Android图片压缩保存

JPEGHelper.java

import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
import com.iqiyi.qixiu.utils.Log;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;

public class JPEGHelper {

  private static final String TAG = "JPEGHelper";

  static {
    System.loadLibrary("cjpeg");
  }

  public JPEGHelper() {
  }

  public static Bitmap compressBySize(String srcPath, String dstPath, String imageName,
      int targetWidth, int targetHeight) {
    BitmapFactory.Options opts = new BitmapFactory.Options();
    opts.inJustDecodeBounds = true;// 不去真的解析图片，只是获取图片的头部信息，包含宽高等；
    Bitmap bitmap = BitmapFactory.decodeFile(srcPath, opts);
    // 得到图片的宽度、高度；
    int imgWidth = opts.outWidth;
    int imgHeight = opts.outHeight;
    // 分别计算图片宽度、高度与目标宽度、高度的比例；取大于等于该比例的最小整数；
    int widthRatio = (int) Math.ceil(imgWidth / (float) targetWidth);
    int heightRatio = (int) Math.ceil(imgHeight / (float) targetHeight);
    if (widthRatio > 1 || widthRatio > 1) {
      if (widthRatio > heightRatio) {
        opts.inSampleSize = widthRatio;
      } else {
        opts.inSampleSize = heightRatio;
      }
    }
    // 设置好缩放比例后，加载图片进内容；
    opts.inJustDecodeBounds = false;
    bitmap = BitmapFactory.decodeFile(srcPath, opts);

    if (!"".equals(dstPath)) {
      try {
        File f = new File(dstPath, imageName);
        f.createNewFile();

        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        bitmap.compress(CompressFormat.PNG, 0 /*ignored for PNG*/, bos);
        byte[] bitmapdata = bos.toByteArray();

        FileOutputStream fos = new FileOutputStream(f);
        fos.write(bitmapdata);
        fos.flush();
        fos.close();
      } catch (Exception e) {

      }
    }
    return bitmap;
  }

  public native int compress(String srcPath, String dstPath, int w, int h);

  public int compress(String srcPath, String dstPath, String imageName,int w, int h) {
    Log.d(TAG, "compress srcPath = " + srcPath);
    Log.d(TAG, "compress dstPath = " + dstPath);
    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(srcPath, options);
    Log.d(TAG, "compress source width = "
        + options.outWidth
        + " height = "
        + options.outHeight
        + " mineType = "
        + options.outMimeType);

    float scalex, scaley;
    scalex = (float) options.outWidth / w;
    scaley = (float) options.outHeight / h;

    int width = options.outWidth;
    int height = options.outHeight;

    if (scalex <= 1 && scaley <= 1) {
      width = options.outWidth;
      height = options.outHeight;
    } else if (scalex < scaley) {
      width = (int) (options.outWidth / scaley);
      height = (int) (options.outHeight / scaley);
    } else if (scalex >= scaley) {
      width = (int) (options.outWidth / scalex);
      height = (int) (options.outHeight / scalex);
    }
    Log.d(TAG, "compress dst width = " + width + " height = " + height);
    int retval = 1;

    try {
      File f = new File(dstPath, imageName);
      f.createNewFile();
    } catch (Exception e) {
      e.printStackTrace();
    }

    //if (isSupportedByCjpeg(options.outMimeType)) {
    //  Log.d(TAG, "The photo is supported by cjpeg");
    //  retval = compress(srcPath, dstPath + imageName, width, height);
    //} else {
      retval = saveAsJpegFile(srcPath, dstPath + imageName, width, height);
    //}
    Log.d(TAG, "retval = " + retval);
    return retval;
  }

  private boolean isSupportedByCjpeg(String minetype) {
    boolean result = false;
    if (minetype != null) {
      if (minetype.equalsIgnoreCase("image/jpeg")) {
        result = true;
      }
    }
    return result;
  }

  private int saveAsJpegFile(String srcPath, String dstPath, int w, int h) {
    int result = 0;

    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inPreferredConfig = Config.RGB_565;
    Bitmap origBmp = BitmapFactory.decodeFile(srcPath, options);
    if (origBmp == null) {
      Log.d(TAG, "Can't decode srcPath = " + srcPath);
      return 1;
    }

    try {
      origBmp.compress(CompressFormat.JPEG, 100, new FileOutputStream(dstPath));
      result = compress(srcPath, dstPath, w, h);
    } catch (FileNotFoundException e) {
      result = 1;
      e.printStackTrace();
    }

    origBmp.recycle();
    return result;
  }
}

libcjpeg.so

https://www.dropbox.com/s/9zl0zowcebr90eh/libcjpeg.so?dl=0