图像的高斯金字塔用java编写的

1、一：图像金字塔基本操作对一张图像不断的模糊之后向下采样，得到不同分辨率的图像，同时每次得到的新的图像宽与高是原来图像的1/2, 最常见就是基于高斯的模糊之后采样，得到的一系列图像称为高斯金字塔。高斯金字塔不同(DoG)又称为拉普拉斯金字塔，其计算公式如下：L(i) = G(i) expand(G(i+1)第i层拉普拉斯金字塔是由第i层高斯金字塔减去第i+1层高斯金字塔expand之后得到。本文得到的DoG(Difference of Gaussian)结果如下：二：关键代码解析金字塔reduce操作实现代码如下：java view plaincopy1 private BufferedImag

2、e pyramidReduce(BufferedImage src) 2 int width = src.getWidth(); 3 int height = src.getHeight(); 4 BufferedImage dest = createSubCompatibleDestImage(src, null); 5 int inPixels = new intwidth*height; 6 int ow = width/2; 7 int oh = height/2; 8 int outPixels = new intow*oh; 9 getRGB(src, 0, 0, width, h

3、eight, inPixels ); 10 int inRow=0, inCol = 0, index = 0, oudex =0, ta = 0; 11 float keneralData = this.getHVGaussianKeneral(); 12 for(int row=0; row<oh; row+) 13 for(int col=0; col<ow; col+) 14 inRow = 2* row; 15 inCol = 2* col; 16 if(inRow >= height) 17 inRow = 0; 18 19 if(inCol >= widt

4、h) 20 inCol = 0; 21 22 float sumRed = 0, sumGreen = 0, sumBlue = 0; 23 for(int subRow = -2; subRow <= 2; subRow+) 24 int inRowOff = inRow + subRow; 25 if(inRowOff >= height | inRowOff < 0) 26 inRowOff = 0; 27 28 for(int subCol = -2; subCol <= 2; subCol+) 29 int inColOff = inCol + subCol;

5、 30 if(inColOff >= width | inColOff < 0) 31 inColOff = 0; 32 33 index = inRowOff * width + inColOff; 34 ta = (inPixelsindex >> 24) & 0xff; 35 int red = (inPixelsindex >> 16) & 0xff; 36 int green = (inPixelsindex >> 8) & 0xff; 37 int blue = inPixelsindex & 0xff

6、; 38 sumRed += keneralDatasubRow + 2subCol + 2 * red; 39 sumGreen += keneralDatasubRow + 2subCol + 2 * green; 40 sumBlue += keneralDatasubRow + 2subCol + 2 * blue; 41 42 43 44 oudex = row * ow + col; 45 outPixelsoudex = (ta << 24) | (clamp(sumRed) << 16) | (clamp(sumGreen) << 8) |

7、clamp(sumBlue); 46 47 48 setRGB( dest, 0, 0, ow, oh, outPixels ); 49 return dest; 50 金字塔expand实现代码如下：java view plaincopy51 public BufferedImage pyramidExpand(BufferedImage src) 52 int width = src.getWidth(); 53 int height = src.getHeight(); 54 int inPixels = new intwidth*height; 55 getRGB(src, 0, 0,

8、 width, height, inPixels ); 56 int ow = 2*width; 57 int oh =2*height; 58 int outPixels = new intow * oh; 59 int index = 0, outdex = 0, ta = 0; 60 float keneralData = this.getHVGaussianKeneral(); 61 BufferedImage dest = createTwiceCompatibleDestImage(src, null); 62 for(int row=0; row<oh; row+) 63

9、for(int col=0; col<ow; col+) 64 float sumRed = 0, sumGreen = 0, sumBlue = 0; 65 for(int subRow = -2; subRow <= 2; subRow+) 66 double srcRow = (row + subRow)/2.0; 67 double j = Math.floor(srcRow); 68 double t = srcRow - j; 69 if(t > 0) 70 continue; 71 72 if(srcRow >= height | srcRow <

10、0) 73 srcRow = 0; 74 75 for(int subCol = -2; subCol <= 2; subCol+) 76 double srcColOff = (col + subCol)/2.0; 77 j = Math.floor(srcColOff); 78 t = srcColOff - j; 79 if(t > 0) 80 continue; 81 82 if(srcColOff >= width | srcColOff < 0) 83 srcColOff = 0; 84 85 index = (int)(srcRow * width + s

