dvdsub_parser.c:87
DVDSubParseContext
Definition:
dvdsub_parser.c:29
avcodec.h
AVCodecParserContext
Definition:
avcodec.h:2748
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition:
defs.h:40
DVDSubParseContext::packet
uint8_t * packet
Definition:
dvdsub_parser.c:30
AVCodecContext
main external API structure.
Definition:
avcodec.h:451
mem.h
av_freep
#define av_freep(p)
Definition:
tableprint_vlc.h:34
AVCodecParser
Definition:
avcodec.h:2907
av_log
#define av_log(a,...)
Definition:
tableprint_vlc.h:27
AV_RB16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition:
bytestream.h:98
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