Streaming Judder-Free 24p Videos to Smart TVs with SofaPlay

One more thing for the movie nerds …

So-called Judder is the “result of a mismatch between the refresh rate of a TV panel and the frequency of 24 hz video”. This is a problem especially if you’re using AirPlay and Apple TV to stream 24p video content to your TV as the output frame rate of Apple TV is locked at 60p. There is currently no way to display native 24p videos with Apple TV except for TVs that support reverse 3:2 pull-down. See this excellent article on rtings.com for more information.

As SofaPlay streams directly to compatible TVs, the video content is displayed through the built-in player software without going through HDMI or another connected device. So, if your TV supports native 24p playback, SofaPlay should too.

We’ve tested this on a rather old Samsung Smart TV (UE40D5700) using the test video and method described at rtings.com:

The test video cycles a white square through 24 slots in one second. While it plays, we photograph the screen, using a 1-second exposure.

On the left side, you can see the test video streamed with SofaPlay, on the right side the same video streamed with AirPlay and Apple TV:

If the color of the squares is a uniform grayish color, it means each of the 24 slots displayed the square for the same amount of time, and so the TV has passed the test. If certain squares are light, and others are dark, it means the TV failed to play each frame for an even amount of time, and therefore had judder.
left: streaming the test video with SofaPlay — right: streaming the test video with AirPlay & AppleTV

If you’re interested in streaming 24p video with SofaPlay, please try SofaPlay Lite first to check if you TV setup is compatible. You can use the same method as described above at rtings.com