11、rcColOff); 86 ta = (inPixelsindex >> 24) & 0xff; 87 int red = (inPixelsindex >> 16) & 0xff; 88 int green = (inPixelsindex >> 8) & 0xff; 89 int blue = inPixelsindex & 0xff; 90 sumRed += keneralDatasubRow + 2subCol + 2 * red; 91 sumGreen += keneralDatasubRow + 2subCol

12、 + 2 * green; 92 sumBlue += keneralDatasubRow + 2subCol + 2 * blue; 93 94 95 outdex = row * ow + col; 96 outPixelsoutdex = (ta << 24) | (clamp(4.0f * sumRed) << 16) | (clamp(4.0f * sumGreen) << 8) | clamp(4.0f * sumBlue); 97 / outPixelsoutdex = (ta << 24) | (clamp(sumRed) <

13、;< 16) | (clamp(sumGreen) << 8) | clamp(sumBlue); 98 99 100 setRGB( dest, 0, 0, ow, oh, outPixels ); 101 return dest; 102 图像金字塔的reduce与expand过程都是卷积采样实现。特别注意的是expand操作不是reduce的可逆操作。关于什么是卷积，高斯滤波请参见博客上的其它相关文章。高斯金字塔全部算法源代码如下：java view plaincopy103 package com.gloomyfish.image.pyramid; 104 105 i

14、mport java.awt.image.BufferedImage; 106 import java.awt.image.ColorModel; 107 108 public class PyramidAlgorithm extends GaussianFilter 109 private float a; 110 111 public PyramidAlgorithm() 112 a = 0.4f; 113 114 115 public void setParameter(float p) 116 this.a = p; 117 118 119 public BufferedImage p

15、yramidDown(BufferedImage src, int level) 120 BufferedImage imagePyramids = new BufferedImagelevel + 1; 121 imagePyramids0 = src; 122 for(int i=1; i<imagePyramids.length; i+) 123 imagePyramidsi = pyramidReduce(imagePyramidsi-1); 124 125 return imagePyramids; 126 127 128 public BufferedImage pyrami

16、dUp(BufferedImage srcImage) 129 BufferedImage imagePyramids = new BufferedImagesrcImage.length; 130 for(int i=0; i<srcImage.length; i+) 131 imagePyramidsi = pyramidExpand(srcImagei); 132 133 return imagePyramids; 134 135 136 /* 137 * l1 = g1 - expand(g2) 138 * l2 = g2 - expand(g3) 139 * l0 = g0 -

17、 expand(g1) 140 * param reduceImages 141 * param expandImages 142 * return 143 */ 144 public BufferedImage getLaplacianPyramid(BufferedImage reduceImages) 145 BufferedImage laplaciImages = new BufferedImagereduceImages.length -1; 146 for(int i=1; i<reduceImages.length; i+) 147 BufferedImage expan

18、dImage = pyramidExpand(reduceImagesi); 148 laplaciImagesi-1 = createCompatibleDestImage(expandImage, null); 149 int width = reduceImagesi-1.getWidth(); 150 int height = reduceImagesi-1.getHeight(); 151 152 int ewidth = expandImage.getWidth(); 153 width = (width > ewidth) ? ewidth : width; 154 hei

19、ght = (height > expandImage.getHeight() ? expandImage.getHeight():height; 155 System.out.println(" width = " + width + " expand width = " + ewidth); 156 157 int reducePixels = new intwidth*height; 158 int expandPixels = new intwidth*height; 159 int laPixels = new intwidth*heig

20、ht; 160 getRGB( reduceImagesi-1, 0, 0, width, height, reducePixels); 161 getRGB( expandImage, 0, 0, width, height, expandPixels ); 162 int index = 0; 163 int er = 0, eg = 0, eb = 0; 164 for(int row=0; row<height; row+) 165 int ta = 0, tr = 0, tg = 0, tb = 0; 166 for(int col=0; col<width; col+)

