Inside OS X 10.8 Mountain Lion GM: AirPlay Mirroring
AirPlay, Apple's wireless audio and video distribution system, gets an update in OS X Mountain Lion, offering modern Macs with compatible hardware the ability to wirelessly mirror the screen to an Apple TV-attached HDTV display.
AirPlay, originally named AirTunes when Apple debuted it in 2004 as a way to wirelessly stream audio from iTunes to speakers connected to the AirPort Express base station, had its name changed by Steve Jobs in 2010 after the technology was expanded to include video and photo streaming to the then-new, $99 iOS-based Apple TV.
While iTunes currently has the ability to stream both audio and video playback to Apple TV, OS X can't deliver audio or video from other apps. Additionally, because AirPlay involves encryption of streamed data, it's not easy for third party developers to send data to AirPlay devices.
New AirPlay Mirroring
All that is changing in Mountain Lion. The most obvious benefit is that hardware-compliant Macs can now do the same AirPlay Mirroring trick as last year's new iOS devices (iPhone 4S and iPad 2 or newer): anything on the screen can be mirrored to an Apple TV-connected display.
As with iOS devices, Macs need special hardware to support AirPlay Mirroring. It doesn't work on the Mid 2010 MacBook Pro, for example, but does work on early 2011 MacBook Pros, as well as mid 2011 or newer MacBook Air, iMac or Mac mini systems.
These systems are the oldest machines capable of supporting AirPlay Mirroring because they are the first to deliver dedicated hardware encoding for H.264. Without a CPU capable of crunching this task using specialized hardware, earlier Macs simply can't transmit video fast enough without a lot of heat and screaming fans.
Older Macs can already send video from iTunes to Apple TV via AirPlay, but they stop local playback while doing this. Mirroring requires the system to produce two video images, one driving the local display and one to be wirelessly delivered to the external screen.
AirPlay doesn't just relay video from the computer (or iOS device) to Apple TV. It scales down the video to fit on an HDTV resolution, and has to convert the colorspace from the computer's RGB to the native YUV that televisions use. Both tasks require a lot of processing resources, so without the extra hardware available on newer Macs, mirroring isn't possible.
The new Displays pane
Using AirPlay Mirroring on supported Macs with Mountain Lion is very easy: simply pull down the AirPlay menu and select the local Apple TV you want to mirror your display on. The options are populated via Bonjour, just as they currently are within iTunes. This quite a lot more obvious and discoverable than on the iPad, where you have to double click on the Home button and swipe to the right to find AirPlay controls (below).
The default Menu Bar options for Displays now focuses on AirPlay options, rather than the old fashioned "detect displays" and manually setting a resolution. Below, the simpler menu of Mountain Lion (right) compared to today's Lion (left). On Macs that don't support AirPlay Mirroring, this menu simply offers only to open the Displays pane in System Preferences.
Apple has also updated the Displays pane in System Preferences in Mountain Lion, even for Macs too old to support AirPlay Mirroring. Rather the offering a selection of resolutions (as today's Lion does, below top), Displays now simply defaults to the resolution "Best for built-in display," although you can manually select a non-standard resolution by clicking Scaled.
Using AirPlay Mirroring on supported Macs
You can readily identify a Mac that supports AirPlay Mirroring because it gets the AirPlay icon in the Menu Bar (and its drop down options are different too).
Once AirPlay Mirroring is initiated with a specific Apple TV unit from the Menu Bar, the Displays configuration automatically changes to the resolution "Best for AirPlay," with an option to turn on Overscan correction (usually only necessary if you're using an older CRT television; most modern flat panel displays won't cut of portions of the display because of overscan). Note that brightness controls only have an effect on the built in display.
You can manually select a different resolution from Displays, or select the resolution you want to mirror from the AirPlay Menu Bar pulldown, picking either This Mac or the name of the Apple TV you're mirroring the display to from the "Match Desktop Size To:" options.
