AirPlay vs. Airplay Mirror

[JackLeBoul]

Running into an issue with my ATV 3 and Airplay Mirroring when I upgraded to 10.8.

My Setup:

Mid 2012 MBA (10.8.2) + ATV3 (5.1) + 2012 Airport Express (@300Mbit/s)

When I play a movie with iTunes I noticed on my network monitor that the MBA send the signals at 25 - 40 Mbit/s and the movie plays fine. (home movie shoot at 10 Mbit/s H.264)

However, when I play the same movie on the MBA and Airplay Mirror, the network monitor register only 7 - 12 Mbit /s and the movie lags & shutters. In fact even an SD version plays poorly with Airplay Mirror.

For some reason the MBA thru-put is significantly less with Airplay Mirroring than Airplay (via iTunes).

So, has anyone experienced something similar, have I missed a setting somewhere?

thanks and regards

[waw74]

that's just the way it works

airplay sends the raw file, and the aTV plays it

mirroring has to convert the whole screen on the fly and send it.

[JackLeBoul]

Originally Posted by waw74

that's just the way it works

airplay sends the raw file, and the aTV plays it

mirroring has to convert the whole screen on the fly and send it.

Hi,
I am not sure I got your answer.

My point is that the MBA does not send sufficient amount of data (9-12 Mbit/s) to play the airplay mirror movie smoothly, while via iTunes airplay it does (25-40Mbit/s). This only happened as of 10.8.2.

The computer, the network and ATV has sufficient bandwidth to transmit higher data thru-put than it actual does.

[waw74]

airplay is just sending the movie file and playing it directly on the aTV.

mirroring will
-play the file on the computer screen
-convert the whole screen image to a compatible format to play on the aTV.
-send that converted image to the aTV and play it there.

the air is converting the screen image to a lower bitrate than the original image, so you're also limited by the power of the conversion chip in the air.



think of it this way...

airplay, send a DVD to someone and they play it on their TV.

airplay mirror, play the DVD on your home television, and point a camera at the television screen, and then send the tape from that camera so they can play that.

[JackLeBoul]

Originally Posted by waw74

airplay is just sending the movie file and playing it directly on the aTV.

mirroring will
-play the file on the computer screen
-convert the whole screen image to a compatible format to play on the aTV.
-send that converted image to the aTV and play it there.

the air is converting the screen image to a lower bitrate than the original image, so you're also limited by the power of the conversion chip in the air.



think of it this way...

airplay, send a DVD to someone and they play it on their TV.

airplay mirror, play the DVD on your home television, and point a camera at the television screen, and then send the tape from that camera so they can play that.

I get the difference between the two.
However, since 10.8.2, on my MBA and my iMac, do not send enough data to play movies smoothly.