Opened 16 years ago

Closed 15 years ago

#443 closed enhancement (fixed)

No Data Value for three band images

Reported by: fosnight@… Owned by: ersts
Priority: major: does not work as expected Milestone: Branch - Raster Transparency
Component: Rasters Version: 0.8
Keywords: raster no data Cc:
Must Fix for Release: No Platform: All
Platform Version: all Awaiting user input: no


A common kludge for three band satellite images is to reserve either 0,0,0 or 255,255,255 for no data. Many satellite images have significant background data. To mosaic images effectively requires a mechanism to make the nodata areas transparent.

Attachments (1)

QGIS images with no data.png (150.7 KB ) - added by fosnight@… 16 years ago.
screen shot of mosaicked images

Download all attachments as: .zip

Change History (6)

by fosnight@…, 16 years ago

screen shot of mosaicked images

comment:1 by cavallini@…, 16 years ago

Platform Version: Mac OS X 10.4.8all

in reply to:  1 comment:2 by fosnight@…, 16 years ago

Replying to

see also my wish:

A more general proposal would certainly be preferred. Transparency is not handled elegantly within scientific systems. As formats, PNG and TIFF do about the best for RGB images. My preference within QGIS would be to set the value for each band as a metadata/symbology property. Old school but simple and independent of raster format.

comment:3 by wonder, 16 years ago

Milestone: Version 0.8 ReleaseVersion 0.9 Release

comment:4 by ersts, 15 years ago

Awaiting user input: unset
Milestone: Version 0.9.1Branch - Raster Transparency
Owner: changed from timlinux to ersts

This is being addresses in the raster transparency branch and is largely completed. Feedback on the modification in the branch from the original poster of this ticket would be great.

comment:5 by ersts, 15 years ago

Resolution: fixed
Status: newclosed
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