Managing multiple displays with AirPlay Mirroring
But wait, that's not all. You can still initiate AirPlay Mirroring while connected to a secondary display. Under Mountain Lion, connecting to an external monitor works virtually the same, apart from the fact that the system, by default, pics the resolution for you. Plugged directly to my HDTV via an HDMI cable, the Displays pane for each of the two displays picks a "best for display" resolution, although either can be scaled.
The built in display supplies an option to adjust brightness (above) while the HDTV pane (below) presents options to rotate the display in 90 degree increments, set a refresh rate, and configure underscan (which creates a black margin around the image on your television to prevent elements close to the edge of the screen from being clipped off; again, this is not usually necessary to set on modern HDTVs).
Even with an external display attached (mirrored or expanding the desktop), AirPlay Mirroring is still available. The pulldown AirPlay menu changes to reflect additional options, as you can now mirror the display with your external monitor independently from mirroring your display to however many Apple TV devices you have on your local network (below).
Because AirPlay Mirroring is a function of the system (dependent upon CPU video encoding hardware), it doesn't count against the number of directly-connected displays your video hardware can support.
New AirPlay features for older Macs
While Macs that are more than a year and a half old don't have the hardware to support wireless video mirroring, they can still make use of audio AirPlay features in Mountain Lion. Currently, under the Sound pane in System Preferences, the only Outputs available are hardware devices, such as internal speakers, headphones, or USB or line-out speakers (below).
Under Mountain Lion, even Macs that can't support AirPlay Mirroring can support wireless audio output (below) to designated Apple TV, AirPort Express units or other AirPlay compliant devices (including devices and receivers from Audyssey, B&W, Denon, iHome, JBL, Klipsch, Marantz, Philips, Pioneer, Samsung, Sony and Yamaha), allowing users to, for example, play games where the audio is sent out through a home stereo system.
However, unlike iTunes, the Sound Output controls don't allow you to stream audio to multiple sets of speakers at once. That means if you set system audio output to an AirPlay device, the local speakers will be muted.
Older Macs can of course still play videos to Apple TV connected screens via AirPlay within iTunes, and play audio from iTunes to multiple speakers through iTunes' "Multiple Speakers" feature (above).
AirPlay, originally named AirTunes when Apple debuted it in 2004 as a way to wirelessly stream audio from iTunes to speakers connected to the AirPort Express base station, had its name changed by Steve Jobs in 2010 after the technology was expanded to include video and photo streaming to the then-new, $99 iOS-based Apple TV.
While iTunes currently has the ability to stream both audio and video playback to Apple TV, OS X can't deliver audio or video from other apps. Additionally, because AirPlay involves encryption of streamed data, it's not easy for third party developers to send data to AirPlay devices.
New AirPlay Mirroring
All that is changing in Mountain Lion. The most obvious benefit is that hardware-compliant Macs can now do the same AirPlay Mirroring trick as last year's new iOS devices (iPhone 4S and iPad 2 or newer): anything on the screen can be mirrored to an Apple TV-connected display.
As with iOS devices, Macs need special hardware to support AirPlay Mirroring. It doesn't work on the Mid 2010 MacBook Pro, for example, but does work on early 2011 MacBook Pros, as well as mid 2011 or newer MacBook Air, iMac or Mac mini systems.
These systems are the oldest machines capable of supporting AirPlay Mirroring because they are the first to deliver dedicated hardware encoding for H.264. Without a CPU capable of crunching this task using specialized hardware, earlier Macs simply can't transmit video fast enough without a lot of heat and screaming fans.
Older Macs can already send video from iTunes to Apple TV via AirPlay, but they stop local playback while doing this. Mirroring requires the system to produce two video images, one driving the local display and one to be wirelessly delivered to the external screen.
AirPlay doesn't just relay video from the computer (or iOS device) to Apple TV. It scales down the video to fit on an HDTV resolution, and has to convert the colorspace from the computer's RGB to the native YUV that televisions use. Both tasks require a lot of processing resources, so without the extra hardware available on newer Macs, mirroring isn't possible.
