Maintain High Audio Quality on DVDs

[snapware]

I worked hard on some audio for the DVD, however i notice when i make the DVD with Sony Architect it always wants to compress my audio, is there a way i can maintain high audio quality on my video file?

[Cornucopia]

In you DVDA project properties, set Audio to "PCM" (or "LPCM" if it says that). You'll have to adjust the video bitrate accordingly so everything will still be within spec.

Scott

[guns1inger]

It will always want to compress the audio if the project properties do not match the format of the audio, regardless of what it is.

Be aware that PCM will eat a large amount of space, and depending on the length of the video, may cause you to have to compromise video quality. You might also want to test AC3 at 384 or 448kbps if space is an issue.

[snapware]

in Sony DVD Architect 3, how can i adjust my AC-3 Stereo bitrate? It says Estimated size is 81.2 mb for the audio, which is low, i want to have higher quality audio but i don't see a way to change the settings. I would like equivalent to 192k mp3, at least

[lordsmurf]

Compression is not a bad thing. It all depends on what you do.

For AC3 stereo, use 256k bitrate. I would not go any lower, especially not with homemade recordings. At that bitrate, the filesize is about 40MB per 22 minutes.

I don't have v3 of Architect, so not sure what to say there.

[yoda313]

For AC3 stereo, use 256k bitrate. I would not go any lower, especially not with homemade recordings

Actually my liteon settop recorder and my fusion hdtv default to 224 for audio. It still sounds pretty good.

But I would agree that 256 should be a "minimum".

[snapware]

i really don't think DVDA 3.0 lets u change the bitrate on the AC3 settings

[guns1inger]

Personally, I wouldn't let DVD Architect make any of these decisions for you. You should sit down with your bitrate calculator, work out how much you have to play with, and encode from Vegas at correct bitrates. Import these assets into DVD Architect. This way you maintain all control and make all the decisions.

[Cornucopia]

DVDA doesn'tforce you to recompress, or automatically recompress for you, unless you set it that way AND your material is too long or non-compliant.
It will flag the material so that you know which needs to be reworked, and it does have a "default" that it will try to recompress to IF you tell it to recompress (FIT TO DISC).
That default is in the project properties dialog box and allows you to set the video bitrate and the audio stream type and bitrate--it has fixed bitrate expectations for 2.0AC3, 5.1AC3, 2.0 MP2, and 2.0 PCM (which you can ignore if they don't match your requirements).

I do recommend that you plan out your bitbudget FIRST, using a good bitrate calc and using conservative available space estimates.

There is nothing wrong with compressed audio, in the right circumstances and using the right settings. 256kbps would probably be plenty for you with 2.0AC3. I would put 192kbps AC3 at the equivalent of mp3's 224kbps, so 256kbps would be similar to ~320kbps mp3. What kind of material do you have? Concert footage or Music Video? Unless you have high requirments like that, AC3 is probably a better choice than PCM.

Scott

[snapware]

yes, i have high audio requirements because it's music videos, so i need to maintain the quality, i'm gonna take a look, thanks

[snapware]

When i encode the video in Vegas using the Mainconcept mpg2 encoder, is that saving the audio stream as ac3? it doesn't mention the type anyplace, but it gives me an option to change bitrates

[guns1inger]

If you don't use the batch render script, you have to render the audio to AC3 seperately.

[snapware]

i just don't want to lose any audio quality from the time i import the .wav file into vegas, to i burn the dvd with DVD Architect

What do you suggest? getting a bit confused

[snapware]

I can't figure out how to burn a high bitrate ac3 stream with DVD Architect, can somebody please help?

In the project properties there is no option, and after i hit "Make DVD" then "optimize" it doesn't let me increase the bitrate for the audio. My mpg2 file is 2.5 gb, why is DVDA3.0 trying to recomrpess my audio to be a mere 82mb. Help please, thanks

[guns1inger]

Render the AC3 from the timeline, then import it into DVDA. From the timeline you can render it with however many channels you want, and whatever bitrate you need.

Under Files -> Properties -> Disc Properties Tab you can set the the audio format for the project (PCM, AC3 Stereo, AC3 5.1). After that, any bitrate should be acceptable.

