Error Concealment | JPEG | MPEG-4 | Wavelet | YUV

Dear All 

I have a textured image(256x256) with a black rectangular shadow(around 30x 30) at the center
of image.Colud anyone suggest me some ideas to locate the shadow in the image and its width.

Thanks in advance 
yours
sigma

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An edge detect should do the trick but you need to decide on which of
the channels (R, G or B) or maybe all to run the edge detect on.  even
better again you could try converting to an alternative colour space 
YCbCr or something.  Some of these other colour spaces have individual
channels (in this case Y) which will show a change in illumination
much better than say a channel to do with any particular colour or
chrominance.  Please dont assume from this that YCbCr is the right
option im just using it as an example

Rob

--- In i...@yahoogroups.com, ayyappanmani@... wrote:
>
> Dear All 
> 
> I have a textured image(256x256) with a black rectangular
shadow(around 30x 30) at the center of image.Colud anyone suggest me
some ideas to locate the shadow in the image and its width.
> 
> Thanks in advance 
> yours
> sigma
>

(You need to be a member of imagedsp -- send a blank email to imagedsp-subscribe@yahoogroups.com )