32 lines
1.2 KiB
C
32 lines
1.2 KiB
C
/*
|
|
* Copyright 2003-2018 The Music Player Daemon Project
|
|
* http://www.musicpd.org
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*/
|
|
|
|
#include "bit_reverse.h"
|
|
|
|
/**
|
|
* @see http://graphics.stanford.edu/~seander/bithacks.html#BitReverseTable
|
|
*/
|
|
const uint8_t bit_reverse_table[256] =
|
|
{
|
|
#define R2(n) n, n + 2*64, n + 1*64, n + 3*64
|
|
#define R4(n) R2(n), R2(n + 2*16), R2(n + 1*16), R2(n + 3*16)
|
|
#define R6(n) R4(n), R4(n + 2*4 ), R4(n + 1*4 ), R4(n + 3*4 )
|
|
R6(0), R6(2), R6(1), R6(3)
|
|
};
|