Question

I have this function:

public static Bitmap getResizedBitmap(Bitmap bm,Context c) {

    int width =(int) dp2px(bm.getWidth(),c);
    int height = (int) dp2px(bm.getHeight(),c);
    float scaleWidth = ((float) 250) / width;
    float scaleHeight = ((float) 170) / height;

    // create a matrix for the manipulation
    Matrix matrix = new Matrix();
    // resize the bit map
    matrix.postScale(scaleWidth, scaleHeight);
    // recreate the new Bitmap
    Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, false);

    return resizedBitmap;
}

where dp2px is:

private static float dp2px(int dip, Context context){
    float scale = context.getResources().getDisplayMetrics().density;
    return dip * scale + 0.5f;
}

It is ok on most screens but, for example, on galaxy s3 it returns

java.lang.IllegalArgumentException: x+width must be <= bitmap.width()

on this line:

Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, false);

Answer 1

It’s complaining that you’re trying to get a pixel outside the range of the bitmap. It could be just a rounding issue. Perhaps your calculated width is a pixel bigger than the actual bitmap width. What happens if you don’t add the 0.5f in your dp2px() function?