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libavcodec
bmp_parser.c
Go to the documentation of this file.
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/*
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* BMP parser
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* Copyright (c) 2012 Paul B Mahol
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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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/**
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* @file
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* BMP parser
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*/
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#include "
libavutil/bswap.h
"
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#include "
libavutil/common.h
"
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#include "
parser.h
"
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typedef
struct
BMPParseContext
{
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ParseContext
pc
;
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uint32_t
fsize
;
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uint32_t
remaining_size
;
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}
BMPParseContext
;
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static
int
bmp_parse
(
AVCodecParserContext
*
s
,
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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BMPParseContext
*bpc = s->
priv_data
;
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uint64_t
state
= bpc->
pc
.
state64
;
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int
next =
END_NOT_FOUND
;
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int
i = 0;
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*poutbuf_size = 0;
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if
(buf_size == 0)
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return
0;
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if
(!bpc->
pc
.
frame_start_found
) {
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for
(; i < buf_size; i++) {
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state = (state << 8) | buf[i];
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if
((state >> 48) == ((
'B'
<< 8) |
'M'
)) {
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bpc->
fsize
=
av_bswap32
(state >> 16);
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bpc->
pc
.
frame_start_found
= 1;
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if
(bpc->
fsize
> buf_size - i + 7)
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bpc->
remaining_size
= bpc->
fsize
- buf_size + i - 7;
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else
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next = bpc->
fsize
+ i - 7;
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break
;
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}
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}
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bpc->
pc
.
state64
=
state
;
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}
else
{
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if
(bpc->
remaining_size
) {
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i =
FFMIN
(bpc->
remaining_size
, buf_size);
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bpc->
remaining_size
-= i;
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if
(bpc->
remaining_size
)
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goto
flush
;
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next = i;
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}
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}
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flush
:
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if
(
ff_combine_frame
(&bpc->
pc
, next, &buf, &buf_size) < 0)
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return
buf_size;
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bpc->
pc
.
frame_start_found
= 0;
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*poutbuf =
buf
;
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*poutbuf_size = buf_size;
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return
next;
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}
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AVCodecParser
ff_bmp_parser
= {
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.
codec_ids
= {
AV_CODEC_ID_BMP
},
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.priv_data_size =
sizeof
(
BMPParseContext
),
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.parser_parse =
bmp_parse
,
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.parser_close =
ff_parse_close
,
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};
Generated on Sun Jul 20 2014 23:05:44 for FFmpeg by
1.8.2