Mapserver and the fly conversion of 24bit RGB raster images to 8bit colormapped format

[Frank Warmerdam]

On 6/13/05, sylvain.perrinel <sylvain.perrinel at agriculture.gouv.fr> wrote:
> Hello,
> I'm trying to make a map with an ecw layer. But, Mapserver does not want
> to convert my 24bit RGB ecw image to 8bit like documentation says :
> http://mapserver.gis.umn.edu/doc35/raster-howto.html#rgb_color_cube .
> 
> Gdal support ecw format and the commande "gdalinfo" on the ecw layer
> stops on the color table and doesn't say anything. I think it tries to
> recover the table color !

Sylvain,

When you say "stops on the color table", do you mean that it 
starts to report a color table?  Then hangs?  I am surprised if there
is ever a report of a color table on ECW bands by gdalinfo.  However,
the hang behavior is fairly common with some versions of the ECW library
on Linux and I think relates to some sort of race condition in the
multi-threaded
stuff in the ECW library.  Upgrading to the latest ECW library may help in this
regard.

Best regards,
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