Bi-Directional Encoding

[ThePanther]

Can anyone tell me when to use Bi-Directional encoding.

From reading some post, its suggested to only use Bi-Directional
encoding with low bitrates and to leave it off for high bitrates.

Can anyone tell me what is considered a low bitrate and what is consider a high bitrate, or is the some type of calculation you
need to make to decide.

Thanks

[N_F]

Basically: Always use it unless you're getting undersized files, in which case you might want to turn it off.

Also, it's wrong to talk about bitrates in these cases, it's a matter of how well a specific movie compresses. An example:

Clerks is a B&W movie that's real noisy. The Panic Room is a very dark movie that compresses extremely well.

Quality-wise, The Panic Room at 500 kbps may be equal to Clerks at 2000 kbps (of course this is also very subjective, but you get the picture).

If you already have a high resolution and still get comp. values over 75% you might wanna turn B-frames off, otherwise leave it on.

[ThePanther]

Thanks Mate