2 * Copyright (c) 2003-2010 Michael Niedermayer <michaelni@gmx.at>
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * Accelerated start code search function for start codes common to
24 * MPEG-1/2/4 video, VC-1, H.264/5
25 * @author Michael Niedermayer <michaelni@gmx.at>
28 #include "libavutil/intreadwrite.h"
29 #include "startcode.h"
32 int ff_startcode_find_candidate_c(const uint8_t *buf, int size)
35 #if HAVE_FAST_UNALIGNED
36 /* we check i < size instead of i + 3 / 7 because it is
37 * simpler and there must be AV_INPUT_BUFFER_PADDING_SIZE
42 !((~AV_RN64(buf + i) &
43 (AV_RN64(buf + i) - 0x0101010101010101ULL)) &
44 0x8080808080808080ULL))
48 !((~AV_RN32(buf + i) &
49 (AV_RN32(buf + i) - 0x01010101U)) &