The new Displays pane
Using AirPlay Mirroring on supported Macs with Mountain Lion is very easy: simply pull down the AirPlay menu and select the local Apple TV you want to mirror your display on. The options are populated via Bonjour, just as they currently are within iTunes. This quite a lot more obvious and discoverable than on the iPad, where you have to double click on the Home button and swipe to the right to find AirPlay controls (below).
The default Menu Bar options for Displays now focuses on AirPlay options, rather than the old fashioned "detect displays" and manually setting a resolution. Below, the simpler menu of Mountain Lion (right) compared to today's Lion (left). On Macs that don't support AirPlay Mirroring, this menu simply offers only to open the Displays pane in System Preferences.
Apple has also updated the Displays pane in System Preferences in Mountain Lion, even for Macs too old to support AirPlay Mirroring. Rather the offering a selection of resolutions (as today's Lion does, below top), Displays now simply defaults to the resolution "Best for built-in display," although you can manually select a non-standard resolution by clicking Scaled.
Using AirPlay Mirroring on supported Macs
You can readily identify a Mac that supports AirPlay Mirroring because it gets the AirPlay icon in the Menu Bar (and its drop down options are different too).
Once AirPlay Mirroring is initiated with a specific Apple TV unit from the Menu Bar, the Displays configuration automatically changes to the resolution "Best for AirPlay," with an option to turn on Overscan correction (usually only necessary if you're using an older CRT television; most modern flat panel displays won't cut of portions of the display because of overscan). Note that brightness controls only have an effect on the built in display.
You can manually select a different resolution from Displays, or select the resolution you want to mirror from the AirPlay Menu Bar pulldown, picking either This Mac or the name of the Apple TV you're mirroring the display to from the "Match Desktop Size To:" options.
Managing multiple displays with AirPlay Mirroring
But wait, that's not all. You can still initiate AirPlay Mirroring while connected to a secondary display. Under Mountain Lion, connecting to an external monitor works virtually the same, apart from the fact that the system, by default, pics the resolution for you. Plugged directly to my HDTV via an HDMI cable, the Displays pane for each of the two displays picks a "best for display" resolution, although either can be scaled.
The built in display supplies an option to adjust brightness (above) while the HDTV pane (below) presents options to rotate the display in 90 degree increments, set a refresh rate, and configure underscan (which creates a black margin around the image on your television to prevent elements close to the edge of the screen from being clipped off; again, this is not usually necessary to set on modern HDTVs).
Even with an external display attached (mirrored or expanding the desktop), AirPlay Mirroring is still available. The pulldown AirPlay menu changes to reflect additional options, as you can now mirror the display with your external monitor independently from mirroring your display to however many Apple TV devices you have on your local network (below).
Because AirPlay Mirroring is a function of the system (dependent upon CPU video encoding hardware), it doesn't count against the number of directly-connected displays your video hardware can support.
New AirPlay features for older Macs
While Macs that are more than a year and a half old don't have the hardware to support wireless video mirroring, they can still make use of audio AirPlay features in Mountain Lion. Currently, under the Sound pane in System Preferences, the only Outputs available are hardware devices, such as internal speakers, headphones, or USB or line-out speakers (below).
Under Mountain Lion, even Macs that can't support AirPlay Mirroring can support wireless audio output (below) to designated Apple TV, AirPort Express units or other AirPlay compliant devices (including devices and receivers from Audyssey, B&W, Denon, iHome, JBL, Klipsch, Marantz, Philips, Pioneer, Samsung, Sony and Yamaha), allowing users to, for example, play games where the audio is sent out through a home stereo system.
However, unlike iTunes, the Sound Output controls don't allow you to stream audio to multiple sets of speakers at once. That means if you set system audio output to an AirPlay device, the local speakers will be muted.
Older Macs can of course still play videos to Apple TV connected screens via AirPlay within iTunes, and play audio from iTunes to multiple speakers through iTunes' "Multiple Speakers" feature (above).
Comments
Love this. "earlier Macs simply can't transmit video fast enough [edit ... do much of anything] without a lot of heat and screaming fans' ... you've met my MBP then?/laugh
This is why I think I will be updating my mid 2010 MBP i7 after all ... darn it!
