mp2 audio

[bgamd]

I'm a longtime user of VideoStudio, currently using Pro X 7.
I have an application that calls for files to be rendered to the specs below. I'm baffled how to render audio as mp2. Any suggestions will be appreciated.

CREATING BROADCAST MPEG FILES WITH NON-LEIGHTRONIX SOURCES
The NEXUS series supports MPEG-1 and MPEG-2 video encoding standards. LEIGHTRONIX recommends the following guidelines for broadcast MPEG video files created with any third party hardware or software to ensure optimal playback on either of the internal NEXUS series MPEG players:
• Acceptable stream types:
MPEG-1 System Stream or MPEG-2 Program Stream (consisting of a single elementary video stream with an optional single elementary audio stream)
NOTE: Transport stream is not possible.
Elementary video stream
Three video resolutions (pixels) are allowed. Other resolutions are not supported.
352 x 240 (Horizontal x Vertical)
352 x 480
720 x 480
• Picture rate must be 29.97 pictures per second.
• A maximum bit rate of 10 Mb/s is allowed. Higher rates are not supported.
• National TV Standards Committee (NTSC) with 4:3 aspect ratio required.
• 4:2:0 sampling format required. (Main profile at Main or Low level, ≤ 10 Mb/s)
• IBBP group of pictures (GOP) structure recommended for best quality (30 frame maximum GOP size).
• Encode header information in stream every few seconds to aid in error recovery.

• Audio, if present, must be encoded into the MPEG file using Audio layer II.
• Audio may be encoded at a 32, 44.1, or 48KHz sampling frequency. LEIGHTRONIX recommends an audio sampling rate of 44.1 KHz for optimal performance.
• MPEG filenames may contain up to 27 characters (no spaces) in addition to the required “.mpg” extension.

[Ken Berry]

Those are rather strange specifications -- or rather, they would appear to be very old. They should produce a standard definition DVD, but only in 4:3 aspect ratio, rather than widescreen. And the frame sizes, apart from the full 720 x 480 are not going to give very good quality, just as using mpeg-1 video will not. That particular format is almost archaic these days.

What I find strangest, though, is the insistence on mp2 (also know as mpeg layer 2) audio since I have always been under the impression that that audio format was not part of the NTSC DVD standard, which specifies either standard (L)PCM audio or Dolby AC-3 -- though maybe at one time it was, given that those specs appear so old.

Mpeg-2 audio is compressed to a similar degree to AC-2 and produces a similar sized audio file. It is certainly a part of the PAL DVD standard, and I also use it regularly in high definition editing since one of my main sources of high def video is a HDV camcorder which uses it as its native audio format.

VS X7 can certainly output mp2 audio. But I would check to confirm there are no other alternative formats. I would do so since I understand that few if any NTSC DVD players will recognise that audio format. What specific application is it that requires this format? And is it to be burnt to an actual disc, or left in clip form?

[bgamd]

Thanks for the reply, Ken.
I need to render these mpg files (not dvds) in the format stated for ingestion into a hard drive used to supply video for a (very new!) Leightronix Ultranexus Television broadcast unit.
http://www.leightronix.com/products/ultranexus.php

Strange format, I agree, but need to do this if possible. By rendering the mpg files as requested, I am hoping to eliminate the added step of running them through yet another conversion program. Please explain how I can render these files (NTSC) as described in Videostudio Pro X7.
Specifically, there seems to be no availability for mp2 audio in any of the "share" functions that I can find.

[Ken Berry]

Hmmm.... I too cannot find output with mpeg layer 2 audio for anything except HDV, which of course is no good for you. Older versions of VS used to allow it for DVD-compatible mpeg-2 output, but I guess Corel must have dropped it at some time, probably because it was not suitable for use in NTSC DVDs... I'm sorry to have misled you, but it has been quite some time since I have used VS to produce DVDs as I almost exclusively edit high def video these days.

[bgamd]

Thank you for trying. I have a work around but it involves yet another step. Oh well!

[lata]

Hi Ken / bgamd

The last version to support Mpeg2 Audio as far as I am aware was VS12 (X2)
I was able to create a VSP using these settings, I then I render a short clip, attached to post.


