Lossless video editing on Linux?
If it is mpeg2 you can use gopchop
gopchop - Fast, lossless cuts-only editor for MPEG2 video files
I think avidemux can do this as well
avidemux - a free video editor - GTK version
basically you would make your cuts and then save the output file and tell it to 'copy' rather than re-encode anything...
from the command line you can use mencoder or ffmpeg the same way. Specify the start and end times, but use 'copy' for the codecs.. something like..
ffmpeg -vcodec copy -acodec copy -ss xxx -t xxx ...