Importing a large file into ArcGIS

[katieclarke]

Hi All,

So I have an extremely large file that I need to import into ArcGIS. It is a 7gb tiff file, which is a DEM. I have tried compressing to a  7z file which I now realise you can't open in GIS anyway. Does anybody have an ideas on how I can make the file smaller to be able to import it? I am on university servers which doesn't help!

Cheers,
Katie

[808707]

ArcGIS can handle that size of file. Why don't you just open it straight in ArcGIS?

[katieclarke]

Maybe it's because I'm on a university computer, but it is extremely slow and eventually crashes. There is no way that a file of this size will open and run on the university computer.

[808707]

Ah i see it's more of a network problem.

Can you transfer the file to a portable harddrive or usb pen or even save it to the C: drive?

You'll overcome any network problems then.

[katieclarke]

It is already on my hard drive 😞 I think it is to do with the computing power. If you know a way to compress it so that it will still open in ArcGIS that would be great!

[808707]

Hello Katie. To be honest I don't think compressing it is going to make the file size that much smaller. You're still talking several GBs of data.

Is the file aerial imagery or a DEM?

Some other options might be to find the file in ArcCatalog then either to lower the resolution using the 'Resample' tool or split is into several rasters using the 'Split Raster' tool.

Failing that get in touch with your course lecturer and explain that you can't open the file on uni computers.

[katieclarke]

Hi,
I have spoken to my tutor about it. Unfortunately she isn't that clued up on GIS so doesn't really understand the problem.
It is a DEM, and it needs to be kept in the same res! :confused:
Can you expand on the split raster? That sounds more promising.

[808707]

Oh dear sounds like a bit of a farce. They should maybe check that you can actually do exericises on uni computers first!

Can you check with any other students on your course to see if they are having the same issue?

You can use the 'Split Raster' tool to split the raster into either a user defined size or an equal number of parts.

Have a go at setting the 'Split Method' to number of tiles then setting the 'Number of Output Rasters' to 3 in 'X Coordinate' and 3 in 'Y Coordinate'

You will end up with the raster split into 9 tiles. Have a go at opening one of these on your computer.

What is the ultimate aim of all this. Are you using surface modelling or hydrology tools in ArcGIS?

[katieclarke]

Ultimate aim is to be able to read the x, y, z co-ordinates and fit a plane to the base. Its for measuring the volume of lava around a volcano. Kinda have to be able to do it! There must be a way of compressing it haha. The only problem is, I can't actually get the DEM in to ArcGIS in the first place...the computer says no before its loaded. So I'm going to have to resolve this before I import it.

Have tried cropping in photoshop, but it looks a bit weird. Trying to figure out now if it has messed up the pixel size...

[808707]

Okay sorry I couldn't be more help.

Something else I just thought is you could download the demo version of ArcGIS and use it on a computer at home if you have one.