topic Reprojecting rasters in Data Management Questions

Reprojecting rasters

BenLeslie1 — Wed, 06 May 2015 07:25:04 GMT

Hello Geonet

What's the best way to reproject multiple rasters i.e. tiff tiles that cover a county region.

When I reproject tiles individually I get black edges on all the images from the rotational correction. So I'm considering merging all the images into a single tile before doing the reprojection - this is feasible in this case but for a larger area would not be possible; so what's the best route to take?

Thanks,

Ben

Re: Reprojecting rasters

JakeSkinner — Wed, 06 May 2015 11:18:14 GMT

Hi Ben,

I would recommend creating a mosaic dataset with the projection you would like the rasters projected in. You can then load the rasters into the mosaic dataset, and set a geographic transformation (if necessary) by right-clicking on the mosaic dataset > Properties > Defaults tab:

Re: Reprojecting rasters

JayantaPoddar — Wed, 06 May 2015 11:33:33 GMT

Hi Ben,

If the black edges are "NoData" values, you could use Reclassify tool. Select all the records except "NoData" and click Delete Entries

Define the new values to 0.

Re: Reprojecting rasters

BenLeslie1 — Wed, 06 May 2015 12:53:49 GMT

Hi Jake, this is definitely useful - I've learnt somethin new. However, I ultimately need to output to tiffs so it looks like I will still need to mosaic the mosaic into a single tiff and then chop it up into tiles - do you agree?

Re: Reprojecting rasters

JakeSkinner — Wed, 06 May 2015 13:19:22 GMT

If you require TIFFs, I would recommend running the Project Raster tool. In order to get rid of the blank edges, you can set the NoData value within the Environments. I'm assuming the values 0,0,0 are being converted to the black edges. If this is the case, you can set the NoData value to 'MINIMUM'. This will convert the 0,0,0 values to NoData. Ex: