java 圖片切割,縮放,轉換類型等等

原創

2020-02-21 14:46

import java.io.*;
import java.awt.*;
import java.awt.image.*;
import java.awt.Graphics;
import java.awt.color.ColorSpace;
import javax.imageio.ImageIO;
public class ImageCut {
/**
* 縮放圖像
*
* @param srcImageFile
*            源圖像文件地址
* @param result
*            縮放後的圖像地址
* @param scale
*            縮放比例
* @param flag
*            縮放選擇:true 放大; false 縮小;
*/
public static void scale(String srcImageFile, String result, int scale,
   boolean flag) {
try {
   BufferedImage src = ImageIO.read(new File(srcImageFile)); // 讀入文件
   int width = src.getWidth(); // 得到源圖寬
   int height = src.getHeight(); // 得到源圖長
   if (flag) {
    // 放大
    width = width * scale;
    height = height * scale;
   } else {
    // 縮小
    width = width / scale;
    height = height / scale;
   }
   Image image = src.getScaledInstance(width, height,
     Image.SCALE_DEFAULT);
   BufferedImage tag = new BufferedImage(width, height,
     BufferedImage.TYPE_INT_RGB);
   Graphics g = tag.getGraphics();
   g.drawImage(image, 0, 0, null); // 繪製縮小後的圖
   g.dispose();
   ImageIO.write(tag, "JPEG", new File(result));// 輸出到文件流
} catch (IOException e) {
   e.printStackTrace();
}
}
/**
* 圖像切割
*
* @param srcImageFile
*            源圖像地址
* @param descDir
*            切片目標文件夾
* @param destWidth
*            目標切片寬度
* @param destHeight
*            目標切片高度
*/
public static void cut(String srcImageFile, String descDir, int destWidth,
   int destHeight) {
try {
   Image img;
   ImageFilter cropFilter;
   // 讀取源圖像
   BufferedImage bi = ImageIO.read(new File(srcImageFile));
   int srcWidth = bi.getHeight(); // 源圖寬度
   int srcHeight = bi.getWidth(); // 源圖高度
   if (srcWidth > destWidth && srcHeight > destHeight) {
    Image image = bi.getScaledInstance(srcWidth, srcHeight,
      Image.SCALE_DEFAULT);
    destWidth = 200; // 切片寬度
    destHeight = 150; // 切片高度
    int cols = 0; // 切片橫向數量
    int rows = 0; // 切片縱向數量
    // 計算切片的橫向和縱向數量
    if (srcWidth % destWidth == 0) {
     cols = srcWidth / destWidth;
    } else {
     cols = (int) Math.floor(srcWidth / destWidth) + 1;
    }
    if (srcHeight % destHeight == 0) {
     rows = srcHeight / destHeight;
    } else {
     rows = (int) Math.floor(srcHeight / destHeight) + 1;
    }
    // 循環建立切片
    // 改進的想法:是否可用多線程加快切割速度
    for (int i = 0; i < rows; i++) {
     for (int j = 0; j < cols; j++) {
      // 四個參數分別爲圖像起點座標和寬高
      // 即: CropImageFilter(int x,int y,int width,int height)
      cropFilter = new CropImageFilter(j * 200, i * 150,
        destWidth, destHeight);
      img = Toolkit.getDefaultToolkit().createImage(
        new FilteredImageSource(image.getSource(),
          cropFilter));
      BufferedImage tag = new BufferedImage(destWidth,
        destHeight, BufferedImage.TYPE_INT_RGB);
      Graphics g = tag.getGraphics();
      g.drawImage(img, 0, 0, null); // 繪製縮小後的圖
      g.dispose();
      // 輸出爲文件
      ImageIO.write(tag, "JPEG", new File(descDir
        + "pre_map_" + i + "_" + j + ".jpg"));
     }
    }
   }
} catch (Exception e) {
   e.printStackTrace();
}
}
/**
* 圖像類型轉換
     * GIF->JPG GIF->PNG PNG->JPG PNG->GIF(X)
     */
public static void convert(String source, String result) {
try {
   File f = new File(source);
   f.canRead();
   f.canWrite();
   BufferedImage src = ImageIO.read(f);
   ImageIO.write(src, "JPG", new File(result));
} catch (Exception e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
}
}
/**
* 彩色轉爲黑白
*
* @param source
* @param result
*/
public static void gray(String source, String result) {
try {
   BufferedImage src = ImageIO.read(new File(source));
   ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
   ColorConvertOp op = new ColorConvertOp(cs, null);
   src = op.filter(src, null);
   ImageIO.write(src, "JPEG", new File(result));
} catch (IOException e) {
   e.printStackTrace();
}
}
/**
* @param args
*/
public static void main(String[] args) {
//cut("e:/1.jpg", "e:/t/", 200, 150);
}
}