V6c: HDV .m2t import is not robust

john-beale wrote on 11/21/2005, 9:49 AM
My Inspiron 9300 notebook running Vegas 6.0c normally handles 1080i .M2T files from my FX1 with no trouble, I have imported a number of hour-long captures from tape and 2-hour live captures. Yesterday, one capture from tape had a few corrupt frames at the very beginning. Vegas captured it but hung at the very end. I closed Vegas and checked that the file was present on the disk- it was. Nero ShowTime could play it immediately, although the first few frames were blocky, there was no other issue. Vegas, however, refuses to import the file, saying (after literally 20 minutes of disk access):

Warning: An error occurred while opening one or more files.
The reason for the error could not be determined.

Details:
File C:\Documents and Settings\John\My Documents\My Videos\RichardTracey.m2t could not be opened.

This is not really satisfactory. I'd like to ask that the Vegas engineers reconsider their file import routines to make them more robust. Occasional tape readback errors can happen anytime and programmers need to plan for it. If Nero can access and play the entire file, there's no excuse for Vegas to give up on it.

Comments

JJKizak wrote on 11/21/2005, 4:40 PM
Wow. You sound like you want a Western Electric/Bell Labs designed software that anticipates and corrects defective code and malfunctioning equipment for Taiwan prices. You might try Unix. It will not happen so just clean your tape heads like everybody else. You should be happy that Vegas will not import a defective file.

JJK
john-beale wrote on 11/21/2005, 6:56 PM
When the program spends 20 minutes, yes 20 minutes, locked to user input while accessing the hard drive, only to conclude "an unspecified error occurred" it seems to me like a bug in the program. Especially when another application can display the given video without locking up. Graceful error handling is not some kind of exotic luxury, it's just good programming practice.
JJKizak wrote on 11/22/2005, 6:10 AM
I'm sorry I was so rude, it must have been the full of the moon.

JJK
Laurence wrote on 11/22/2005, 6:23 AM
One thing you might want to do is go to womble.com and download the trial versions of Mpeg Wizard and Mpeg VCR. These programs can smartrender the M2T mpeg stream directly. Anyway, with Mpeg VCR you could try cutting a little off the front, saving the result, then loading that in Vegas. I'll bet you it works just great.
john-beale wrote on 11/26/2005, 6:38 PM
I fixed my original problem by re-importing the entire hour-long tape but starting a few seconds after the very beginning; this worked ok.

Yesterday the same thing happened again on a different tape and I tried just what you said. I downloaded the "Womble" MPEG Video Wizard, trimmed off the first three seconds and re-exported to a new file. Vegas 6c was able to read the new clip with no problem, just as you suggested. Thanks for the tip!

I still wish it worked right the first time without the runaround, though. I wonder if I shelled out $200 for the CineForm ConnectHD with the standalone M2T import/export, it would fix this issue.
Spot|DSE wrote on 11/26/2005, 7:07 PM
CineForm is VERY good at dealing with corrupted headers. It's been my saving grace on a couple of occasions. QuickRec can really mess you up sometimes. Don't use it unless you need it.
Laurence wrote on 11/26/2005, 7:23 PM
Obviously you're not going to use everything you shoot. The Womble MPEG VCR or MPEG Edit are really good for separating the good footage from the bad. MPEG VCR in particular is great for this. You can load the single large M2T clip into MPEG VCR, then select the first bit you want, go to save, but instead of saving it, add it to a batch file. Go back and select the second bit you're going to use, add it to the batch, the third, etc.

When you're done, run the batch file and you'll get a number of small M2T clips consisting of just the stuff you really want. If you want to recover some space you can delete the original large M2T file. The quality is the same in the split clips. These smaller clips are also easy to back up on DVD-R. From that point, you can load these clips onto the Vegas time line, use the free "events to regions" and "batch render" script to render these sections to Cineform codec and you're ready to go!
john-beale wrote on 11/26/2005, 9:02 PM
Thanks for the tips. If I was shooting re-takes I would definitely trim it down first. Currently I'm doing two-camera shoots of theater productions, and every minute might potentially be used, so to avoid re-syncing footage I just convert the whole thing at once. I've got enough disc space to do it this way, although it does take a fair amount of conversion time to generate the HDV Intermediates.
MH_Stevens wrote on 11/27/2005, 11:32 AM
Capturing footage as one huge file is always a strain on any processing system. Capture using scene detection where each take is a separate file and I don't think this would have been a problem as you would just discard the first bad take.


johnmeyer wrote on 11/27/2005, 11:36 AM
When you're done, run the batch file and you'll get a number of small M2T clips consisting of just the stuff you really want.

Laurence, thanks for the tip! I've been trying to figure out how to do that in Womble. I knew it must be able to export the clips as separate files, but didn't see the way to do it. This will be a big time saver.
johnmeyer wrote on 12/2/2005, 6:28 PM
I tried Launrence's tip, but couldn't get the individual clips into the batch file export. It still wants to take all the clips and export as one single file.

[Edit] Ah, I finally found the elusive "Trim Manager." I was trying to drop the files into the batch section of the Export Manager. Confusing (to me).
john-beale wrote on 12/3/2005, 9:34 AM
> Capture using scene detection where each take is a separate file and I don't think this would have been a problem.

Thanks for that info, I will have to try the scene detection- I didn't think it would work for me because the camera was rolling the full hour long- it's live theater so there was only one take, and the lighting changes were gradual, not like hard cuts.