I want to crop a video file that is already burned to CD-R in order to make a 4:3 TV version. Since I have a 16:9 bigscreen the black bars resulting from Tmpgencs "keep aspect ratio" setting are perfectly fine (much better than using my set's 4:3 mode). If I can access the mpeg2 file in the folder created by Nero during the CD-R burn shouldn't it be possible to crop the image and make a 4:3 version without any re-encoding?