is there a m2v loseless cutting tool?
 

i have demux-ed a dvd into its m2v & ac3 components.

i want to trim/cut off the starting 1 min.

i have tmpgenc mpeg editor which can do the cutting.
but i suspect this will re-encode the m2v and compromise the original quality of the video.

ok, that is not the end of the world.

but is there an app to loselessly cut the m2v file?

thanks.

Yes. Try Womble MPEG Video Wizard.

The only caveat is that Womble saves to a program stream (MPEG-PS), not elementary streams. So you'll be saving to a .mpg file, and you'll have to re-demux in something like BatchDemux or TMPGEnc Plus (via MPEG Tools). Most MPEG editors are consumer apps, and elementary streams are not the typical input sources.

There's quite a few ways to do this, and quite a few programs, but I think you'll find Womble the most reliable. If nothing else, it tends to strip out non-video junk from streams. Other editors can leave junk, or even be confused by it. I remember wasting many hours on such nonsense years ago, before Womble software existed.

For free options, MPEG Streamclip may also be an option, for both Windows and Mac OS X.