iPad 2 iOS 5 AirPlay Mirroring Demo + Latency Measured

Wednesday, June 8, 2011
By OP Editor

Is the iOS 5 AirPlay wireless display mirroring fast enough for gaming? OP measures the iPad 2 to Apple TV latency.

Infinity Blade, iPad Airplay Mirroring

Video: iOS 5 AirPlay Display Mirroring

Here’s a video from youtube user wentsungtsai showing the wireless iOS 5 AirPlay display mirroring. Devices: white iPad 2 with iOS 5 Developer Preview beta 1, and Apple TV.

ObamaPacman measured the latency between the iPad and TV display. When something happened on iPad, OP counted the number of frames it takes for the TV to display the same scene. The rough benchmark of latency is as follows:

  • iOS desktop: 7 frames
  • Safari: 6 to 7 frames
  • Sling Player: 10 frames
  • Angry Birds: 7 to 9 frames
  • Infinity Blade (at 2:30): 7 frames

Do the math with video at 30 frames per second, each frame is about 33.3 milliseconds.

Result? AirPlay video mirroring latency is currently around 200 to 333 milliseconds with iOS 5 developer beta 1. The video uploader claims “50~100ms” latency. OP is not sure where that came from.

Analysis

What does the fraction second delay mean for AirPlay streaming?

  • It’s fine for presentations and web browsing
  • It’s fine for video streaming, as long as you are not watching it on the iPad
  • Might not be good for DJ
  • Some games (such as angry birds) are not designed to be played by looking at the TV due to lack of cursor, so latency won’t matter because you’ll be looking at the iPad.
  • Games such as Max Adventure may or may not see an impact
  • Racing games, perfect for big screen, might need something with lower latency. Ideally, the latency for fast paced games should be no more than 1 to 2 video frames (33 to 66 ms) for the best experience.

Keep in mind that this is beta 1. Speed of software is typically optimized toward the end of the development cycle, so Apple is likely to improve the speed of iOS 5 display mirroring in the next few months. Meanwhile, for those who want to connect to TV today, you can buy the Apple iPad HDMI adapter for $39.00.

PS. For those who want to try this now with iOS 5, both devices need to be provisioned under an Apple developer account.

Share

Related Posts

  1. Apple AirPlay Explained [Video]
  2. iOS 5 on iPad 2, Developer Preview
  3. iOS 5.1 Beta Reveals Apple testing iPhone 5, iPad 3, New Apple TV
  4. ESPN App Adds iPhone, iPod touch, iPad Live Video Streaming [Demo]
  5. OS X 10.8 Mountain Lion Apple Walkthrough [Video]

Tags: Analysis, Apple, Benchmark, iPad, Video

2 Responses to “iPad 2 iOS 5 AirPlay Mirroring Demo + Latency Measured”

  1. Harsha

    how are you measuring the latencies in different applications.

    at the moment i am able to do some latencies using a frameclock sort of app by comparing the differences in frame number shown on the TV and IPAD by running the app in the airplay mirror mode.

    looks like its a consisent 5 frame difference meaning 130ms

    Any help to measure fps while running other frames is highly appreciated

    1
    • Hi Harsha,

      I just counted number of frames it took for same same element to show up on TV. You can measure with even better accuracy if you use a 60FPS or better camera.

      However, this video was beta iOS, so finished iOS 5 should be faster.

      1.1

Site Search

iPad Air 2 Case

Popular Tags