POV-Ray : Newsgroups : povray.binaries.images : Sampled photo in RGB space Server Time
7 Nov 2024 09:25:42 EST (-0500)
  Sampled photo in RGB space (Message 1 to 5 of 5)  
From: Bald Eagle
Subject: Sampled photo in RGB space
Date: 16 Jul 2016 20:45:05
Message: <web.578ad438c52748bd5e7df57c0@news.povray.org>
I sampled an image_map pigment of a photo of my son with eval_pigment, and
plotted the resulting vectors in RGB-space (step 10 in x and y).
The scanning takes 33 sec (2448 x 3264).

I want to find a way to "cluster" similar values - I'm experimenting with
rounding the RGB channels, etc.

I also made a sort of "parametric" RGB map - translate along x by gray, rotate y
by green, then x by red, then z by blue


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From: tth
Subject: Re: Sampled photo in RGB space
Date: 22 Jul 2016 17:09:42
Message: <57928b96$1@news.povray.org>
On 07/17/2016 02:41 AM, Bald Eagle a dit:
> I sampled an image_map pigment of a photo of my son with eval_pigment, and
> plotted the resulting vectors in RGB-space (step 10 in x and y).
> The scanning takes 33 sec (2448 x 3264).

    I've done something like that, but with some C and shell coding.

    Original video is here :
http://la.buvette.org/photos/myrys/20ans/avance-rapide.avi

    (gory) C code is here :
http://la.buvette.org/vrac/colorcube.c

    And the result is here :
http://la.buvette.org/photos/myrys/20ans/fx/colorcube.avi

> I want to find a way to "cluster" similar values - I'm experimenting with
> rounding the RGB channels, etc.

    I'va also done (a long time ago) some search in this field

> I also made a sort of "parametric" RGB map - translate along x by gray, rotate y
> by green, then x by red, then z by blue

    Mmmm, sound nice :)



-- 
http://weblog.mixart-myrys.org/?post/2016/03/De-la-temporalisation


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From: Bald Eagle
Subject: Re: Sampled photo in RGB space
Date: 22 Jul 2016 21:10:00
Message: <web.5792c33271d66b005e7df57c0@news.povray.org>
tth <tth### [at] noneinvalid> wrote:

>     And the result is here :
> http://la.buvette.org/photos/myrys/20ans/fx/colorcube.avi

That's quite a fascinating video!

I do believe I'll be watching that many more times as I investigate all of the
ways to manipulate and analyze color and it's usage in my scenes.

It's quite interesting to see how your graph is so similar to mine - that long,
unvarying stretch across the "gray diagonal" and then you get a rising of a
"spine" in the Green, and some clusters in the Red and Purple, and a big blob in
the Yellow and Orange at certain points.

I may see if plotting colors in HSV or other "color spaces" gives more
interesting results.  Given some more work, I think some of the graphs of color
are nice looking things in their own right.

Very nice work - I really like the overlay of the color graph on the video.

Thanks for sharing!  :)


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From: Jörg "Yadgar" Bleimann
Subject: Re: Sampled photo in RGB space
Date: 24 Jul 2016 00:07:12
Message: <57943ef0@news.povray.org>
Hi(gh)!

On 22.07.2016 23:09, tth wrote:

>    Original video is here :
> http://la.buvette.org/photos/myrys/20ans/avance-rapide.avi
>
>    (gory) C code is here :
> http://la.buvette.org/vrac/colorcube.c
>
>    And the result is here :
> http://la.buvette.org/photos/myrys/20ans/fx/colorcube.avi

Stunning! As I also started experimenting with time-lapse videos, I 
would like to ask you:
- how long was the timespan the camera filmed (obviously all through the 
night and a good part of the bright daytime before and after)?
- which picture rate did you use?
- and how was the camera powered? Plugged to a car battery?

This is the longest time-lapse video I created so far, a three-hour 
bicycle ride around Cologne, Germany, but with several stops for battery 
change: https://www.youtube.com/watch?v=0A9ASULLEN8

See you in Khyberspace!

Yadgar


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From: tth
Subject: Re: Sampled photo in RGB space
Date: 25 Jul 2016 05:56:14
Message: <5795e23e$1@news.povray.org>

> Hi(gh)!
>
> On 22.07.2016 23:09, tth wrote:
>
>>    Original video is here :
>> http://la.buvette.org/photos/myrys/20ans/avance-rapide.avi
>>
>>    (gory) C code is here :
>> http://la.buvette.org/vrac/colorcube.c
>>
>>    And the result is here :
>> http://la.buvette.org/photos/myrys/20ans/fx/colorcube.avi

    http://la.buvette.org/photos/myrys/20ans/fx/raytraced.avi

>
> Stunning! As I also started experimenting with time-lapse videos, I
> would like to ask you:
> - how long was the timespan the camera filmed (obviously all through the
> night and a good part of the bright daytime before and after)?

    From saturday 3PM to sunday 5PM, approximatively

> - which picture rate did you use?

    Around twenty secons between frames, iirc.

> - and how was the camera powered? Plugged to a car battery?

    No, pictures are grabed on a Linux box, with a
    playstation's USB camera.

>
> This is the longest time-lapse video I created so far, a three-hour
> bicycle ride around Cologne, Germany, but with several stops for battery
> change: https://www.youtube.com/watch?v=0A9ASULLEN8
>
> See you in Khyberspace!
>
> Yadgar


-- 
http://weblog.mixart-myrys.org/?post/2016/03/De-la-temporalisation


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