Opened 14 years ago

Closed 8 years ago

#541 closed defect (fixed)

GDAL/OGDI driver does not read ADRG images correctly

Reported by: christik@… Owned by: warmerdam
Priority: lowest Milestone:
Component: GDAL_Raster Version: unspecified
Severity: normal Keywords:
Cc:

Description (last modified by Even Rouault)

I am attempting to use gdal_translateto translate between ADRG format and 
GeoTiff format.  A typical command line that I am using looks like this:

gdal_translate -of GTiff 
gltp:/adrg/C:/Kevin/NH1206/TLUS0101:"TLUS0101.IMG":Image out.tif

The output of this command is:
Input file size is 15616, 11136
0...10...20...30...40...50...60...70...80...90...100 - done.

Note that the size that it reports for the input file (15616x11136)
is, in fact, correct.  That is the size that I want the output file
to be (since that is the size that the input file is).

This command does generate a (679 Megabyte) 'out.tif' file, which is 
indeed the correct 15616 x 11136 pixels in size. Unfortunately, there 
is only 1000 x 1000 pixels worth of data in that file.  In other words,
the output file looks like a 1000 x 1000 pixel image that was expanded
/ zoomed to 15616 x 11136 pixels - it's very, very blocky.  Note that 
if I use gdal_merge.py (instead of gdal_translate) to translate the 
ADRG image to GeoTiff, I get the same behavior.

I am guessing that the ADRG reader is reading in the 15616 x 11136 
pixel source image and then squishing it down to 1000 x 1000 pixels 
so that it will fit through the OGDI bridge / OGDI gateway. After 
the (squished) image passes through the bridge/gateway, the GeoTiff 
writer then expands the image back to its full 15616 x 11136 pixel 
resolution before it writes it to the output file.  Unfortunately, 
most of the image data is lost in this process.

Can things be changed so that the image is passed through the OGDI
bridge/gateway at its full resolution, so that data loss does not
occur?

If you have any questions or comments, or want me to do some additional
testing, etc., feel free to contact me at christik@fhu.disa.mil.

Thank you very much!

- Kevin Christiansen

Change History (2)

comment:1 Changed 11 years ago by Even Rouault

See #1877 where a new ADRG driver is proposed directly in GDAL (no need for OGDI bridge)

comment:2 Changed 8 years ago by Even Rouault

Description: modified (diff)
Resolution: fixed
Status: newclosed
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