-princealfie
I believe that was stopped because they were successful in doing it to the MPEG2 codec.
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Apple TV and 5.1 support - some definitive answers
- Thread starter maurj
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-princealfie
I believe that was stopped because they were successful in doing it to the MPEG2 codec.
-sycho
Oh boy. Umm, let's just say I'm running pretty near an 'ideal' system.
All HDMI (except the DVD player, it's Component)
DVR,TV, and that DVD player go to a Denon AVR-4306, which, in turn HDMI to the Sharp Aquos.
Ok, give a HD trailer with a 5.1 AAC track a try on that.
That is called Pro Logic II
300 should work
-sycho
I'm sorry if I haven't explored much in that menu, but when I did pay 300, it sure didn't look HD to me. How can I tell what it's supposed to be HD 5.1 and not?
How about the newly released "28 Weeks Later" trailer:
http://www.apple.com/trailers/fox_atomic/28weekslater/
Just watched the 720p version and checked the encoding settings:
"AAC, 5.1 (C L R Ls Rs LFE), 48.000 kHz"
http://www.apple.com/trailers/fox_atomic/28weekslater/
Just watched the 720p version and checked the encoding settings:
"AAC, 5.1 (C L R Ls Rs LFE), 48.000 kHz"
You have to download the HD 720P trailer and add it to your iTunes, then play it on the AppleTV
to quote the author:
If he doesn't know the difference between a matrixed (Dolby Surround) and discrete (5.1 dolby digital or dts) then he should not be writing about it.
and, now, i will point you to this post:
http://images.apple.com/movies/wb/300/300-tlr2_h720p.mov
http://images.apple.com/movies/wb/300/300-tlr1_h720p.mov
My original post was saying if you hack the ?TV and add all of the necessary codecs to the quicktime folder as you do now in your mac won't it play AC-3 audio, I don't have one yet to check but if you find all of the codecs for quicktime that let your mac do it then the ?TV should right or am I missing something???
Tested this last night with analog cable and optical cable (And added the 720P trailer through itunes). The receiver picks up the sound as PCM. As previously confirmed, the Apple TV does NOT output surround through either audio connection. Unfortunately.
That could mean TWO things, though...
1. The trailer has no pass-through AC-3.
2. The so-called pass-through AC-3 is actually in an MPEG-4 container as multichannel AAC and needs to be transcoded to AC-3.
The thing you need to realize is that AC-3 is a proprietary codec of Dolby Laboratories. In order for Apple to give it functionality they need to use a licensed decoder or make a decoder that Dolby Labs will license.
This is actually GOOD because you don't want a decoder that cannot guarantee the fidelity standards set for AC-3 by Dolby Labs. There are plenty of licensed AC-3 encoders and decoders, and it's not out of reach for Apple to implement something like Dolby Digital Live to transcode multichannel AAC to AC-3.
But of course it depends on the source actually possessing multichannel AAC.
For the record, I have not seen a single blog entry, review, or other statement anywhere from a user who can verify that AC-3 pass through has actually ever worked with any Dolby Digital decoder.
The trailer definitely uses 5.1 AAC audio, and does not utilize AC3. I did notice this post:
Then if it doesn't hit the receiver as AC-3, either AppleTV has no transcoder or has a transcoder (e.g. Dolby Digital Live) which is not enabled yet.
As for the comments about DTS WAV. DTS is a different coding schema from Dolby Digital. In its theatrical implementation, DTS is fundamentally an ADPCM bitstream. DTS in DVD's however is a perceptual coding system based on ADPCM. In this sense, a DTS stream in WAV, which is basically a container for PCM, is probably detectable by a DTS decoder but I'm curious about any metadata that might be lost when converting DTS to DTS WAV.
Dolby Digital is a different matter because it relies on a number of metadata parameters which extend its dynamic range while minimizing bitrate requirements to produce equivalent or greater fidelity than DTS (despite what the audiophiles seem to think).
I'd personally be content if it just passed the AC-3 stream, or any stream for that matter, through to my receiver. I really don't think it's Apple TV's job to decode Dolby Digital. My receiver would do it much better anyway.
