MP4/AAC -> XVid/AC3 6ch

[brugi]

Hi all,

First, pardon me if the question was answered before. If so, I couldn't find it. Second, I'm a noob.

As subject says, I'm trying to convert MP4/AAC to XVid/AC3 6ch so I can play it on my standalone DVD player. Whatever I try, video comes out fine, but audio doesn't. Converting to MP3 2ch audio works like a charm, but I really want 6 channels.

I've tried with FormatFactory first. VLC (Codec Info) shows that correct audio stream is preset, but I can't hear any sound, neither on computer or standalone player. Then I've read somewhere that FF has problems with encoding AC3, so I've uninstalled it and tried with other programs.

Whatever I tried (SUPER, XVid4PSP, ...) the same problem remains (some other too, but they don't support MP4). I've also tried to reinstall codecs (K-Lite and AC3filter), but no change.

I'm almost sure that this has something to do with my computer, but I'm really not competent enough to figure out what.

Does anyone have a suggestion for me? Thank you in advance!

/b

[guns1inger]

Does the original actually have 6 channels ? Mediainfo can tell you if it does. If it doesn't, why bother trying to create something that isn't there ?

[brugi]

Does the original actually have 6 channels ?

Yes, original sound is 6 channel (AAC encoded, which my standalone player doesn't like).

[Bonie81]

As subject says, I'm trying to convert MP4/AAC to XVid/AC3 6ch so I can play it on my standalone DVD player. Whatever I try, video comes out fine, but audio doesn't. Converting to MP3 2ch audio works like a charm, but I really want 6 channels.

- Simple advice please do not try to convert AAC (2ch or 6 ch) to AC3 (6ch), why?
AAC follows different channel mixing algorithm than AC3, so even you are successful to convert it to AC3 (6ch), it sounds crappy.
Albeit AAC (6ch) can be used to fake AC3 (6ch), but pro-listener can easily find the difference.

I've tried with FormatFactory first. VLC (Codec Info) shows that correct audio stream is preset, but I can't hear any sound, neither on computer or standalone player. Then I've read somewhere that FF has problems with encoding AC3, so I've uninstalled it and tried with other programs.

- All the softwares as far as I know, they can Downmix AC3 perfectly.
For AC3 - 6 channels Original Source bearing AC3 6 channels or DTS is highly recommended.

Whatever I tried (SUPER, XVid4PSP, ...) the same problem remains (some other too, but they don't support MP4). I've also tried to reinstall codecs (K-Lite and AC3filter), but no change.
/b

- Nothing much to with computer settings. As said before, Original Source bearing AC3 6 channels or DTS is highly recommended coz original channels are recoded through professional channel mixers. No software can give you that SoundLab effect.

May be. AAC (2ch or 6 ch) ---> AC3 (2ch) may go good, any many softwares probably convert it without problem.
Somehow, it is solely my personal experience. i like mp3 (2 ch lame 3.98.4) in stand-alone DVD/DiVx Player

[brugi]

May be. AAC (2ch or 6 ch) ---> AC3 (2ch) may go good, any many softwares probably convert it without problem. Somehow, it is solely my personal experience. i like mp3 (2 ch lame 3.98.4) in stand-alone DVD/DiVx Player

Thank you for the extensive answer. My failures make much more sense now.

Converting to MP3 2ch works okay. So, should I give up on 6ch? Maybe there's another tool that will allow me to create a "regular" DVD instead of encoding it to XVid/AC3?

[guns1inger]

AVStoDVD can convert 6 channel AAC to 6 channel AC3. It can also output elemenatry streams, so you could mux the AC3 into an AVI with Xvid if you wanted to.

[live4fun]

This will be little complicated. even though you succeeded to creating aac to ac3, the result will be wrong channel order in final out put file.

Try the below method it may work for you.
use nero wave editor (ultra 7 version) to convert 5.1 aac to 5.1ac3. then mux with mp4muxer. you will get mp4 with ac3 5.1
then convert to xvid. you will get xvid with ac3 5.1.

[Bonie81]

from guns1inger reply,
just the idea that might work,
convert MP4/AAC to XViD/mp3 (DVD-SD) first then use AVStoDVD, might be successful to get ac3 6 channels.

[guns1inger]

AVSroDVD understands the correct channel order (as do most tools nowadays)

[Bonie81]

hi guns1inger;

AVSroDVD understands the correct channel order (as do most tools nowadays)

1) Are you taking about mp4-->ac3 6 ch. through avstodvd?
-or-
2) mp3 2ch--->ac3 6ch through avstodvd? (i guess most of the DVD Authroing Tools will be able to convert mp3-->ac3 6 ch.)

