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/*
* Copyright (c) 1996, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* This file contains macro definitions for the Encoding category of
* the macros used by the generic scaleloop function.
*
* This implementation uses an ordered dithering error matrix with
* signed error adjustments to produce a moderately high quality
* version of an image with only an 8-bit (or less) RGB colormap and
* a "closest color" lookup table. The ordered dithering technique
* does not rely on the order in which the pixels are processed so
* this file can be used in cases where the ImageProducer has not
* specified the TopDownLeftRight delivery hint. The ordered dither
* technique is also much faster than the Floyd-Steinberg error diffusion
* algorithm so this implementation would also be appropriate for
* cases where performance is critical such as the processing of a
* video stream.
*
* This file can be used to provide the default implementation of the
* Encoding macros for RGB colormapped displays.
*/
/*
* These definitions vector the standard macro names to the "Color"
* versions of those macros only if the "DitherDeclared" keyword has
* not yet been defined elsewhere. The "DitherDeclared" keyword is
* also defined here to claim ownership of the primary implementation
* even though this file does not rely on the definitions in any other
* files.
*/
#ifndef DitherDeclared
#define DitherDeclared
#define DeclareDitherVars DeclareAllColorDitherVars
#define InitDither InitColorDither
#define StartDitherLine StartColorDitherLine
#define DitherPixel ColorDitherPixel
#define DitherBufComplete ColorDitherBufComplete
#endif
#define DeclareAllColorDitherVars \
DeclareColorDitherVars \
int relx, rely;
#define DeclareColorDitherVars \
extern sgn_ordered_dither_array img_oda_red; \
extern sgn_ordered_dither_array img_oda_green; \
extern sgn_ordered_dither_array img_oda_blue;
#define InitColorDither(cvdata, clrdata, dstTW) \
do {} while (0)
#define StartColorDitherLine(cvdata, dstX1, dstY) \
do { \
relx = dstX1 & 7; \
rely = dstY & 7; \
} while (0)
#define ColorDitherPixel(dstX, dstY, pixel, red, green, blue) \
do { \
red += img_oda_red[relx][rely]; \
red = ComponentBound(red); \
green += img_oda_green[relx][rely]; \
green = ComponentBound(green); \
blue += img_oda_blue[relx][rely]; \
blue = ComponentBound(blue); \
pixel = ColorCubeOrdMapSgn(red, green, blue); \
relx = (relx + 1) & 7; \
} while (0)
#define ColorDitherBufComplete(cvdata, dstX1) \
do {} while (0)