[josm-dev] Download WMS layer as jpeg

[xancorreu]

Hi,

I'm a user of josm. I like it very much. Thanks for your job.
I want to use how to download WMS layer as jpeg, If you click right 
button then josm let you download layer as xml, ... and jpeg. But how? 
when I choose jpeg, the file is not jpeg (a simply run of file command 
confirm it)

If it's not possible in josm, is there any way to do it

Thanks,
Xan.