Cutting AVI's & Mpeg's While Keeping Quality etc.

1st Objective: To cut or edit out songs from a concert video into individual files while maintaining original quality.
When I do this with ...Adobe Premiere Pro7 or Ulead Video Editor, is there a quality loss? If so, is there a better way to do this?

2nd Ojective: Cutting out many unwanted video parts from original [ie commercials] while keeping original quality. Is it correct that to put the original "back together" less the unwanted video, I would have to re-encode the original therefore losing quality? If so, is there software that will allow me to keep original quality?

Related Question;

If I'm starting with a large, un-encoded AVI file, is it overall better for quality purposes, to first, convert it to MPEG2 before cutting or editing?

I have other related questions, but I'll wait. Thank you in advance.

 

When Cutting AVI and Mpeg Files in an editor like "Adobe premier Pro" there will allways be Quality loss because it has to re-encode the Files when rendering....

If you just want to do Simple Cutting and Joing of AVI Or Mpeg files you have to use an editor that can cut the files without and save them without re-encodeing them....

For AVI files you can use a Freeware program called "Virtual-Dub" when set to "direct stream copy" mode which can cut and join avi files without re-encodeing them but all cuts have to be on Key frames or you will have Sync problems and the audio can not be VBR MP3 format which is very common in Downloaded AVI files or the audio will also go out of Sync.....

For Mpeg-2 files you can use a Freeware editor like "Chopper XP" or "Cuttermaran" but you also have to make all cuts on I Frames which makes for not very accurate cuts, For Frame accurate editing of Mpeg files i like to use an editor like "Womble Mpeg2VCR" or "Womble Mpeg Video WiZard 2005" which can even add effects and transitions without re-encodeing the whole Project, It only re-encodes the Parts of the Video that have been changed by a filter or effect.....

Cheers