m2v bytes size indicate same file?

[efc1978]

Hi,

I'm working on making a concert DVD by taking the best 'video' source and best 'audio' source and muxing as 1 new DVD.
I have a bunch of unknown sources and generations on DVD, some of which have been edited in various ways, so I have to compare to see what looks/sounds the best...
I have used PGC Demux to split the audio/video from 2 sources of the concert which I thought were possibly different edits eg. one source of the concert was split over 2 individual 4.5GB DVD's, the other source was combined onto 1 single dual layer DVD 8.5GB.
When I compared the m2v files I found that right clicking properties shows the bytes size is exactly the same when comparing the first single DVD to part 1 of the dual layer DVD, and the same for the second single DVD when compared to part 2 of the dual layer DVD.
Does this mean that the m2v's are exactly the same? - Seems like a stupid question I know, the reason I ask is for example I know when working with audio .WAV files if the file length is exactly the same as another .WAV file the bytes size of the 2 will be just a few bytes different even if the music is completely different...
So for m2v. does same bytes size indicate the same length (but maybe different quality/content)?, or does it indicate the whole of the 2 files are exactly the same?
Thanks

[El Heggunte]

Nope, exactly-the-same filesize has nothing to do with exactly-the-same content.
You can check easily by running in a command prompt:

fc /b file1.m2v file2.m2v

— assuming that file1 and file 2 are in the same directory.

If file1 = file2, then fc will say "no differences encountered". BUT if fc shows an "endless" sequence of hexadecimal addresses, then you may already stop it by pressing CTRL + C or CTRL +PauseBreak, because file1 is definitely different from file2.

[efc1978]

Thanks, but I'm having some type of problem getting the command / file paths correct, can't get it to work, I'm getting things like "no such file/folder".
If I use Traders Little Helper to create an MD5 of both m2v's will matching MD5's mean the 2 files have identical content/quality and are exactly the same?
Thanks

[videobruger]

I'm having some type of problem getting the command / file paths correct, can't get it to work

If your path/filename contains spaces or such

fc /b "file1.m2v" "file2.m2v"

will matching MD5's mean the 2 files have identical content/quality and are exactly the same?

Yes.

[efc1978]

It's all working now.
Thanks guys for your help.