Why ignoring -o option when use -jpegcrop?

[andrushka]

Why ignoring -o option when use -jpegcrop and overwrite source files? With -crop option is worked fine, but slow. ?

[DOS386]

Why ignoring -o option when use -jpegcrop and overwrite source files?

I don't see any blocker here, apparently for some "internal" reasons , could be improved

With -crop option is worked fine, but slow.

But also lossy

Possible implementation problem with lossless JPG transformations: http://newsgroup.xnview.com/viewtopic.php?f=35&t=19014

[helmut]

As written in another article, the direct manipulation of the lossless JPG operations is a problem in XnView (GUI), because it works differently and I guess there's users who crop and loose their original files by accident. The solution for XnView (GUI) would be a backup copy mechanism, which is a good idea, anyway.

The solution for nconvert seems even simpler to me:
Make a copy of the file, rename the copy to the specifed output filename, and then apply the lossless operation.

Anyway, this issue should be solved soon to avoid more people loosing part of their images due to a wrong usage.