Re: Not getting Poisson Noise in octave

[c.]

On 3 Dec 2012, at 00:05, Terry Duell wrote:

> You could also try something like this...
> 
> bb = aa + 3/256*randn(h,w);
> where h,w are the height, width of aa.
> 
> The first approach takes 13.74 sec here, for my little test image. The second 
> takes about 0.01 sec.
> The results appear quite similar, but I guess it depends on your particular 
> need.

that is equivalent to 

bb = imnoise (aa, 'gaussian', 0, sqrt(3/256))

which works the same in Matlab and Octave, the version I proposed 
is equivalent to 

bb = imnoise (aa, 'poisson')

which is not yet implemented in Octave:
http://octave.sourceforge.net/image/function/imnoise.html
http://www.mathworks.it/it/help/images/ref/imnoise.html

whether it is equivalent to use either of the two indeed depends on the OP's 
particular application.

> -- 
> Regards,
> Terry Duell


c.