Question

I have a big Memory Problem:

// in sourceImage is a big JPEG previously loaded
Matrix mat = new Matrix();
mat.postRotate(90);
Bitmap rotatedImage = Bitmap.createBitmap(sourceImage, 0, 0, sourceImage.getWidth(), sourceImage.getHeight(), mat, true);

Always i Run this code, my App crashes and says “VM won’t let us allocate xxxxxx bytes”

Can you help me?

Edit:

I saw much similar questions here, but i don’t know how to recycle the sourceImage before rotatating it… (cause the second instance is to big to hold it at the same time)

Thanks.

Answer 1

You can’t create a new rotated bitmap without holding temporary 2 bitmaps in memory.

But you can display the bitmap rotated without creating a new bitmap (apply a transformation).

ImageView does not come with rotation capabilities, so you should write your own extended version of ImageView (RotatedImageView?).

The idea is to override the onDraw method with something like this (not tested).

@Override
public void onDraw(Canvas canvas) {     
    canvas.rotate((int)(angle * 180 / Math.PI), getWidth() >> 1, getHeight() >> 1);
    super.onDraw(canvas);
}