Choosing Your Bitrate Control Technique

July 25, 2017 @ 2 PM EST

Whenever you encode a file, you must choose a bitrate control technique, or how the video

data rate is allocated within the fi le. For most producers, this means a choice between constant

bitrate (CBR) and variable bitrate (VBR) encoding. While these choices have been available since

the dawn of H.264 (and MPEG-2 and before it, for that matter) there still is no consensus as to

which is best to use.

 

In general, the CBR-versus-VBR decision involves a debate between quality and deliverability.

It’s generally accepted that VBR produces better quality than CBR, although it probably doesn’t

make as big a difference as you might think. Despite the quality advantage, many producers

use CBR over concerns that variances in the VBR bitrate will make their files harder to deliver—

particularly over constrained bitrate connections like 3G and 4G. As you’ll learn in this webinar,

these concerns are appropriate. Otherwise, you will learn:

 

  •  how VBR and CBR work
  •  differences in both overall and transient frame quality
  •  how both techniques impact file deliverability
  •  what the Video Buffering Verifier (VBV) is and how it affects bitrate control and quality
  •  best practices for encoding with CBR and VBR