MpPreview/app/src/main/java/com/xypower/mppreview/RawToJpgConverter.java

package com.xypower.mppreview;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

public class RawToJpgConverter {


    public static List<String> listFiles(File directory) {
        ArrayList list = new ArrayList();
        File[] files = directory.listFiles();
        if (files != null) {
            for (File file : files) {
                if (file.isDirectory()) {
                    listFiles(file); // 递归遍历子目录
                } else {
                    // 这里可以处理文件，例如打印文件名
                    list.add(file.getName());
                }
            }
        }
        return list;
    }

    public static void convertDngToPng(String dngFile, String pngFile) {
        ImageDecoder.Source src = ImageDecoder.createSource(new File(dngFile));
        Bitmap bmp = null;
        FileOutputStream output = null;

        try {
            bmp = ImageDecoder.decodeBitmap(src);
            output = new FileOutputStream(new File(pngFile));
            bmp.compress(Bitmap.CompressFormat.PNG, 100, output);
        } catch (Exception ex) {
            ex.printStackTrace();
        } finally {
            closeOutput(output);
            if (bmp != null) {
                bmp.recycle();
            }
        }
    }


    public static Bitmap convertRawToJpg(String path, String outpath) throws IOException {
        // 1. 读取raw资源到字节数组
        InputStream inputStream = new FileInputStream(path);
        byte[] rawData = inputStreamToByteArray(inputStream);

        // 2. 将字节数组解码为Bitmap
        Bitmap rawBitmap = BitmapFactory.decodeByteArray(rawData, 0, rawData.length);

        // 3. 如果需要，可以在这里对Bitmap进行处理

        // 4. 创建一个新的字节数组输出流，用于存储JPG格式的图像数据
        FileOutputStream outputStream = new FileOutputStream(outpath);
        ByteArrayOutputStream bytestream = new ByteArrayOutputStream();

        // 5. 将Bitmap以JPG格式编码到输出流中
        rawBitmap.compress(Bitmap.CompressFormat.JPEG, 100, bytestream);

        // 6. 将输出流转换为字节数组，并关闭输出流
        byte[] jpgData = bytestream.toByteArray();
        outputStream.write(jpgData);
        outputStream.close();

        // 7. 返回JPG格式的Bitmap
        return BitmapFactory.decodeByteArray(jpgData, 0, jpgData.length);
    }

    private static byte[] inputStreamToByteArray(InputStream inputStream) throws IOException {
        byte[] buffer = new byte[1024];
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        int len;
        while ((len = inputStream.read(buffer)) != -1) {
            byteArrayOutputStream.write(buffer, 0, len);
        }
        byte[] data = byteArrayOutputStream.toByteArray();
        byteArrayOutputStream.close();
        inputStream.close();
        return data;
    }
}