MPEG files
24 bits, 720 x 480, 29.97 fps
Lower Field First
(DVD-NTSC), 4:3
Video data rate: Variable (Max. 8000 kbps)
Audio data rate: 224 kbps
MPEG audio layer 2, 48 KHz, Stereo

I was able to use that clip with X7, interestingly changing the project properties to match above.
From F6 - Show Messages being ticked.
Obviously do not try to edit those settings as MP2 Audio will be lost.
Share--render same as project properties and same as first clip seemed to work retaining Mpeg2 Audio

Using Batch Convert also retains the project properties so that option would also work.

Make Movie Profile Manager “Add” option unfortunately is a “no go”

MP2 Audio.zip

NTSC 4.3 Video + MP2 Audio.mpg

(4.3 KiB) Downloaded 182 times

[asik1]

The problem is encoding to mpeg2.
As I think most of the new stuff will be from current formats.
X8 holds few legacy ulead files that has MPEG2 audio as legit DVD format but I don't know about the actual encoding. unless I have a true mpeg2 audio piece to test.

[Ken Berry]

Thanks for that Trevor... Boy, was it that long ago???

Anyway, I tried it in both X7 and X8 and got the same results in both: same as you. We can at least use it to set the Project Properties to the required format, and then use Share > Same As Project Properties. So at least bgamd can output video to those archaic requirements. But as you said, trying to make a template from that file using the Add function returns the dreaded "File format mismatch" error. I even tried making a new file with those properties and then tried Add again, with the same negative result.

It is interesting that VS refuses to create a template based on that file since VS comes with the mpeg layer 2 codec and can clearly output it too. But I can only imagine VS sees it as an attempt to create a DVD profile using a property which is not part of the NTSC DVD standard, and thus refuses to proceed.

[asik1]

Ken, where do you go about trying to add this profile and get format mismatch?

** And what about this demand
"• Encode header information in stream every few seconds to aid in error recovery."

[lata]

Hi Ken

I am assuming the properties of that sample are correct, I guessed on lower field?
Maybe bgamd will confirm that?

If file sizes are not a problem then Constant bit rate may be more suitable, at least will improve render times?

[Ken Berry]

Hi Trevor -- I hadn't noticed that Field Order was missing from the specs. But at least it is possible to create a file with either UFF or LFF as long as you have X2!!

asik -- in VS > Settings > Movie Profile Manager, there are two ways to create a template. The first way is to simply create a new one from scratch using the New button. But there is also an Add button where you navigate to a clip with the exact properties you want to copy (shown as Path with a mysterious "..." button). I was using that when I got the File format mismatch error. If you can use that Add function successfully, it creates a template with the Properties you are after and it appears at the bottom of your templates list with the name you assign it, exactly the same as one created with New. The major difference is that the new Add template then becomes untouchable. You cannot edit it because if you try, it immediately reverts to a default mpeg-2 template.

[asik1]

Oh, I keep forgetting that option.
I'm not getting format mismatch but error 15099:3:1, file type not compatible....
I think it's curable by hacking few files.

But there is a simpler solution.
load MPg2 file, upon notice accept its settings.
Add all your current HD clips and edit your piece.
Share select "first clip" BUT... before render back and delete the unwanted clip
than uncheck "first clip" and render as project.

I was able to render HD "pal" file to the DVD mpeg2 ntsc settings.

[lata]

Hi Guys

I have managed to use Format Factory to create a MPEG 2 Audio file.

NTSC drop frame (29.97 fps)
MPEG files
24 bits, 720 x 480, 29.97 fps
Frame-based
(MPEG-2), 4:3
Video data rate: Variable (Max. 9000 kbps)
Audio data rate: 224 kbps
MPEG audio layer 2, 44.1 KHz, Stereo

Does not activate Show Messages so cannot match Project Properties also uses Frame Based only? but does allow for Same as First Clip rendering?

Video Studio X2 (VS12) is easier to use to set properties.

[Ken Berry]

asik -- we know we can do that using a one-by-one approach. The point was trying to build a permanent template since the poster is going to be doing this a lot.

[asik1]

asik -- we know we can do that using a one-by-one approach. The point was trying to build a permanent template since the poster is going to be doing this a lot.

If so, all he needs is a 3 seconds of legit mpeg2 black video clip to fade his projects from and all is solved.