Remove White Background from an Image and Make It Transparent

Question

We\'re trying to do the following in Mathematica - RMagick remove white background from image and make it transparent.

But with actual photos it ends up looking lous

Answer 1

I am completely new to image processing but here is what I get after some playing with new morphological image processing functions of version 8:

mask = DeleteSmallComponents[
   ColorNegate@
    Image[MorphologicalComponents[ColorNegate@img, .062, 
      Method -> "Convex"], "Bit"], 10000];
Show[Graphics[Rectangle[], Background -> Red, 
  PlotRangePadding -> None], SetAlphaChannel[img, ColorNegate@mask]]