Has anyone tried using VLC to play a 1080p non QuickTime movie over airplay to an Apple TV?
That's right, if your Mac isn't new, you don't get airplay. :-(
I am running a dev preview of ML, so I think it should work when the MIRRORING OPTION COMES UP IN THE MENU BAR. Put some research into is AI!
Without screaming fans? Well, that sure is nice. Forcing my fans to run at 6000 RPM because the operating system thinks going over 100 C is a good idea and doesn't think of turning on the fans. (Over 2500 RPM)
I think a requirement is a discrete GPU, because the Macbook Air CPUs are weaker than the 2010 15 inches, so it isn't adding up if it is CPU dependant. Then again, Macbook Airs don't have GPUs either. The limits to this seems to be thunderbolt enabled, which has nothing to do with the wireless transfer rates.
I purchased my quad-core (i5 ?) imac in early 2010 for it's amazing design, huge 27" screen and speed. A MacPro was out of the question at 3X the price. I have been terrible happy using Reduxencoder/VideoMonkey and a hardware dongle from Elgato H.264 to encode video. I was always under the impression my ATI discrete chipset was able to both encode and decode H.263/H.264 video by itself (http://www.amd.com/us/products/desktop/graphics/ati-radeon-hd-4000/hd-4850/Pages/ati-radeon-hd-4850-specifications.aspx).
From that page:
ATI Avivo™ HD Video and Display Platform6
Unified Video Decoder 2 (UVD 2) for H.264/AVC, VC-1, and MPEG-2 video formats
High definition (HD) playback of Blu-ray and HD DVD video
Dual stream (HD+SD) playback support
DirectX Video Acceleration 1.0 & 2.0 support
Support for BD-Live certified applications
Hardware DivX and MPEG-1 video decode acceleration
Accelerated video transcoding & encoding for H.264 and MPEG-2 formats
ATI Avivo Video Post Processor6
Color space conversion
Chroma subsampling format conversion
Horizontal and vertical scaling
Gamma correction
Advanced vector adaptive per-pixel de-interlacing
De-blocking and noise reduction filtering
Detail enhancement
Color vibrance and flesh tone correction
Inverse telecine (2:2 and 3:2 pull-down correction)
Bad edit correction
Enhanced DVD upscaling (SD to HD)
Automatic dynamic contrast adjustment
But I have noticed with Lion the fans pick up spayed and make a racket about 30 minutes into a conversion or playback of HD content. I have had to utilize a far control utility to increase the fans speeds on the MB to keep things cool and safe. Is it possible that Apple/ATI/AMD/Nvidia have never written drivers for the video chipset encoding feature and the CPU is doing the heavy lifting still? I am starting to believe the mac platform may not be the best anymore to video creation.
Yea, my Macbook Pro has hit 100 C without the fans going to max, so i've got programs to run them at 6000 RPM all the time to keep it cool, but when I encode videos (Using a video conversion or iMovie) it doesn't use the graphics, all the load is placed on the CPU when it really shouldn't, for example running your screen on the integrated graphics if you aren't doing much on it and dedicating the discrete card to encoding and whatnot.
All the GPU does is playback and for the displays.
Why do people call this "mirroring" when it doesn't reverse right and left like a mirror? Makes no sense to me.
Apple is usually better with its terminology ("logic board" instead of "mommy board," and "restart" instead of "put on new boots.") In fact, I had to switch to the Mac because Windows made me put new boots on the computer so often that I got in trouble for impersonating a shoe salesman.
Maybe geeks never look in mirrors and don't know from personal experience how they work. Come to think of it, from the way some geeks look, that might be true.
It's good to read your article Daniel! Hope to read some new stuff soon on the Roughly Drafted site! (Sorry for being off topic).
Quote:
Originally Posted by b9bot
That's right, if your Mac isn't new, you don't get airplay. :-(
What? It won't work on an Apple ][? Scandalous!
