converting/authoring an original concert DVD

[theDruid]

Hi all,

I've had a PM from Marius about a project he's working on.

I can't really help much, so he's agreed for me to post it in the forum to let everyone else have a look:

Hello,

I am Marius Perron in San Antonio. For many years I have been an audio man – I know very little about video. I own a school called the Audio Enginearing Institute: www.audio-eng.com

I am hoping you can help me with DVD video. I am in the middle of doing my first 5.1 surround DVD. Last month I recorded a live concert of an artist named David Kauffman (I did the multitrack audio). A company called CTSA shot some video. We are now in the process of putting together a "video" of his concert on DVD.

The complete concert is about 120 minutes long. To keep the files small, the video company is editing each song as a separate file. I asked them to give the video files to me in the MPEG-2 format, so they are ready for the DVD. Each video starts and ends with the applause so the concert appears to be seamless when you play them in sequence.

I will do my audio mixes with Steinberg Nuendo and encode each song as an AC-3 file. Now we have ten video files and ten audio files ready for the DVD.

When I asked the video company to give me MPEG-2 files, I didn’t realize that you could create MPEG-2’s at different bitrates! They have delivered four of the ten files to me. After investigating those first four MPEG-2’s, (I put them into the “Bitrate Viewer” utility) it looks like they were encoded at 8 mbps. We will need to have the bitrate at about 5 to be able to fit 2 hours on a DVD-5. (The video company does television every day – they are new to the DVD world. They are working with a PC based program called Video Toaster.)

My question is this. Can I convert the present 8 mbps MPEG-2 files to 5 mbps MPEG-2 without degrading the video quality?

Our completed DVD will be a typical "concert" DVD – the user will see a menu when he starts the DVD. At that point he can play the complete program, or he can go to a submenu where he can choose which individual song he wants to hear.

What authoring software should I buy that I will be able to bring the 10 video and audio files into the program, and have a menu that can select an individual song?

Or, do I need to combine the 10 videos into one huge long video; and combine the audio into one file (using Vegas) and then bring these into my DVD creation software?

I am a little apprehensive about using the LONG files… audio-video sync problems will be much more obvious after 140 minutes than it will be through an individual song.

I would appreciate any light you can shed on this situation.

Marius Perron

I have told Marius that if he reduces the bitrate of the video, there will be some quality loss in theory, as some data will have to be discarded in compressing the video more. However, I've also said that as long as the video is kept at a respectable DVD bitrate, the perceptible quality shouldn't suffer too much.

So, it's over to everyone else to "shed some light on this situation"....

cheers,
mcdruid.

[Gees]

He PMed me too. :c* Ok how many others did he send this out to hoping for personal one-on-one help?

- I replied by advising him to the read the guides. And told him it was impossible to reduce bitrate from 8000 to 5000 with no quality loss.

All the info is there. Is he still looking for an easy way out?

You have a bigger heart than I do, Druid. :cD

[theDruid]

not so sure about that Gees - I just can't say no! :P

Actually, looking back through the message, I'd say it can be boiled down to something a lot simpler:

1. Gees and I (and probably others by the sounds of things) have answered the easy one - no reduction in bitrate without some loss of quality.

2. Do you need to combine all the files together? - I don't think so... but I'm not an expert on DVD authoring.

3. What authoring software should he use/buy? - I'm not the person to ask as I don't have a DVD-burner (yet!)

anyone.... bueller.... bueller.... fry....

[housepig]

I got one as well.

responded as above - quality will take a hit, but try a segment and see how bad it looks - if the source is super clean, it may be an acceptable tradeoff in quality vs. size.

for authoring - depends on the software budget. DVD Lab will do nice work, unless you need a "play all" and a "play one and return to menu" option, without room on the disc for two sets of files.

[Gees]

Well, my problem with all this - and yes, it's a personal opinion, because he PMed me :c) - is that it seems to me that ,whoever this is, he is probably getting paid big money for this project, but had not looked into the fact that mpeg can have different bitrates?

And then throws a bunch of PMs to people looking to salvage this huge oversight within a day of signing on as a member?

Sorry. I don't like the tactic. And I don't like the imposition on you in asking you to post his PM for him so he can easily find the answers all in one handy place.

If he has Vegas - or access to Vegas - which is better than anything I've got - then I think it's a fair guess he has access and means to sort this without broadshot PMs.

[theDruid]

I don't like the imposition on you in asking you to post his PM for him so he can easily find the answers all in one handy place.

He didn't ask me actually Gees, I suggested it was a better way of going about it.

I didn't realise at the time he'd spammed anyone with more than a hundred posts!!

Can I do a Gees then? ...

Marius read the guides about DVD authoring, and do a search or two - there are dozens of topics about what software people recommend.

cheers,
mcdruid.

[Gees]

Can I do a Gees then?

