Re: Megapixels and noise

On Sep 27, 2:08 am, John Sheehy <J...@xxxxxxx> wrote:

Anyone have a nice function to simulate photon noise? I can do it in
Mathcad, but Mathcad only does poisson noise (and most other noises) by
creating a vector of poisson-distributed errors based on a single input
value, and to take an actual RAW file (or computer-generated image) with
low noise and simulate a much lower photon capture, I have to use Mathcad's
built-in function with each call for each pixel going through the process
of creating a vector (which is very slow), and then extracting one of its
elements to replace the original pixel.

I would like a function newval=poisson(val,scale) where scale is the
floating point number to scale the input (val) before creating poisson
error.


How about this:
http://www.cedarcreek.umn.edu/tools/utility/rpoisson.d.pdf
(I have never used mathcad so don't know how it works).

.

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