killer spot in m2t file

ushere wrote on 5/14/2008, 3:36 AM
just went to work on a backed up copy of an m2t file (50mins long) from hd, and there's a spot at 38:16:16 that literally crashes vegas with the 'unexpected error' error and / or simply closes vegas (8d) completely.

in frustration, i cut 2 secs either side of what appears the offending frame, deleted the 4 secs and now it plays. unfortunately, this was the final mixed version and i now have an audio jump. nothing that can't be repaired the long way....

has anyone else experienced this? is there anyway of salvaging the file?

it plays fine in vlc, power dvd, etc,.

advice, suggestions most welcome.

leslie

Comments

Laurence wrote on 5/14/2008, 5:07 AM
This is exactly the sort of error that http://www.videohelp.com/tools/MPEG2RepairMpeg2Repair[/link] is designed to fix. Be aware that the "fix" works partially by changing the header and making Vegas play the mpeg2 with a different playback codec. Part of the why it will now work is that it is being played back by a codec with more robust (but slower) error correction.
ushere wrote on 5/14/2008, 7:04 AM
many thanks laurence, it worked perfectly.

funnily enough i've had mpeg2repair on my pc for about 2 > 3 months (i think you recommended it in another thread), and used it successfully on a minor tape problem - certainly not one that gave me such angst as this one.

strangely there was no errors recorded in the error log, but i'm not going to worry about that....

is there anything i should be aware of when using this file in vegas, such as ptt?

again many thanks for your speedy response,

leslie
Laurence wrote on 5/14/2008, 7:52 AM
I can't stress this enough. Errors like this are introduced during tape capture and often not noticed until they give you problems later on.

The biggest single thing that I do to avoid this is to turn off the background virus protection before I start capturing with HDV Split.

Other things I do are to turn off the HDV Split video preview window, turn off any other background processes I can spot, and capture HDV video after a fresh computer reboot. Turning off the virus protection is the most important one though.
ushere wrote on 5/14/2008, 4:53 PM
just as passing observations regard my problem....

a. i always capture with sony's app. ingesting via a m15 vtr. so far i've never had any other problems that the occasional splitting of what should have been a continuous capture. on a couple of occasions this 'splitting' has lost me a few frames, which required a recapture. the split never occurs twice in the same place.

b. no virus protect on capture. that said, i run avast, and have occasionally forgotten to turn it off whilst capturing. however, the above 'splits' occurred in both states, ie, virus on and off.

c. the original file i was referring to was an edited version that somehow developed this 'killer' frame after a few weeks of not being played at all. however, i might have defragged the hard drive during that time (my memory isn't what it er....)

all that to one side, your advice worked, and i am very grateful for your prompt response,

many thanks again,

leslie


farss wrote on 5/14/2008, 5:11 PM
Isn't this though from a file that was rendered out from Vegas, not captured from tape?
You didn't by any chances update V8 in the interim?

Bob.
Laurence wrote on 5/14/2008, 9:02 PM
Again, the part of the video that crashes could have had an error that was introduced during capture, then smart-rendered into the final piece. If you were running 7d or earlier, you would never even notice this error because of the more robust error correction in those versions. Then if you updated to 7e, 8a or 8b and tried to play or render from this file, the error would suddenly begin crashing your project. This doesn't mean however that that error wasn't there from the beginning.
ushere wrote on 5/15/2008, 2:53 AM
the video was:

v1p > cap with sony app in v8b > heavily edited > rendered (smart) to new m2t.

this new m2t was the base for various outputs - dvd, mp4, etc.,

problem only arose when i loaded it back into vegas to do a short version. no upgrades, no nothing in between re software / hardware.

laurence's advice has got it playing back once again on the timeline - and i've just read his new posting, so i'll simply try it on the nasty bit and report in that thread....

thanks gents...