| /* ColorLookUpTable.java -- ICC v2 CLUT |
| 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; |
| |
| import java.awt.color.ColorSpace; |
| import java.awt.color.ICC_Profile; |
| import java.nio.ByteBuffer; |
| |
| |
| /** |
| * ColorLookUpTable handles color lookups through a color lookup table, |
| * as defined in the ICC specification. |
| * Both 'mft2' and 'mft1' (8 and 16-bit) type CLUTs are handled. |
| * |
| * This will have to be updated later for ICC 4.0.0 |
| * |
| * @author Sven de Marothy |
| */ |
| public class ColorLookUpTable |
| { |
| /** |
| * CIE 1931 D50 white point (in Lab coordinates) |
| */ |
| private static float[] D50 = { 0.96422f, 1.00f, 0.82521f }; |
| |
| /** |
| * Number of input/output channels |
| */ |
| int nIn; |
| |
| /** |
| * Number of input/output channels |
| */ |
| int nOut; |
| int nInTableEntries; // Number of input table entries |
| int nOutTableEntries; // Number of output table entries |
| int gridpoints; // Number of gridpoints |
| int nClut; // This is nOut*(gridpoints**nIn) |
| double[][] inTable; // 1D input table ([channel][table]) |
| short[][] outTable; // 1D input table ([channel][table]) |
| double[] clut; // The color lookup table |
| float[][] inMatrix; // input matrix (XYZ only) |
| boolean useMatrix; // Whether to use the matrix or not. |
| int[] multiplier; |
| int[] offsets; // Hypercube offsets |
| boolean inputLab; // Set if the CLUT input CS is Lab |
| boolean outputLab; // Set if the CLUT output CS is Lab |
| |
| /** |
| * Constructor |
| * Requires a profile file to get the CLUT from and the tag of the |
| * CLUT to create. (icSigXToYZTag where X,Y = [A | B], Z = [0,1,2]) |
| */ |
| public ColorLookUpTable(ICC_Profile profile, int tag) |
| { |
| useMatrix = false; |
| |
| switch (tag) |
| { |
| case ICC_Profile.icSigAToB0Tag: |
| case ICC_Profile.icSigAToB1Tag: |
| case ICC_Profile.icSigAToB2Tag: |
| if (profile.getColorSpaceType() == ColorSpace.TYPE_XYZ) |
| useMatrix = true; |
| inputLab = false; |
| outputLab = (profile.getPCSType() == ColorSpace.TYPE_Lab); |
| break; |
| case ICC_Profile.icSigBToA0Tag: |
| case ICC_Profile.icSigBToA1Tag: |
| case ICC_Profile.icSigBToA2Tag: |
| if (profile.getPCSType() == ColorSpace.TYPE_XYZ) |
| useMatrix = true; |
| inputLab = (profile.getPCSType() == ColorSpace.TYPE_Lab); |
| outputLab = false; |
| break; |
| default: |
| throw new IllegalArgumentException("Not a clut-type tag."); |
| } |
| |
| byte[] data = profile.getData(tag); |
| if (data == null) |
| throw new IllegalArgumentException("Unsuitable profile, does not contain a CLUT."); |
| |
| // check 'mft' |
| if (data[0] != 0x6d || data[1] != 0x66 || data[2] != 0x74) |
| throw new IllegalArgumentException("Unsuitable profile, invalid CLUT data."); |
| |
| if (data[3] == 0x32) |
| readClut16(data); |
| else if (data[3] == 0x31) |
| readClut8(data); |
| else |
| throw new IllegalArgumentException("Unknown/invalid CLUT type."); |
| } |
| |
| /** |
| * Loads a 16-bit CLUT into our data structures |
| */ |
| private void readClut16(byte[] data) |
| { |
| ByteBuffer buf = ByteBuffer.wrap(data); |
| |
| nIn = data[8] & (0xFF); |
| nOut = data[9] & (0xFF); |
| nInTableEntries = buf.getShort(48); |
| nOutTableEntries = buf.getShort(50); |
| gridpoints = data[10] & (0xFF); |
| |
| inMatrix = new float[3][3]; |
| for (int i = 0; i < 3; i++) |
| for (int j = 0; j < 3; j++) |
| inMatrix[i][j] = ((float) (buf.getInt(12 + (i * 3 + j) * 4))) / 65536.0f; |
| |
| inTable = new double[nIn][nInTableEntries]; |
| for (int channel = 0; channel < nIn; channel++) |
| for (int i = 0; i < nInTableEntries; i++) |
| inTable[channel][i] = (double) ((int) buf.getShort(52 |
| + (channel * nInTableEntries |
| + i) * 2) |
| & (0xFFFF)) / 65536.0; |
| |
| nClut = nOut; |
| multiplier = new int[nIn]; |
