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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 "startcode.h" |
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#include "config.h" |
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1207539 |
int ff_startcode_find_candidate_c(const uint8_t *buf, int size) |
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{ |
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1207539 |
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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✓✓ |
21870567 |
while (i < size && |
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21846634 |
!((~*(const uint64_t *)(buf + i) & |
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✓✓ |
21846634 |
(*(const uint64_t *)(buf + i) - 0x0101010101010101ULL)) & |
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0x8080808080808080ULL)) |
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20663028 |
i += 8; |
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#else |
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while (i < size && |
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!((~*(const uint32_t *)(buf + i) & |
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(*(const uint32_t *)(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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✓✓ |
5046399 |
for (; i < size; i++) |
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✓✓ |
4889096 |
if (!buf[i]) |
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1050236 |
break; |
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1207539 |
return i; |
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} |