21、 167 index = row * width + col; 168 ta = (reducePixelsindex >> 24) & 0xff; 169 tr = (reducePixelsindex >> 16) & 0xff; 170 tg = (reducePixelsindex >> 8) & 0xff; 171 tb = reducePixelsindex & 0xff; 172 173 ta = (expandPixelsindex >> 24) & 0xff; 174 er = (expa

22、ndPixelsindex >> 16) & 0xff; 175 eg = (expandPixelsindex >> 8) & 0xff; 176 eb = expandPixelsindex & 0xff; 177 178 tr = tr - er; 179 tg = tg - eg; 180 tb = tb - eb; 181 182 laPixelsindex = (ta << 24) | (clamp(tr) << 16) | (clamp(tg) << 8) | clamp(tb); 183 184

23、 185 setRGB( laplaciImagesi-1, 0, 0, width, height, laPixels ); 186 187 188 return laplaciImages; 189 190 191 private BufferedImage pyramidReduce(BufferedImage src) 192 int width = src.getWidth(); 193 int height = src.getHeight(); 194 BufferedImage dest = createSubCompatibleDestImage(src, null); 195

24、 int inPixels = new intwidth*height; 196 int ow = width/2; 197 int oh = height/2; 198 int outPixels = new intow*oh; 199 getRGB(src, 0, 0, width, height, inPixels ); 200 int inRow=0, inCol = 0, index = 0, oudex =0, ta = 0; 201 float keneralData = this.getHVGaussianKeneral(); 202 for(int row=0; row<

25、;oh; row+) 203 for(int col=0; col<ow; col+) 204 inRow = 2* row; 205 inCol = 2* col; 206 if(inRow >= height) 207 inRow = 0; 208 209 if(inCol >= width) 210 inCol = 0; 211 212 float sumRed = 0, sumGreen = 0, sumBlue = 0; 213 for(int subRow = -2; subRow <= 2; subRow+) 214 int inRowOff = inRo

26、w + subRow; 215 if(inRowOff >= height | inRowOff < 0) 216 inRowOff = 0; 217 218 for(int subCol = -2; subCol <= 2; subCol+) 219 int inColOff = inCol + subCol; 220 if(inColOff >= width | inColOff < 0) 221 inColOff = 0; 222 223 index = inRowOff * width + inColOff; 224 ta = (inPixelsindex

27、 >> 24) & 0xff; 225 int red = (inPixelsindex >> 16) & 0xff; 226 int green = (inPixelsindex >> 8) & 0xff; 227 int blue = inPixelsindex & 0xff; 228 sumRed += keneralDatasubRow + 2subCol + 2 * red; 229 sumGreen += keneralDatasubRow + 2subCol + 2 * green; 230 sumBlue +=

28、 keneralDatasubRow + 2subCol + 2 * blue; 231 232 233 234 oudex = row * ow + col; 235 outPixelsoudex = (ta << 24) | (clamp(sumRed) << 16) | (clamp(sumGreen) << 8) | clamp(sumBlue); 236 237 238 setRGB( dest, 0, 0, ow, oh, outPixels ); 239 return dest; 240 241 242 public BufferedImage

29、 createSubCompatibleDestImage(BufferedImage src, ColorModel dstCM) 243 if ( dstCM = null ) 244 dstCM = src.getColorModel(); 245 return new BufferedImage(dstCM, dstCM.createCompatibleWritableRaster(src.getWidth()/2, src.getHeight()/2), dstCM.isAlphaPremultiplied(), null); 246 247 248 public BufferedI

30、mage createTwiceCompatibleDestImage(BufferedImage src, ColorModel dstCM) 249 if ( dstCM = null ) 250 dstCM = src.getColorModel(); 251 return new BufferedImage(dstCM, dstCM.createCompatibleWritableRaster(src.getWidth()*2, src.getHeight()*2), dstCM.isAlphaPremultiplied(), null); 252 253 254 public Buf

31、feredImage pyramidExpand(BufferedImage src) 255 int width = src.getWidth(); 256 int height = src.getHeight(); 257 int inPixels = new intwidth*height; 258 getRGB(src, 0, 0, width, height, inPixels ); 259 int ow = 2*width; 260 int oh =2*height; 261 int outPixels = new intow * oh; 262 int index = 0, ou

