Scaling Bitmap on the fly. For Android, including main thread, background thread and Glide examples.

ScaleBitmapExamples.java

    //Scale function:
    
    /**
     * Creates new bitmap by scaling given one
     *
     * @param scaleFactor
     * @param bitmap
     * @return new bitmap
     */
    public static Bitmap createScaledBitmap(Bitmap bitmap, float scaleFactor) {
        Matrix m = new Matrix();
        m.setRectToRect(new RectF(0, 0, bitmap.getWidth(), bitmap.getHeight()),
                new RectF(0, 0, bitmap.getWidth() * scaleFactor, bitmap.getHeight() * scaleFactor), Matrix.ScaleToFit.CENTER);
        return Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), m, true);
    }
    
    
    // Example of usage im main thread:
    Bitmap scaledBitmap = UIHelper.createScaledBitmap(letterTile, 2f);
    
    // Example of usage in background thread
    new Thread(new Runnable() {
                @Override
                public void run() {
                    final Bitmap scaledBitmap = createScaledBitmap(letterTile, 2f);
                    getActivity().runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            anyImageView.setImageBitmap(scaledBitmap);
                        }
                    });
                }
            }).run();
  
  //Example of usage with Glide:
    Glide.with(getActivity()).load(playableItem.getCoverImageUrl()).crossFade().into(new GlideDrawableImageViewTarget(imgDetailedTopCover) {
        @Override
        public void onResourceReady(GlideDrawable drawable, GlideAnimation anim) {
              super.onResourceReady(drawable, anim);
              Bitmap bitmap = ((GlideBitmapDrawable) drawable).getBitmap();
              anyImageView.setImageBitmap(createScaledBitmap(bitmap, 2f));
        }
    });