5.1 to Stereo ... Mac vs AppleTV

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dkeel
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5.1 to Stereo ... Mac vs AppleTV

Postby dkeel » Mon Jan 12, 2009 9:03 am

OK - perhaps this is a stupid question .. but whether it is or it isn't ... I still don't know the answer and really would love some help!

I have around 800+ movies that I have ripped from DVD's ... mainly using Visual Hub and ripping to AppleTV 5.1 (so only a 5.1 soundtrack on 99% of them -no stereo etc). I have 2 appleTV's - and stream the movies to them. No problems with the AppleTV connected to my Home Cinema system - the 5.1 streams through to my amp via optical and all works really well. BUT - not so successful with the AppleTV that is connected to a standard stereo LCD telly in my daughter's bedroom. 99% of the movies appear to have no sound (but older stereo movies and mp3 tracks play just fine).

OK - here is the problem (the way I see it) - if I want to play AC3/5.1 movies on my Mac laptop (for example) all I have to do is download and install Perian and the sound works great! Perian appears to change the 5.1 audio stream into 2 channel stereo. Great!! Absolutely wonderful piece of software - invaluable to most Mac owners.
BUT - if I install Perian onto the hacked AppleTV then since there is no control panel then I cannot set it to make the Audio output "stereo". And every AppleTV post seems to be about people struggling to get the 5.1 audio out of the AppleTV onto their systems ... wheras I kind of want the opposite - I want to be able to use Perian to convert (I think) the 5.1 audio to stereo for output from the AppleTV via either the HDMI or stereo outputs.

Really really hope somebody can help me with this - my next resort is going to have to be that I buy some sort of old amp and speakers with 5.1 optical input .. which is overkill for a bedroom I think.

Thanks in anticipation to anyone who can help!

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Mon Jan 12, 2009 1:25 pm

The good news is, it isn't something you did wrong, per say. The bad news is it is something Apple did wrong, and thus it is difficult to fix. I responded to nearly the same question on the ATV hacking site a few weeks ago: http://forum.awkwardtv.org/viewtopic.php?f=2&t=2291

Basically, your options boil down to:
  • Add a stereo AAC track to the movie files
  • Try changing the fourcc (dumpster from http://developer.apple.com/quicktime/qu ... tro/tools/) of the AC-3 track to 0x6D732000. This means you will have to use the AC3 hack on the home cinema system, but it will fallback to decoding the audio on your daughter's. This is assuming the hack works on your Home Cinema decoder. Actually, now that I think of it, dumpster won't be very good at changing this. Maybe a hex editor will serve you. The AC-3 track currently uses the four-cc 'ac-3'. The hex translates to 'ms \0' (that's a space and a null character).
  • Have your daughter use a playback method that doesn't involve QuickTime on her ATV.
  • Get a decoder for your daughter (The one I have is made by Sony and cost $150 at Fry's, included 5 speakers and sub. Not a bad entry system)
  • Give up.

You may want to reference the bug ID that I mentioned on the awkward forums and report it yourself, but I have absolutely no confidence that Apple will ever fix it.

dkeel
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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby dkeel » Mon Jan 12, 2009 4:44 pm

Thanks for this input - and it was me who posted on the AwkwardTV site - with a slightly different version of the same problem and, to be fully honest, I don't think that I really understood your response. I can follow out the sort of step by step Terminal instructions that are published for some solutions and hacks .. but when I have to use my brain then I start to struggle!!!! Ive responded to your suggestions one by one

1) I can't really afford the time to add a stereo track to all of my ripped movies (ie re-rip them - this would take months and would also send my data requirements even higher!) - currently at around 3 tb!

2) Can't really understand this proposal from you (ie I have to start using my brain) - should I assume that I can probably get some sort of hex editor and go into each movie (obviously I would trial it on a few first) and change a setting re the audio track that is called "fourcc" and will probably be set as "ac-3" (or in a hex editor will display as "ms \0") to " 0x6D732000" and then change the set up on the AppleTV connected to my Home Cinema system to accomodate this (Onkyo 606 amp - fingers crossed!). I am guessing that you are proposing that this should force Perian to decode the 5.1 to stereo and output this via either the HDMI or the phono audio out?

