[Image-SIG] Locate The Center of WhiteDot from a Image

[Christopher Barker]

On 1/7/11 10:14 AM, Narendra Sisodiya wrote:
> This Code Look for bounding box which I am calculating by scanning each
> row and column one by one. If I am finding any white pixel, I am
> including it into my bounding box.

> 1) there may a change that 2 or more WhiteDOT may present. One is Big
> whiedot and other are very smaller whitedot(just 2-3 pixel) near to this
> Big whitedot.

Not sure about this one off the top of myhead, but I"d suspect some 
smoothing may take care of it.

> I am applying this
> algorithm on every frame taken from camera at 2fps. So I want a high
> speed algorithm. PIL must be having some function or trick to do it.

The Image..getbbox() method should do it.

If you need more math, numpy can help. Somethign like:

a = np.asarray(PIL_image)
background_color = 0
rows, cols = np.where(a <> background_color) # background color a uint32
BB = (rows.min(), rows.max(), cols.min(), cols.max())

-Chris



-- 
Christopher Barker, Ph.D.
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