Red Kawa
02-22-2007, 11:41 PM
There’s no shortage of information about the Apple TV out on the web, however even with all this coverage, there are still a lot of unanswered questions regarding the hardware behind the Apple TV and how it plays back video. We’ve been compiling a list of these questions internally as a sort of checklist for when we get a hold of an Apple TV (hopefully) next week. We’ve included this list below and we’ve also added some commentary. Our commentary is PURE speculation at this point. You will have to wait until the Apple TV is out before we get some definitive answers.
What version of HDMI does it support?
Likelihood of 1.1: 100%
Likelihood of 1.2: 99%
Likelihood of 1.2a: 97%
Likelihood of 1.3: 3%
Likelihood of 1.3a: 0%
While HDMI 1.3 support would make the Apple TV future proof, it is quite unnecessary for them to include it as none of the videos on iTunes utilize the advanced features (xvYCC, Deep Color, TrueHD passthrough, DTS-HD) found in version 1.3
HDMI 1.3a was only ratified in November 2006 which is way too late to be included in the Apple TV Hardware design process.
Will it ever support 1080p?
Likelihood of HDMI: 50%
Likelihood of Component: 40%
This depends on the graphics chipset, HDMI chipset and the video scaler chipset.
Is video decoded using an ASIC?
Is video decoded using a combination of software and hardware acceleration?
Likelihood of ASIC: 50%
Likelihood of Software: 50%
With the introduction of HD movie formats, ASICs that can decode MPEG-2/VC-1/H.264 at 1080p resolutions have become readily available. Even the TiVo Series 3, which was released a while back, has one of these chips. So it is quite possible that the Apple TV could have such a chip in it as well.
Most of the Apple rumor sites are report that the Apple TV runs a 1.0 Ghz Pentium-M chip with a nVidia GeForce G72M graphics chipset. With a very highly optimized decoder and lots of hardware acceleration it may be possible to decode 720p H.264 videos on such hardware. There’s absolutely no way a regular PC with those kinds of specs would ever be able to do that though even with the highly optimized CoreAVC decoder.
Will its video decoding abilities be upgradeable?
Likelihood: 75%
This depends on what type of ASIC is used or how powerful the CPU/GPU is and how much breathing room that the Apple TV hardware team left.
What video level of the main profile will it support?
Likelihood of Level 3.1: 100%
Likelihood of Level 4: 20%
Apple already announced 1280x720 H.264 support at 24 fps so that means at least Level 3.1 has to be supported initially. Whether the Apple TV can ever do 1080p will depend on the ASIC or CPU/GPU.
Will it support AAC 5.1 streams?
Likelihood: 99%
You can already find AAC 5.1 streams in some of the HD trailers found on Apple’s site so this is quite likely.
Will it output AAC 5.1 audio in AC-3 5.1?
Does it have a built in Dolby AC-3 encoder?
Will it transcode AAC 5.1 streams to AC-3 5.1 streams on the fly?
Likelihood: 70%
This is quite likely because this is pretty much required for every single a/v receiver built since the beginning to the DVD-era.
Will it output AAC 5.1 audio in PCM 5.1?
Likelihood: 30%
Since you can only transport PCM 5.1 over HDMI and not over an optical connection, and it requires a HDMI decoding receiver this is doubtful.
Will there be no way to get 5.1 sound?
Will it downmix all 5.1 streams to 2.0 streams?
Likelihood: 20%
If this is true then Apple will have really dropped the ball in the audio department.
What version of HDMI does it support?
Likelihood of 1.1: 100%
Likelihood of 1.2: 99%
Likelihood of 1.2a: 97%
Likelihood of 1.3: 3%
Likelihood of 1.3a: 0%
While HDMI 1.3 support would make the Apple TV future proof, it is quite unnecessary for them to include it as none of the videos on iTunes utilize the advanced features (xvYCC, Deep Color, TrueHD passthrough, DTS-HD) found in version 1.3
HDMI 1.3a was only ratified in November 2006 which is way too late to be included in the Apple TV Hardware design process.
Will it ever support 1080p?
Likelihood of HDMI: 50%
Likelihood of Component: 40%
This depends on the graphics chipset, HDMI chipset and the video scaler chipset.
Is video decoded using an ASIC?
Is video decoded using a combination of software and hardware acceleration?
Likelihood of ASIC: 50%
Likelihood of Software: 50%
With the introduction of HD movie formats, ASICs that can decode MPEG-2/VC-1/H.264 at 1080p resolutions have become readily available. Even the TiVo Series 3, which was released a while back, has one of these chips. So it is quite possible that the Apple TV could have such a chip in it as well.
Most of the Apple rumor sites are report that the Apple TV runs a 1.0 Ghz Pentium-M chip with a nVidia GeForce G72M graphics chipset. With a very highly optimized decoder and lots of hardware acceleration it may be possible to decode 720p H.264 videos on such hardware. There’s absolutely no way a regular PC with those kinds of specs would ever be able to do that though even with the highly optimized CoreAVC decoder.
Will its video decoding abilities be upgradeable?
Likelihood: 75%
This depends on what type of ASIC is used or how powerful the CPU/GPU is and how much breathing room that the Apple TV hardware team left.
What video level of the main profile will it support?
Likelihood of Level 3.1: 100%
Likelihood of Level 4: 20%
Apple already announced 1280x720 H.264 support at 24 fps so that means at least Level 3.1 has to be supported initially. Whether the Apple TV can ever do 1080p will depend on the ASIC or CPU/GPU.
Will it support AAC 5.1 streams?
Likelihood: 99%
You can already find AAC 5.1 streams in some of the HD trailers found on Apple’s site so this is quite likely.
Will it output AAC 5.1 audio in AC-3 5.1?
Does it have a built in Dolby AC-3 encoder?
Will it transcode AAC 5.1 streams to AC-3 5.1 streams on the fly?
Likelihood: 70%
This is quite likely because this is pretty much required for every single a/v receiver built since the beginning to the DVD-era.
Will it output AAC 5.1 audio in PCM 5.1?
Likelihood: 30%
Since you can only transport PCM 5.1 over HDMI and not over an optical connection, and it requires a HDMI decoding receiver this is doubtful.
Will there be no way to get 5.1 sound?
Will it downmix all 5.1 streams to 2.0 streams?
Likelihood: 20%
If this is true then Apple will have really dropped the ball in the audio department.