cut clips in cineform, virtual dub or vegas 9?

[William Boehm]

i have transferred 70 hdv tapes from a canon xha1 with neoscene 4 to cineform avi files, using the high quality setting. question is do i cut the clips in cineform and not loose any IQ? I realize that cineform is I-frame and you can make cuts anywhere, but is it true you still have losses upon export (both compression lossess and colorspace losses, even tho considered minimal and neglible for most people.

or should i cut footage in virtrualDub with NO quality loss from that cineform generation if I use "direct stream copy mode".

i am trying to edit with the least loss from the original cineform codec...finishing everything in vegas 9e. thanks in advance. bill

[David Newman]

Vegas supports smart render, lossless move of compressed sample from input to output file. VirtualDub can do the same. The multi-generation quality is so good, you need not worry.

[William Boehm]

david...again i am a beginner just having immersed myself into this the past two weeks. by cutting in virtual dub Video=>direct stream copy , Audio=>direct stream copy, technically it's not "cutting" i was told, it's really stream copying clips into another cineform AVI (where my original Cineform file is unaltered). Is it true then that no quality loss occurs when done this way because cineform is all I-frame (Everything is a keyframe). i read from you that cineform is within YUV colorspace (YUY2 4:2:2). How does Vegas do this? in smart render..what do i need to check in order to take out sections of the clip without changing this color space.

I understand that deshaking some of my clips in the filter in vdub will operate in RGB colorspace. Colorspace conversions cause slight quality loss. Isnt this also true with any edits i make with the cineform avi's in Vegas 9? i hope i am making sense..just want to have the best quality i can get, but that quality may not be noticeable unless pixel peeping.

I was also informed that if I export uncompressed RGB, instead of cineform 4:2:2 , you will incur less loss (because 1 less colorspace conversion, and no compression loss) . I need a pretty simple explanation, just trying to get good and rare marine wildlife footage into a good form. thanks again. bill

[David Newman]

You will be fine using CineForm, colorspace conversions or not. I've done 100 generation in Vegas, forcing a render and colorspace converison without significant image degrading -- and you are only talking one generation. Both Virtual and Vegas support "Direct stream copy" work, but not when apply a deshake. If you are really concerned you should be using NeoHD or Neo4K. NeoHD gives you FirstLight a renderless, non-destructive color correction and reframing engine. Neo4K adds 4:4:4 RGB compression.