What is the difference between CBR and VBR?
For example, a 10-minute video could be compressed at a CBR (Constant Bit Rate) of 9 Mb/sec. This would give you extremely high quality video and take up about 675 MB. This will easily fit on a DVD-5 or DVD-R. In contrast, a 120-minute video compressed at a CBR of 9 Mb/sec would take about 8.1 GB. That much video will not fit on a DVD-5 or DVD-R. We would need to lower the data rate to about 5.5 Mb/sec to fit 120 minutes of video on to a DVD-5, and even lower yet for a DVD-R. When we lower the data rate, we lower the quality of the video.

So, how do 2 + hour movies fit on to a DVD-5 and look great? Easily with VBR encoding.

VBR stands for Variable Bit Rate. Before we encode your video, our computers will create a "database" of your video content based on the amount of change in the frame or scene. From that "database", the computer will encode your video with a variable data rate allowing a higher bit rate for scenes with pans, zooms, and fast motion, and giving scenes with little or no motion low data rates (ex. Talking head, static shot).


A graphical representation of a scene encoded both CBR and VBR

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