Hi Alessio,

SORRY! I meant ZOOM OUT! Aargh. Pleace replace "zoom in" in my orginal post
with "zoom out".

The root cause seems to be that ImagePyramidReader only uses one axis to
determine the resolution level (the actual mosaic to use). It may happen
that in one zoom step the first axis is used for determining the level and
in the next the other axis is used. Now the resolution of the mosaic may be
different for the two axes and the second step returns a more detailed level
than the previous one despite the fact that the user zooms in. In my case
this happend when the geographic area for which I requested the data was
truncated.

Perhaps it is easier to understand with concrete code. 
I used my own implementation of ImagePyramidReader with the setReadParams
method overwritten. setReadParams has some minor modifications to take both
axes into account. I have uploaded the class.
http://www.nabble.com/file/p11115873/ImagePyramidReader.java
ImagePyramidReader.java  Currently the level with least detail is used (for
performance reasons). Perhaps it is useful to offer other possibilities of
level selection here (most detail, selection on estimated performance/detail
loss). Maybe one could use some user prvoided hint here? 

Cheers
Helge


Alessio Fabiani wrote:
> 
> Hi Helge,
> with the ImagePyramidReader if you zoom in more than the resolution
> provided
> by the pyramid, the reader should start doing some interpolation using
> Pyramid level 0 as image source. That could be the cause of the increased
> loading time I guess, is that the case you are talking about?
> If not, maybe you have found a bug ...
> 
> 

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