1    /* 
2     * Created by DocJava, Inc. 
3     * User: lyon 
4     * Date: Feb 28, 2003 
5     * Time: 7:44:33 AM 
6     */ 
7    package j2d.hpp; 
8     
9    import math.RgbStats; 
10    
11   import java.awt.*; 
12    
13    
14   public class EnaheFilter 
15           implements HppFilterInterface { 
16       /* 
17            short lut[] = tt.getLut(); 
18           RgbStats rgbStats = new RgbStats(ib.getImage()); 
19           double averageCmf[] = rgbStats.getAverageCmf(); 
20           for (short i = 0; i < lut.length; i++) 
21               lut[i] = (short) (255 * averageCmf[i]); 
22           applyLut(lut); 
23       */ 
24       double averageCmf[] = null; 
25       double alpha; 
26    
27       public EnaheFilter(Image img, double alpha) { 
28           this.alpha = alpha; 
29           RgbStats rgbStats = new RgbStats(img); 
30           this.averageCmf = rgbStats.getAverageCmf(); 
31       } 
32    
33       public short getR(int r) { 
34           return 
35                   getEnauhe(r); 
36       } 
37    
38       private short getEnauhe(int r) { 
39           short v = (short) 
40                   (255 * (-Math.log(1.0 - averageCmf[r]) / alpha)); 
41           if (v < 0) return v; 
42           if (v > 255) return 255; 
43           return v; 
44       } 
45    
46       public short getG(int g) { 
47           return getR(g); 
48       } 
49    
50       public short getB(int b) { 
51           return getR(b); 
52       } 
53    
54   } 
55