| multiplier[nIn - 1] = nOut; |
| for (int i = 0; i < nIn; i++) |
| { |
| nClut *= gridpoints; |
| if (i > 0) |
| multiplier[nIn - i - 1] = multiplier[nIn - i] * gridpoints; |
| } |
| |
| int clutOffset = 52 + nIn * nInTableEntries * 2; |
| clut = new double[nClut]; |
| for (int i = 0; i < nClut; i++) |
| clut[i] = (double) ((int) buf.getShort(clutOffset + i * 2) & (0xFFFF)) / 65536.0; |
| |
| outTable = new short[nOut][nOutTableEntries]; |
| for (int channel = 0; channel < nOut; channel++) |
| for (int i = 0; i < nOutTableEntries; i++) |
| outTable[channel][i] = buf.getShort(clutOffset |
| + (nClut |
| + channel * nOutTableEntries + i) * 2); |
| |
| // calculate the hypercube corner offsets |
| offsets = new int[(1 << nIn)]; |
| offsets[0] = 0; |
| for (int j = 0; j < nIn; j++) |
| { |
| int factor = 1 << j; |
| for (int i = 0; i < factor; i++) |
| offsets[factor + i] = offsets[i] + multiplier[j]; |
| } |
| } |
| |
| /** |
| * Loads a 8-bit CLUT into our data structures. |
| */ |
| private void readClut8(byte[] data) |
| { |
| ByteBuffer buf = ByteBuffer.wrap(data); |
| |
| nIn = (data[8] & (0xFF)); |
| nOut = (data[9] & (0xFF)); |
| nInTableEntries = 256; // always 256 |
| nOutTableEntries = 256; // always 256 |
| gridpoints = (data[10] & (0xFF)); |
| |
| inMatrix = new float[3][3]; |
| for (int i = 0; i < 3; i++) |
| for (int j = 0; j < 3; j++) |
| inMatrix[i][j] = ((float) (buf.getInt(12 + (i * 3 + j) * 4))) / 65536.0f; |
| |
| inTable = new double[nIn][nInTableEntries]; |
| for (int channel = 0; channel < nIn; channel++) |
| for (int i = 0; i < nInTableEntries; i++) |
| inTable[channel][i] = (double) ((int) buf.get(48 |
| + (channel * nInTableEntries |
| + i)) & (0xFF)) / 255.0; |
| |
| nClut = nOut; |
| multiplier = new int[nIn]; |
| multiplier[nIn - 1] = nOut; |
| for (int i = 0; i < nIn; i++) |
| { |
| nClut *= gridpoints; |
| if (i > 0) |
| multiplier[nIn - i - 1] = multiplier[nIn - i] * gridpoints; |
| } |
| |
| int clutOffset = 48 + nIn * nInTableEntries; |
| clut = new double[nClut]; |
| for (int i = 0; i < nClut; i++) |
| clut[i] = (double) ((int) buf.get(clutOffset + i) & (0xFF)) / 255.0; |
| |
| outTable = new short[nOut][nOutTableEntries]; |
| for (int channel = 0; channel < nOut; channel++) |
| for (int i = 0; i < nOutTableEntries; i++) |
| outTable[channel][i] = (short) (buf.get(clutOffset + nClut |
| + channel * nOutTableEntries |
| + i) * 257); |
| |
| // calculate the hypercube corner offsets |
| offsets = new int[(1 << nIn)]; |
| offsets[0] = 0; |
| for (int j = 0; j < nIn; j++) |
| { |
| int factor = 1 << j; |
| for (int i = 0; i < factor; i++) |
| offsets[factor + i] = offsets[i] + multiplier[j]; |
| } |
| } |
| |
| /** |
| * Performs a lookup through the Color LookUp Table. |
| * If the CLUT tag type is AtoB the conversion will be from the device |
| * color space to the PCS, BtoA type goes in the opposite direction. |
| * |
| * For convenience, the PCS values for input or output will always be |
| * CIE XYZ (D50), if the actual PCS is Lab, the values will be converted. |
| * |
| * N-dimensional linear interpolation is used. |
| */ |
| float[] lookup(float[] in) |
| { |
| float[] in2 = new float[in.length]; |
| if (useMatrix) |
| { |
| for (int i = 0; i < 3; i++) |
| in2[i] = in[0] * inMatrix[i][0] + in[1] * inMatrix[i][1] |
| + in[2] * inMatrix[i][2]; |
| } |
| else if (inputLab) |
| in2 = XYZtoLab(in); |
| else |
| System.arraycopy(in, 0, in2, 0, in.length); |
| |
| // input table |
| for (int i = 0; i < nIn; i++) |
| { |
| int index = (int) Math.floor(in2[i] * (double) (nInTableEntries - 1)); // floor in |
| |
| // clip values. |
| if (index >= nInTableEntries - 1) |
| in2[i] = (float) inTable[i][nInTableEntries - 1]; |
| else if (index < 0) |
| in2[i] = (float) inTable[i][0]; |