32、tdex = 0, ta = 0; 263 float keneralData = this.getHVGaussianKeneral(); 264 BufferedImage dest = createTwiceCompatibleDestImage(src, null); 265 for(int row=0; row<oh; row+) 266 for(int col=0; col<ow; col+) 267 float sumRed = 0, sumGreen = 0, sumBlue = 0; 268 for(int subRow = -2; subRow <= 2;

33、 subRow+) 269 double srcRow = (row + subRow)/2.0; 270 double j = Math.floor(srcRow); 271 double t = srcRow - j; 272 if(t > 0) 273 continue; 274 275 if(srcRow >= height | srcRow < 0) 276 srcRow = 0; 277 278 for(int subCol = -2; subCol <= 2; subCol+) 279 double srcColOff = (col + subCol)/2

34、.0; 280 j = Math.floor(srcColOff); 281 t = srcColOff - j; 282 if(t > 0) 283 continue; 284 285 if(srcColOff >= width | srcColOff < 0) 286 srcColOff = 0; 287 288 index = (int)(srcRow * width + srcColOff); 289 ta = (inPixelsindex >> 24) & 0xff; 290 int red = (inPixelsindex >> 1

35、6) & 0xff; 291 int green = (inPixelsindex >> 8) & 0xff; 292 int blue = inPixelsindex & 0xff; 293 sumRed += keneralDatasubRow + 2subCol + 2 * red; 294 sumGreen += keneralDatasubRow + 2subCol + 2 * green; 295 sumBlue += keneralDatasubRow + 2subCol + 2 * blue; 296 297 298 outdex = row

36、 * ow + col; 299 outPixelsoutdex = (ta << 24) | (clamp(4.0f * sumRed) << 16) | (clamp(4.0f * sumGreen) << 8) | clamp(4.0f * sumBlue); 300 / outPixelsoutdex = (ta << 24) | (clamp(sumRed) << 16) | (clamp(sumGreen) << 8) | clamp(sumBlue); 301 302 303 setRGB( dest, 0,

37、 0, ow, oh, outPixels ); 304 return dest; 305 306 307 特别注意：我没有处理像素的宽与高，如果宽与高不是偶数可能会有问题，使用时请自己处理吧。UI实现源代码如下：java view plaincopy308 package com.gloomyfish.image.pyramid; 309 310 import java.awt.BorderLayout; 311 import java.awt.Dimension; 312 import java.awt.FlowLayout; 313 import java.awt.Graphics; 3

38、14 import java.awt.MediaTracker; 315 import java.awt.event.ActionEvent; 316 import java.awt.event.ActionListener; 317 import java.awt.image.BufferedImage; 318 import java.io.File; 319 import java.io.IOException; 320 321 import javax.imageio.ImageIO; 322 import javax.swing.JButton; 323 import javax.s

39、wing.JComponent; 324 import javax.swing.JFileChooser; 325 import javax.swing.JFrame; 326 import javax.swing.JPanel; 327 328 public class PyramidDemoUI extends JComponent implements ActionListener 329 330 /* 331 * 332 */ 333 private static final long serialVersionUID = 1L; 334 private JButton upButto

40、n; 335 private JButton downButton; 336 private BufferedImage reduceImages; 337 private BufferedImage expandImages; 338 private BufferedImage sourceImage; 339 private Dimension mySize; 340 private MediaTracker tracker; 341 342 public PyramidDemoUI(File f) 343 344 initComponents(f); 345 346 347 privat

41、e void initComponents(File f) 348 349 / TODO Auto-generated method stub 350 try 351 sourceImage = ImageIO.read(f); 352 catch (IOException e1) 353 e1.printStackTrace(); 354 355 356 tracker = new MediaTracker(this); 357 tracker.addImage(sourceImage, 1); 358 359 / blocked 10 seconds to load the image d

42、ata 360 try 361 if (!tracker.waitForID(1, 10000) 362 System.out.println("Load error."); 363 System.exit(1); 364 / end if 365 catch (InterruptedException e) 366 e.printStackTrace(); 367 System.exit(1); 368 / end catch 369 370 JPanel btnPanel = new JPanel(); 371 btnPanel.setLayout(new FlowLayout(FlowLayout.RIGHT); 372 upButton = new JButton("Laplacian Pyramid"); 373 downButton = new JButton("