srtm data analysis

Question

I need help to analyse the SRTM DATA (1025 X 1025) of a particular terrain which has gaps or voids.

Could anybody suggest a solution to find the percentage of gaps or voids in the SRTM data? I would like to know if there is a tool for such data analysis?

It is also possible for me to share the data if needed.

The file format is (.geotiff)

DanPatterson_Retired · Answer

you can also use the con reclass approach to get rid of extraneous values, then  Regiongroup  the areas and use Nibble to bleed values in from the edge of the holes  This is documented in the help files

curtvprice · Answer

SRTM data has gaps mostly from terrain effects (radar shadows) - not [usually anyway] the atmosphere.

If you can identify the cells that are "gaps" by their value (poke around with the identify tool) then you can classify your tiff into two classes like this using the Raster Calculator tool:

Con("srtm_raster" > 1000, 0, 1)

You can then convert the raster to polygons and from there you can calculate areas. You may need to convert multipart polygons to single part (there's a tool for that) to get areas for each individual blob.

I'm assuming your tiff doesn't have NODATA cells. If the gaps are not crazy values but actually classified as NODATA, you would then do it this way:

Con(IsNull("srtm_raster"), 0, 1)

DanPatterson_Retired · Answer

file still can't be downloaded...is this thread not finished?