Instruction Manual

51
A.1.2.1 Impact of Coding Bitrate on Video Quality
For a typical MPEG-2 encoded video stream with standard resolution 720x486, GOP sequence
IBBPBBPBBPBBPBB, at 30 frames per second, the mean square error (MSE) due to bitrate can
be approximated by:
MSE
br
= 0.00001 + 1.5 / (B + B
2
/ 30000).
Where B is the bitrate in kilobits per second. The corresponding peak signal-to-noise ratio
(PSNR) value for the frame can be computed by
PSNR
br
= -10 log10MSEbr.
Figure 2-4 shows the estimated PSNR value on coding bitrate for MPEG-2 encoded video.
Figure 2-4
Estimated
PSNR on
Coding Bitrate
for Standard
Definition
MPEG-2 Video
at 30 Frames
per Second