Ticket #3513 (closed defect: fixed)

Opened 3 years ago

Last modified 3 years ago

Can't open this USGS DEM

Reported by: gaopeng Owned by: warmerdam
Priority: normal Milestone: 1.8.0
Component: GDAL_Raster Version: 1.6.1
Severity: normal Keywords: usgsdem
Cc:

Description

Attached should be a USGS DEM. But GDAL can't open it. It looks like it has wrong header info.

Attachments

fixed.dem Download (401.0 KB) - added by gaopeng 3 years ago.

Change History

Changed 3 years ago by gaopeng

Changed 3 years ago by warmerdam

  • keywords usgsdem added
  • status changed from new to closed
  • resolution set to fixed
  • milestone set to 1.8.0

The file is somewhat non-standard. In particular it uses -9999 and -9 for fields like coordinate system and units that it has no particular idea about. I have made adjustements to the driver to support this file in trunk (r19267) and 1.6-esri (r19268).

Changed 3 years ago by gaopeng

  • status changed from closed to reopened
  • resolution fixed deleted

This DEM should have no spatial reference. But it returns a real (wrong) SR, instead of none.

Changed 3 years ago by warmerdam

  • status changed from reopened to closed
  • resolution set to fixed

I have made an adjustment to treat this sort of file as having no coordinate system in trunk (r19283) and 1.6-esri (r19284).

Changed 3 years ago by gaopeng

  • status changed from closed to reopened
  • resolution fixed deleted

Another problem. The DEM should be 200x200 looking like a circle. But currently only half of the image is visible, and the rest are considered bad.

            fscanf(poGDS->fp, "%d", &nElev);
            if (iY < 0 || iY >= GetYSize() )
                bad = TRUE;

Changed 3 years ago by warmerdam

  • status changed from reopened to closed
  • resolution set to fixed

The problem turned out to be another place assuming not PROJCS must measured in arcseconds. Fixed in trunk (r19291) and 1.6-esri (r19292).

Note: See TracTickets for help on using tickets.