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/*
* $Id: dc_level.c,v 1.11 2010/02/05 23:50:22 simakov Exp $
*
* EPSILON - wavelet image compression library.
* Copyright (C) 2006,2007,2010 Alexander Simakov, <xander@entropyware.info>
*
* This file is part of EPSILON
*
* EPSILON is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* EPSILON 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with EPSILON. If not, see <http://www.gnu.org/licenses/>.
*
* http://epsilon-project.sourceforge.net
*/
#include <common.h>
#include <dc_level.h>
coeff_t dc_level_shift(coeff_t **channel, int width, int height)
{
int i, j;
coeff_t average = 0.0;
for (i = 0; i < height; i++) {
for (j = 0; j < width; j++) {
average += channel[i][j];
}
}
average = average / (width * height);
for (i = 0; i < height; i++) {
for (j = 0; j < width; j++) {
channel[i][j] -= average;
}
}
return average;
}
void dc_level_unshift(coeff_t **channel, coeff_t average, int width, int height)
{
int i, j;
for (i = 0; i < height; i++) {
for (j = 0; j < width; j++) {
channel[i][j] += average;
}
}
}
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