Folks -
This is my first post to this mailing list. My apologies if this is a real stupid question. I am new to apple systems ( my last one was an Apple 2e ) and working these days on a Power Mac ( I think ). with quartz composer.
First - let me explain where I am. I am a grad student working on a matlab application that works perfectly for High Dynamic range imaging. The application works ok where it is - that is in MatLab, you have access to the entire image at all times.
The project I am on is porting this application to the quartz composer environment. At this time, after breaking thru and decomposing older modules into yet smaller modules, I ran into a basic snag.
The snag I have is, in
changing color spaces, The original matlab code would convert the image into a 3 By long matrix. The three would be the RGB for each pixel, and the Long is width times height for the image itself. Effectively each color plane of the original image is converted into a column vector. This 3 by long is multiplied IN SOME CASES by a simple 3 by 1 matrix in order to effect a colorspace change. in other cases this is a 3 by 3 matrix.
In my newness ( read clueless newbie druid ), I thought I could simply grab a blank image structure, stuff it with the transformed image, Matrix multiply the result and then push the data back into the conventional format for handling in the beyond.
Not So.
One reason is in QC, you do not have the whole image at all times - this box runs for pixels, like shaders of procedural shading classes of
yore. I can see converting a single pixel into a 3 by 1 RGB data block and then applying a 3 by 1 color change matrix, but I think I need 3 pixels of data to run with the 3 by 3 color change matrices. ( See Question 1 )
A second area is - If I am processing just a pixel worth of data at a time, I do not think I need to reconfigure the data as I am doing in the old model. I would like to see what I am doing. Is it possible in QC to kludge errrr.... uhhhhhh fashion a widget that just displays data values? I could run the section with minimal code and data volume to confirm correct operation before dropping a plethora of data all over it.( See Question 2 )
If you think these are troublesome - several of the modules have Fast Fourier ( "Fast and Furious" ) Transforms in them. Those questions will be later.
Right now - I am looking
over some convolution code from the web.
Question 1: Is it possible to hang on to data in QC? say three pixels worth?
Question 2: Is there any way in QC to be able to see the numerical results of ones incantations upon the demons?
All replies and assistance welcome. Curses employing obscenities or colloquialisms must be spelled correctly. All flames cheerfully ignored.
Many Thanks.
--dan
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Power corrupts, but we still need the electricity"
