There are actually three levels in the UI. Each one more advanced than the other. The first level, is the first screenshot and it’s meant for newbies. The second level, is the second screenshot and it’s meant for intermediate users. The third level is the “configure codec” and “customize command line” popup dialogs which will be different for each codec and only experts should use.

I would understand it like this: When I click “Custom” Button, the current preset is shown in the form, and when I change it, and select another preset, my changes are discharged, but when I click the “Disk/Store” Button, A dialog pops up where I can enter a new preset Name.

Example from PAL-Land:
Video from a DV-Camcorder is 720×576. But a square pixel TV Image has 768×576 Pixels. You do not scale directly though, but you scale to 788×576 Pixels, and then chop of 10 Pixels on the left and right. Don’t ask me why, but appearently this is some legacy thingy, and I find it really hard the present that in a user interface without lengthy explainations.

Your suggestion looks much better. The “custom” view is already an advanced feature, so it’s good that it offers enough options.

Hopefully once they port it to QT4 we’ll continue to see this application mature rapidly. As you say, it’s the only serious app of its kind for Linux today. And a very good addition to the Linux desktop that would help to take it to a higher level.