Seadas HDF Expor to ArcGIS Format - NV5 Geospatial

Prev Go to previous topic

Go to next topic

Last Post 24 Sep 2008 08:34 AM by anon

Seadas HDF Expor to ArcGIS Format

2 Replies

Sort:


You are not authorized to post a reply.

Author

Messages

anon

New Member

Posts:

24 Sep 2008 08:34 AM
Hi: Sorry fer my delayed reply. I tried your recommendations without success. I am going to explain the procedure in more detail. 1. Downloaded L3 MODIS K490 images(4Km). 2. Open it in ENVI 4.4, it is an HDF dataset 3. Use a ROI to make a spatial subset of the global image. Load the Image. Save Image as (tried: ENVI, ERDAS, GEOTIFF, etc.) 4. Open ArcMap 9.3. Load image (warning of unknown spatial reference appears). Load shapefile (data in State PLane NAD 83 or I use another shapefile WGS 1984 projection). Dont see the shapefile so I use Full Extent. I notice the image is far from my shapefile and it is larger in scale. 5. Use build statistics to the image. Define projection to Geographic WGS-84 (Still no overlap of the image with my shapefile. Reload a another image, define the projection to NAD 83 StatePlane FIPS 5200 PR_USVI, no success. 6. I tried this procedure with all xported formats without success. I noticed that probably is a problem with the extent or tie points of trhe coordinate system. In ENVI, when I tried to edit the Map Info in the header file it reads (WGS-84) in the Map Coordinate of Tie Point area. It also has 2 open spaces to put the coordinates of tie points (dont know what number to put in there). Also the pixel size and rotation is empty. Please advice so what procedure might help with this. Thanks William

MariM

Veteran Member

Posts:2396
Veteran Member

24 Sep 2008 09:30 AM
If the image is not georeferenced, then when you export it to ArcGIS, it isn't georeferenced either. When you open the image in ENVI, does it report a projection? If not, then use the Georeference MODIS tool, or use the MODIS toolkit and output the image in a projection that is useful for you. The image will then be in ENVI format and be projected. Subset this image and then import this directly to ArcGIS. No need to 'export' as Arc 9.3 will recognize the ENVI format.

Deleted User

New Member

Posts:

29 Sep 2008 07:23 AM
The image is a L3 MODIS 4KM image. It has a projection of WGS1984 although it does not have the Map Coordinates Tie Points values. I opened the image and selected the K490 product (since the image is in HDF format) then I tried the MODIS GEOREFERENCE Tool and gives me an ERROR "The selected MODIS HDF file does not contain SD datasets for Latitude and Longitude" I also tried the tool after ,making the image subset using ROI's, but it would not work because it is not MODIS HDF format. However, I downloaded the MODIS Toolkit and the Ocean Color toolkit and installed them. The Ocean Color Toolkit converted and projected the MODIS L3 image into ENVI format. Then I created a subset of the data via ROI's. The image will not show up in AddLayer in Arcgis so I used ENVI to load the band in display and selected Save as Image file. I saved it ENVI format and loaded the file in ArcGIS and the data ovelapped perfectly with my shapefile. The only thing is that the Saved Image data in ArcGIS is in the scale of 0-255, and in ENVI, before saving it to Image File, has values Max/Min values of 1/Kd of 0.1686-0.02324 (REAL VALUES). I also tried saving it in different formats without success. Thanks for your reply.

You are not authorized to post a reply.