Tiff resampling and logging problem in PHP/Mapscript

[Frank Warmerdam]

On 6/15/05, Gambin Dejan <Dejan.Gambin at pula.hr> wrote:
> Hi,
> 
> I would like if someone can tell me how can I see if resampling of tiff
> raster data occuring or not? The logging feature is not working for me
> in PHP/Mapscript. I have set a LOG and DEBUG parameter in map file but I
> haven't got any output. Then I saw a bug 709 that discusses this
> problem. I have set CONFIG MS_ERRORFILE mapserver.log instead of LOG
> parameter and I have seen it is being filled but no resampling messages
> appear. Must I have some kind of debug build to enable logging?
> 
> I took a look in source code and it seems as the resampling occurs only
> if the source image is rotated or the map and layer projections differ?
> Is it so or am I seing things wrong?

dg,

If you are seeing outher debug messages in the log, and no
message about msResampleRasterLayer or something like
that then it is not being done.  As you note, it only kicks in
when the image is rotated or there is an apparent difference
in the projections.

Note that the default image render case does do simple downsampling
type of resampling.  The Resample case really implies that a pixel by
pixel warp is applied during the resampling stage instead of simple
decimation in x and y. 

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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