Keyframes and I-frames

[yawnmoth]

Based on what I know about I-frames (Interframes) and keyframes, they seem to be the same thing, but... this (http://www.rit.edu/~jlh1825/nbmm/proj2/index.cgi?video=9) site, as well as others, don't seem to suggest the same thing...

Also, are keyframes encoded with any specific format, like JPEG, or something? And do keyframes contribute to the final bitrate of the video, or do only the p / b-frames do that?

[Belgabor]

Originally posted by yawnmoth
Based on what I know about I-frames (Interframes) and keyframes, they seem to be the same thing, but... this (http://www.rit.edu/~jlh1825/nbmm/proj2/index.cgi?video=9) site, as well as others, don't seem to suggest the same thing...

Thats because I-frame stands for Intraframe (= Keyframe). Interframes in this notation are P-frames.

Originally posted by yawnmoth
Also, are keyframes encoded with any specific format, like JPEG, or something? And do keyframes contribute to the final bitrate of the video, or do only the p / b-frames do that?
That depends entirly on the codec.
Bitrate is video content/playtime which means everything in the video stream contributes.

Cheers
Belgabor