| else |
| { |
| // linear interpolation |
| double alpha = in2[i] * ((double) nInTableEntries - 1.0) - index; |
| in2[i] = (float) (inTable[i][index] * (1 - alpha) |
| + inTable[i][index + 1] * alpha); |
| } |
| } |
| |
| // CLUT lookup |
| double[] output2 = new double[nOut]; |
| double[] weights = new double[(1 << nIn)]; |
| double[] clutalpha = new double[nIn]; // interpolation values |
| int offset = 0; // = gp |
| for (int i = 0; i < nIn; i++) |
| { |
| int index = (int) Math.floor(in2[i] * ((double) gridpoints - 1.0)); |
| double alpha = in2[i] * ((double) gridpoints - 1.0) - (double) index; |
| |
| // clip values. |
| if (index >= gridpoints - 1) |
| { |
| index = gridpoints - 1; |
| alpha = 1.0; |
| } |
| else if (index < 0) |
| index = 0; |
| clutalpha[i] = alpha; |
| offset += index * multiplier[i]; |
| } |
| |
| // Calculate interpolation weights |
| weights[0] = 1.0; |
| for (int j = 0; j < nIn; j++) |
| { |
| int factor = 1 << j; |
| for (int i = 0; i < factor; i++) |
| { |
| weights[factor + i] = weights[i] * clutalpha[j]; |
| weights[i] *= (1.0 - clutalpha[j]); |
| } |
| } |
| |
| for (int i = 0; i < nOut; i++) |
| output2[i] = weights[0] * clut[offset + i]; |
| |
| for (int i = 1; i < (1 << nIn); i++) |
| { |
| int offset2 = offset + offsets[i]; |
| for (int f = 0; f < nOut; f++) |
| output2[f] += weights[i] * clut[offset2 + f]; |
| } |
| |
| // output table |
| float[] output = new float[nOut]; |
| for (int i = 0; i < nOut; i++) |
| { |
| int index = (int) Math.floor(output2[i] * ((double) nOutTableEntries |
| - 1.0)); |
| |
| // clip values. |
| if (index >= nOutTableEntries - 1) |
| output[i] = outTable[i][nOutTableEntries - 1]; |
| else if (index < 0) |
| output[i] = outTable[i][0]; |
| else |
| { |
| // linear interpolation |
| double a = output2[i] * ((double) nOutTableEntries - 1.0) |
| - (double) index; |
| output[i] = (float) ((double) ((int) outTable[i][index] & (0xFFFF)) * (1 |
| - a) |
| + (double) ((int) outTable[i][index + 1] & (0xFFFF)) * a) / 65536f; |
| } |
| } |
| |
| if (outputLab) |
| return LabtoXYZ(output); |
| return output; |
| } |
| |
| /** |
| * Converts CIE Lab coordinates to (D50) XYZ ones. |
| */ |
| private float[] LabtoXYZ(float[] in) |
| { |
| // Convert from byte-packed format to a |
| // more convenient one (actual Lab values) |
| // (See ICC spec for details) |
| // factor is 100 * 65536 / 65280 |
| in[0] = (float) (100.392156862745 * in[0]); |
| in[1] = (in[1] * 256.0f) - 128.0f; |
| in[2] = (in[2] * 256.0f) - 128.0f; |
| |
| float[] out = new float[3]; |
| |
| out[1] = (in[0] + 16.0f) / 116.0f; |
| out[0] = in[1] / 500.0f + out[1]; |
| out[2] = out[1] - in[2] / 200.0f; |
| |
| for (int i = 0; i < 3; i++) |
| { |
| double exp = out[i] * out[i] * out[i]; |
| if (exp <= 0.008856) |
| out[i] = (out[i] - 16.0f / 116.0f) / 7.787f; |
| else |
| out[i] = (float) exp; |
| out[i] = D50[i] * out[i]; |
| } |
| return out; |
| } |
| |
| /** |
| * Converts CIE XYZ coordinates to Lab ones. |
| */ |
| private float[] XYZtoLab(float[] in) |
| { |
| float[] temp = new float[3]; |
| |
| for (int i = 0; i < 3; i++) |
| { |
| temp[i] = in[i] / D50[i]; |
| |
| if (temp[i] <= 0.008856f) |
| temp[i] = (7.7870689f * temp[i]) + (16f / 116.0f); |
| else |
| temp[i] = (float) Math.exp((1.0 / 3.0) * Math.log(temp[i])); |
| } |
| |
| float[] out = new float[3]; |
| out[0] = (116.0f * temp[1]) - 16f; |
| out[1] = 500.0f * (temp[0] - temp[1]); |
| out[2] = 200.0f * (temp[1] - temp[2]); |
| |
| // Normalize to packed format |
| out[0] = (float) (out[0] / 100.392156862745); |
| out[1] = (out[1] + 128f) / 256f; |
| out[2] = (out[2] + 128f) / 256f; |
| for (int i = 0; i < 3; i++) |
| { |
| if (out[i] < 0f) |
| out[i] = 0f; |
| if (out[i] > 1f) |
| out[i] = 1f; |
| } |
| return out; |
| } |
| } |