topic Re: Basics of Raster in Data Management Questions

Basics of Raster

JayKappy — Mon, 11 Mar 2013 14:33:00 GMT

I am confused...I am reading help and see Mosaic Dataset, Raster Catalog, Raster Dataset etc...
I want to take some SID files and mosaic them and create one SID file
I also want to so this with a Single TIff file and compress to jpg2000.
Do i create a Catalog? Dataset? (mosaic or raster)
Can someone help explain this for me....thanks

Re: Basics of Raster

JakeSkinner — Mon, 11 Mar 2013 21:03:16 GMT

Hi Jay,

When dealing with the SIDs, you will want to create a mosaic dataset. ArcGIS does not have the ability to write to the MrSID format. Also, SIDs are highly compressed, so when you mosaic them to another format they will be uncompressed. SIDs that are a few GBs on disk may be 100s of GBs when they become uncompressed.

Mosaic Datasets read the raster imagery in it's native format and does not make a copy of the raster. It processes the imagery on the fly and returns a mosaicked image. You will save an enormous amount of disk space and processing time creating a mosaic dataset.

As for the TIFF file, can you explain a little more? What type of raster are you trying to convert it to (.JPG, .TIF, etc)? Does it matter, or do you just need it to have JPEG2000 compression?

Re: Basics of Raster

JayKappy — Tue, 12 Mar 2013 13:09:06 GMT

So when would I use a Raster Catalog or Raster Dataset?

I have to Raw TIFF files that I am looking to convert to JPG2000, I found "gdal" open source conversion software that will do this...I have been told it does a far better compression job than esri software can..
Regardless...What would you recommend if I had 40 or so TIFF files and wanted to get them to JPG2000? What would ESRI recommended steps be? Would I use a Raster Catalog? Raster Dataset? I will want to mosic the output as well.

THanks

Re: Basics of Raster

JakeSkinner — Wed, 13 Mar 2013 14:59:13 GMT

So when would I use a Raster Catalog or Raster Dataset?

I can't think of scenario where you will want to use a Raster Catalog over a Mosaic Dataset. Mosaic Datasets perform much faster. As for a raster dataset, a good scenario to use these would be for outputs from geoprocessing tools. For example, if you ran the IDW tool, the output would be a raster dataset. Or, you could use a raster dataset when you need to work with a small individual raster.

If you plan to mosaic 40 TIFFs together and use them in ArcGIS, you would want to use a mosaic dataset.

Are you ultimately using the mosaic in ArcGIS, or do you need to use it in other software? If you need to use it in other software, what output can the raster be (or need to be), i.e. TIFF, JP2, JPEG, etc?

Re: Basics of Raster

JayKappy — Thu, 21 Mar 2013 13:51:03 GMT

I have a bunch of compressed jp2000 images with world files...
I want to mosaic them into one file....and remove the black stip that overlaps each image.
how do I do this and what output would be best...

I create a Mosaic Dataset in a Geodatabase and add a Raster....it shows up....
I add another and only the boudaries show up...the actual image no longer shows up????

THanks

Re: Basics of Raster

JayKappy — Fri, 22 Mar 2013 14:24:27 GMT

Anyone?
How do I mosaic and get rid of the black line for a bunch of JPG2000 files, while keeping the compression?
When I run a batch moasic it only brings in the bourdary lines...the images dissapear.
what am I doign wrong....

I am starting with a bunch of TIFF files and want to end up with one JPG2000 image.

If I can figure out how to mosaic the TIFF images and remove the black overlap line I will be ok...but cant figure it out...

Re: Basics of Raster

JakeSkinner — Mon, 25 Mar 2013 10:52:00 GMT

Jay,

After you add all the rasters, right-click on the mosaic dataset in the catalog window > Modify > Build Footprints. Accept the defaults and click OK. This will remove the black border around the images since the min and max data values defaults to 1 and 255 for this tool.

You most likely cannot see the rasters because you did not build overviews. After you build footprints, right-click on the mosaic dataset > Optimize > Build Overviews. Accept the defaults and click OK.