3) I think that by this you are suggesting that I get the AppleTV set up with either XBMC or Boxee fronting it and that this will allow the 5.1 movies to output stereo from the AppleTV? Can Boxee and XBMC do this?

4) Currently scouring the cupboards at home for old hifi kit that might fit the bill - if not then it does look as though a £100 - £150 spend will be necessary

5) almost ready to give up - but not really in my nature!!!!

I'd appreciate your confirmation that I have understood your response - and would also, if you have the time, like some help in understanding why Perian is great for getting my (essentially) stereo laptop to play 5.1 movies - wheras it seems to do something totally different when installed on the AppleTV?
Thanks again for your response on both this and the Awkward TV site - I was a bit ashamed that I didn't understand your Awkward response and so thought that I would try the Perian site in the hope that I could get an easier fix?!
Regards

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Mon Jan 12, 2009 5:46 pm

dkeel wrote:Thanks for this input - and it was me who posted on the AwkwardTV site - with a slightly different version of the same problem

I was wondering if there was someone else with a large library of AC3 audio content that he wanted his daughter to be able to play.

dkeel wrote:1) I can't really afford the time to add a stereo track to all of my ripped movies (ie re-rip them - this would take months and would also send my data requirements even higher!) - currently at around 3 tb!

While the disk usage will increase, I was not talking about re-ripping. Here I was thinking of opening up the video file in QuickTime Player, saving the audio as AAC, opening the saved AAC track, adding to the original movie, save. The original video/AC3 audio tracks remain, only a new AAC track was added. This is annoying manual work though.

dkeel wrote:2) Can't really understand this proposal from you (ie I have to start using my brain) - should I assume that I can probably get some sort of hex editor and go into each movie (obviously I would trial it on a few first) and change a setting re the audio track that is called "fourcc" and will probably be set as "ac-3" (or in a hex editor will display as "ms \0") to " 0x6D732000" and then change the set up on the AppleTV connected to my Home Cinema system to accomodate this (Onkyo 606 amp - fingers crossed!). I am guessing that you are proposing that this should force Perian to decode the 5.1 to stereo and output this via either the HDMI or the phono audio out?

This is not for the faint of heart in the least. The movie file will have the string 'ac-3' within it at a few points. If this is changed 'ms \0' (which is 0x6D732000 in hex), then Apple's code no longer handles the AC3, but Perian (really A52Codec) takes over. The audio sample rate needs to be correct still, and the decoder must be able to handle it, but if this works on your decoder, then it may be the easiest method. Maybe I could write a quick QTKit tool that does this? Instructions to Perian's AC3 passthrough are here: http://www.cod3r.com/2008/02/the-correc ... quicktime/

dkeel wrote:3) I think that by this you are suggesting that I get the AppleTV set up with either XBMC or Boxee fronting it and that this will allow the 5.1 movies to output stereo from the AppleTV? Can Boxee and XBMC do this?

Correct, though I heard the two are a bit slow for browsing. NitoTV can use mplayer as well as QT, so it qualifies as well.

dkeel wrote:I'd appreciate your confirmation that I have understood your response - and would also, if you have the time, like some help in understanding why Perian is great for getting my (essentially) stereo laptop to play 5.1 movies - wheras it seems to do something totally different when installed on the AppleTV?

Because the AppleTV is a piece of junk! Apple violated their own QuickTime documentation to make passthrough work at all, and they did it badly. Not only is it incapable of decoding AC3, it is also incapable of falling back to a software component if one is available, and it is also incapable of playing AC3 frames which are packetized differently. I think this, along with other actions, pretty clearly states that the ATV, in Apple's mind, is for nothing else than to sell overpriced and degraded quality iTunes movies (I may be a bit too harsh here, but frankly I see purchases of movies from iTMS as a waste of money).

dkeel wrote:thought that I would try the Perian site in the hope that I could get an easier fix?!

