Vegas M2T audio peak issue... a fix!
 

In prior versions I had the problem of peaks flatlining or missing on some clips and the audio would or would not be audible in these regions. I've seen this issue in several forums... well, On version 8.0c, I never really saw this issue until yesterday! I tried and tried all kinds of things (I won't list them all here, but trust me... almost everything from trying to export audio from other programs and incorporate to "fix it all" programs, etc.)

Sony needs to look into this program I'm about to tell you so they could create a feature like this in their next version. Anyways, here it is:

VideoReDo MPEG Video Editing Software

Download the trial (I'm gonna buy it just to have for when I need it... it costs $50) Register for the trial key!!!

Open Video.

On files of type, choose "All files".

Select your faulty m2t file.

Go to tools and select "Quick Stream Fix"

Choose your output file name, and CHANGE THE EXTENTION TO M2T.

Open that file in Vegas. ALL IS FIXED!

It took 11 minutes to do a 1 hour 5 minute clip (it would go faster if the program would use all 4 cores, but it won't) and it said it found 5 Video resync frames removed.... whatever that means.

Its a corny looking program, but it works! That's all I care about!

I have not had this issue and I am not quite sure I understand what you are describing but you sound very excited about this solution. If I do encounter it, I want to understand better what it is fixing, since I am moving to HDV exclusively. Does it just boost the missing audio or is it more of a balancing result or something else? Thanks for sharing your find and I look forward to learning more about this problem and fix. Thanks!

Bryan, its an issue with some M2T files which are HDV MPEGs. Its been since version 7 that I've seen anything serious (I think since 7) until yesterday. What happens is, due to some kind of glitch in the capture process or vegas' reader, when the audio peaks are built, it flatlines in places. Sometimes, you can hear the audio, but see no waveform and sometimes you don't hear the audio. Its freaky. This process is not boosting the audio. It is correcting whatever is amiss so Vegas will play with it nicely like it is supposed to do. I even tried recapturing the tapes and it would still do it... sometimes in same place, but not always. There has been posts about this several places and I just wanted to post my fix that I found. Hopefully, you won't encounter this issue...... good luck on your move to HDV! Oh, one thing I'm thinking about doing is just using Cineform to capture with their codec... it ends up resampling the image to 4:2:2 vs. HDV's 4:2:0. File sizes are larger, but I have close to 10 TB of space so I'm not worried about that... also, hopefully this issue won't rear its ugly head again when I start doing that because I won't be messing with HDV's 15 GOP "feature" which I feel is part of this problem.

Jerome- thank you so much for clarifying that for me, i was correct in my assumption that i was missing something. Your explanation makes it much more clear for me now and I will watch for it. I have been shooting HDV mixed with DVCAM since last year and with the new Z5U/FX1000 i am looking to retire my PD170 and go to HDV only even when delivery is DVD, so I really appreciate your find. Thanks for sharing!

The problem you described happened to me for the first time last month. I nearly fainted when the audio was missing (at least two minutes' worth) and then I was left scratching my head when I recaptured that portion and the audio was there.

Thanks for helping me understand the problem a bit better, as well, and for offering a couple of fixes.

Nice find, Jerome, but I'm convinced this has more to do with audio card/drivers and Vegas code than GOP, as I've seen it with DV as well on rare occasion. Flat-lined audio with sound actually being present. Sometimes F5 works (rebuild the peaks) and a lot of the time it doesn't.
either way, sounds like you've found a nice solution to the issue. Thanks for sharing!

u can do the same fix by running your native m2t thru Tmpgenc4. Select m2t as the output, therefore no re-rendering takes place.

TMPGenc4 is $50 more too. VideoRedo didn't render again, it just scanned the file and removed the bad frames (as it says). I know it didn't render again because it couldn't render that fast on only 1 core at 13 minutes or so for a 1 hour video.

Good to know something else works too.

NOTHING has changed on this PC (or the other one as I tried it on the other computer too) so I doubt its a driver issue. I tried rebuilding peaks--even 8 bit peaks.

Ahh well, it works now.....

yes, but...
1-TmpGenc is acknowledged to be one of the best transcoders on the market
2-Tmpgenc is WAY more capable of transcoding than VideoRedo
3-Most people already have Tmpgenc, so why buy an app to do what you already can do with Tmpgenc

I just remember several people having this issue on several forums and there wasn't ever anything posted (in my searches at least) on a viable fix and I posted what I found that worked for me. I don't care what program works... heck, I wish this issue never existed.

Jerome, All I can say is thanks for posting your results on how you solved a problem.

I use VideoReDo all the time for trimming MPEG2 files and removing commercials from ATSC Transport Streams. It works flawlessly. I also occasionally use the "Quick Stream Fix" but I have a freeware program that performs the same function and will generate a detailed log of what it found and what it fixed. It's called "MPEG2REPAIR" and is available here:

MPEG2Repair

TMPGENC4 = $99, VideoReDo = $50, MPEG2REPAIR = FREE

I ran MPEG2Repair and it did not fix the problem.

I'm not precisely sure why you want to import native m2t files. If, indeed, all you're doing is cuts, then I can understand, as you're saving yourself an extra step of rendering. However, if you're doing any re-rendering, i.e. color correction, FX, or transitions, I would encourage you to transcode your footage to an intra-frame compression codec prior to doing so. M2t format is really not re-render friendly, despite the processing power of modern cpu's. You will incur image degradation with every re-generation.