icc.lut.LookUpTable8Gamma Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of jj2000 Show documentation

Fork of jpeg2k code from https://code.google.com/p/jj2000/. This is a dependency for support of compression in Grib2 files in netCDF-java and TDS. We welcome bug fixes and other contributions to this code.

The newest version!

/*****************************************************************************
 *
 * $Id: LookUpTable8Gamma.java,v 1.1 2002/07/25 14:56:48 grosbois Exp $
 *
 * Copyright Eastman Kodak Company, 343 State Street, Rochester, NY 14650
 * $Date $
 *****************************************************************************/

package icc.lut;

import icc .tags.ICCCurveType;

/**
 * A Gamma based 16 bit lut.
 * 
 * @see		jj2000.j2k.icc.tags.ICCCurveType
 * @version	1.0
 * @author	Bruce A. Kern
 */
public class LookUpTable8Gamma extends LookUpTable8 {     
    
    /* Construct the lut 
     *   @param curve data 
     *   @param dwNumInput size of lut 
     *   @param dwMaxOutput max value of lut   
     */
    public LookUpTable8Gamma (
                 ICCCurveType curve,   // Pointer to the curve data            
                 int dwNumInput,       // Number of input values in created LUT
                 byte dwMaxOutput       // Maximum output value of the LUT
                 ) {
        super (curve, dwNumInput, dwMaxOutput);
        double dfE = ICCCurveType.CurveGammaToDouble(curve.entry(0)); // Gamma exponent for inverse transformation
        for (int i = 0; i < dwNumInput; i++)
            lut[i] = (byte) Math.floor(
                                       Math.pow((double)i / (dwNumInput - 1), dfE) * dwMaxOutput + 0.5
                                       ); }

    /* end class LookUpTable8Gamma */ }