Nero recode + 5.1 audio question

[UGC]

Nero recode let me select 5.1 audio, but when played using TosLink connection (optical) from my computer to my stereo, I can't hear anything? It plays on my computer (which is only 2 channel) but not thru my stereo (which is Dolby 5.1). Media info says the audio is AAC LC-SBR? How do I get 5.1 out of this?

Do I have to have different stereo equipment or something for this to work?

I really want to keep the Dolby Digital 5.1 audio.

I am new at using H.264. I love the picture and would like to learn more about the audio. I appreciate any help you could give me.

[Sharktooth]

AAC is not DolbyDigital so your stereo cant decode it.
if you want to keep your DD track then you have to manually demux it with DGIndex, encode ONLY the video and remux video and audio into MKV (since DD-AC3 in MP4 is ugly).

NOTE: you can even re-encode your audio from AC3 to AC3 with a lower bitrate

[Dark Shikari]

There is no such thing as "AAC-LC-SBR"--Spectral Band Replication (SBR) is a feature of AAC-HE (AAC High Efficiency), not AAC-LC (AAC Low Complexity).

[Has123]

You can have AC3filter to decode/transcode to AC3 5.1.
or you can use ffdshow to do the job
http://forum.doom9.org/showthread.php?t=90385

[UGC]

Thanks for all the replies. I think I will try to remux AC3 into MKV container. Because I have a standalone that will play the H.264 in a MKV file. If I was playing just on the computer, I might use the AC3filter.

Now to find a guide on how to use DGIndex.

DGIndex will just mux the video and AC3 right? I will not have to reencode the mp4 of the video only that nero recode gives me correct?

*edit*
Just downloaded DGMPGDec, and opened up DGIndex. But it is not letting me open up the mp4 video only file made from nero recode.

[em500]

> DGIndex will just mux the video and AC3 right?

No, it demuxes the AC3 from MPEG/VOB.


> I will not have to reencode the mp4 of the video only that nero recode gives me correct?

Correct. You can demux the video portion of the mp4 with mp4box or YAMB.

If you want to keep using Nero for h.264 you can leave out the audio track in future Nero encodes alltogether, so the encoding will be a bit faster. Then pull out the h.264 video from the Nero mp4 with YAMB, get the AC3 stream from the VOBs with DGIndex, and mux them with the mkv tools.

[UGC]

thanks em500.

I am learning more every day. I'll give those a try.

*edit*
I found everything you mentioned, except the MKV Tools. What I found was mkvtoolnix? is this the same thing?

[foxyshadis]

There is no such thing as "AAC-LC-SBR"--Spectral Band Replication (SBR) is a feature of AAC-HE (AAC High Efficiency), not AAC-LC (AAC Low Complexity).

One of the standard names is MPEG2 AAC-LC+SBR, since that's exactly what it is, LC with SBR packets. It's only called HE in the mpeg4 variant, even though they're the same thing. That's just the way mediainfo reports it, so you'd have to ask zenitram to change it.

I found everything you mentioned, except the MKV Tools. What I found was mkvtoolnix? is this the same thing? Yes, that's the proper name for it.

[UGC]

Thanks a million everybody. It took me all of about 2 min to get it done.

A few notes for someone else that may have the same issue:

I read here, on this site, that nero 8 recode will let you keep the original AC3. I downloaded it and tried it, and it will not.

The MKV tools was able to use the mp4 "video only" file made by nero recode. I did not need to use Yamb. I did try it, but MKV tools did not know the frames per second of the raw data, so I tried the mp4, just to see what would happen, and it worked.

[UGC]

>
Correct. You can demux the video portion of the mp4 with mp4box or YAMB.

If you want to keep using Nero for h.264 you can leave out the audio track in future Nero encodes alltogether, so the encoding will be a bit faster. Then pull out the h.264 video from the Nero mp4 with YAMB, get the AC3 stream from the VOBs with DGIndex, and mux them with the mkv tools.

em500 I must apologize to you. You were correct. I must use YAMB to get the raw video from the mp4. Just muxing the mp4 "video only" that nero recode made with the original ac3 file left me with a movie that slowly got out of sync. The start of the movie was fine, but by the end, it was way off. Using the raw video from YAMB, with the same frame rate (23.976), muxing with MKVtools the movie was perfect from start to finish. Thank you.