Image resizing efficiency in C# and .NET 3.5

Question

I have written a web service to resize user uploaded images and all works correctly from a functional point of view, but it causes CPU usage to spike every time it is used.

Answer 1

Image processing is usually an expensive operation. You have to remember that a 32 bit color image is expanded in memory into 4 * pixel width * pixel height before your app even starts any kind of processing. A spike is definitely to be expected especially when doing any kind of pixel processing.

That being said, the only place i could see you in being able to speed up the process or lowering the impact on your processor is to try a lower quality interpolation mode.