AC3 vs Dolby Surround compatible MP3

[StickHorsie]

Say there's this 3½ hour long DVD movie, of which I wanted to make a 2028 MB (1.98 GB) AVI.

Now I could have kept the 966 MB original AC3 audio, but that would've left only 1062 MB for the video part (including overhead), which isn't very much for 3½ hours. :p

So I converted the AC3 to a Dolby Surround compatible (dplii) 160 kbps VBR MP3, which was only 210 MB, which in turn left a LOT of extra available MBs for the video part (VERY big difference there).

Since I don't have mutant ears, this sounded just as good on my 2 speaker system, and since the MP3 is Dolby Surround compatible, I assume that friends with more advanced systems than mine would still get a surround signal, but (apart from not having separate center + LFE channels) would there be other real discernable differences?

[SeeMoreDigital]

Personally.... I would have generated a 6Ch AAC-LC audio stream (at 160Kbps) ;)

[FlimsyFeet]

I assume that friends with more advanced systems than mine would still get a surround signal
Screw your friends, it's your backup, do it however you want!

[tebasuna51]

Say there's this 3½ hour long DVD movie, of which I wanted to make a 2028 MB (1.98 GB) AVI.
...
(apart from not having separate center + LFE channels) would there be other real discernable differences?

DPL II can recover also the center channel and any audio equipment can extract the low frequencies to subwoofer then is a solution ...
if you need a backup in avi format (aac is not supported in avi) with less than 2 GB (to be burn in standard DVD data) to be played by standard standalone players.

For a 3½ hour long movie is a good choice.

[roozhou]

DPL II can recover also the center channel and any audio equipment can extract the low frequencies to subwoofer then is a solution ...
if you need a backup in avi format (aac is not supported in avi) with less than 2 GB (to be burn in standard DVD data) to be played by standard standalone players.

For a 3½ hour long movie is a good choice.

You are wrong. AAC is supported in avi. AVI_MUX_GUI can mux aac into avi without any problem.

[tebasuna51]

You are wrong. AAC is supported in avi. AVI_MUX_GUI can mux aac into avi without any problem.

Maybe you can mux the aac but you can't play this avi with standalone players.

To be played by PC you can use mkv without size restrictions.

[Zwitterion]

The back channels of a DPLII-encoded MP3 sound horrible. Bad warbling, etc... Even 320 kbps MP3s are not transparent after they went through a DPL decoder.

[SeeMoreDigital]

Maybe you can mux the aac but you can't play this avi with standalone players.

To be played by PC you can use mkv without size restrictions.You can mux MPEG-4 video with AAC audio into the .MP4 container and play the files perfectly in an NeroDigital certified stand-alone player.

Such players a really affordable nowadays and often come with card readers and USB inputs.

[littleD]

I wonder what happened to Aud-X (http://www.aud-x.com/) project. Site looks like not developed anymore:mad:. Quite pity, cause thanx to aud-x u can have surround mp3 in avi with DolbyPrologicII support at 192kb HQ profile. But as i recall, coding was taking more time than standard mp3, and probably aac gives better quality nowadays.

[tebasuna51]

You can mux MPEG-4 video with AAC audio into the .MP4 container and play the files perfectly in an NeroDigital certified stand-alone player.

I don't know these NeroDigital certified players.

But there are new players with mkv support (Pop Corn, etc), that seems more interesting. Of course a Matroska file with x264 video and aac audio, or flac if we want the best quality, is the next future.

And also store the files in external HDD NTFS with USB 2.0 conexion instead the old DVD, without size problems.

But we are talking about the StickHorsie requirements.

[shon3i]

Personally.... I would have generated a 6Ch AAC-LC audio stream (at 160Kbps) ;)
Why LC-AAC? It's to low bitrate for LC-AAC, i will go definitly with HE-AAC @ 160kbps, aslo from last EBU – TECH 3324 shows that HE-AAC @ 160kbps are tied with AC3@448 and DTS@1536.

[tebasuna51]

I wonder what happened to Aud-X (http://www.aud-x.com/) project. Site looks like not developed anymore:mad:. ...

Yeah, the problem is hardware players compatibility.
If we need a DirectShow filter to play the full surround ...
Also there are multichannel vorbis maybe more eficient than mp3.

[StickHorsie]

DPL II can recover also the center channel and any audio equipment can extract the low frequencies to subwoofer then is a solution ...
if you need a backup in avi format (aac is not supported in avi) with less than 2 GB (to be burn in standard DVD data) to be played by standard standalone players.

For a 3½ hour long movie is a good choice.

I see you're getting exactly why I'm doing what I'm doing. :D

And yes, that was what I wanted to hear: that DPL II will do nicely if you want to spend more MBs on video quality, but don't want to lose the surround effect and still want full compatibility.

:thanks:

Screw your friends, it's your backup, do it however you want!

Having been a professional audio remastering engineer for 22 years (and a bit), I sometimes help out when people have sh*tty audio on their backups (which sometimes happens when they set everything to automatic - I've already seen some pretty weird audio tracks) and the originals aren't available anymore. So far I've had no complaints :p but since I'm rather new to the video editing biz, I wondered if I might have overlooked something important. ;)

And hey, I might win the lottery and surround (pun not intended) myself with speakers one day. :D

The back channels of a DPLII-encoded MP3 sound horrible. Bad warbling, etc... Even 320 kbps MP3s are not transparent after they went through a DPL decoder.

It's logical that reducing any file size should have some side effects... would the "Control rear channel filtering" setting in BeSweet be of help when I'm converting to .wav? (I'm not doing direct AC3 to MP3 conversions, all editing / limting / etc is done manually in the .wav stage.)

[SeeMoreDigital]

I don't know these NeroDigital certified players.

But there are new players with mkv support (Pop Corn, etc), that seems more interesting. Of course a Matroska file with x264 video and aac audio, or flac if we want the best quality, is the next future.Indeed... I have a couple of these types of players. Sadly however they cost several times more than a Nero Digital certified player!

Why LC-AAC? It's to low bitrate for LC-AAC, i will go definitly with HE-AAC @ 160kbps, aslo from last EBU – TECH 3324 shows that HE-AAC @ 160kbps are tied with AC3@448 and DTS@1536.Because AAC-HE is not fully supported in stand-alones.

[littleD]

If we need a DirectShow filter to play the full surround ...


Check this (http://www.aud-x.com/index.php?option=com_content&task=view&id=38&Itemid=1). Anybody tested? I dont have stadnalone dvd player.:mad:

[tebasuna51]

Check this (http://www.aud-x.com/index.php?option=com_content&task=view&id=38&Itemid=1). Anybody tested? I dont have stadnalone dvd player.:mad:

I know this from the beginning (http://forum.doom9.org/showthread.php?p=778095#post778095), and in some test (http://forum.doom9.org/showthread.php?p=837828#post837828)

Works with DS filter in PC players with full surround (quality limited by bitrate) and in standalone players works like DPL II, I think never will be fully supported.

[SeeMoreDigital]

FFdshow is also able to decode Aud-X 6Ch (5.1) MP3 streams, provided you have Audxlib.dll (http://rapidshare.com/files/158716723/audxlib.zip.html) located within the "FFdshow" folder.....