package cc.mrbird.febs.mall.test;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

public class PixelateImage {

    public static void main(String[] args) {
        handleDpi(new File("D:\\image\\inputDpi.png"),50,50);
        getPixel("D:\\image\\input.png");
        try {
            resizeImage("D:\\image\\input.png","D:\\image\\output.png",360);//将图片压缩至100宽
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * 功能：获取图片像素
     * * @param filePath 图片路径
     */
    public static void getPixel(String filePath){
        File file = new File(filePath);
        BufferedImage bi = null;
        try {
            bi = ImageIO.read(file);
        } catch (Exception e) {
            e.printStackTrace();
        }
        int width = bi.getWidth(); // 像素
        int height = bi.getHeight(); // 像素
        System.out.println("width=" + width + ",height=" + height + ".");
    }


    /**
     * @param inputPath  源图片路径
     * @param outputPath  修改大小后图片路径
     * @param scaleSize 图片的修改比例，目标宽度
     */
    public static void resizeImage(String inputPath, String outputPath,int scaleSize) throws IOException {

        File srcFile = new File(inputPath);
        Image srcImg = ImageIO.read(srcFile);
        BufferedImage bi = null;
        try {
            bi = ImageIO.read(srcFile);
        } catch (Exception e) {
            e.printStackTrace();
        }
        float width = bi.getWidth(); // 像素
        float height = bi.getHeight(); // 像素
        float scale = width/scaleSize;
        BufferedImage buffImg = null;
        buffImg = new BufferedImage(scaleSize, (int)(height/scale), BufferedImage.TYPE_INT_RGB);
        //使用TYPE_INT_RGB修改的图片会变色
        buffImg.getGraphics().drawImage(
                srcImg.getScaledInstance(scaleSize, (int)(height/scale), Image.SCALE_SMOOTH), 0,
                0, null);

        ImageIO.write(buffImg, "JPEG", new File(outputPath));
    }

    /**
     * 改变图片DPI
     *
     * @param file
     * @param xDensity
     * @param yDensity
     */
    public static void handleDpi(File file, int xDensity, int yDensity) {
        try {
            BufferedImage image = ImageIO.read(file);
            JPEGImageEncoder jpegEncoder = JPEGCodec.createJPEGEncoder(new FileOutputStream(file));
            JPEGEncodeParam jpegEncodeParam = jpegEncoder.getDefaultJPEGEncodeParam(image);
            jpegEncodeParam.setDensityUnit(JPEGEncodeParam.DENSITY_UNIT_DOTS_INCH);
            jpegEncoder.setJPEGEncodeParam(jpegEncodeParam);
            jpegEncodeParam.setQuality(0.1f, false);
            jpegEncodeParam.setXDensity(xDensity);
            jpegEncodeParam.setYDensity(yDensity);
            jpegEncoder.encode(image, jpegEncodeParam);
            image.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}