FFmpeg
libavcodec
startcode.c
Go to the documentation of this file.
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/*
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* Copyright (c) 2003-2010 Michael Niedermayer <michaelni@gmx.at>
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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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* Accelerated start code search function for start codes common to
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* MPEG-1/2/4 video, VC-1, H.264/5
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* @author Michael Niedermayer <michaelni@gmx.at>
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*/
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#include "
libavutil/intreadwrite.h
"
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#include "
startcode.h
"
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#include "config.h"
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int
ff_startcode_find_candidate_c
(
const
uint8_t *buf,
int
size
)
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{
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int
i
= 0;
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#if HAVE_FAST_UNALIGNED
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/* we check i < size instead of i + 3 / 7 because it is
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* simpler and there must be AV_INPUT_BUFFER_PADDING_SIZE
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* bytes at the end.
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*/
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#if HAVE_FAST_64BIT
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while
(
i
<
size
&&
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!((~
AV_RN64
(buf +
i
) &
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(
AV_RN64
(buf +
i
) - 0x0101010101010101ULL)) &
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0x8080808080808080ULL))
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i
+= 8;
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#else
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while
(
i
<
size
&&
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!((~
AV_RN32
(buf +
i
) &
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(
AV_RN32
(buf +
i
) - 0x01010101U)) &
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0x80808080U))
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i
+= 4;
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#endif
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#endif
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for
(;
i
<
size
;
i
++)
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if
(!buf[
i
])
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break
;
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return
i
;
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}
AV_RN64
#define AV_RN64(p)
Definition:
intreadwrite.h:364
ff_startcode_find_candidate_c
int ff_startcode_find_candidate_c(const uint8_t *buf, int size)
Definition:
startcode.c:32
intreadwrite.h
AV_RN32
#define AV_RN32(p)
Definition:
intreadwrite.h:360
startcode.h
size
int size
Definition:
twinvq_data.h:10344
i
#define i(width, name, range_min, range_max)
Definition:
cbs_h2645.c:256
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