deconvolution for DSLR images

[spearo (Frank)]

Hi All,
I image with a Canon EOS 20Da.

Anyone know of a good (which means free) piece of software that I could use to process color images in deconvolution ?

thanks
frank

[iceman (Mike)]

Does IRIS do it?

Or AstraImage 3?

[Garyh]

Try PixInsight LE,
Its Trous Wavelet is pretty good.

[spearo (Frank)]

Thanks Guys,
I'll check them out
cheers
frank

[spearo (Frank)]

downloaded,
will play around with them tonight
cheers
frank

[netwolf]

IRIS should do this for you, but it has a steep learning curve. Well worth it i am told.
Pixinsight LE is another good option.
Also look at Stellar Magic, they have a freeware version. I have used this to combine RGB images for planet work. Dont recall if deconv is available in the free version or not though.
http://stellar-magic.com/download.html

Regards
Fahim

[Ian Robinson]

Get Matlab Student edition , deconvolution is easy to code .

[netwolf]

Ian, that is an excellent option. There are some free matlab clones out there also.
http://www.dspguru.com/sw/opendsp/mathclo2.htm

[Ian Robinson]

A little more detail : from my old signal processing notes-

A blurred or degraded image can be approximately described by this equation g = Hf + n,
where
g is the blurred image
H is the distortion operator, also called the point spread
function (PSF)
f is the original true image and
n is Additive noise, introduced during image acquisition, that corrupts the image.

In the spatial domain, the PSF describes the degree to which an optical system blurs (spreads) a point of light. The PSF is the inverse Fourier transform of the optical transfer function (OTF). In the frequency
domain, the OTF describes the response of a linear, position-invariant system to an impulse. The OTF is the Fourier transform of the point spread function (PSF). The distortion operator, when convolved with the image, creates the distortion. Distortion caused by a point spread function is just one type of distortion.

So you need to subtract n.
and then you deconvolveit.

The syntax is [q,r] = deconv(b,a) where b and a arrays and the results are matrix [q,r] = [g]-[n].

The rest is easy codingwize , just need to assign an acceptable n and H. How do you do that someone asks - a curvefit will do it , that will give you H and n. (Easy to do in Matlab).

[netwolf]

This is one example using Matlab.

http://www.mathworks.com/access/help...G=Search&meta=


You can also do this in IRIS.
http://www.astrosurf.com/buil/iris/new533/new533_us.htm

Ideally you could somehow capture the Impulse response of the imaging system and use that as the PSF. The image of a star perhaps.

Regards
Fahim

[spearo (Frank)]

Thanks Fahim and Ian,

I have much to learn and I'll play around with the software
cheers
frank

[Ian Robinson]

Originally Posted by netwolf

This is one example using Matlab.

http://www.mathworks.com/access/help...G=Search&meta=


You can also do this in IRIS.
http://www.astrosurf.com/buil/iris/new533/new533_us.htm

Ideally you could somehow capture the Impulse response of the imaging system and use that as the PSF. The image of a star perhaps.

Regards
Fahim

If I remember right - image processing toolkit is an addon to Matlab. (in V7 anyway) , been a few years since I used Matlab.

I might get a copy of IRIS , is it freeware ?

[netwolf]

Ian, yes IRIS is freeware. Its been almost 10 years since i used Matlab.