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/*
* Copyright (C) 2008 the xine project
*
* This file is part of xine, a free video player.
*
* xine 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.
*
* xine 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, USA
*/
static inline void demux_real_sipro_swap (char buffer[], int bs)
{
/* bs = nybbles per subpacket */
static const unsigned char sipr_swaps[38][2] = {
{0, 63}, {1, 22}, {2, 44}, {3, 90}, {5, 81}, {7, 31}, {8, 86}, {9, 58},
{10, 36}, {12, 68}, {13, 39}, {14, 73}, {15, 53}, {16, 69}, {17, 57},
{19, 88}, {20, 34}, {21, 71}, {24, 46}, {25, 94}, {26, 54}, {28, 75},
{29, 50}, {32, 70}, {33, 92}, {35, 74}, {38, 85}, {40, 56}, {42, 87},
{43, 65}, {45, 59}, {48, 79}, {49, 93}, {51, 89}, {55, 95}, {61, 76},
{67, 83}, {77, 80}
};
int n;
for (n = 0; n < 38; ++n)
{
int j;
int i = bs * sipr_swaps[n][0];
int o = bs * sipr_swaps[n][1];
/* swap nibbles of block 'i' with 'o' TODO: optimize */
for (j = 0; j < bs; ++j)
{
int x = (i & 1) ? (buffer[i >> 1] >> 4) : (buffer[i >> 1] & 0x0F);
int y = (o & 1) ? (buffer[o >> 1] >> 4) : (buffer[o >> 1] & 0x0F);
if (o & 1)
buffer[o >> 1] = (buffer[o >> 1] & 0x0F) | (x << 4);
else
buffer[o >> 1] = (buffer[o >> 1] & 0xF0) | x;
if (i & 1)
buffer[i >> 1] = (buffer[i >> 1] & 0x0F) | (y << 4);
else
buffer[i >> 1] = (buffer[i >> 1] & 0xF0) | y;
++i;
++o;
}
}
}
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