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1 import java.awt.*;
2 import java.awt.image.*;
3 import java.awt.event.*;
4 import java.applet.*;
5 import java.io.*;
6 import JSci.maths.wavelet.symmlet8.*;
7
8
15 public final class ImageTransform extends Applet {
16 final int W=256;
17 final FastSymmlet8 fwt=new FastSymmlet8();
18 final float[][] mY=new float[W][W];
19 final float[][] mI=new float[W][W];
20 final float[][] mQ=new float[W][W];
21 Image lena;
22 Image lenaTransformed;
23
24 public void init() {
25 System.err.println("(C) 1999 Daniel Lemire, Ph.D.");
26 setSize(2*W,W);
27 System.err.println("Loading image...");
28 MediaTracker mt=new MediaTracker(this);
29 Class  thisclass=this.getClass();
30 InputStream is=thisclass.getResourceAsStream("lena.gif");
31 if(is!=null)
32 System.err.println("Image found...");
33 else
34 System.err.println("Image cannot be found!");
35 int b;
36 ByteArrayOutputStream bais=new ByteArrayOutputStream();
37 try {
38 while((b=is.read())!=-1) {
39 bais.write(b);
40 }
41 } catch(IOException ioe) {
42 ioe.printStackTrace();
43 }
44 System.err.println("Image read...");
45 lena=Toolkit.getDefaultToolkit().createImage(bais.toByteArray());
46 mt.addImage(lena,0,W,W);
47 try {
48 mt.waitForAll();
49 } catch (InterruptedException ie) {
50 ie.printStackTrace();
51 }
52 System.err.println("Image loaded...");
53 int[] pixels = new int[W * W];
54 PixelGrabber pg = new PixelGrabber(lena, 0, 0, W, W, pixels, 0, W);
55 try {
56 pg.grabPixels();
57 } catch (InterruptedException ie) {
58 ie.printStackTrace();
59 }
60 byte red,green,blue;
61 for(int k=0;k<W;k++) {
62 for(int l=0;l<W;l++) {
63 red = (byte)( ((pixels[k*W+l]>>16) & 0xFF) -128);
64 green = (byte)( ((pixels[k*W+l]>>8) & 0xFF) - 128);
65 blue = (byte)( (pixels[k*W+l] & 0xFF) - 128);
66 mY[k][l] = ( red*.299f+green*.587f+blue*.114f);
67 }
68 }
69 transform();
70 quantize();
71 final int two24 = twoPower(24);
72 final int two16 = twoPower(16);
73 final int two8 = twoPower(8);
74 for(int k=0;k<W;k++) {
75 for(int l=0;l<W;l++) {
76 pixels[k*W+l]=(int)mY[k][l]*two16 +(int)mY[k][l]*two8 + (int)mY[k][l] -two24;
77 }
78 }
79 MemoryImageSource topmis=new MemoryImageSource(W, W, pixels, 0, W);
80 lenaTransformed=createImage(topmis);
81 mt.addImage(lenaTransformed,1,W,W);
82 try {
83 mt.waitForAll();
84 } catch (InterruptedException ie) {
85 ie.printStackTrace();
86 }
87 this.setFont(new Font("Default",Font.BOLD,12));
88 }
89
90 private static int twoPower(int exp)
91 {
92 int result = 1;
93 for(int k = 0; k < exp; ++k)
94 result = 2*result;
95 return result;
96 }
97
98 public String getAppletInfo() {
99 return "This applet is meant to illustrate the FWT classes in JSci";
100 }
101
102 private void transform() {
103 transformColumns();
104 transformRows();
105 }
106 private void transformColumns() {
107 float[] ColumnVector=new float[W];
108 for(int col = 0; col <W; ++col) {
109 for(int row = 0; row < W; ++row)
110 ColumnVector[row] = mY[row][col];
111 fwt.transform(ColumnVector);
112 for(int row = 0; row < W; ++row)
113 mY[row][col] = ColumnVector[row];
114 }
115 }
116 private void transformRows() {
117 for(int row = 0; row < W; ++row) {
118 fwt.transform(mY[row]);
119 }
120 }
121
122 private void quantize() {
123 float max=mY[0][0];
124 float min=mY[0][0];
125 for(int k=0;k<W;k++) {
126 for(int l=0;l<W;l++) {
127 max=Math.max(mY[k][l],max);
128 min=Math.min(mY[k][l],min);
129 }
130 }
131 for(int k=0;k<W;k++) {
132 for(int l=0;l<W;l++) {
133 mY[k][l]=Math.round((mY[k][l]-min)/(max-min)*255.0);
134 }
135 }
136 }
137
138 public void paint(Graphics g) {
139 FontMetrics fm=this.getFontMetrics(this.getFont());
140 int fontheight=fm.getHeight();
141 g.setColor(Color.white);
142 g.drawImage(lena,0,0,this);
143 g.drawImage(lenaTransformed,256,0,this);
144 g.drawString("Real time computation of the Fast Wavelet Transform in Java",10,W-4*fontheight);
145 g.drawString("using "+(int)(Math.log(W)/Math.log(2)-3)+" iterations and Symmlet8 wavelets.",10,W-3*fontheight);
146 g.drawString ("(Only the Y channel is shown.)",10,W-2*fontheight);
147 g.drawString("Notice how economical the FWT representation is!",10,W-fontheight);
148 }
149 }
150
151
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