06-14-2017 02:50 AM
Dear Community members,
I have problem with black fill around images.
Images delivered by Digital Globe comes divided to tiles.
I have used Mosaic Pro to merge tiles in to one IMG files and I forgot to set up parameter "Ignore Input Values" to 0 on Output Options tab under Output file name dialog.
Resulting IMG has black fill around images. All pixels in black fill have value 1
Is there any way to change pixel value of all pixels where all 4 bands have value 1?
Solved! Go to Solution.
06-14-2017 03:28 AM
Hiya. You shouldn't need to mosaic these tiles; DG data should come with a .TIL file that you can use natively within IMAGINE. If you use File > Open Raster Layer you will need to put an * in the file selector box to expose the .TIL file. Select it, it will create pyramid layers and you can use it as if it's a single file. Essentially you can treat it as a virtual mosaic.
06-14-2017 05:52 AM
I know about ,til but i have already created img files and created block file with that IMGs. Now I have to perform orthorectification of IMGs, but I whant to remove black fill if it is possible.
06-14-2017 07:05 AM - edited 06-14-2017 07:29 AM
A quick Spatial Model which changes pixels where all bands equal 1 to 0 instead, should fix the problem.
In fact you may also want to make sure that 0 is then set to NoData (using the Set to NoData operator).
06-19-2017 07:19 AM
The attached Model should do what you need. It checks for pixels where all four bands are DN value 1, sets those to a value that shouldn't be in use in a DigitalGlobe image, converts that value to NoData and then (assuming you are outputting an IMG file) uses 0 as the value-based NoData in the output file.
06-19-2017 07:53 AM
Not really. An iterator would evaluate the bands independanlty, whereas you need to evaluate them in combination / simultaneously to identify all the 1,1,1,1s. You could probably do it, but it wouldn't be elegant. Possibly better to use Stack Total = Number of Bands and Stack Diversity = 1.