Screenshot comparison source/encode

[Mechaniol]

Hi,

I need to compare the source VS the encode.
Is it better to compare source "frame P" VS encode "frame B" or source "frame B" VS encode "frame B" ?

Thank for your help !

[Asmodian]

It is important to only compare frames of the same type, so P frames to P frames and B frames to B frames.

[Mechaniol]

OK, thanks!

And...is it possible that a movie (source) has only Frames P and frames I ? I cannot find any frames B in that movie...

[Asmodian]

Yes. It is common, especially for older encoders, to not use B frames.

[Mechaniol]

OK, thank you for your help !
:)