Re: Not getting Poisson Noise in octave

[c.]

On 3 Dec 2012, at 05:44, Terry Duell wrote:

> Hello Carlo,
> 
> On Mon, 03 Dec 2012 14:56:00 +1100, c. <address@hidden> wrote:
> 
>> 
>> 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:
> 
> [snip]
> 
> OK, then I should not be making any changes to the imnoise code.
> 
> Cheers,

On the other hand I see now that poissrnd does accept a matrix as input, so:

poissrnd (aa)

works fine and is much faster than my previous version
I'll have a look at changing "imnoise" accordingly.

c.