[Qgis-user] Four band raster displaying funny

[Jukka Rahkonen]

Jonathan Moules <jonathanmoules at ...> writes:

> 
> 
> Hi List,
> I've got a 4 band raster aerial photography (RGBI) that comprises lots of
tiles. I've merged some of the tiles together with:
> 
> 
> 
> gdal_merge -o 1.tif -of GTiff -co TILED=YES -co BIGTIFF=YES -co
COMPRESS=JPEG -co JPEG_QUALITY=50 -co BLOCKXSIZE=512 -co BLOCKYSIZE=512
--optfile tiff_list.txt

Are you sure that after running that command you have a 4-band image? I have
believed that JPEG compression can be used only for 1- or 3-band images.
What does gdalinfo report about your image?

I would have a try by using LZW or deflate compression and annex for example
a screenshot about the settings you have been using for selecting the bands
and adjusting histogram stretching etc.

-Jukka Rahkonen-