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dick9
21st June 2003, 19:43
Now with Besweet / AC3machine it is possible to encode to Dolby Digital (DD, AC3) with 5.1 sound channels for free.
For me is the option to make an AC3 audio stream from 6 mono waves important. My main goal with Beseet is to make my own DVD's with 5.1 sound from home movies with stereo sound. I am still experimenting with the total process from home video to Dolby digital 5.1 DVD.

In the past video editing with a PC was synonym for a lot of trouble (audio and video not in sync, computer crashes, it took an age to render a few minutes video etc.). Now things are better. I am using Pinnacle Studio 8 (current version of this software is 8.5.21 / 8.7.23 beta). With this program you can capture and edit your video and author a DVD with menu's, scene selection and chapters. The program still has 'bugs', especially when working with DVD authoring / chapters, is not as stable as Adobe Premiere but it gives a great value for money and is an easy way for basic editing tasks. It is a pitty that the program doesn't support AC3 audio.

So to make a DD 5.1 DVD I have to do things in another way. Here are some thoughts / experiments from me.

Basic editing with the stereo track of the home movie is still possible with Studio. Than I export the movie as an AVI file and extract the stereo soundtrack from the avi file.

For creating the basic content of the surround, center and LFE channels of the AC3 soundtrack, I use the wave editor that came with my soundcard (SB Audigy 2, Creative Wavestudio, stable and quick even with large files) and Magix Audio Studio 2003 DeLuxe (not stable with large avi movie but with more options). The process I use to create the AC3 content is something like this :

-split the stereo wave in 2 mono waves and convert to 48 kHz, 16 bit : now you have the channels front left and front right;

- make 2 new wave files that will become the surround (back) channels. Calculate/ make this channels f.i. as below :
surround left = 0,8 * front left + 0.5 * (front left - front right)
surround right = 0,8 * front right + 0.5 * (front right - front left)
You can add some reverb and normalize the level (below the maximum of you want to be the LFE channel louder !).
Substracting can be done by mixing an inverted waveform and a not inverted waveform.

- make a new wave files that will become the center (front) channel. Calculate/ make this channel f.i. as below :
center = 0,5 * (front left + front right)

- make a new wave files that will become the LFE channel. Calculate/ make this channel f.i. as below :
LFE = 0.5 * center
You have to low pass filter this channel (120 Hz), you can manipulate / enhance the bass sounds.
You can normalize to the maximum but I think this is not a good idea. Original this channel is ment to be an effect
("boom") channel, where the effects raise above the level of the other channels.

You can also add some extracted stereo information (front left - front right / front right - front left) to the front channels too.

- save the six waves.

The most interesting part is manipulating the 6 channels synchron with the video and to add special sound effects and "atmosphere", depending and synchron with the video of the movie. So you need a program with which you can see the video, hear the six mono waves at the same time and manipulate and mix the 6 audio tracks. With Magix Audio Studio 2003 you can couple a media file (avi) to a project to see the video and to hear the six waves at the same time (I use a setup with the Creative ASIO drivers for this). The audio manipulating options are o.k. but till now I am not total satisfied with this setup : not very stable with large AVI file (2 GB limit?) and slow manipulating big files (1 hour audio).
In Adobe Premiere (older version) I can place the sound tracks, but I can not hear them together. Till now I found no way to make the output 6 channel instead of stereo (does somebody know a workaround, directX / driver / setting manipulation ?).

With Besweet you can encode the six mono waves to the AC3 file (read my other thread about the 5. 0 / 5.1 bug).

Export in Studio the original movie to a MPEG2 file (DVD template) or use TMPGenc.

If your DVD authoring software doesn't support the input of seperate audio en video streams, you can demultiplex / multiplex MPEG and AC3 files also in TMPGEnc.

Use for DVD authoring f.i. DVD-LAB from Mediachance (www.mediachance.com; free time limited trial available, supports AC3).

Burn the DVD with Nero that came with your DVD recorder.

As you can see, the process is time intensive, not so easy and requires a lot of programs. This all just for the pleasure of 5.1 sound. I ask the community :

a Suggestions for a better workflow?

b Suggestions for a better creation of content for the
surround, center and LFE channels?

c Suggestions for a (better) use of software?

d Suggestions for cheating standard software (Studio 8 /
Premiere) to accept AC3 or to let them play 6 mono waves at
the same time ?

e Is frameserving from AC3 files to Studio 8 possible with
Avisynth? Has anybody tried this?

f Is it possible to demultiplex the VOB files created with
Studio 8, to replace the sound with an ac3 stream and
to multiplex to a new VOB that is working correct with all
the original features (like scene selection)?
Has anybody tried this?