Sorry, the ATV is just badly broken. Apple made it work for their content, and essentially turned a blind eye to anyone wanting to use their ATV for anything more.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Mon Jan 12, 2009 7:01 pm

gbooker wrote:Maybe I could write a quick QTKit tool that does this?

http://www.cod3r.com/ChangeFourCC.zip

It's command line, so you need to use terminal. It's first argument is the original mov/m4v/whatever file, and the second is where to save the new file. It saves a reference movie, but it should be sufficient for testing. Requires Leopard to run. Hope this helps.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby dkeel » Tue Jan 13, 2009 8:30 am

WOW - first of all thanks so much for your wonderfully thought through and patient response. My understanding of (and doubts about) the AppleTV have grown more in the past 24 hours than at any time in the past year or so! Thanks loads - first, for taking the time and second for persevering with my lack of in-depth knowledge.
Progress so far - I have used the ChangeFourCC routine "./ChangeFourCC movie.mov movie4cc.mov" from terminal and it certainly does appear to work correctly.... and as you have suggested, it makes a Reference Movie. Unfortunately the AppleTV can't sync Reference Movies and so I had to load the movie4cc into Quicktime and save as SelfContained. This now syncs BUT whilst my amp will see 5.1 DD audio in "movie", it can't sense any audio in "movie4ccc". That's all I had time for last night - and will now be trying out the audio on both movies via the AppleTV in my daughters room. If that unit/tv combination can play the audio (I recognise that I'll have to twiddle with the settings in things such as Sapphire/Perian etc.) then I will revert to working on getting the AppleTV and my Onkyo amp working with the 4cc movies (again by tweaking some of the application settings). So - thanks to you - it does feel as though a bit of progress has been made... but I guess that the next few days of experiments will confirm this?!
Thanks so much for all of your help - will keep you posted. Also plan to fiddle with mPlayer on my daughters AppleTV - but since I am even more useless when it comes to networking (and I would have to point the app at my Drobo full of movies) then I am even less confident.
Cheers

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Tue Jan 13, 2009 1:36 pm

I made it save a reference movie because I didn't want to overwrite the original, it's fast, it is easy to generate a self-contained movie from it. Since this is mostly for testing purposes anyway, it fits the bill here.

Your main ATV will need Perian (specifically, the A52Codec) installed before it will play any audio. Once installed (and the Finder interface is restarted), then the output sample rate of the ATV need to be changed to 48KHz (since most DVD audio is 48KHz). At this point, if passthrough is enabled, and you hear a "helicopter" noise, then it's likely your amp will not work with the passthrough hack.

I think I recall someone with an Onkyo amp reporting that the passthrough hack does not work, but it may be specific to their model. My dad has one by Pioneer, and it plays a click for a fraction of a second, and goes silent. Until Apple exposes a real method for making AC3 passthrough available through QuickTime, this is the best that can be done (I've asked for one, and my ticket got marked as duplicate nearly a year ago).

Unfortunately, most people have found it easier to completely hack their ATVs, and use a NAS (or computer with sharing on) to share the files, and entirely use third party plugins.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Tue Jan 13, 2009 4:06 pm

gbooker wrote:then the output sample rate of the ATV need to be changed to 48KHz

I realized this can be difficult on the ATV, far more than on the mac. So, I wrote a quick tool that should do the job: http://www.cod3r.com/ChangeSampleRate.zip

Execute

Code: Select all

ChangeSampleRate 48000
on the ATV, and it will change the sample rate to 48KHz.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby dkeel » Sun Jan 18, 2009 2:26 pm

Hi - first of all, yet again, many many thanks for your help. Sorry that I haven't got back to you sooner... today has been the first time that I have had some time to get back to work on my AppleTV challenges!
OK - I'll spell out what I have done for the benefit of anyone who is following this thread and who, like me, likes to have things spelt out!
I believe that I now have 2 possible solutions...
The first is using QuickTime Pro to make another audio track (AAC) from the AC3 and then adding it back into the original movie (MOV)file:

Open Movie - Show Movie Properties
Select the AC3 soundtrack and Extract ... save as m4v (takes around 5-10 minutes)
Open the saved m4v track and select all/copy
Edit .. add to movie
And in movie Properties you'll see that the Movie now has two soundtracks ... one is AAC and the other is AC3
Save as self contained movie

I can confirm that this works - my AppleTV connected to the Onkyo HiFi 5.1 amp sees the AC3 5.1 track on the optical out and plays it fine.. the AppleTV connected to a stereo tv via HDMI sees the AAC Stereo track and passes it to the telly via the HDMI lead.
File size expansion is not as great as I though it would be ... a 3.55 gig 720p 5.1 file expanded to only 3.61g - not really an issue
The whole process probably took 15 minutes from start to finish ..but perhaps this can be scripted or set up via Automator... I've got a bit of time next week to check this out!

