I need advice on how to complete the following task:
I have aeronautical charts covering parts of the US
(example: http://aeronav.faa.gov/content/aeronav/sectional_files/Albuquerque_89.zip - Each zip contains ~2 files covering both the northern and the southern part of the area).
Unfortunately for me, these maps have collars that I want to remove so that I could create a new geotiff file with only the real content of the original geotiff.
I have tried Global Mapper's "Crop collar" command, but that didnt gave me the results I wanted to have.
In my understanding I should use a tool like GDAL warp to complete this task in bulk for all of the images (~106 images in total), but the situation is that I am completely inexperienced using that tool.
I have already tried running
gdalwarp -srcnodata 0 -dstalpha input.tif output.tif but that didn't gave me good results as well, therefore I would be glad to receive some help!
Thanks in advance