[Gdal-dev] ecw-compressing >500MB files

[Tom Lynch]

On 5/13/05, Ken Boss <Ken.Boss at dnr.state.mn.us> wrote:
> Under FWTools 0.9.8, I can successfully use gdal_translate to generate
> an ECW output from a 400 MB input file.  If I try to do the same with a
> 750 MB input, however, I get:
>
> gdal_translate -of ECW -co target=95 two_tiles.tif two_tiles.ecw
> Input file size is 18988, 14016
> 0.100 - done.
> ERROR 4: `d:\ken_mrsid\test_tiles\two_tiles.ecw' does not exist in the
> file syst
> em,
> and is not recognised as a supported dataset name.
>
> I'm guessing this might owe to input file size limitations, but looking
> at the ECW 3.1 SDK page at http://www.ermapper.com/ecw/ and the price
> list at http://www.ermapper.com/document/doc.aspx?doc_id=54, I'm left
> with the distinct impression that the free GPL-style license for the SDK
> (surely this is what gdal uses?) provides unlimited compression.
>
> Can anybody clarify this for me?

Thanks Frank, you have it right on the use of ECW_LARGE_OK I'm sure.

Brent, GDAL does currently use the version of the ECW JPEG 2000 SDK
that is made available under a "GPL-style" license (there are a couple
of differences with the GPL).  The GPLish license only comes into play
when using unlimited compression, otherwise the source and binary
distributions of the ECW JPEG 2000 SDK are for free use.

There's a relevant buglog:

http://bugzilla.remotesensing.org/show_bug.cgi?id=767

--
Tom Lynch
Development, ER Mapper
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