The ChangeFourCC also appears to work ... in that the movie audio track appears to become "unrecognised" by the AppleTV and so it is passed to Perian,which then plays it as Stereo and passes it via the HDMI to the stereo tv. The only issue here is that my Onkyo amp seems to dislike this output from the AppleTV that it is attached to and so I have had to fiddle around with your app (Change Sample Rate) and settings via Perian and Sapphire etc on the AppleTV - as yet no success - but I fully realised that this could be an issue with the Onkyo amp - and even if I can get it working now, it could still prove to be a problem with any future amp that I may upgrade the Onkyo to???? I intend to keep on fiddling (and keep notes of what I do) before I give up!

Soooooo - I need to give this a bit more thought .... Either process is going to take 15-30 minutes per movie, the "ChangeFourCC" process will be a bit quicker and will not have any overhead in terms of size but may give problems if I change my amp in the future. The "extra AAC audio" process will take a little longer and will probably add 1 - 2% to my data requirements (probably a total of around 50 gig in total I guess).

Thanks so much for your help - please don't see my delay in responding as any kind of bad manners _ I wanted to make sure that I could respond sensibly before I gave feedback. I have gone into more detail above in case anyone has the same issues as I have had and stumbles on this thread as a solution (something that I would have been overjoyed to find).

Will let you know what decision I make .. and if I do manage to get a script or an automator process up and running (if this is the route that I go down) then I'll put it up for download.

Fingers crossed for now and thanks yet again

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby dkeel » Sun Jan 18, 2009 5:26 pm

Me again... noticed something "interesting" that may have some relevance to this thread (and have googled and can't find any info on this). A lot of my movies have (as discussed previously in this thread) AC3 5.1 audio tracks in them. If I use QTPro and look at the properties of the audio and then look at the Audio Settings I notice that on the majority of the movies the channels are simply set to 6 "Mono" channels (although there are pull down menus that would allow me to change this... very dangerous I guess?) wheras a small number of my movies that also contain AC3 have the channels set as Left/Right/Center/LFE Screen/LFE Surround/Right Surround. This seems to apply to both M4V and MOV movies.
Strangely - if I use Spotlight to search through my movie collection and show movies where channel count = 6 then it only lists those that have the 6 channels defined as Left/Right etc ... I have to set channel count=1 to get it to show the ones with 6 mono channels!? Strange behaviour?
(I wanted to do some sort of listing of my movies to work out which ones only contained an AC3 track and thought that this could be a way of doing it!?
Anyone know anything about this ... and which is "right" - 6 x mono or 6 "labelled" channels?

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Sun Jan 18, 2009 7:59 pm

dkeel wrote:Anyone know anything about this ... and which is "right" - 6 x mono or 6 "labelled" channels?

The layout is the layout that the decoder uses, since QuickTime is completely incapable of telling the decoder what order to use, which is made worse by the fact that QuickTime's AC3 file importer uses the wrong order (rdar 5799879). The only multichannel AC3 decoder I know of in QuickTime is the A52Codec (included in Perian) which uses layout kAudioChannelLayoutTag_ITU_3_2_1 otherwise known as kAudioChannelLayoutTag_MPEG_5_1_A. The channel order is: L R C LFE Ls Rs (channels which are not present are skiped, so a 4.1 layout without the center channel would be L R LFE Ls Rs).

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby dkeel » Mon Jan 19, 2009 2:53 pm

Hi. Me again. Have hit another speed-bump and I am hoping that you may be able to help.
I decided that I would add an AAC stereo track to all of my movies using the process that I outlined above:

Open Movie - Show Movie Properties
Select the AC3 soundtrack and Extract ... save as m4v (takes around 5-10 minutes)
Open the saved m4v track and select all/copy
Edit .. add to movie
And in movie Properties you'll see that the Movie now has two soundtracks ... one is AAC and the other is AC3
Save as self contained movie

Trouble is, I tried to go through the same process again on my Mac at the office (so that I could better document the process for when I work out an automator or script method) and instead of the AC3 soundtrack saving as an M4v (stereo AAC) it has saved as an MOV with the 6 mono channels still in tact!

