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import org.apache.xmlgraphics.image.codec.tiff.TIFFEncodeParam;
import org.apache.xmlgraphics.image.codec.util.ImageEncoder;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
public class ImageUtil {
public static void main(String[] args) throws IOException {
File testDataDir = new File("pic");
final String destDir = "picimages";
for (File file : testDataDir.listFiles()) {
cleanLinesInImage(file, destDir);
cleanLinesInImage(file, destDir);
cleanLinesInImage(file, destDir);
}
}
/**
* @param sfile 需要去噪的图像
* @param destDir 去噪后的图像保存地址
* @throws IOException
*/
public static void cleanLinesInImage(File sfile, String destDir) throws IOException {
File destF = new File(destDir);
if (!destF.exists()) {
destF.mkdirs();
}
BufferedImage bufferedImage = ImageIO.read(sfile);
int h = bufferedImage.getHeight();
int w = bufferedImage.getWidth();
// 灰度化
int[][] gray = new int[w][h];
for (int x = 0; x < w; x++) {
for (int y = 0; y < h; y++) {
int argb = bufferedImage.getRGB(x, y);
// 图像加亮（调整亮度识别率非常高）
int r = (int) (((argb >> 16) & 0xFF) * 1.1 + 30);
int g = (int) (((argb >> 8) & 0xFF) * 1.1 + 30);
int b = (int) (((argb >> 0) & 0xFF) * 1.1 + 30);
if (r >= 255) {
r = 255;
}
if (g >= 255) {
g = 255;
}
if (b >= 255) {
b = 255;
}
gray[x][y] = (int) Math
.pow((Math.pow(r, 2.2) * 0.2973 + Math.pow(g, 2.2)
* 0.6274 + Math.pow(b, 2.2) * 0.0753), 1 / 2.2);
}
}
// 二值化
int threshold = ostu(gray, w, h);
BufferedImage binaryBufferedImage = new BufferedImage(w, h, BufferedImage.TYPE_BYTE_BINARY);
for (int x = 0; x < w; x++) {
for (int y = 0; y < h; y++) {
if (gray[x][y] > threshold) {
gray[x][y] |= 0x00FFFF;
} else {
gray[x][y] &= 0xFF0000;
}
binaryBufferedImage.setRGB(x, y, gray[x][y]);
}
}
//去除干扰线条
// for(int y = 1; y < h-1; y++){
// for(int x = 1; x < w-1; x++){
// boolean flag = false ;
// if(isBlack(binaryBufferedImage.getRGB(x, y))){
// //左右均为空时，去掉此点
// if((binaryBufferedImage.getRGB(x-1, y)) && isWhite(binaryBufferedImage.getRGB(x+1, y))){
// flag = true;
// }
// //上下均为空时，去掉此点
// if(isWhite(binaryBufferedImage.getRGB(x, y+1)) && isWhite(binaryBufferedImage.getRGB(x, y-1))){
// flag = true;
// }
// //斜上下为空时，去掉此点
// if(isWhite(binaryBufferedImage.getRGB(x-1, y+1)) && isWhite(binaryBufferedImage.getRGB(x+1, y-1))){
// flag = true;
// }
// if(isWhite(binaryBufferedImage.getRGB(x+1, y+1)) && isWhite(binaryBufferedImage.getRGB(x-1, y-1))){
// flag = true;
// }
// if(flag){
// binaryBufferedImage.setRGB(x,y,-1);
// }
// }
// }
// }
//去除边框线
for (int y = 1; y < h; y++) {
for (int x = 1; x < w; x++) {
boolean flag = true;
int px = 15;
if (isBlack(binaryBufferedImage.getRGB(x, y))) {
if (x < w - px) {
for (int i = 1; i <= px; i++) {
//右15像素均为空时，去掉此行
if (isWhite(binaryBufferedImage.getRGB(x + i, y))) {
flag = false;
if (!flag) {
break;
}
}
}
}
for (int i = x; i < w; i++) {
if (flag) {
if (isBlack(binaryBufferedImage.getRGB(i, y))) {
binaryBufferedImage.setRGB(i, y, -1);
} else {
break;
}
}
}
flag = true;
if (y < h - px) {
for (int i = 1; i <= px; i++) {
//下15像素均为空时，去掉此列
if (isWhite(binaryBufferedImage.getRGB(x, y + i))) {
flag = false;
if (!flag) {
break;
}
}
}
}
for (int i = y; i <= h; i++) {
if (flag) {
if (isBlack(binaryBufferedImage.getRGB(x, i))) {
binaryBufferedImage.setRGB(x, i, -1);
} else {
break;
}
}
}
}
}
}
// 矩阵打印
for (int y = 0; y < h; y++) {
for (int x = 0; x < w; x++) {
if (isBlack(binaryBufferedImage.getRGB(x, y))) {
System.out.print("*");
} else {
System.out.print(" ");
}
}
System.out.println();
}
ImageIO.write(binaryBufferedImage, "tif", new File(destDir, sfile
.getName()));
}
public static boolean isBlack(int colorInt) {
Color color = new Color(colorInt);
if (color.getRed() + color.getGreen() + color.getBlue() <= 300) {
return true;
}
return false;
}
public static boolean isWhite(int colorInt) {
Color color = new Color(colorInt);
if (color.getRed() + color.getGreen() + color.getBlue() > 300) {
return true;
}
return false;
}
public static int isBlackOrWhite(int colorInt) {
if (getColorBright(colorInt) < 30 || getColorBright(colorInt) > 730) {
return 1;
}
return 0;
}
public static int getColorBright(int colorInt) {
Color color = new Color(colorInt);
return color.getRed() + color.getGreen() + color.getBlue();
}
public static int ostu(int[][] gray, int w, int h) {
int[] histData = new int[w * h];
// Calculate histogram
for (int x = 0; x < w; x++) {
for (int y = 0; y < h; y++) {
int red = 0xFF & gray[x][y];
histData[red]++;
}
}
// Total number of pixels
int total = w * h;
float sum = 0;
for (int t = 0; t < 256; t++) {
sum += t * histData[t];
}
float sumB = 0;
int wB = 0;
int wF = 0;
float varMax = 0;
int threshold = 0;
for (int t = 0; t < 256; t++) {
wB += histData[t]; // Weight Background
if (wB == 0) {
continue;
}
wF = total - wB; // Weight Foreground
if (wF == 0) {
break;
}
sumB += (float) (t * histData[t]);
float mB = sumB / wB; // Mean Background
float mF = (sum - sumB) / wF; // Mean Foreground
// Calculate Between Class Variance
float varBetween = (float) wB * (float) wF * (mB - mF) * (mB - mF);
// Check if new maximum found
if (varBetween > varMax) {
varMax = varBetween;
threshold = t;
}
}
return threshold;
}
}
