What is the most effective format to manage aerial photography for viewing in ArcGIS?
I manage several datasets of Aerial Photography at a few different companies. I have backups of the original photography, so I'm not worried about keeping the original format in any way. What I need to do is create a small dataset, as too not take up much space on the server, that also draws as quickly as possible in ArcGIS.
So far I had been using GRID's in a File GeoDatabase, but that was just because I has assumed it was the standard. I then switched to TIFF's which were smaller, but seemed to draw slower. Before I do another mass conversion, I'm hoping someone can offer guidance on this. I've heard some great things about JP2's and that's where I am likely heading next.
Also I don't want to reduce cell size, but other than that I have no restrictions in any answer.
Answer
Generally I'd go with ECW over JP2 as the refresh rates for the ECW are better. There is MrSID to consider, but it is expensive - possibly more than ECW provided you're appropriately licensed, but at the extreme compression level (95% to 99%) they are clearer than similar ECW.
JP2 offers open source compressors, lossless compression and 4 band support (RGBA). A bit of a loss with aerial photography shouldn't matter too much; The alpha band can be great if you've got two scenes with irregular edges that need to be superimposed.
If you build the pyramids (use GDALAddO to build ovr files) for TIFF files they can be very fast too, and when you zoom in it depends on your compression (LZW, Zip, Deflate... many supported) as to how fast they are. There is a trade off between smaller sizes and CPU usage by using more intense compression and there is a possibility that some software will not like a particular compression method.
In the end JP2 is the best free format for aerial photography and IMHO ECW is the best paid format.
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