dolby ac3 created on PC, doesn't work with intel macs....

[Jesse Peterson]

I'm on a PC system and I've run into this twice this week. I prep a dolby file and send it off so they can make their dvds.. and they can't inport it into dvd studio using their intel based macs. I've been able to walk them through the settings so they can create their own using the same settings and everything ultimately turned out fine. But is there a work around for this that I don't know about? Anyone else run into this?

[Andrew Mottl]

Just a thought... are you creating the AC3 files from 16 bit or 24 bit masters?

[Jesse Peterson]

16bit ac3's from dithered 24bit masters

But I also saw this
DVD Studio Pro: AC-3 (Dolby Digital) audio may not play back in HD DVD projects

problem may be limited to HD DVD?

[danijel]

I doubt it's a mac/pc issue. Have you tried creating AC3 in a different software? If you're using some commercial encoder, try BeSweet/BeLight - it's free, and works for when I send to mac.

[neilwilkes]

Originally Posted by danijel

I doubt it's a mac/pc issue. Have you tried creating AC3 in a different software? If you're using some commercial encoder, try BeSweet/BeLight - it's free, and works for when I send to mac.

NEVER use this encoder - it is a back engineered hack job that cannot reliably produce DVD compliant output. It will also fail Dolby Labs logo testing.

Additionally, do NOT use dithered 16-bit files either.
Stick to 24-bit fixed, and you will get a better result.
When encoding for DVD, you should be automatically in the correct format.
What encoder are you using, as a matter of interest - not all arecreated equally, and you should be using one listed at
Dolby - Licensed and Approved Dolby Digital Professional Encoder Manufacturers Each of the following companies manufactures various types and models of Dolby® Digital professional encoder products, including both software and hardware encoders. All
to ensure proper compatibility.

DD/AC3 is not free technology, it is licensed, and BeSweet/FFMPEG and the ilk are all hacks.

[danijel]

Originally Posted by neilwilkes

NEVER use this encoder - it is a back engineered hack job that cannot reliably produce DVD compliant output. It will also fail Dolby Labs logo testing.

Have you actually had experience with a BeSweet encoded AC3 (or heard of one) that hasn't worked on a particular DVD player, or are you just saying that it's potentially unreliable?

What is a Dolby Labs logo testing? (googling gave me noting)
Anyway, if you don't use the Dolby logo, BeSweet is perfectly legal.

[Andrew Mottl]

@Neil: Just a short question - I think I remember you recommending to indeed ONLY use 16 bit dithered files, as some cheap DVD players just trancate (drop) the last 8 bits when receiving 24bit audio. What made you change your mind? Any new info on the topic?

Thanks in advance for sharing!

[Jesse Peterson]

I'm using the nuendo DDE. Honestly, dithered or not, they sound and play back the same on my home system, but that's just my system, I try to be safe.

I've read about a 3rd party update called A52codec for intel macs, this update allows them to recognize ac3 when attached to quicktime. unfortunately, I havn't found a mac using client that is tech savy enough to test this on. I don't know if that's a global thing that'll let them import my AC3's or what. Just a weird thing

[neilwilkes]

Originally Posted by Andrew Mottl

@Neil: Just a short question - I think I remember you recommending to indeed ONLY use 16 bit dithered files, as some cheap DVD players just trancate (drop) the last 8 bits when receiving 24bit audio. What made you change your mind? Any new info on the topic?

Thanks in advance for sharing!

Andrew.
That is the recommendation for LPCM audio. With AC3/Dolby Digital, the recommendation is to use 24-bit files as it is a perceptual process & it just plain works better.
With LPCM, although up to 24/96 is optionally supported there are many players that do not output this. One of the more recent examples is the (expensive) upscaling Cambridge Audio 540MkII Azur unit. Whilst the picture quality is truly exceptional, it's LPCM output is 16-bit only at up to 96KHz, which is pointless given 24/48 is actually (IMSHO) higher resolution than 16/96 is.
The rule of thumb is essentially that unless there is a firmware option to set that states 24-bit output, or it specifically states it in the manual, then it is truncated to 16 bits. Sadly, this is far too common. Blame CD compatibility if you like, but it's in reality down to lazy firmware coding.

@ danijel.
BeSweet is a reverse engineered hack. It cannot reliably produce properly DVD compliant output. Period. This is *not* free technology, it is licensed.
And to be brutally honest with you, if you have no idea what the Dolby Logo licensing is then you should not be creating DVD Video discs for sale & replication.
And you should not legally be using any mention of Dolby Digital on your packaging either.
Go read all about it at Dolby Labs website. You are looking for the TMA agreements. I will not give links, consider it a research job that should have already been done

