1 /*
2  * Copyright (c) 1996, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 /*
27  * This file contains utility macros used by the Floyd-Steinberg
28  * algorithms used in some of the other include files.
29  */
30 
31 #ifndef IMG_FSUTIL_H
32 #define IMG_FSUTIL_H
33 
34 #define DitherDist(ep, e1, e2, e3, ec, c)               \
35     do {                                                \
36         e3 = (ec << 1);                                 \
37         e1 = e3 + ec;                                   \
38         e2 = e3 + e1;                                   \
39         e3 += e2;                                       \
40                                                         \
41         ep[0].c += e1 >>= 4;                            \
42         ep[1].c += e2 >>= 4;                            \
43         ep[2].c += e3 >>= 4;                            \
44         ec -= e1 + e2 + e3;                             \
45     } while (0)
46 
47 #endif /* IMG_FSUTIL_H */
48