AC3 to DTS?

[Sakuya]

Hello. Is there really a need to convert AC3 to DTS for DVD? I have an AC3 file that is Dolby Digital 5.1 surround sound. What difference does it make if I converted it to DTS?

[adam]

It wouldn't make any difference at all. DTS is a different compression format, which in some ways is superior to AC3. But once its been compressed to AC3, any benefit that could have been achieved using DTS is lost. Besides that, most people can't hear the difference between the two formats anyway.

DTS does have the capability to support additional channels of information. But just using the AC3 source off the DVD, you are not going to be able to remix it any better.

[Sakuya]

I know this is hopeless. But for some reason, my DVD player can only play my DVD+R when it has AC3 sound. When it is normal MPEG sound, it is silent. So the DVD project I'm working on is that the movie has AC3 sound but the extra video trailers I want to add is at a VCD standard. When I play it on my DVD player, the movie plays with sound but the trailer clips are silent. So how do I convert the audio to AC3 (as well as changing it to 48000Hz)? I tried using BeSweetGUI and the log says:

BeSweet v1.5b25 by DSPguru.
--------------------------
Using hip.dll v1.19 by Myers Carpenter <myers@users.sf.net>
Error 85: support for ac3enc.dll had been removed due it its suckness!
Quiting...
[00:00:00:000] Conversion Completed !

Logging ends : 04/11/04 , 17:49:57.

[adam]

Well if you are in a country that uses NTSC this is no suprise at all, since mpeg audio is not supported in the NTSC standard.

Yes AC3 support was recently removed from BeSweet but if I'm not mistaken in the very latest version it reimplemented AC3 support. So you can either get the latest version or an earlier version. There are also other free alternatives like Headac3. Or you can invest in a commercial AC3 encoder like Soft Encode. All of the above programs also let you resample the audio to 48kHz.

Finally, you could decompress the audio to LCPM wav. It takes up much more space but is supported in the NTSC standard and there are a number of free programs which can export it. Also since these are trailers, the audio is not going to take up all that much space.

[Sakuya]

Thanks. I downloaded the newest beta version because they said in the change lot that they enabled AC3 conversion again. The AC3 files all work. I'm so proud of myself! How do I know if they're 2 channel or 6 channel? They were originally stereo so...I was confused by all the options in BeSweet.