If Apple doesn't implement true multi-channel audio in some form, this one's out for me. Although, I'd bet Apple is working on adding it.
If Apple doesn't implement true multi-channel audio in some form, this one's out for me. Although, I'd bet Apple is working on adding it.
-QuarterSwede
Agreed. If it were it would likely be able to drive the speakers directly, but then, that's not the intent of the device. Oh, and that'd add a $$load of $$.
-QuarterSwede
The chip is in there, the ports are certified to standards, I think its just a matter of time. I think the holdup is that there isn't any legal content available to the
TV that'd use it...... right? Can't think of any besides the hi-def trailers (which look GREAT off the
TV BTW)
OK, so the AppleTV is (for now) limited to 2.0 PCM via HDMI, and will always be limited to 2.0 PCM over the optical. Again, like I have said in several threads, although it would be possible to have an Dolby Digital or dts output for the AppleTV, it would only work for pre-encoded content, non of which is avalible on iTunes.
I've successfully gotten AppleTV to pass DTS and Dolby Digital 5.1 via optical to my receiver with WAV files from http://www.diatonis.com/downloads_dts_ac3.html. Just load them or stream with iTunes.
Note that my ATV is off the shelf... unhacked.
Now that we know it's possible...
Wonder if I can rip my dvds and then encode them using VirtualDub (Winblows only http://www.free-codecs.com/download/VirtualDub.htm) to get 5.1. Need to find a Windows machine to test.
5.1 Working on AppleTV - Dolby Digital
First off, this will allow you to play on a DD receiver ONLY. If you try to play on your laptop, you get static... so that said.
1) Demux with MPEG Streamclip to M2V and AC3.
2) Copy AC3 to windows machine to use BeSweet to convert to DD-Wav. (if there is an OS X alternative, please let me know.
3) Copy DD-Wav back onto Mac.
4) Open m2v in Quicktime Pro.
5) Open dd-wav in quicktime pro, then add to the m2v movie.
6) Export to Quicktime. h.264 (i used one pass to save time @2400kbps) w/ Apple Lossless 44.1 stereo w/o streaming box clicked.
7) Add to iTunes Library
Play on AppleTV with glorious 5.1 DD!
That's it.
Here's the THX intro from Monster's Inc.
http://www.crackedpolystyrene.com/thx.mov
First off, this will allow you to play on a DD receiver ONLY. If you try to play on your laptop, you get static... so that said.
1) Demux with MPEG Streamclip to M2V and AC3.
2) Copy AC3 to windows machine to use BeSweet to convert to DD-Wav. (if there is an OS X alternative, please let me know.
3) Copy DD-Wav back onto Mac.
4) Open m2v in Quicktime Pro.
5) Open dd-wav in quicktime pro, then add to the m2v movie.
6) Export to Quicktime. h.264 (i used one pass to save time @2400kbps) w/ Apple Lossless 44.1 stereo w/o streaming box clicked.
7) Add to iTunes Library
Play on AppleTV with glorious 5.1 DD!
That's it.
Here's the THX intro from Monster's Inc.
http://www.crackedpolystyrene.com/thx.mov
you can only get the 5.1 if you use the optical port?
I am getting a new 5.1 Sound System in the next week that has 2 optical inputs I will test a DVD in my DVD player and then rip the DVD (using handbrake) with 5.1 encoding then report my results
I am getting a new 5.1 Sound System in the next week that has 2 optical inputs I will test a DVD in my DVD player and then rip the DVD (using handbrake) with 5.1 encoding then report my results
Handbrake won't get you DD yet
They are working on handbrake getting 5.1. It's not there yet. Try my tutorial and/or file above. And yes, you need optical. If you d/l my file and it sounds like static, that's cause it's a dolby signal. When you play it on your AppleTV through the optical to a receiver that understands DD, then it will play correctly with 5.1.
They are working on handbrake getting 5.1. It's not there yet. Try my tutorial and/or file above. And yes, you need optical. If you d/l my file and it sounds like static, that's cause it's a dolby signal. When you play it on your AppleTV through the optical to a receiver that understands DD, then it will play correctly with 5.1.