[Gdal-dev] ECW small problem

[Tom Lynch]

On 2/3/06, Ivan Mjartan <ivan.mjartan at geovap.cz> wrote:
> Hi all,
>
> I have one question about minimum size of ECW raster
>
> I tried create small ecw files and I tested that is no possible create
> smaller raster than 130*130px.
>
> So what is possible minimum size of ECW?
<snip>

Ivan,

ECW files have a minimum size of 128 x 128 pixels.  This is due to
certain assumptions made by the encoder.  Of course, given the
application area of the format (large imagery) this isn't much of a
limitation :-)

JPEG 2000 files don't have any such size restriction and can be as
small as 1x1 pixel.

I can't comment on the error you received from GDAL, except to state
that ECW files only ever use 8 bits per component per pixel (all data
is stored as unsigned 8 bit integers internally), so it seems likely
that it's erroneous.

Tom.

--
Tom Lynch
Development, ER Mapper
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