[gdal-dev] Re: gdalwarp -of JPEG

[Jukka Rahkonen]

Craig Leat <craig.leat <at> gmail.com> writes:

> 
> Hi,
> 
> I have noted with gdal 1.6.1 that gdalwarp -of JPEG returns the error
> message "Output driver `JPEG' not recognised or does not support
> direct output file creation." However, gdal_translate -of JPEG works.
> Is there any justifiable reason that gdalwarp does not support writing
> JPEG or is wrapping JPEG inside GTiff the usually way of doing things?
> 
> Thanks for any insights,

Hi,

I believe that in warping process data needs to be written in arbitrary places
into the output image and that can be impossible or ineffective if the target
image is jpeg compressed.  I guess it might be done somehow when simply warping
one whole image to another projection as it is, but gdalwarp can do other nice
things like warping from virtual mosaic or warp new data into an existing output
image. Let gdalwarp create an uncompressed tiff first and compress it to jpeg
afterwards. I bet it is also the fastest way do get the job done.

-Jukka Rahkonen-