Hello,

 

 Is it normal to see alot of striping within a trr3 image after running the volcano scan? I understand that cirrus operations are not required for most trr3 scenes, but I feel I may need to apply another operation to remove the prevalent striping within the image. However, the cirrus operations produce an image which is completly blank (black). I have been able to reproduce a somewhat similar image shown in the browse product section of the 0000CE1D image by applying the max /min pixel values specified in the the 'Map/Stretch info' section for the 'ir_maf' browse product of the 0000CE1D scene. However, this image also has additional hazy blue lines which do not show up in the official browse product shown on the website.

 

Any help would be much appreciated!

 

Regards,

 

Colin

Colin,

 

You need to re-stretch the CIRRUS output. It contains very large values at bad pixels. In the display window for the CIRRUS output go to  Enhance/Interactive Stretching (like before). First go to "Options" in the window that pops up and change the histogram parameters to reasonable values (maybe 0 to 1, you can experiment with this) and then reset the Stretch limits to something reasonable (experiment here too). Do that for all three RGB channels.

 

Any time you get an all-black output image in the CAT/ENVI processing, restretching the image is a good first thing to try. If you really have all zeros there's a problem, but usually it's just ENVI scaling to 65535 or a hot pixel or something.

 

As for the striping, there is frequently a little minor striping in the summary parameters. I'm not sure why it's showing up in the CAT and not in the published browse image, unless the resolution of the png is just not enough to capture it.

 

Frank