Which tool converts PDS4 Mars 2020 images to 16 bit/channel PNG or TIFF?

[Holger Isenberg]

I'm searching for software to convert PDS4 .xml/.img from of the Mars 2020 cameras to 16 bit/channel PNG, TIFF or other lossless formatted files.

So far couldn't find any which runs on current macOS: NASAView https://pds.nasa.gov/tools/about/pds3-tools/nasa-view.shtml is not available for current macOS, the Java-based transform only writes 8 bit (https://github.com/NASA-PDS/transform/issues/15), the Python PDS4viewer https://pypi.org/project/pds4-tools/ only writes 8bit as well and my years old PDS plugin for GIMP doesn't work on recent versions. The APIs used by transform and pds4-tools are most likely supporting 16 bit already, but before spending time to write my own software around those I like to ask here if something is available.

[June Wang]

Hi,

Please have a try of GDAL (https://gdal.org/index.html), which can read the PDS4 img and converted it to a 16-bit tif. You may need a high version of GDAL, which supports PDS4.
The version I used was 3.5.1 released on 2022/06/30. I tested on the mars2020 Super Camera Remote Micro Imager data with below GDAL command (https://gdal.org/programs/gdal_translate.html). It returned a 16bit GeoTiff.

gdal_translate -ot Int16 -of GTiff D:\test\data\mars2020\20200816\LRE_0080_0674037605_189ECM_N0032430SCAM02080_0340I6J04.xml D:\test\data\mars2020\20200816\LRE_0080_0674037605_189ECM_N0032430SCAM02080_0340I6J04_gdal.tif

Please let me know if you need more help. Thanks,

June

[Holger Isenberg]

That's great news, thanks! Works fine also for PNG 16 bit output I see:

gdal_translate -ot UInt16 -of PNG SOME_EDR.xml SOME_EDR.png

The resulting linear PNG and TIFF from EDR.imgs have intensity values 0 - 2033 which matches the tabulated 12/8 bit LUT for Mastcam-Z. That means the output is not stretched during conversion, which is best for correct calibration.

Installation on current macOS was also simple: brew install gdal

I see that it is also listed on https://pds.nasa.gov/tools/tool-registry/ when selecting transform / pds4, but I missed it due to the highly encoded description there as "translator library for raster and vector geospatial data formats" which didn't looked like some simple to use command line tool.

[June Wang]

Great. I’m glad it worked out.