IMG2PNG, PDS/FITS to PNG conversion Options

[S_Walker]

Thanks everyone for the help. It seems the images in question are indeed 8-bit png, if I'm reading the actions correctly.

[Bjorn Jonsson]

Correct, the input images are 8 bit. But there's one important thing I forgot to mention, "-r". You need to include this when running img2png to get it to calibrate the input files. Like this:

img2png *.img -r

[machi]

Original image from Cassini's ISS can be 8-bit, but if you use img2png with calibration, than output is 16 bit png. Without calibration procedure is output 8 bit png when original is 8 bit image, or 16 bit png, when original is 12 bit image.

BTW, I tried new user-specified calibration procedure on old Voyager images.
It looks, that img2png accept well my calibration files, but new version can't read and convert imq files (old version has no problems with them).

[S_Walker]

Thanks everyone for the help. Works great now.
Emily, I realize cosmic ray hits wouldn't go away with calibration; I'm so used to my own deep-sky imaging where multiple sub exposures are combined to both increase the signal, as well as average out CR hits; same goes for my own planetary images taken with my camera and telescope. Not as used to putting planet images together with single exposures.
I was hoping the faint "venetian blind" artifacts would be removed with calibration (horizontal bands that are barely above the background counts), but alas, it's not to be.

[ugordan]

I was hoping the faint "venetian blind" artifacts would be removed with calibration (horizontal bands that are barely above the background counts), but alas, it's not to be.

Yeah, the 2Hz banding is hard to remove as it's not predictable. I don't think even the imaging team has a good solution to this. Basically involves advanced filtering of the image (helps if you have "black" areas around targets of interest) and is therefore not part of the standard calibration procedure.

[Bjorn Jonsson]

BTW, I tried new user-specified calibration procedure on old Voyager images.
It looks, that img2png accept well my calibration files, but new version can't read and convert imq files (old version has no problems with them).

That's weird, converting imq files works perfectly on my end, both with and without a calibration file. Are you using the most recent beta version? If yes (or if the most recent version does not work either) please post the error messages (if any) that appear plus a screenshot similar the the one posted by S_Walker at the top of this page (or, using copy-paste, the text from the command prompt window).

[Juramike]

OK so...

New img2png programs unzipped - check
Cassini calib "Index of /volumes/COISS_0011/CALIB" calib.tar.gz unzipped and put in C:\\ directory - check (did I need to use the V2 version instead?)
moved mottlemap_hack.img into c:\calib\dustring folder - check
put img file and lbl file in same folder as img2png_new.exe - check
command script run - looks same as above - check (using -r option):



but png file is jet black (N1652854565_1.IMG):


Ran on another file (W1652951881_1.IMG) got noisy picture:


Did run OK on Galileo image.

Did I mess up the Cassini calibration files somehow?
(These are both coming out as 16-bit PNG's)

[Juramike]

Part II:

Looked at log files. Needed to download instead the "2011_v2" volume instead. Did that. Modified the ".ini" file to point to the nested calibration files".
Tried it again, got same result as above.

Screenshot of log files show that the "c:\coiss_0011_v2\calib\offset\nacfm_so_p5.img" filesize is wrong (also WAC version)? The files show in my c:coiss_011_v2\calib\offset" directory as an 8K file.

[Bjorn Jonsson]

I wonder if the calibration volume didn't get decompressed correctly. If you use WinZip to decompress you have to be careful (I don't think this has changed in recent WinZip versions). I don't know about different decompression programs. See this message for details.

[Juramike]

Thanks! I'll try that this evening! I used the WinZip defaults when I unpacked the calibration data.

(To turn off the TAR file smart CR/LF conversion it is in the WinZip "Options/configuration/Miscellaneous/other" box.)

-Mike

[machi]

That's weird, converting imq files works perfectly on my end, both with and without a calibration file. Are you using the most recent beta version? If yes (or if the most recent version does not work either) please post the error messages (if any) that appear plus a screenshot similar the the one posted by S_Walker at the top of this page (or, using copy-paste, the text from the command prompt window).

Here it is.

Attached thumbnail(s)

 

[Bjorn Jonsson]

The issue with the IMQ files has now been fixed and I have uploaded a new version.

The problem was that the IMQ files have at least two different header 'variants' and I hadn't noticed this. The new version checks the headers more carefully than the old version does (this is to avoid misidentifying some files). It didn't recognize the Voyager Neptune headers but in contrast, e.g. Voyager Jupiter was OK. I don't think there are more variants of the IMQ file headers but cannot rule it out completely.

[Juramike]

Awesome! It now works for me! Whoo-hoo!
(Bwa-ha-ha!)

[machi]

It looks, that it's now working fine. Thank you Björn!

[Bjorn Jonsson]

The IMG2PNG beta version discussed in recent messages (in particular here) has now become an 'official' version. There are no significant changes from recent versions of the beta so it may not be necessary to upgrade it. In contrast, I recommend this new version of img2png for anyone using the old version, especially if there have been any hints of problems.

See http://www.mmedia.is/bjj/utils/img2png for more information.