DVD Architect 5 BluRay Blus

[Dave Edwards]

Hi Michel:

You may well be right,- I was so happy at having a viable disk that I may not have looked at it critically enough.

I think we may have to wait for DVDA version “C”?

[Dave Haynie]

You should look at your whole toolchain to decide if this is even an issue.

For example, if you shoot in HDV, and render a 25Mb/s MPEG-2 video stream from that, you’re pretty much running at the full quality of your camcorder. Going to AVC might give you the same quality at lower bitrates, but it’s not going to improve quality.

In theory, AVC has about twice the encoding efficiency of MPEG-2. That means that an AVC bitstream at 12.5Mb/s should deliver the same apparent quality as an MPEG-2 bitstream at 25Mb/s.

This is not always the case. For one, MPEG-2 is a very mature technology. Back in the mid-90s, there were drastically different qualities from different MPEG-2 encoders.. these days, they pretty much all do a good job. AVC is still kind of in development.

You know this, if you’ve played with AVCHD and MPEG-4 camcorders. It wasn’t really until this year that AVC camcorders routinely produced better quality video than HDV. Most of the consumer media camcorders (HDD, flash, DVD/BD) went to AVC to lower the storage demands. However, AVC is complex enough that, doing the encoding in realtime on a low powered camcorder, they didn’t even really match MPEG-2 quality. The evolution included both improvements to the encoders and upping the bitrate… all the way to 24Mb/s on consumer models.

With that said, given all the time it wants, an AVC encode on a PC should be good. It’s still algorithm dependent (eg, it’ll probably be better next year, if work is still being done), but taking the time element out helps. On Vegas, you have issues, though. Sony’s encoder is CBR-only, and limited to 16Mb/s or so. MainConcept’s can go to 20Mb/s and supports variable bitrate, but it wasn’t initially the one recommended for Blu-Ray, but rather for device stuff. I don’t know way.. but clearly, things are still in flux.

Of course, if you’re starting with an AVC source, and SmartRendering works, that’s a big advantage… SmartRendering means you’re not re-encoding, so quality will be optimized. I haven’t managed to get AVC to SmartRender at all, but then again, I’ve mainly been shooting beyond the Sony/MainConcept limits on my AVC stuff (1080/60p @ 24Mb/s).

The bottom line: unless you need the space on a BD, you probably get no advantage out of AVC. There may be disadvantges, maybe not.. other than the 3x encoding time.

-Dave

[Lou Van wijhe]

Hi Dave,

This “Video Buffer Underflows” issue has been confirmed by Sony Creative Software to be a bug. It may be a bug in Vegas Pro 9 as it never happened to me in Pro 8.

Further info here: https://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=22&MessageID=679100

Lou

[Michel Van nistelrooij]

Thanks Lou for your answer.
I’m glad to hear that Sony knows the error now.

I keep an eye on that forum thread you gave me!
Now we wait indeed for the “C” version ……..

[Dave Edwards]

Thanks, Lou: for the moment I’m using MPEG2 – have you seen Dave Hayne’s comprehensive post.. my camera takes AVHCD so it seems logical to stay with the format through to final disk..

[Michel Van nistelrooij]

Hello Dave,

My source is also AVCHD.I did several tests but my opinion is that when i use AVC blu-ray it is sharper/nicer then when i re-encode to mpeg. Not much but it is sharper.
And offcourse the new smart render. When i insert my source, and render it to “Sony AVC” as AVCHD file then it does smart render( if you don’t change something offcourse).

So that are 2 nice things. But offcourse this is my opinion.

I just saw Vegas Pro 9C is OUT!! I’m not at home for the next 2 days!! Can someone test if the bug is solved?? i’m dying to know!!

[Michel Van nistelrooij]

Hello Dave,

My source is also AVCHD.I did several tests but my opinion is that when i use AVC blu-ray it is sharper/nicer then when i re-encode to mpeg. Not much but it is sharper.
And offcourse the new smart render. When i insert my source, and render it to “Sony AVC” as AVCHD file then it does smart render( if you don’t change something offcourse).

So that are 2 nice things. But offcourse this is my opinion.

I just saw Vegas Pro 9C is OUT!! I’m not at home for the next 2 days!! Can someone test if the bug is solved?? i’m dying to know!!

[Lou Van wijhe]

This buffer underflow bug has indeed been fixed in Vegas Pro 9.0c!

Lou

[Dave Edwards]

Hi All:

I too can confirm that version “C” has corrected the bug! Excellent!