Posted by
Jennifer West on
Jul 11, 2006; 8:14pm
URL: http://imagej.273.s1.nabble.com/Image-quality-evaluation-tp3695062p3695063.html
Hi Emmanuele,
By chance I was working on this very problem yesterday!
I wrote a plugin that computes a "quality factor" based on a method
that I read at this site:
http://acquerra.com.au/astro/software/ppmcentre/According to the webpage, this method is the same as the one used in
Registax.
I've only tested my plugin on two stacks of images (one of Jupiter
and one of Saturn) and it seems to work reasonably well. But I would
be very happy if you would like to test it and let me know how it
works on your images. I've just posted it to my website and you may
download it here:
http://www.umanitoba.ca/faculties/science/astronomy/jwest/plugins.htmlMy next step is to write a plugin that will automatically select the
images with the best quality and create a new stack.
Let me know how this works for you!
Jennifer
******************************************************
* Jennifer West
* Observatory Assistant/Outreach Coordinator
* Glenlea Astronomical Observatory, Campus Office
* 378 University College
* University of Manitoba
* Winnipeg, MB R3T 2M8
* P 204.474.9501
* F 204.261.0021
* www.umanitoba.ca/observatory
******************************************************
On 11-Jul-06, at 10:01 AM, Emmanuele Sordini wrote:
> Hello everybody,
> I am a new ImageJ user and ML member. My main interest in ImageJ
> stems from
> my amateur astronomy activities (astronomical imaging and image
> processing).
>
> Let's suppose the following scenario: I have a set of 16-bit B/W
> frames of
> the same target (typically, a planet or a deep-sky object) that
> have to be
> registered, sorted for quality and stacked. The biggest problem I'm
> faced
> with is what image quality indicator should be used for reliable
> sorting.
>
> The image quality metric should be easy to figure out and not very
> demanding
> in terms of computing power; yet, it should somehow reflect the
> relative
> abundance of details and features on the current frame, which (if
> I'm not
> mistaken) should result in relative abundance of high-frequency
> components
> in the FFT domain. The literature mentions quite a few "one-number"
> quantities: RMSE, SNR, peak SNR, and so on... but I'm quite
> puzzled. I've
> also come across some "perceptual indicators" which integrate
> quantitative
> measurement and quality as perceived by the human eye, but I'd
> rather not
> venture into this domain for the moment.
>
> Any ideas/suggestions/links/references on the subject will be
> highly valued.
>
> Thanks in advance,
> Emmanuele Sordini
>
> P.S. Should anybody be interested in my amateur astronomy work,
> please feel
> free to check out my website: www.bloomingstars.com