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Diffstat (limited to 'openjdk/gnu/java/awt/color/ToneReproductionCurve.java')
-rw-r--r-- | openjdk/gnu/java/awt/color/ToneReproductionCurve.java | 177 |
1 files changed, 0 insertions, 177 deletions
diff --git a/openjdk/gnu/java/awt/color/ToneReproductionCurve.java b/openjdk/gnu/java/awt/color/ToneReproductionCurve.java deleted file mode 100644 index 208e1688..00000000 --- a/openjdk/gnu/java/awt/color/ToneReproductionCurve.java +++ /dev/null @@ -1,177 +0,0 @@ -/* ToneReproductionCurve.java -- Representation of an ICC 'curv' type TRC - Copyright (C) 2004 Free Software Foundation - -This file is part of GNU Classpath. - -GNU Classpath is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. - -GNU Classpath 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 for more details. - -You should have received a copy of the GNU General Public License -along with GNU Classpath; see the file COPYING. If not, write to the -Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA -02110-1301 USA. - -Linking this library statically or dynamically with other modules is -making a combined work based on this library. Thus, the terms and -conditions of the GNU General Public License cover the whole -combination. - -As a special exception, the copyright holders of this library give you -permission to link this library with independent modules to produce an -executable, regardless of the license terms of these independent -modules, and to copy and distribute the resulting executable under -terms of your choice, provided that you also meet, for each linked -independent module, the terms and conditions of the license of that -module. An independent module is a module which is not derived from -or based on this library. If you modify this library, you may extend -this exception to your version of the library, but you are not -obligated to do so. If you do not wish to do so, delete this -exception statement from your version. */ - -package gnu.java.awt.color; - - -/** - * ToneReproductionCurve - TRCs are used to describe RGB - * and Grayscale profiles. The TRC is essentially the gamma - * function of the color space. - * - * For example, Apple RGB has a gamma of 1.8, most monitors are ~2.2, - * sRGB is 2.4 with a small linear part near 0. - * Linear spaces are of course 1.0. - * (The exact function is implemented in SrgbConverter) - * - * The ICC specification allows the TRC to be described as a single - * Gamma value, where the function is thus out = in**gamma. - * Alternatively, the gamma function may be represented by a lookup table - * of values, in which case linear interpolation is used. - * - * @author Sven de Marothy - */ -public class ToneReproductionCurve -{ - private float[] trc; - private float gamma; - private float[] reverseTrc; - - /** - * Constructs a TRC from a gamma values - */ - public ToneReproductionCurve(float gamma) - { - trc = null; - reverseTrc = null; - this.gamma = gamma; - } - - /** - * Constructs a TRC from a set of float values - */ - public ToneReproductionCurve(float[] trcValues) - { - trc = new float[trcValues.length]; - System.arraycopy(trcValues, 0, trc, 0, trcValues.length); - setupReverseTrc(); - } - - /** - * Constructs a TRC from a set of short values normalized to - * the 0-65535 range (as in the ICC profile file). - * (Note the values are treated as unsigned) - */ - public ToneReproductionCurve(short[] trcValues) - { - trc = new float[trcValues.length]; - for (int i = 0; i < trcValues.length; i++) - trc[i] = (float) ((int) trcValues[i] & (0xFFFF)) / 65535.0f; - setupReverseTrc(); - } - - /** - * Performs a TRC lookup - */ - public float lookup(float in) - { - float out; - - if (trc == null) - { - if (in == 0f) - return 0.0f; - return (float) Math.exp(gamma * Math.log(in)); - } - else - { - double alpha = in * (trc.length - 1); - int index = (int) Math.floor(alpha); - alpha = alpha - (double) index; - if (index >= trc.length - 1) - return trc[trc.length - 1]; - if (index <= 0) - return trc[0]; - out = (float) (trc[index] * (1.0 - alpha) + trc[index + 1] * alpha); - } - return out; - } - - /** - * Performs an reverse lookup - */ - public float reverseLookup(float in) - { - float out; - - if (trc == null) - { - if (in == 0f) - return 0.0f; - return (float) Math.exp((1.0 / gamma) * Math.log(in)); - } - else - { - double alpha = in * (reverseTrc.length - 1); - int index = (int) Math.floor(alpha); - alpha = alpha - (double) index; - if (index >= reverseTrc.length - 1) - return reverseTrc[reverseTrc.length - 1]; - if (index <= 0) - return reverseTrc[0]; - out = (float) (reverseTrc[index] * (1.0 - alpha) - + reverseTrc[index + 1] * alpha); - } - return out; - } - - /** - * Calculates a reverse-lookup table. - * We use a whopping 10,000 entries.. This is should be more than any - * real-life TRC table (typically around 256-1024) so we won't be losing - * any precision. - * - * This will of course generate completely invalid results if the curve - * is not monotonic and invertable. But what's the alternative? - */ - public void setupReverseTrc() - { - reverseTrc = new float[10000]; - int j = 0; - for (int i = 0; i < 10000; i++) - { - float n = ((float) i) / 10000f; - while (trc[j + 1] < n && j < trc.length - 2) - j++; - - if (j == trc.length - 2) - reverseTrc[i] = trc[trc.length - 1]; - else - reverseTrc[i] = (j + (n - trc[j]) / (trc[j + 1] - trc[j])) / ((float) trc.length); - } - } -} |