Thought it might be that I didn't have the MPEG-2 Component for QuickTime installed - but installed it and the results are the same. Any ideas on what I might be doing wrong this time .. yesterday the AC3 seemed to save as M4V as default.. but not today?! Sorry to be a pain again - but could do with a bit more help! Thanks in anticipation

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Mon Jan 19, 2009 3:26 pm

dkeel wrote:Select the AC3 soundtrack and Extract ... save as m4v (takes around 5-10 minutes)
Open the saved m4v track and select all/copy

There's no advantage or disadvantage of using m4v as the file format to store the AAC audio instead of mov. The m4v file format is just a special case of the mov file format.

For creating the AAC track, it's easiest to open the original movie (correct the channel layout of the AC3 if it needs to be corrected), Export the movie as a QuickTime Movie selecting only audio, set it to AAC, 2 channel, "Recommended" sample rate, and save.

BTW, the 6 mono channels could be a result of Earlier versions of Handbrake which didn't set a channel layout.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby dkeel » Mon Jan 19, 2009 5:11 pm

Great - thanks for this. Done some tests and it works fine .. and the information in the QT file does appear to be accesible and scriptable ... so fingers crossed for an automated or semi automated solution.
Most of my movies were ripped via Visual Hub (RIP) as AppleTV 5.1/two pass/go nuts quality - but perhaps it had the same issues as Handbrake. They do sound OK when played via 5.1 - but the vast majority all simply have 6 unallocated mono tracks. I could probably do something to allocate them all correctly (even if I do it by hand, say, a dozen a day!) but would this be worthwhile.. I would be guessing which track was which - as it is I let the amp guess and it seems to do OK! (or would I simply label each track assuming that 1=Left/2=Right/3=Center/4=LFE Screen/5=Left Surround/6=Right Surround?)
Thanks yet again for all of your help so far - I can only hope that somebody else somewhere in the world has the same sort of problem and is also benefiting from your valuable input and advice as well as me!
Regards

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Mon Jan 19, 2009 8:04 pm

dkeel wrote:Most of my movies were ripped via Visual Hub (RIP) as AppleTV 5.1/two pass/go nuts quality - but perhaps it had the same issues as Handbrake.

Likely so. Since Apple's video files contained both AC3 and AAC audio tracks, they didn't bother to include the channel layout information in the AC3 track. Since they didn't make any AC3 decoder for the Mac, they assumed that no such thing does, nor will ever, exist, therefor the need for a channel layout is moot. Ripping programs simply emulated the format Apple used, perpetuating Apple's error.

The problem with the missing layout is solely an issue within QuickTime, and an issue when you make your AAC tracks. The layout comes into play during the decode process, where QuickTime gives the compressed data to the codec, and the codec gives back the uncompressed data in 6 discrete channels. If QuickTime doesn't know the correct channel layout (order), it assumes all 6 channels are mono channels, as you saw, and adds them all together into a single mono track, which is not what you want. This is not an issue with passthrough, because the raw bitstream is sent to the receiver, and it does the decoding, not QuickTime.

Apple seems determined to screw up AC3 at every stage. Nearly every change they have made just makes things worse, and I'm getting tired of working around their mistakes. Only once did they make things better, and that was to correct some of the errors they made in a previous version (not all BTW). I'm nearly to the point of making my next HTPC (Home Theater PC) to be not a mac. The day that happens, my Perian and A52Codec development will likely cease. Apple doesn't seem to understand that if they did things right, they could capture this market, but instead seems to think that everyone wants to buy crap from iTMS, which is going to decline with the current economy.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby Trevize » Tue Jan 20, 2009 9:03 am

gbooker, apple includes a channel layout in their mp4, and it's the standard one for ac-3 in mp4 as defined by the ETSI specifications. And HandBrake has always included a channel layout for ac3 too.
The only problem I see here (other than appletv audio selection being totally broken in 2.3) is that there is apparently no way of telling coreaudio the preferred channel layout.
Btw, does anyone know what's inside the magic cookie passed to the a52codec?

