[Gdal-dev] Rotate an image

[Frank Warmerdam]

Geographic Wizard wrote:
> Hello, all.
>  
> What would be the best way to rotate an image with GDAL / Warp?
>  
> Do GeoTransform[ 2 ] and GeoTransform[ 4 ] have any effect on RasterIO ? 
> and are they related to rotation of an image?

Steve,

The geotransform[2] and [4] are honoured by the georeferencing based warper
so you could construct an input image with a world file with appropriate
rotational coefficients, and then use gdalwarp to "undo" the rotation.

The geotransform does *not* have any effect on raw rasterio calls.

Best regards,
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