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4th rock from th...
post Dec 15 2014, 11:04 PM
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There's no contrast variation, but the petals are traceable if you look for texture variation.
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alex_k
post Dec 16 2014, 08:38 AM
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Something like this?
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4th rock from th...
post Dec 16 2014, 10:37 AM
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Alex_k, most of what I see on that image is just small scale noise generated by processing.

You are processing the image at a higher resolution than the original.
So any "details" that become apparent but are below the original pixel size are just noise.
I'd recommend using a low pass filter on the end result to remove them.

Anyway, you can more or less trace the petal outlines by small changes on the noise pattern.
Makes sense because even if covered in dust, they are still smother that the surrounding soil.


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alex_k
post Dec 16 2014, 11:33 AM
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QUOTE (4th rock from the sun @ Dec 16 2014, 03:37 PM) *
Alex_k, most of what I see on that image is just small scale noise generated by processing.

Details of the lander become distinguishable, don't they?
QUOTE
You are processing the image at a higher resolution than the original.
So any "details" that become apparent but are below the original pixel size are just noise.

Actually not a correct conclusion. Because neighbour pixels can also contain information, especially if a camera had a little disfocus. So it's possible to extract information from them - to acceptably approximate the "pixeled" image.
QUOTE
I'd recommend using a low pass filter on the end result to remove them.

If to use a low-pass filter before processing we'll lose details.
You're right that there're some artifacts in the resulted image. They can be avoided by using a low-pass filter after processing.

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4th rock from th...
post Dec 16 2014, 02:22 PM
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Yes, low pass at the end, after all filters.

On this case, the best option would be contour filters and rainbow / spectrum palettes instead of grayscale.
Those bring out structure and small contrast variations without changing the original values.

Exaggerated filtering will give you false details due to pixel value rounding errors that then get amplified over and over.

This is small example. The word "detail" printed on a small font size.
Right top is 3x resample. The "t" starts to show a false curved appearance, but in general, resolution seem to improve.
But heavy filtering (right bottom) gets you ringing artefacts and just false details (for example, a thin line connecting the "a" to the dot on the "i" as appeared.).
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Just my 2cents, just trying to help, rolleyes.gif


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alex_k
post Dec 16 2014, 02:56 PM
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QUOTE (4th rock from the sun @ Dec 16 2014, 07:22 PM) *
Exaggerated filtering will give you false details due to pixel value rounding errors that then get amplified over and over.

Of couse in general you are right. But it depends on the source image and filters to be appllied. "Over and over" without limitations will get pure noise. smile.gif
Another question is about information in subpixels - can it be extracted and how.

upd: for testing the method I found appropriate pair of of images, low-res for processing and hi-res for comparing: http://www.esa.int/spaceinimages/Images/20.../Boulder_Cheops
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You can estimate whether the details false or not.
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mcgyver
post Dec 16 2014, 06:51 PM
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QUOTE (djellison @ Dec 15 2014, 11:24 PM) *
What I find odd in this is

What is actually odd is that ANYthing is visible after 17 years. :-)
Only the airbag close to ramps is high enough to get dust off it naturally; the others are quite flat and so probably totally covered by dust.
In the enhanced gif one of them is also in shadow.
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djellison
post Dec 16 2014, 07:36 PM
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QUOTE (mcgyver @ Dec 16 2014, 10:51 AM) *
What is actually odd is that ANYthing is visible after 17 years. :-)


The backshell and parachute as well as the landers are visible from both Viking missions, now 37 years old.

Your suggestion that the piece we see is the only piece tall enough to get dust blown off it....

http://photojournal.jpl.nasa.gov/jpeg/PIA02652.jpg

The piece of airbag to the -Y side of the -X petal is SIGNIFICANTLY larger and taller than the piece by the +Y petal.

The reason that one piece stands out in HiRISE is because of the metallic foil tangled up in that piece of airbag.

I believe a similar piece is tangled up off the end of the +X petal - but one would need to be observing at a different time of day to get a glint off that ( and due to orbital mechanics, that's unlikely ).

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PDP8E
post Dec 19 2014, 05:54 PM
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Thanks guys, I am looking into the petal problem at the moment (good catch!) as it relates to this image

But like I said: its the worst case super-res possible: working from a single image.
As the Hirise camera sweeps the area, a single pixel will get contributions from many surrounding sub-pixel and super-pixel objects (some dark some brighter) as well as each particular pixel characteristic, the pixel read-out artifacts of the camera, point spread functions in the system, time of day shadows, and other messy issues. And only then do we get to work with the released images.

But I do aim to improve my process as time allows (and thanks for the feedback!)


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djellison
post Dec 19 2014, 06:05 PM
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There are at least two HiRISE images that cover the MPF lander - and one even got it in color ( and so is thus actually 3 images! )

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PDP8E
post Dec 19 2014, 06:11 PM
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I am on it Doug! smile.gif


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4th rock from th...
post Dec 20 2014, 02:44 AM
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PDP8E, how is it possible to have super-resolution from a single image?

Or do you mean deconvolution techniques?


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sittingduck
post Dec 20 2014, 02:22 PM
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PDP8E, I really enjoyed your 'simulated' super-resolution image. From what I understand you're working to make a genuine multi-image super-resolution rendering of the Carl Sagan memorial station. I don't know how much work that involves, but I would like to ask you to consider creating similar image of the mpl heatshield and parachute/backshell as well. I ask because I combined color information with your previous super-resolution product and am pleased with the result, and think it would be worthwhile for the other pieces of hardware. Probably it is my imagination, but it almost looks like you can make out the golden-color of the ramps.
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PDP8E
post Jan 3 2015, 07:22 PM
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Hey 4th Rock, and SittingDuck

I call it super-res but you are right -- it really is super-deconvolution

I am working on the items you want SittingD, BTW your color image is superb!

More later!


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RichforMars
post Jun 4 2015, 02:39 PM
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Can the MRO ever get a much closer view of the craft?
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