java 图像灰度化与二值化.docx

java 图像灰度化与二值化 1: package org.chinasb.client; 2: 3: import java.awt.Color; 4: import java.awt.image.BufferedImage; 5: import java.io.File; 6: import java.io.IOException; 7: 8: import javax.imageio.ImageIO; 9: 10: public class BinaryTest 11: 12: public static void main(String args) throws IOException 13: BufferedImage bufferedImage = ImageIO.read(new File(D:/passCodeAction.jpg); 14: int h = bufferedImage.getHeight(); 15: int w = bufferedImage.getWidth(); 16: 17: / 灰度化 18: int gray = new intwh; 19: for (int x = 0; x w; x+) 20: for (int y = 0; y 16) & 0xFF; 23: int g = (argb 8) & 0xFF; 24: int b = (argb 0) & 0xFF; 25: int grayPixel = (int) (b * 29 + g * 150 + r * 77 + 128) 8); 26: grayxy = grayPixel; 27: 28: 29: 30: / 二值化 31: int threshold = ostu(gray, w, h); 32: BufferedImage binaryBufferedImage = new BufferedImage(w, h, BufferedImage.TYPE_BYTE_BINARY); 33: for (int x = 0; x w; x+) 34: for (int y = 0; y threshold) 36: grayxy |= 0x00FFFF; 37: else 38: grayxy &= 0xFF0000; 39: 40: binaryBufferedImage.setRGB(x, y, grayxy); 41: 42: 43: 44: / 矩阵打印 45: for (int y = 0; y h; y+) 46: for (int x = 0; x w; x+) 47: if (isBlack(binaryBufferedImage.getRGB(x, y) 48: System.out.print(*); 49: else 50: System.out.print( ); 51: 52: 53: System.out.println(); 54: 55: 56: ImageIO.write(binaryBufferedImage, jpg, new File(D:/code.jpg); 57: 58: 59: public static boolean isBlack(int colorInt) 60: Color color = new Color(colorInt); 61: if (color.getRed() + color.getGreen() + color.getBlue() 300) 70: return true; 71: 72: return false; 73: 74: 75: public static int isBlackOrWhite(int colorInt) 76: if (getColorBright(colorInt) 730) 77: return 1; 78: 79: return 0; 80: 81: 82: public static int getColorBright(int colorInt) 83: Color color = new Color(colorInt); 84: return color.getRed() + color.getGreen() + color.getBlue(); 85: 86: 87: public static int ostu(int gray, int w, int h) 88: int histData = new intw * h; 89: / Calculate histogram 90: for (int x = 0; x w; x+) 91: for (int y = 0; y h; y+) 92: int red = 0xFF & grayxy; 93: histDatared+; 94: 95: 96: 97: / Total number of pixels 98: int total = w * h; 99: 100: float sum = 0; 101: for (int t = 0; t 256; t+) 102: sum += t * histDatat; 103: 104: float sumB = 0; 105: int wB = 0; 106: int wF = 0; 107: 108: float varMax = 0; 109: int threshold = 0; 110: 111: f