Vegas HDVSplit & Womble

Laurence wrote on 7/26/2007, 10:10 PM
OK, so I'm working on a new project and I've got about 12 tapes of HDV, so I want to use native m2t editing rather than Cineform so the project won't be ungodly large. I have figured out the following for most efficient m2t editing. Please feel free to correct or add more as you see fit.

1/ Use the Vegas capture rather than HDVSplit. HDVSplit is a wonderful program, but the m2t clips it generates don't play nearly as efficiently on the Vegas timeline.

2/ Don't edit the clips with Womble MPEG Edit or MPEG VCR unless you are doing this to fix a corrupt capture. As soon as Womble touches the m2t clips, they don't play back as efficiently as they did after the Vegas m2t capture.

3/ Quite often (at least once per tape), the Vegas m2t capture will give you a clip that crashes Vegas if you put it on the timeline. When this happens, loading the offending clip into MPEG VCR or MPEG Edit and resaving it will usually make it work again. When you do this, be aware that it will not play back as efficiently on the Vegas timeline, but that is better than crashing Vegas.

4/ Never capture from Vegas without using the split clips option. The Vegas capture will split the clip several times anyway and when it does, it will usually be during an important section that you would rather leave intact. Worse than this, it is extremely likely that somewhere within one of these large clips will be an error that will crash Vegas as it is generating the audio waveform data.

If I follow these rules, I can edit native m2t video at preview resolution with no dropped frames (except on the Womble fixes) at about 70% CPU on my P4 2.8 laptop. Not too bad I would say.

Comments

blink3times wrote on 7/27/2007, 3:01 AM
Are you using 7e or 7d?
NickHope wrote on 7/27/2007, 4:37 AM
Laurence, as I'm sure you know, the performance on the timeline depends largely on whether the m2t clip is decoded by the Main Concept codec or the new Sony codec that was introduced in Vegas 7 (which codec is used can be checked by examining the file properties from the context menu in the Vegas explorer window, as discussed in previous threads).

Quite exactly what makes an m2t file worthy of being processed by the Sony codec is a mystery but I have already been in discussion with the engineers at Womble about a bug with their "GOP Trim" feature and I'm also asking them to see if their output m2t files can be made compatible with the Sony codec.

> HDVSplit is a wonderful program, but the m2t clips it generates don't play nearly as efficiently on the Vegas timeline.

I have found that the majority of the clips I capture with HDVSplit are in fact processed in Vegas 7 by the Sony codec and therefore play efficiently on the timeline. The ones that don't perform well (because they are handled by the Main Concept codec) are either the first one captured off a tape or those adjacent to a break in timecode caused by me having Quick Rec ON on my Sony Z1.
mbryant wrote on 7/27/2007, 5:12 AM
Laurence, I agree.... I've been capturing with Vegas (7e) and editing natively. I don't think II've ever had a clip which causes a crash, but I do get the dreaded 2 black frames bug regularly.

Generally the clips behave fine for me on my 2.0 Ghz core duo laptop. On my latest project I had 11 tapes; for some reason one of the tapes was a real pig to edit. On all the other tapes I could preview at full rate, on this one tape only about 2 fps. No idea why or what was different. I did use scene splitting but it was recording of a live show so was one big clip (but so were the other tapes). Wierd.
Mark
Laurence wrote on 7/27/2007, 10:17 AM
"Are you using 7e or 7d?"

I am using 7e.
blink3times wrote on 7/27/2007, 4:12 PM
Don't know about womble, but I had NOTHING but trouble with HDVsplit and 7e. It seemed that every other clip that the scrubber touched would crash Vegas... and they rendering was terrible!!! endless crashes. I had the same crash problem with 7e on both vista and xp.

When I rolled back to 7d, the problems COMPLETELY disappeared.
riredale wrote on 7/27/2007, 9:57 PM
Wouldn't know about 7e, but am happy as a clam with 7d and HDVSplit.77b.
Laurence wrote on 7/28/2007, 10:12 AM
The thing about 7e is that when it's not crashing, it is more efficient with both m2t and Cineform. With 7e I can get great previewing performance with m2t clips on my P4 2.8 laptop if they are captured with Vegas. The crashing is related to something that happens to captured clips occasionally upon capture. I can fix it by resaving them with Womble MPEG VCR. When I do this, the m2t preview performance on these resaved clips drops down to what it would be all the time on Vegas 7d. If I had a faster PC, I'd probably drop back to 7d as well, but as long as I resave the offending clips, my overall performance is better in 7e.
4eyes wrote on 7/28/2007, 2:25 PM
Laurence,
4/ Never capture from Vegas without using the split clips option. The Vegas capture will split the clip several times anyway and when it does, it will usually be during an important section that you would rather leave intact. Worse than this, it is extremely likely that somewhere within one of these large clips will be an error that will crash Vegas as it is generating the audio waveform data. Actually, to me this explains the crashing and splitting of the files, if you cannot capture a continuous stream without the program splitting the videos it's usually tape corruption. During capture, if an error is introduced in the stream then the program processes that file and starts a new one. When this does occur you can expect a crash and the end of the file where the program closed the stream. Stop any audio/thumbnail waveforms being generated when loading them into the timeline. If you then can get it into the timeline seek about 20frames from the end and "S" split, then delete the end corruption. Then render a new .m2t file.

If your not using good HDV certified tapes then at least try one. Record on it and then try to capture the complete tape. If you can capture the whole tape then you have your answer.
I had the exact same issues as you, cleaned the heads, threw the cheaper tapes away and started using better Sony brand tapes including the HDV Certified ones. I have not had any if these previous problems after cleaning the heads and using good Sony tapes.