Choosing the right render template

Yep wrote on 8/9/2014, 11:06 PM
I am editing videos in Vegas Pro 13 that will ultimately be burned to Bluray in DVD Architect Pro 6 and viewed on HD TV. As a relative beginner I find choosing a render template very confusing - there are just so many options. In particular I'm confused about how bitrates affect the finished product. I generally use Main Concept MPEG-2, as Main Concept AVC takes a huge amount of time to complete renders.

As a general principle would I be correct in thinking that if the original footage was shot at say 10Mbps, there is no point in rendering at full Bluray bitrates of 25Mbps? Obviously I'm trying to achieve the best quality possible while taking up the least amount of space on the Bluray disc.

Thanks for your help.

Comments

PeterDuke wrote on 8/9/2014, 11:36 PM
The main requirement is that you choose a template that is compatible with the Blu-ray spec, otherwise DVDA will re-render it.

With that constraint, choose a template that is closest to your source. For the same encoder, a lower bit rate will lower quality, but a higher bit rate will not increase quality, although it may prevent some loss of quality resulting from re-encoding. Such a benefit is small and a very high re-encoding rate would produce large files with no significant benefit.

If you are able to smart render, so much the better, but this is often not possible. For instance I use Vegas 9c to smart render AVCHD for Blu-ray, but it is not fully reliable, and is not available with later versions of Vegas.

As always, don't be afraid to experiment and critically examine your own results. You will soon learn what works best for your situation.
Yep wrote on 8/13/2014, 11:14 PM
Thanks for that - it has made things a little bit clearer. I do try to do short test clips to compare results - but sometimes I find it difficult to tell if there is a significant difference. So I'm trying to get some understanding of the principles involved to put some focus on what I'm doing - rather than taking blind shots at it. It's always better to start from a point of understanding.

A couple of questions if you don't mind.

1. When you say "a template compatible with Blu-ray spec", am I correct in thinking that only the predefined templates with "Blu-ray" in their name are Blu-ray compatible?
2. If I selected say "Blu-ray 1920x1080-24p, 25Mbps video stream" and customized it so that the bitrate was 10Mbps - would that still be Blu-ray compatible?
3. I have been using .w64 for audio, should I be using AC3 instead?

Sorry if these querys seem very basic - but I'm really at the very bottom of the learning curve.
Kimberly wrote on 8/14/2014, 12:42 AM
My advice is to start with the end in mind.

Launch DVD-A and set-up a Blu-ray project. You have a couple choices on frame rate and screen size. Ideally you should choose the one that is closest to your native footage, but you can choose any you wish from the available choices.

Now go to the Help in DVD-A and search on "Recompression, avoiding" to find the video and audio render specifications you need to create DVD-A compliant files in Vegas Pro.

Now that you know this, go back to Vegas and set-up your project parameters accordingly. When you render, choose a Render Template with an equals ( = ) sign next to it. Those are the templates that match your project parameters, which in turn match your project properties in DVD-A.

Buy a BD R/W so you can experiment with burning. That way you won't waste a bunch of disks, BDs are cheaper than they were in the past, but they still ain't cheap.

Good luck : )

Kimberly
john_dennis wrote on 8/14/2014, 1:35 AM
"[I]As a general principle would I be correct in thinking that if the original footage was shot at say 10Mbps, there is no point in rendering at full Bluray bitrates of 25Mbps?[/I]"

Would you indulge us by showing us what your source bit rate, pixel dimensions, pixel aspect ratio and progressive and/or interlaced parameters actually are?

Don't guess. Download and install Mediainfo, cut and post the actual results measurements from the text view of that application.

Do you have video from mixed sources as from different cameras or other sources? If so, include the Mediainfo results for all the sources.

If you want to learn the underlying rationale for choosing one template over the other we could help you better with more detailed information.
John222 wrote on 8/14/2014, 7:19 AM
Suppose the footage is 1080 - 60P, what would the BD recommended template be?
john_dennis wrote on 8/14/2014, 8:51 AM
I've found this web page informative about Blu-ray.

"[I]1. When you say "a template compatible with Blu-ray spec", am I correct in thinking that only the predefined templates with "Blu-ray" in their name are Blu-ray compatible?[/I]"

Not at all. Some template customizations will pass through DVD Architect like a hot knife through butter. Some acceptable Blu-ray templates are not offered by Vegas Pro, but can be built to match the acceptable specs as shown on the link I posted above. A famous example is 1280x720-59.97 progressive.

"[I]2. If I selected say "Blu-ray 1920x1080-24p, 25Mbps video stream" and customized it so that the bitrate was 10Mbps - would that still be Blu-ray compatible?[/I]"

Yes. Rendering higher than the maximum bit rates is more often the problem. The quality will suffer with lower bit rates but it may be acceptable to you.

"[I]3. I have been using .w64 for audio, should I be using AC3 instead?[/I]"

With Blu-ray you can have both on the same disk. Render the separate audio types from Vegas Pro then add tracks in DVD Architect.

"[I]Sorry if these querys seem very basic - but I'm really at the very bottom of the learning curve.[/I]"

We're all at the bottom of some learning curve. The trick is not to go down the other side of the ones of which you've reached the top.
john_dennis wrote on 8/14/2014, 9:00 AM
"[I]Suppose the footage is 1080 - 60P, what would the BD recommended template be?[/I]"

Depending on the action in the video, I might choose 1280x720-60p. I'm sure others will chime in on getting 30p into a 60i template. There is not an approved 1080-60p Blu-ray frame rate. You're going to lose something.
Yep wrote on 8/14/2014, 9:20 AM
Thanks for all the replies.

I found Kimberly's advice particularly helpful. I've read up on the recompression notes in DVDA Help, and the mist is slowly begining to clear. I'm starting to see the logic behind the system.

I don't really have a problem with posting specs for original media - but I'm not sure that it would be helpful. I have footage from a range of sources, and they vary considerably both in their specs and codecs. Because of that I really want to focus on knowing how to make the right decisions for any media that I might come across, rather than drilling down on one particular piece of media. For me the most important aspect of my original question is to develop a good technical understanding of how things work.

If I get really stuck I'll post specs. For the moment I'm going to beaver away on a couple of projects and try to develop my knowledge.

Sincere thanks to everyone. I really do appreciate your efforts to educate me. ;)