[Gdal-dev] Rotating images

[Frank Warmerdam]

On 9/14/05, Morten Nielsen <mn at blominfo.dk> wrote:
>  
>  
> 
> I am looking for a fast way to rotate an image just by adding the
> Orientation tag (274) to a tiff. My images are jpeg-compressed and tiled
> tiffs, so I'd rather not do a new recompression of the data. 
> 
>   
> 
> Is there an easy way of adding the tag using any of the GDAL commandline
> tools? (or any other way of rotating the images without recompression) 
> 
> I only need to rotate the images either 90, 180 or 270 degrees. 

Morten, 

The tiffset utility is intended to allow setting individual tags in an 
existing TIFF file.  I'm not sure if it supports orientation but it could
be easily adapted to do so.  Note that I think tiffset ends up writing
a new directory and losing the space for the old one.  But at least
it avoids rewriting the image data. 

Best regards,
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