Re: [Gimp-developer] JPEG lossless operations?

[Ofnuts <ofnuts laposte net>]

On 05/30/2012 05:55 PM, Bruce wrote:

I've read that Picasa (Google's program) might be able to perform lossless rotations, but I'm just going by what I've read. (Source) 

Apparently there are ways to test if the tool you use makes use of lossless rotation. This page lists some:  http://www.impulseadventure.com/photo/lossless-rotation-test.html 

This page also has a nice explanation of lossless rotation and its finer nuances:

http://www.betterjpeg.com/lossless-rotation.htm

From what I've learned so far, I think in the end you just have to relax about all this stuff and not worry about it too much, though it does help to know what's happening when you do certain things (such as rotate a jpeg). 

The best (and fastest....) way to rotate a JPEG is to change its orientation flag...