Project a raster

810
7
04-02-2014 01:37 AM
Highlighted
New Contributor
Hi,

I have downloaded data from here http://bioval.jrc.ec.europa.eu/products/gam/download.htm for a masters project.

I am fairly new to altering projections, but for the work I am doing I am using a Lambert Azimuthal Equal Area projection with Central_Meridian: -0.53528 and Latitude_Of_Origin: 8.675451 as my work is focused on West Africa (please correct me if this does not make any sense/is not the correct way to get equal area in a specific region).

My issue is that all of my other datasets (including rasters) have reprojected fine from WGS84 to the above projection, but when I attempt to project the above dataset it comes back with a generic error and that "the operation was attempted on an empty geometry". On other posts I have read that this can be because the original projection was not defined but I have checked and it it is definitely in WGS84.

Any suggestions as to why I can't gt this to project?

I also had an initial problem that it would not display but on looking through the forums this was due to pyramids already being drawn and once the .rrd file was removed it draws.

I am using 10.1 with SP1.

Many thanks

Ali
Reply
0 Kudos
7 Replies
Highlighted
Esri Notable Contributor
Hi Ali,

I'm trying to download the dataset now. Meanwhile, the picture of the dataset is in the Robinson projection, not a geographic coordinate system. What extents does it have? If you add just this data to a new map, what does it look like?

Getting "empty geometry" sometimes means an incorrectly defined coordinate system on the input dataset. The software interprets the coordinates according to the coordinate system, but they don't actually make sense.

Melita
(data is 1/3 downloaded...)
Reply
0 Kudos
Highlighted
New Contributor
Hi Melita,

Good point! I've checked but I'm pretty sure it is WGS84. Extents are
<Top>89.9999999993
<Left>-180
<Right>179.999999999
<Bottom>-90

And it says the following for spatial reference
<Spatial_Reference>GCS_WGS_1984
<Angular_Unit>Degree (0.0174532925199433)
<Datum>D_WGS_1984

Many thanks for looking at this
Reply
0 Kudos
Highlighted
Esri Notable Contributor
I managed to download it--but it doesn't display. All the values look fine, no scale-dependent display turned out, etc. I'm not a raster specialist though! Right now I'm converting it to a different raster format to see what happens.

Melita
Reply
0 Kudos
Highlighted
Esri Notable Contributor
Ali,

Try converting the raster to a different format. I converted it to a file gdb (not recommended) by right-clicking the grid in the table of contents and selected, data, export data--took all defaults. The new raster showed up fine in the map, in decimal degrees.

Melita
Reply
0 Kudos
Highlighted
New Contributor
Hi Melita,

I tried changing it to a grid but it came back with the same error when I tried to project it. Any other suggestions?!

Ali
Reply
0 Kudos
Highlighted
Esri Notable Contributor
Change it to a tiff or jpeg instead. I used the default file geodatabase, but I'm not sure what raster 'format' that is.

Melita
Reply
0 Kudos
Highlighted
New Contributor
Hi Melita,

So I have managed to get it to work. If I clip the original file to my area of interest and then project it, the projection will work.

I'm not really sure why this works or if this is the correct thing to do!!

Ali
Reply
0 Kudos