[Cornucopia]

Once you've got the audio encoded (via Vegas) to the desired bitrate AC3, import, and then DON'T let DVDA "optimize" the audio. (You do have a choice). You either can't or shouldn't do it once it's already in DVDA.

Scott

[snapware]

I'm not even 100% certain vegas is converting the sound to ac3... It doesn't state what it uses when i make my original mpg2, cornucopia: i'm going to look now to see if i can avoid this "optimizing"

[guns1inger]

I always render video and audio out seperately from Vegas as elementary streams.

[snapware]

Guns1inger, if you render video & audio out seperatly, how do u make sure it's lined up correctly when u burn the final movie?

[snapware]

i rather keep them together do to the fact i'm scared of it not being synced up, but in my DVDA 3.0, it always makes me optimize the darn file

Connucopia, can you please open DVDA, and see if you can figure out how not to optimize the audio? this is weird

[guns1inger]

If they are in sync on the timeline, they will be in sync when authored. I author in DVD Lab Pro most of the itme anyway.

[snapware]

Anybody know how i can change the DVDA option to not force me to recompress my audio? I don't recompress the video, why do i need to recompress the audio? I can't figure this one out.

[Cornucopia]

Ok,

Vegas6:
Import, Put files in timeline, edit.
Then-[File | Render As...] and do export the file once as video (MPEG2) and once as audio (AC3). You can either use a stock DVD template or create your own if you know they're compliant.
Alternately, you could--
[Tools | Scripting |Batch Render] and select "Mainconcept MPEG2VDArchitectNTSC video stream" and "Dolby Digital AC3:StereoDVD"
Same difference. Both ways get you 2 separate elementary streams.
Make sure they're named the same except the extension (m2v, ac3) and in the same folder.

DVDA3:
Add your .m2v assets to the project's compilation. It automatically should associate the ac3. No "syncing" required.

[snapware]

niceeeeeeeeeeeeeeeeeeeee

I'm gonna give this a try tonight!

[Cornucopia]

Ok,

Vegas6:
Import, Put files in timeline, edit.
Then-[File | Render As...] and do export the file once as video (MPEG2) and once as audio (AC3). You can either use a stock DVD template or create your own if you know they're compliant.
Alternately, you could--
[Tools | Scripting |Batch Render] and select "Mainconcept MPEG2VDArchitectNTSC video stream" and "Dolby Digital AC3:StereoDVD"
Same difference. Both ways get you 2 separate elementary streams.
Make sure they're named the same except the extension (m2v, ac3) and in the same folder.

DVDA3:
Add your .m2v assets to the project's compilation. It automatically should associate the ac3. No "syncing" required.
Then--[File | MakeDVD] and [Prepare]
Select folder, NEXT, respond to messages (should be no bad ones).
Click on "Optimize", just to see what it says... (Alternately, you could have done [File | OptimizeDVD])
It shows the assets on the left, with Checks for Audio & Video streams (as well as est. size). Your assets SHOULD have green checks saying that everything's compliant and no need to change anything.
If they aren't green (yellow signposts or red signposts), look to the right pane and go to Video or Audio streams and see where it says "Recompress". This is a dropdown for either YES or NO.
If yes, you'll also be able to adjust the Recompress settings below it.
If NO, it's NOT DOING ANYTHING to the file.
You shouldn't need to do [Fit to Disc] unless you have to much for the available disc size, in which case clicking this will cause the "recompress" options to automatically be changed to "best" suit the apps expectations for disc size. If you're smart, you'll never let it decide for you. I only use this occasionally to see just what it's going to try to give me, so that I can go back and fix what needs to be fixed--MANUALLY--and then re-import and re-author.

That's all there is to it.
If it's in sync in Vegas, it's never been out of sync in DVDA or on the dvd disc (at least in my experience).

Scott


>>>>>>>>>>>>>>>>>>>>
edit: Sorry about that unfinished post earlier.

[snapware]

Scott, the way my mpg2 file was being read into DVDA, the drop down menu for recompress "yes / no" was greyed out under audio. That is why i could never figure this damn thing out. But your suggestion to render both audio / video seperately looks like it should work, will post updates tonight