Changed the commandline call to work with ffmpeg installed via macports (it couldn't see the PATH environment variable set up for macports and so couldn't find ffmpeg)
Also fixed image saving to use a valid FreeImage flag (JPEG_QUALITYGOOD)
change to use users PATH for ffmpeg, fix jpeg quality flag
Thanks for the commit! I'm glad you got it working on mac.
As for the quality flag, according to the freeImage documentation, any integer [0-100] can be used to specify quality. I will add a quality parameter to the setup function so it can be changed by the user.