As software I like most freeware, cheap shareware, not crippled demo's with only a time restriction and commercial programs with a "normal" price for an amateur. Till know I didn't find "the killer application" that has all and cost less than 150 euro. Till now just experiments !

I am curious at the experiments from other people. Let the community hear your voice !


Dick

dick9
22nd June 2003, 08:15
B.T.W.
I am exploring the thread / guide "A Guide from Stereo to 5 channel Surround" too. This thread has a lot of information about content creation for the sound channels.

If you are interested in this thread, certainly you are in the thread mentioned above too.

Dick

daphy
9th February 2004, 09:04
Hi dick,

(I know thid thread is an old one but I hope you are still intereseted on ideas, ´cause this theme is exactly what I am trying to do ;) )
b Suggestions for a better creation of content for the First I would like to invide you (and of course all the others) to our FTP-Server (ftp://daphy.mine.nu) which contains many diffrent solutions for making a 5.0/5.1 stream - you´ll find a collection of ideas there from the comunity depending on the sticky thread Stereo to 5-Channel Surround (http://forum.doom9.org/showthread.php?threadid=60137).
For adding sound streams on a existing DVD I´ve found two interesting threads:
Thread 1 (http://forum.doom9.org/showthread.php?s=&threadid=67348),

Thread 2 (http://forum.doom9.org/showthread.php?s=&threadid=64555)
but I have to check this out!

a Suggestions for a better workflow?
c Suggestions for a (better) use of software?

I wrote a guide in October (http://forum.doom9.org/showthread.php?s=&postid=382295#post382295) which shurely needs some improvement (meanwhile) :rolleyes:

That´s it for the moment

CYA Daphy

sharkatec
9th February 2004, 10:59
hi all,

ive tried 2 do exactly the same thing, from 2 channel stereo 2 dd5.1(ac3),but my problem was that if ive a movie with cdr track,it was no problem 2 make the 6 mono wav's,but with an avi with vbr audio,there were the problems skyhigh,i still didnt figure it out how 2 make 6 mono wav's from 2 channel stereo vbr audio, if i make them the output mono wav's are 3x the normal speed and length. does anybody has the same problems???? i use virtual dubmod 4 extracting the audio and besweet guide 4 trying 2 make the 6 mono wav's out of the 2 channel vbr audio.

daphy
9th February 2004, 11:17
with an avi with vbr audio,there were the problems skyhigh,i still didnt figure it out how 2 make 6 mono wav's from 2 channel stereo vbr audio

do you mean ACM WAVs?

have you tried to convert them into 'regular' (uncompressed) 16bit48KHz PCM WAVs befor you start with the 'besweet guide'( :confused: which one do you mean - I guess the sticky Ambisonic Guide from EOH)

CYA Daphy

sharkatec
9th February 2004, 12:24
no,it wasnt the sticky guide,cant come up with his name right now,and yes, i have decompressed the whole avi with avi2vcd,there is a decompresser in it,which result in an avi with an audiotrack of 1.5 gig.but its still not a cbr file then,i cant figure out the problem,i used the decompresser because the well known error in virtualdubmod about vbr audio,if i use the decompressor,the error is gone:) ,but the end result is still the same, 6 mono wav's with tripple the normal speed:sly:

dick9
11th February 2004, 19:41
Daphy,

I tried the Ambisonics and the Ambiosonics method.
I haven't tried the impuls response (SIR) method yet.

Sometimes I like Ambisionics, sometimes Ambiosonics and sometimes I prefer just Stereo 4.

It all depends on the source material (in my opinion).

Till now, I dindn't find the "super method" that is the best in all cases. Or did I miss something???

daphy
13th February 2004, 08:59
@ dick9

have you ever tried the Ambiophonic Methode from species_8472?

give em a try!

4.0 -> David did such a bidule (see layouts - Ambisonic)

@ sharkatec

but the end result is still the same, 6 mono wav's with tripple the normal speed

check preferences in bidule - guess you have choosen a diffrent samplingrate as your source file there ;)

CYA Daphy