[IPOL discuss] [IPOL] new version demo NLmeans

[Guoshen Yu]

Hi José Luis, hi Jean-Michel and Toni,
Thanks very much for asking. I find the interface superb and it would be
great if our DCT denoising can have a same demo like this. Just two
remarks/questions. 

1. The denoising algorithm uses a noise sigma parameter. Is this parameter
estimated from the noisy image or is it simply copied from the interface?
The noise estimation and the denoiser can be considered as two completely
different algorithms, whereas the precision of noise estimation has a
direct impact on the denoiser performance. If this demo is to test the
denoiser, I think it would be better to directly copy the sigma as if it is
given. Moreover, in most denoising benchmarks, sigma is assumed known. If
in this demo the noise sigma is estimated, the comparison with the other
benchmark results will be unfair, in favor of most other benchmark results.


2. I think it would be really great if we can have an interface where a
number of denoising algorithms are simultaneously and systematically tested
together. For example, by clicking a button, all the algorithms are
executed and their results on the same image are displayed one next to the
other. I would be very happy to have the DCT denoiser bundled with any
denoising algorithm if possible. 

Jose Luis, thanks again in advance for implementing the DCT denoiser demo!

Best,
Guoshen

On Wed, 09 Mar 2011 17:36:25 +0100, José Luis Lisani
<joseluis.lisani at uib.es> wrote:
> The updated version of the NLmeans demo is available:
> 
> http://demotest.ipol.im/~lisani//bcm_non_local_means_denoising/ 
> <http://demotest.ipol.im/%7Elisani//bcm_non_local_means_denoising/>
> (user: demotest, passw. demotest)
> 
> The demo features:
> - subimage selection
> - result images displayed with a zoom in when they are small (less than 
> 200 pix. in any dimension)
> - all the images displayed on the same frame
> 
> It remains a pending issue:
> the use of 'float' images to prevent the loss of information due to 
> quantization
> (Nicolas?)
> 
> 
> @Guoshen: tell me if you like this kind of demo for your dct_denoising 
> algorithm
> 
> 
> Best,
> José Luis