Pablo Quemé February 2016

Scale Bitmap maintaining aspect ratio and fitting both width and height

I want to scale a bitmap maintaining the aspect ratio, but fitting the required dimensions. This answer scales the bitmap and maintains the aspect ratio, but leaves some blank space unless the image is a perfect square. I need to fill both width and height, just like the FIT_XY ScaleType property of an ImageView.

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Pablo Quemé February 2016

Based on Streets of Boston's answer, I made this method that scales and returns any Bitmap to a desired width and height, fitting both dimensions (no blank space!). It automatically adapts to more horizontal or more vertical images.

    public Bitmap resizeBitmapFitXY(int width, int height, Bitmap bitmap){
        Bitmap background = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        float originalWidth = bitmap.getWidth(), originalHeight = bitmap.getHeight();
        Canvas canvas = new Canvas(background);
        float scale, xTranslation = 0.0f, yTranslation = 0.0f;
        if (originalWidth > originalHeight) {
            scale = height/originalHeight;
            xTranslation = (width - originalWidth * scale)/2.0f;
        }
        else {
            scale = width / originalWidth;
            yTranslation = (height - originalHeight * scale)/2.0f;
        }
        Matrix transformation = new Matrix();
        transformation.postTranslate(xTranslation, yTranslation);
        transformation.preScale(scale, scale);
        Paint paint = new Paint();
        paint.setFilterBitmap(true);
        canvas.drawBitmap(bitmap, transformation, paint);
        return background;
    }

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Asked in February 2016
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