As in the title, which is the fastest way to resize an image? I'm using Python + OpenCV 2.11 (not openCV3), and it seems `cv2.resize()` is very slow.

We can use CUDA with OpenCV3 (<http://www.coldvision.io/2015/12/22/image-resize-with-opencv-and-cuda/>), but is it supported in OpenCV 2?