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby dkeel » Tue Jan 20, 2009 10:59 am

Hmmmm - I'm really going to hesitate before I press "Submit" on this comment. gbooker you have been incredible and I have learnt more about movie formats etc in the past week than I have during the past few years! I really wish that I had consulted with you BEFORE I decided to RIP all of my DVD's for the AppleTV ... not afterwards. It has taken me several months to complete the project and I now feel that I am trying to rescue all the ripped movies from Apple rather than make the best use of them. If you decided to walk away from Perian then the Mac community would be up the creek without a paddle as I guess that Apple do not see any mileage in putting their handling of 5.1 audio back on track - which is such arrogance (and, in many cases, is what is attractive about Apple - but in this case, stinks!).
What I can tell you is this - my colleague and I have been Mac fans since day 1 - believe it or not I still have issue #1 of Mac User magazine in my desk drawer! We both bought iPods, AppleTV's, iPhones (even that handheld thingy that they brought out around around 10 - 15 years ago) .. and just about every new Mac - as soon as they were available - BUT - my colleague has recently given up on his AppleTV (hence the reason why I have 2) and has bought a Dell PC and an Xbox - and has installed WIndows 7 along with the Media Centre stuff that it comes with - and he is raving about it. Every single thing that I would want to do with my AppleTV and Mac seems to be able to be easily doable .. and he can even do stuff and play formats that neither of us ever thought we'd need to do (eg play HD MKV and VIDEO-TS with ease, split screen comparison of before/after change of image handling etc etc). He has now decided that he will run a full home automation system from the same PC .. and has fixed his Mac to boot permanently into Windows!!!!
It's a worrying time - everyone is talking about the credit crunch - but in the Mac world there does also seem to be an impending credibility-crunch.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Tue Jan 20, 2009 3:11 pm

Trevize wrote:apple includes a channel layout in their mp4

No they didn't; I examined the raw hex of the file. They may now, but they didn't in the past.

Trevize wrote:And HandBrake has always included a channel layout for ac3 too.

Wrong again. If they had, there would be no reason for this post: http://forum.handbrake.fr/viewtopic.php ... 6&start=25 As is evident from their posts, they simply copied the audio specification as was in Apple's files, without understanding it.

Trevize wrote:standard one for ac-3 in mp4 as defined by the ETSI specifications

Citation?

Trevize wrote:The only problem I see here (other than appletv audio selection being totally broken in 2.3) is that there is apparently no way of telling coreaudio the preferred channel layout.

That's only one problem. There are several more.

Trevize wrote:Btw, does anyone know what's inside the magic cookie passed to the a52codec?

Undocumented, which is one such problem I eluded to above. There are calls to set a channel layout and get a channel layout in a CA component, but the setter is never called, and the getter's result is ignored.

The A52Codec uses the channel layout as defined by Core Audio's documentation, which is appropriate as it is a Core Audio component. The documentation explicitly states the channel layout order, and Apple seems to be ignoring their own documentation.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby gbooker » Tue Jan 20, 2009 3:38 pm

dkeel wrote:We both bought iPods, AppleTV's, iPhones (even that handheld thingy that they brought out around around 10 - 15 years ago) .. and just about every new Mac - as soon as they were available - BUT - my colleague has recently given up on his AppleTV (hence the reason why I have 2) and has bought a Dell PC and an Xbox - and has installed WIndows 7 along with the Media Centre stuff that it comes with - and he is raving about it

I'm in much the same boat as your friend, but I haven't gone as far as getting the PC. The simple fact is that Frontrow/ATV is a poor substitute for what else is out there. The sad thing is, I was happy with the way things were, but Apple seems insistent on breaking things that I used, making it worse.

dkeel wrote:It's a worrying time - everyone is talking about the credit crunch - but in the Mac world there does also seem to be an impending credibility-crunch.

I was intending to limit my comments to movies and TV shows on iTMS, as that is a luxury. The music there is still decently priced, but the TV shows and Movies are not. In addition they are lower quality, thus making the convenience their only advantage. In a troubled economy, people will not pay for convenience, but they will still pay for superior products. This is relevant because Apple seems to only work on Frontrow/ATV to sell TV shows and movies from iTMS.

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Re: 5.1 to Stereo ... Mac vs AppleTV

Postby Trevize » Wed Jan 21, 2009 7:23 pm

http://pda.etsi.org/pda/home.asp?wki_id ... 8EBA7EAy,5 the section about ac-3 inside mp4.

Yeah it was an hack, but the hack was just a standard sample description with a dac3 atom. And inside the dac3 the channel layout as in the new ETSI specification.


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