In the movie theater, projectors display 24 frames per second (FPS). Film purists love to watch their movies at home the same way. TV Shows, on the other hand, are typically filmed at 30 FPS. As a result, for a long time, most TVs were only set up to handle only 30 FPS and films were converted to video to be compatible. The conversion process is known as 3:2 or 2:3 pull down. Basically, this process figures out a way to elegantly fill in the missing frames when going from 24 to 30 FPS. DVD players applied this process on-the-fly for TVs that couldn’t handle the film’s native frame rate. The problem is that the conversion to 30 FPS introduces a slight jerkiness when the camera pans across a scene. This is also known as “judder.” If you’re not looking for it, you may not even notice it.
Nowadays, most – but not all – 1080P HDTVs, with refresh rates of 120Hz or 240Hz, can show video sources at 24 FPS. Most Blu-ray and DVD players are capable of outputting movies at their native frame rate as well. To see if your TV and Blu-ray player can do this, you may have to get out your product manuals (or put your googling skills to the test).
In the world of streaming video, Netflix usually encodes movies at their native frame rates. Unfortunately, the Netflix players that offer 1080P – the Roku 2 and the Playstation3, cannot output at 24 FPS. Instead, it’s 60Hz, which doubles the 30 FPS (each frame is displayed twice). While the PS3 can output 24 FPS for Blu-ray disks, it can’t do it for Netflix. We can hope that the Roku 2 and the PS3 will get a software update to support 24 FPS in the future.
The Boxee does have a setting called “Match screen refresh rate to video”. When I saw this, I was excited, thinking the Boxee would be smart enough to see what Netflix had encoded the video at and properly display it on my HDTV. It didn’t seem like the setting worked properly with Netflix and then it occurred to me why it wouldn’t work. The Boxee (and most other Netflix players) have access to the 720P, not the 1080P, HD video streams. The problem was with my Samsung LCD. While it supported 720P, it did not support 24 FPS at that resolution. So, the Boxee converts the 720P Netflix stream to 1080P/30 (actually 60 Hz).
As a result, here in the Hub, we’re still waiting for the ultimate Netflix player for audio and video. Hopefully, one day there will be a player that can natively display a show’s encoded frame rate and stream 1080P from Netflix. Soon as we find it, we’ll let you know.
|HDTV displaying 24 FPS|
|Boxee’s video options set up to force 24 FPS (click to enlarge).|