Archived posting to the Leica Users Group, 2007/06/12

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Subject: [Leica] Lilies - jumping on the bandwagon - Neat Image
From: douglas.sharp at gmx.de (Douglas Sharp)
Date: Tue Jun 12 01:18:26 2007
References: <000001c7ac0d$6553ede0$5c00640a@MADS> <466D29E8.8050303@gmx.de> <9b678e0706111738m6ef0c7b4j21860a4b14b6d578@mail.gmail.com>

Hello, Don
thanks for your kind comments.

Neat image offers (almost too many options) for noise reduction and 
sharpening in 3 different bands and a selection of whether to do it in 
RGB or YCrCb - the second option means you can sharpen in the luminance 
channel alone and avoid most of the sharpen artefacts found with other 
programs. The options, as far as I understand the fundamental idea of 
it, are low, medium and high-pass filters and when you set to 
"conservative" sharpening this probably prevents clipping around the 
respective Nyquist frequencies or cut-off points for the respective 
filters, or it tapers the flanks of the spectra more strongly. I also 
suspect that the noise filters are in reject mode with a mix-back 
function and that sharpening is purely pass - only the programmer knows, 
and he must be good.

On the other hand, it may be some clever use of FK filtering (frequency 
/wavenumber) or a deconvolution process, or a complex random noise 
attenuation program, but one thing is clear to me, whoever worked it out 
hasn't been looking at pictures, it's all physics and math that ALSO 
works on images. In spectral analysis, digital technologies couldn't 
care less whether it's a signal, a frequency or a colour - it's all just 
numbers.
I only wish I had had something as efficient as Neat Image for cleaning 
up noisy seismic data.

http://www.neatimage.com/

Cheers
Douglas


Don Dory wrote:
> The end result is very nice indeed.  When you say you sharpened in three
> frequencies I would appreciate a little more information on that.
>
> On 6/11/07, Douglas Sharp <douglas.sharp@gmx.de> wrote:
>>
>> So many lovely lilies!!!
>> Motivation enough to go deep into my "back catalogue" of flowers to dig
>> up some of my own.
>>
>> A little abstract, and far removed from a garden context - hope you like
>> them.
>>
>>
>> http://gallery.leica-users.org/v/DMS/New-Old-Pictures/_MG_1143_edited-2.jpg.html
>>  
>>
>>
>> http://gallery.leica-users.org/v/DMS/New-Old-Pictures/_MG_1182_edited-3.jpg.html
>>  
>>
>>
>> http://gallery.leica-users.org/v/DMS/New-Old-Pictures/_MG_1091_edited-6.jpg.html
>>  
>>
>>
>> http://gallery.leica-users.org/v/DMS/New-Old-Pictures/_MG_1136_edited-3.jpg.html
>>  
>>
>>
>> Comments welcome
>> Douglas
>> (before anyone asks - yes, there was a fair amountIMG:  of Photoshopping
>> involved)
>>
>>
>>
>> >
>>
>> _______________________________________________
>> Leica Users Group.
>> See http://leica-users.org/mailman/listinfo/lug for more information
>>
>
>
>

Replies: Reply from hoppyman at bigpond.net.au (G Hopkinson) ([Leica] Lilies - jumping on the bandwagon - Neat Image)
In reply to: Message from mads.christensen at gmx.net (Mads Christensen) ([Leica] Water lilies)
Message from douglas.sharp at gmx.de (Douglas Sharp) ([Leica] Lilies - jumping on the bandwagon)
Message from don.dory at gmail.com (Don Dory) ([Leica] Lilies - jumping on the bandwagon)