我的问题

我用我的安卓设备拍照。然后我从文件中解码该图片。

        Bitmap photo = BitmapFactory.decodeFile(EXTERNAL_IMAGE_PATH+File.separator+this._currentPhotoName+JPEG_FILE_SUFFIX);
        if (photo == null && data != null) 
            photo = (Bitmap) data.getExtras().get("data");
        else if (data == null && photo == null)
            Log.e("CCPhotoManager","Can't find image from file or from intent data.");

然后我检查那张图片，看看它是否需要旋转到正确的方向。

             try {
                ExifInterface exif = new ExifInterface(EXTERNAL_IMAGE_PATH+File.separator+this._currentPhotoName+JPEG_FILE_SUFFIX);
                int rotation = CCDataUtils.exifToDegrees(exif.getAttributeInt(ExifInterface.TAG_ORIENTATION,ExifInterface.ORIENTATION_NORMAL));
                Log.v("CCPhotoManager", "Rotation:"+rotation);
                if (rotation > 0) {
                    photo = this.convertSavedImageToCorrectOrientation(EXTERNAL_IMAGE_PATH+File.separator+this._currentPhotoName+JPEG_FILE_SUFFIX, photo, rotation);
                }
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }

如果确实需要旋转，我会调用此方法。

public Bitmap convertSavedImageToCorrectOrientation(String filePath,Bitmap photo,int rotation) {
        Log.d("CCPhotoManager", "Changing Orientation of photo located at: "+filePath+" Rotating by:"+rotation);
        int width = photo.getWidth();
        int height = photo.getHeight();


        Matrix matrix = new Matrix();
        matrix.preRotate(rotation);

        Bitmap adjusted = Bitmap.createBitmap(photo, 0, 0, width, height, matrix, true);

        try {
               FileOutputStream out = new FileOutputStream(filePath);
               adjusted.compress(Bitmap.CompressFormat.JPEG, 100, out);
        } catch (Exception e) {
               e.printStackTrace();
        }

        return adjusted;
    }

如果在 Bitmap adjusted = Bitmap.createBitmap(photo,0,0,width,高度，矩阵，真)；

只有 Samsung Galaxy S3 才会出现这种情况。它在 Samsung Galaxy Ace、HTC Hero 和 Sony Xperia U 上运行良好。

这里是错误。

10-17 14:33:33.950: E/AndroidRuntime(12556): java.lang.OutOfMemoryError
10-17 14:33:33.950: E/AndroidRuntime(12556):    at android.graphics.Bitmap.nativeCreate(Native Method)
10-17 14:33:33.950: E/AndroidRuntime(12556):    at android.graphics.Bitmap.createBitmap(Bitmap.java:605)
10-17 14:33:33.950: E/AndroidRuntime(12556):    at android.graphics.Bitmap.createBitmap(Bitmap.java:551)

内存也很大。

10-17 14:33:33.945: E/dalvikvm-heap(12556): Out of memory on a 31961104-byte allocation.

我认为这与周围的位图数量有关，但我不确定如何阻止此错误的发生。

我知道你可以对它们调用 .recycle(); 但它似乎不起作用。

我的问题

如何正确处理位图，以免出现 OOM 问题？

提前致谢

最佳答案

内存不足问题

//解码图像并缩放以减少内存消耗

private Bitmap decodeFile(File f){

try {
    //Decode image size
    BitmapFactory.Options o = new BitmapFactory.Options();
    o.inJustDecodeBounds = true;
    BitmapFactory.decodeStream(new FileInputStream(f),null,o);

    //The new size we want to scale to
    final int REQUIRED_SIZE=70;

    //Find the correct scale value. It should be the power of 2.
    int scale=1;
    while(o.outWidth/scale/2>=REQUIRED_SIZE && o.outHeight/scale/2>=REQUIRED_SIZE)
        scale*=2;

    //Decode with inSampleSize
    BitmapFactory.Options o2 = new BitmapFactory.Options();
    o2.inSampleSize=scale;
    return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
} catch (FileNotFoundException e) {}
return null;
}

关于android - 位图内存不足问题，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/12935793/