| /* |
| * 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]; |
| } |