MrSID mapserver vs gdal_translate

[Frank Warmerdam]

Simpson wrote:
> Hi,
>
> I find gdal_translate about three times faster than mapserver when
> processing a small area from a MrSID file.  If I add a class definition to
> the layer in the map file, the results are black and white, but the image
> renders at about the same speed as gdal_translate.  Is this disparity in
> time a result of bands being extracted separately?

Drew,

Yes, the performance issue is related to MapServer reading each band
seperately.

What I really need to do is modify mapdrawgdal.c to use the "several bands
at once" interface to GDAL (relatively new in GDAL) to accelerate performance.
But doing this will mean a non-trivial restructuring of the code so I have
put it off.

Best regards,
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