Quote:
It doesn't work on the Mid 2010 MacBook Pro,
Is this accurate? It's not mentioned on Apple's website and other sources suggest that the feature does work on older Macs. Early betas certainly didn't support it on older Macs but I believe it was included in later builds. Has this changed again for the GM?
Well, mirroring as in it takes the same image and displays it somewhere else. Not really meant to be taken 100% literally.
I really don't think so. It shows up on my Mid 2010 Macbook Pro when I'm on a network with an apple TV on it (I don't have a 2nd or 3rd gen), so I assume it will work as it said in the bottom of the article you know if your computer is compatible if it shows up in your menu bar or something like that.
I haven't got the GM, but I doubt they will remove a feature that works already. The difference between the Mid 2010 and the early 2011 is quad core vs quad threads and thunderbolt. The airs have less power than the mid 2010 pros, and they are compatible. It doesn't make much sense to me either.
1) I don't think Apple had anything to do with this nomenclature.
2) Naming conventions don't have to be an exact and honest representation to something in the real world.
3) Consider that dual- or multiple-displays refers to additional displays where the desktop is extended, not copied. Mirroring is just a term that shows the same data.
4) Two mirrors will create an image that is not reversed from the original.
5) If you want a more apt name we could start calling it Display Samsunging but I have a feeling a certain S. Korean company wouldn't like that.
You're kidding, right?
Apple has been calling it mirroring for some time now, the only difference is it is now wireless.
1) if the older MacBooks won't support mirroring, how about just streaming? Most people who plug their Macs intotheir TVs do so, to interact with them directly on the TV screen, not to give seminars. If the problem is supporting the attached screen as well as a remote screen, then why not give us an option to disable the internal? Seems like a no-brainer, or did I miss something! This is what the iPad already does when one streams 1080p video from a window whether in mirroring or not,
2) what happens to video displayed on a web-page? Particularly Flash Video? If one goes into full screen mode, I assume the Flash video then simply fills the TV screen as well. So as long as the application, browser, etc. supports full screen there will be no issues. But what if the application doesn't support it? Will OS X Provide the option?
And what about applications like iMovie ... Will you be able to stream just the 1080p picture output rather than the entire application interface?
Quote:
Originally Posted by not candunc
Well, mirroring as in it takes the same image and displays it somewhere else. Not really meant to be taken 100% literally.
Actually, mirrors don't work that way either. Mirrors create one image from real-world objects, display it with right and left reversed, and do not project it anywhere else.
The terminology really hits the nail on the thumb, and I guess I have to get used to it.
I am kidding, but there's got to be a better word for it.
Pulled video streaming is at least possible to an Apple TV from a Mac/PC via the Apple TV through iTunes. I'm not sure if iTunes can push streaming videos to the Apple TV the way that you can with iOS devices and AirPlay but you can certainly stream audio via iTunes.
Good question! A smart system would do what AirPlay does when it detects a streaming video but I'm guessing it's not that sophisticated. I'm guessing that mirroring will work like any standard VNC where video will just be choppy and unwatchable. I hope I'm wrong or that Apple can step up their game here because this is the type of synergy that is right up their street.
Funny that Ipad2+ supports Airplay mirroring and it does not have Quick sync.
In the real world: All graphics cards since 2007 have H264 decoding/encoding in them. Apple could write solution for these graphics cards if they wanted. But no. Lazy/Greedy.
A less then 2 year old 3000K mac can't support this feature. This is why many people hate Apple.
This makes me angry!
Quote:
Originally Posted by Panu
What? It won't work on an Apple ][? Scandalous!
A 2010 MBP is hardly an Apple ][ - let's all exaggerate to make non-points.
Pretty much every nVidia GPU made since 2003 has had hardware encode/decode capability - including the GT330m, 9600m and 8600m in MBP's going back to 2007. Why Apple has chosen a specific function of the HD4000, and ONLY that function to do this encode/decode is a bit of a mystery to me.
If you don't like Samsunging then how about going along with the Retina-esque terminology and call it Display Biclopsing.