openjpeg/libopenjpeg/mct.c

135 lines
3.5 KiB
C

/*
* Copyright (c) 2001-2002, David Janssens
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "mct.h"
#include "fix.h"
/* <summary> */
/* This table contains the norms of the basis function of the reversible MCT. */
/* </summary> */
double mct_norms[3] = { 1.732, .8292, .8292 };
/* <summary> */
/* This table contains the norms of the basis function of the irreversible MCT. */
/* </summary> */
double mct_norms_real[3] = { 1.732, 1.805, 1.573 };
/* <summary> */
/* Foward reversible MCT. */
/* </summary> */
void mct_encode(int *c0, int *c1, int *c2, int n)
{
int i;
for (i = 0; i < n; i++) {
int r, g, b, y, u, v;
r = c0[i];
g = c1[i];
b = c2[i];
y = (r + (g << 1) + b) >> 2;
u = b - g;
v = r - g;
c0[i] = y;
c1[i] = u;
c2[i] = v;
}
}
/* <summary> */
/* Inverse reversible MCT. */
/* </summary> */
void mct_decode(int *c0, int *c1, int *c2, int n)
{
int i;
for (i = 0; i < n; i++) {
int y, u, v, r, g, b;
y = c0[i];
u = c1[i];
v = c2[i];
g = y - ((u + v) >> 2);
r = v + g;
b = u + g;
c0[i] = r;
c1[i] = g;
c2[i] = b;
}
}
/* <summary> */
/* Get norm of basis function of reversible MCT. */
/* </summary> */
double mct_getnorm(int compno)
{
return mct_norms[compno];
}
/* <summary> */
/* Foward irreversible MCT. */
/* </summary> */
void mct_encode_real(int *c0, int *c1, int *c2, int n)
{
int i;
for (i = 0; i < n; i++) {
int r, g, b, y, u, v;
r = c0[i];
g = c1[i];
b = c2[i];
y = fix_mul(r, 2449) + fix_mul(g, 4809) + fix_mul(b, 934);
u = -fix_mul(r, 1382) - fix_mul(g, 2714) + fix_mul(b, 4096);
v = fix_mul(r, 4096) - fix_mul(g, 3430) - fix_mul(b, 666);
c0[i] = y;
c1[i] = u;
c2[i] = v;
}
}
/* <summary> */
/* Inverse irreversible MCT. */
/* </summary> */
void mct_decode_real(int *c0, int *c1, int *c2, int n)
{
int i;
for (i = 0; i < n; i++) {
int y, u, v, r, g, b;
y = c0[i];
u = c1[i];
v = c2[i];
r = y + fix_mul(v, 11485);
g = y - fix_mul(u, 2819) - fix_mul(v, 5850);
b = y + fix_mul(u, 14516);
c0[i] = r;
c1[i] = g;
c2[i] = b;
}
}
/* <summary> */
/* Get norm of basis function of irreversible MCT. */
/* </summary> */
double mct_getnorm_real(int compno)
{
return mct_norms_real[compno];
}