[gdal-dev] JPEG format.

[Frank Warmerdam]

Belaid MOA wrote:
> That's excellent to know! Thanks a lot Martin. Instead of getting segfault,
> I could use that to exist peacefully in case the driver does support the 
> Create() function.
> 
> Just of out of curiosity, why JPEG driver does not have the create 
> function and only supports CreateCopy()?
> The Create() function could be easily implemented using MEM and 
> CreateCopy(); instead of relying on the user to do this every time a 
> JPEG driver is used.

Belaid,

Many of us work with images that would be impractical to hold in memory,
and that might be quite inefficient to first marshall on disk in a directly
creatable format like TIFF.

The Create/CreateCopy distinction in writing with drivers is an important
one within GDAL and something that developers (and even to some extent
users) are expected to learn something about even if it is not immediately
obvious.  I do think it is addressed in the FAQ.

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