Sure! It's not patented yet! :cD

PS - I suggested he post his own question. Must be a really shy guy! :cD

PSS I am also suspicious of the unneccessary, but handy, inclusion of his "Audio Enginearing Institute" sic.

Hmmmm :c*

[theDruid]

I was just thinking that you don't have a Sent items folder in your PM box, and it would be a pain to type it all out again - but it looks like he must know how to use copy and paste!

[Gees]

He knows how to get some free advertising too.

[Tommyknocker]

He also emailed me. I started to give him the link to the guide I wrote, just told him to reply if he was interested.

[theDruid]

He knows how to get some free advertising too.

Well they say there's no such thing as bad publicity, but I wouldn't have thought people would be queuing up to get him to do their concert DVD's just yet.

Look - I'm not trying to be rude here - I'm sure this guy knows his stuff about audio recording.

Just maybe he'll come to realise that PM'ing everyone is not the best way of getting help from this forum.

I don't even want to go back over what happened when we all got spammed about those media forums.

[Gees]

Exactly. :c)

[bugster]

He e-mailed me too. Havn't had chance to reply yet, don't think I will bother now.

If he wanted more than one answer/opinion he should have posted to the forum in the first place.

[Gees]

I got a reply to my response that said, "Thank you Mr. Gees".

Got a chuckle out of it at least. :cD

[Tommyknocker]

If he used email, he was able to see who actually read the email, as opposed to how many people saw it.

[ImaWeTodd]

I got a reply to my response that said, "Thank you Mr. Gees".

Dear Sir,



Respectfully,

ImaWeTodd

[Marius III]

Okay. Here I am. Marius Perron here.

I couldn't post last night because I registered last night. The forum makes a new user wait 24 hours.

I am sorry if I bothered anyone with the "Personal Messages", but I was needing information right away. I had gone through the most of the guides and articles. I don't think there is information anywhere on this site that addresses the situation of re-encoding an MPEG-2 file.

Of course I know the quality of a 4 mbps MPEG will not be as good as an 8 mbps MPEG. I guess I should have phrased my question this way, "If you start with an MPEG-2 at 8 mbps, is there a way to re-encode it as 4 mbps without EXTRA loss of quality".

I actually got some very helpful answers from some folks on this forum. I think I have thanked each one individually.

As far as advertising my school… I just included that so you would know that I wasn’t some kind of flake in his bedroom attempting computer multimedia for the first time.

I will do normal posts from now on.

[ImaWeTodd]

Was your question answered ?

I'd say in general you can not reduce the bitrate and maintain the same quality for a like type of encode.

However, a VBR encode with an avg of say 6k could easily be as good as a CBR encode at 8k. As in everything, it depends upon the source.

(A big pan of the crowd needs a lot of bits if you expect to see anything but a blur).

Some other things to note:

Any fresh re-encode is assumed to lower the quality, regardless of the bitrate. Again, if there is enough quality head room in the source, this may not be noticed.

With Transcoding, it is said that if you don't change the bitrate, you loose nothing. This is because the transcoder uses the info from the original encoder. Of course, changing the bitrate here does loose quality.

In conclusion, in your case you could use Pinnacle Instant Copy (considered the highest quality transcoder), or do a re-encode with CCE VBR multi-pass. If you drop the rate alot (50%), quality hounds say do CCE.

BTW: I just play at this stuff... not even near my real job.

[Marius III]

Thanks for the info.

It looks like the client is wanting to add MORE length to the DVD. The replication company told him about DVD9. So now it looks like we will have plenty of space - no conversion needed.

Now I need to learn about the pitfalls of DVD9. LEarning new stuff is a good thing, right?

[ImaWeTodd]

The replication company told him about DVD9.

This stuff is way past me and most here.


Hey... If you're an audio guy, can you give some tips in the audio Forum? Hope to you there.

For example: How do you get the source for 5.1? What do you put on the rears, LFE? Etc....

[Marius III]

You asked:

For example: How do you get the source for 5.1? What do you put on the rears, LFE? Etc....

You have to start with mutlitrack audio - that is - the bass on one track, the guitar on one track, etc. You mix those track in a program that will allow 5.1 as the mixdown foramt (Nuendo, Cubase, ProTools, Sonar (i think) )

After you have your six tracks from your mix (Front L and R, Rear L and R, Center, and LFE - you have to encode those tracks as an AC-3 file.

Listen to a typical concert DVD to get an indea of what to put in the rear and LFE. My good friend Fernie mixed the Dixie Chicks DVD - they have a nice one. Usually the rear is mostly "the room" - no close mics. You really don't have to put anything in the LFE - the bass management of the your playnack system will feeda little bit of every channel to the sub. I usually put a little kick and bass guitar down there. The dixie chicks only put the Acoustic BAss in the LFE...

[tito13kfm]

I thought I was special in being asked for personal help with a project from marius..

I just told him to get the original source tapes and do his own encoding