re: never take a blurry pic again

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k - 26 Nov 2005 01:15 GMT

re: Never take a blury photo again

..and here's more on how it all works:

http://graphics.stanford.edu/papers/lfcamera/
http://graphics.stanford.edu/papers/fourierphoto/

hmm..

OK, it's still something that could be achieved by using scanned negs from
film based technology mebbe

.. then we could pop a microlens array between the lens and the *film* in a
film camera, scan the resulting image and perform the same trick with film
media ..

that'd be nice!

http://en.wikipedia.org/wiki/Fast_Fourier_transform

fft info - I like this explanation:

"By far the most common FFT is the Cooley-Tukey algorithm. This is a divide
and conquer algorithm that recursively breaks down a DFT of any composite
size n = n1n2 into many smaller DFTs of sizes n1 and n2, along with O(n)
multiplications by complex roots of unity traditionally called twiddle
factors"

k

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Noons - 26 Nov 2005 02:27 GMT

k apparently said,on my timestamp of 26/11/2005 12:15 PM:

> fft info - I like this explanation:
>
[quoted text clipped - 3 lines]
> multiplications by complex roots of unity traditionally called twiddle
> factors"

of course! :)
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k - 26 Nov 2005 21:35 GMT

| re: Never take a blury photo again
|
| ..and here's more on how it all works:
|
| http://graphics.stanford.edu/papers/lfcamera/
| http://graphics.stanford.edu/papers/fourierphoto/

or....

..and for those of us without microlens arrays in front of our sensors who
want to make infinite or variable dof images, theres free software :)

http://www.heliconfocus.com/pages/index.php?focus_overview

"HeliconFocus is a program that creates one completely focused image from
several partially focused images by combining the focused areas. The
program is designed for macrophotography, microphotography and hyperfocal
landscape photography to cope with the shallow depth-of-field problem.
Helicon Focus also aligns images as objects often change their size and
position from shot to shot. This function is especially important for
macrophotography"

"Helicon Filter is shareware.
You can download and use the program for evaluation purposes for 30 days.
After the evaluation period the program will switch to Free mode with
limited functionality (see details below).

"Helicon Focus (Lite - basic version):

- automatically adjusts and resizes images (important for stereomicroscopes
and macrophotography);
- processes an unlimited number of images in the stack;
- has no limitation on image resolutions (you need at least 512M RAM to
work with 8Mp+ images);
- supports "dust map" to automatically remove black points from the
resulting images;
- automatically adjusts brightness of the adjacent images;
- reads RAW, 8bit and 16bit TIFFs, JPEG, JPEG 2000, BMP, etc;
- writes 8bit and 16bit TIFFs, JPEG, JPEG 2000, BMP.

Helicon Focus Pro (advanced version):

- includes all the features of the Lite version;
- generates opacity maps for further processing in Adobe PhotoShop;
- adds text title and scale to the image;
- will contain more advanced features in the future.

k

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