Water / blend mask dimensions

[arvisam 0]

Hello!I am doing some tests with imagery (NASA Blue Marble) and water masks (SWBD). I am using multisource INF file with 2 sources: source1 is the imagery and source2 is the mask. Both files are GeoTIFF, but their dimensions vary vastly. The BlueMarble imagery sources are around 21600x21600 pixels in size, while my generated SWBD mask files are much smaller (around 2048 pixels is what I was using.)Long story short and to the point: I found through trial and error that if the source dimensions and scales are not matched (basically unless I cropped the BlueMarble and mask sources to the same size and scale) the mask is not computed correctly.To summarize: Is there any way I can apply a much smaller mask on much larger imagery sources?Thank you,Arvind.

[Guest LCSims]

I don't recall ever seeing anything that mentioned the blend mask being smaller than the source file, so I don't believe that limitation can't be overcome. What I would do is take the source image and slice it into smaller pieces, maybe up to five if necessary, depending upon the area that needs the blend mask. One of these pieces contains the area that needs the blend mask and from that I would make one. Then you can recompile as a multisource into a single BGL file.That should work, because I have some material that I'm planning to approach in this manner. I believe water masks can be dealt with in the same manner.