Have you tried either 1) or 2) by yourself? How was the result?
I will trying to evaluate AVStoDVD on my friends machine having Windows as OS.

[Bonie81]

just did a short test run with avstodvd.
two things i can not figure-out
1) audio settings for ac3 5.1 ss
2) and dvd menu
but, overall, i like the tool coz it give very good quality and runs HcEnc as backbone.
finally, who da care ya 5.1 and menu? just enjoy 1 hr nice quality dvd straight.

[_MrC_]

just did a short test run with avstodvd.
two things i can not figure-out
1) audio settings for ac3 5.1 ss
2) and dvd menu
but, overall, i like the tool coz it give very good quality and runs HcEnc as backbone.
finally, who da care ya 5.1 and menu? just enjoy 1 hr nice quality dvd straight.

Thanks for the appreciation, but, could you elaborate a bit more point 1 and 2? Eventually take a look at the Help section for basic details and ask here for more.



Bye

[Bonie81]

[QUOTE=_MrC_;2023266]

Thanks for the appreciation, but, could you elaborate a bit more point 1 and 2? Eventually take a look at the Help section for basic details and ask here for more.
Bye

_MrC_
AVStoDVD Author

First of all, Thanks for your nice 'n' free tool, and...
thanks for the response too.

I have figured out what i missed in dvd menu is to click the menu tab. basic dvd-menu is satisfactory (need little more cosmetics).

I wonder how avi (XViD + AC3 2ch) will be rendered?
Will it be rendered as vob + ac3 2ch or it would be possible to upmix to vob + ac3 5.1 ch using AVStoDVD?


While the title of this thread is MP4/AAC -> XVid/AC3 6ch.
I would prefer MP4/AAC -> XVid/AC3 2ch coz while playing DVD Dolby (AC3) 2 channel in home theatre system.
Hardware decoder is able to upmix 2 ch into 5.1 or 7.1 ch perfectly.
As DVD (dolby 2ch) sounds great, and anyone still having strong preference for 5.1ch,
it would be better to capture the video..

[_MrC_]

I wonder how avi (XViD + AC3 2ch) will be rendered?
Will it be rendered as vob + ac3 2ch or it would be possible to upmix to vob + ac3 5.1 ch using AVStoDVD?

AVStoDVD cannot do channels upmix.

If you leave default preferences, then the AC3 track will be demuxed and kept as it is in the final DVD. Instead if you choose to re-encode audio, then channels options will be 1.0 and 2.0.

In the latter case, remember to properly setup your directshow audio filter mixer (it could be AC3Filter of ffdshow, if ffdshow then AVStoDVD will take care to adjust it automatically).



Bye

[Bonie81]

AVStoDVD cannot do channels upmix.

If you leave default preferences, then the AC3 track will be demuxed and kept as it is in the final DVD. Instead if you choose to re-encode audio, then channels options will be 1.0 and 2.0.

In the latter case, remember to properly setup your directshow audio filter mixer (it could be AC3Filter of ffdshow, if ffdshow then AVStoDVD will take care to adjust it automatically).



Bye

Thanks for the reply.
As AC3 2ch plays just excellent on my system. So I wud prefer to keep AC3 2ch (which is also most compatible with all most all stand-alone DVD Players) as is in the final DVD. In the case of AC3 5.1 ch, I will try to render avi + ac3 5.1 ch.

[thesourmango]

This being quite an old thread, some things must have changed during these last 4 years?

I use avidemux to convert my movies from 6ch AAC (MP4, AVC+AAC) to 6ch AC3 (MKV, AVC+AC3).
My Logitech Z-5450 detects the AC3 as DTS whereas the AAC is detected as stereo (or alternatively upmixed using ProLogic II)

If someone could explain more as to how avidemux manages to convert the sound, how the channels differ or what channel is rendered "wrong", or why the AC3 "sounds crappy", or why differences "would easily be detected by a pro" I would be very thankful

some additional info:
I used mediainfo to confirm the audiostreams both before and after the conversion.
Both file extensions are .mp4.
In avidemux i use the presets "copy" for video and "AC3 (lav)" for audio. I havent tried AC3 (aften) and do not know the difference between the two.

[redwudz]

I use AVIDemux mostly for editing, not conversions. Not sure about your source, but I prefer VidCoder for video>MKV(H.264) with AC3 encodes. I convert all my video files to AC3 (Usually surround sound) and use H.264 for most all my video encodes. Even my BD player seems to be ok with this format.

We probably have some AVIDemux experts here that can answer your other questions.

*Really, if you have a new topic, best to start a new thread. You can link to older threads as you like, but we discourage adding on to very old threads with new questions as it makes it harder for other members searching for 'up to date' answers for a topic.

And welcome to our forums.

Moderator redwudz