@jesse.
I also use the Nuendo DDE (This is actually covered under the Dolby Labs licensing so you are eligible for a TMA as well) and believe the issue may be a setting in your encoder or a need for an update as there have been issues lately.
What version are you using - is it the latest in N4,. or an earlier build in N3?
I ask as I have created many AC3 files and never had a single issue with any one of them yet (including the rare occasions where I deliver for someone else to author in Maestro, Scenarist etc. As DVDSP is not commonly seen by me, it is hard to say - but I would be very surprised if one of my DD files had *not* been imported to it somewhere along the line, (although it is a poor version of what was Maestro after Apple ballsed it up when they took over Spruce), and to re-iterate - you certainly should *not* be using nasty hack encoders.
Don't know about this new Codec either - but what I will certainly do is find someone with DVDSP on an Intel Mac & send them an AC3 from my DDE to see what we see.
I recommend trying the very latest update at
Dolby Digital Encoder :: Steinberg Media Technologies GmbH :: www.steinberg.net

[danijel]

Originally Posted by neilwilkes

@ danijel.
BeSweet is a reverse engineered hack. It cannot reliably produce properly DVD compliant output. Period. This is *not* free technology, it is licensed.

You're right - I just found out - AC3 has patents built in, and ac3enc (what BeSweet uses) is not legal for commercial use: How legal is ac3enc.dll [Archive] - Doom9's Forum
I obviously didn't understand the info at the Dolby site - I thought that the only advantage of signing a TM agreement and using an approved encoder over a hacked one is that you can use their logo in print and trailer on the DVD. As it turns out, signing TMA is the only way to produce a commercial DVD with AC3.

Originally Posted by neilwilkes

And to be brutally honest with you, if you have no idea what the Dolby Logo licensing is then you should not be creating DVD Video discs for sale & replication.
And you should not legally be using any mention of Dolby Digital on your packaging either.
Go read all about it at Dolby Labs website. You are looking for the TMA agreements. I will not give links, consider it a research job that should have already been done

I said I can't find anything on this 'Dolby Labs logo testing' that you mention, not Logo licensing or TMA.

Neil, I highly appreciate your input - I'm aware you're an expert on encoding technologies, and have read many of your posts in different places on the net. After all, if there wasn't for your post, I would potentially be in legal problem with BeSweet (although, I don't encode myself for the past couple of years). But I have to say that your response sounded hostile ('brutally honest', 'if you have no idea', 'go read' etc). However, no offense taken, as this is really not your usual tone, and everyone can get nervous from time to time.
Looking forward to further corrections on your part, should I unintentionally give out incorrect info in the future.

[neilwilkes]

I was not intending to come over as hostile, and apologise unreservedly for giving this impression!
What I was trying to say was that this is really basic stuff that is all easy enough to discover, and I guess that I got the tone wrong.

For TMA/Logo Licensing:
Dolby - Getting Licensed Â* We want to help your company succeed. Our licensing process supports Dolby’s quality standards, protecting the integrity of both your products and the technology itself. The process also begins your ongoing partnership w
(This is linked from the standard consumer site, but you need to go in from the so-called "Pro" portal these days it would seem. Dobly have altered their website somewhat since I last went there. It's at
Dolby - Professional – Movies, Broadcast, Pro Audio, Gaming, Live Sound & Video
The logo testing (as it used to be called, but that also now seems out of date) is mentioned at the first link, Step 4 - where you are supposed to submit samples of the encoded material to Dolby for approval - this includes packaging (for logo placement & correct Trademark usage) and the actual disc so that they can decode and analyze the bitstream to ensure compliance.
The content owners will certainly need a TMA to release a DVD with Dolby Digital marked on the packaging in any way at all - but the rules seem to keep changing and it is kind of tough keeping up with it all.
Getting the TMA is free - unless you include the cost of the En/Decoders.

IMHO it is well worth doing.

[danijel]

Originally Posted by neilwilkes

For TMA/Logo Licensing:

Thanks, that's clear now.

What's still a little confusing to me (after reading through it all): it appears that every time you finish off an encode (and want to use the DD trailer), you MUST send them the whole final product, so they check both the audio quality and the logo usage.... Dolby - Dolby Logos for Games, Videos and Recordings
Is it possible that they do that for every damn DVD that gets published around the globe.... FOR FREE?

[neilwilkes]

I've often wondered this myself.
Still - I was always taught to do things properly - if you don't give people a stick they cannot beat you with it.

DTS, on the other hand, could not be more relaxed about things.

[minister]

My understanding is when you purchase a legitimate AC3 encoder, the license fee is rolled into the price. Kinda like the record companies getting a cut of tape sales.... AFAIK, Dolby does not check DVD's. If you want a copy of their Logo art, you have to submit. If you don't need the logo art, then you are free to just make the AC3 and put it out there. Obviously for 35MM this is different.

[neilwilkes]

Originally Posted by minister

My understanding is when you purchase a legitimate AC3 encoder, the license fee is rolled into the price. Kinda like the record companies getting a cut of tape sales.... AFAIK, Dolby does not check DVD's. If you want a copy of their Logo art, you have to submit. If you don't need the logo art, then you are free to just make the AC3 and put it out there. Obviously for 35MM this is different.

If you want to use the logo art, you must submit.
The content owners need to have a TMA in place with Dolby Labs.