View Full Version : Bit Rate Numbers


Sean Malone
November 18th, 2009, 09:33 PM
This has probably been covered some ware but I can't find it. I remember reading a few years back that its best to set bit rates to a number that’s divisible by 32 (it was probably 8 or 16 in the early days). I don't know if its still applicable, but a guy in our building and I were discussing bit rates today and it came up. Is this another famous myth or is there any validity to it?

Perrone Ford
November 18th, 2009, 09:44 PM
Bit rates??? No. Frame sizes.. yes. But not by 32. Generally by 8 or by 4. Why on earth would bit rate need to be divisible by anything? With VBR it's essentially impossible anyway.

Sean Malone
November 18th, 2009, 10:15 PM
Sounds like myth. VBR is a great point. Glade I asked though, I didn't know about the "Frame Size" aspect of things.

Thanks,

Shaun Roemich
November 19th, 2009, 12:11 AM
MPEG-1 dimensions need to be divisible by 8, but not bitrate.

Robert M Wright
December 11th, 2009, 09:42 PM
Even if the codec doesn't require it, making frame dimensions divisible by 8 will help make encoding more efficient (even if just slightly).