Log in

View Full Version : B-Frames current status?


Petzku
18th January 2003, 13:43
Is it possible to use b-frames on a 2-pass encode nowadays?

unlike it says in that sticky b-frame thread i mean.

iago
18th January 2003, 13:59
Well, of course it is! ;)

frankio
18th January 2003, 18:09
I've recently encoded the first chapter of Akira PAL (which I own)
and I think there's something wrong with I/P/B decision when B-Frames are ON.
Specifically I got 123(!) consecutive I-Frames out of 238 total.

My settings:
XviD-15012003-1 Koepi's builds
Motion Search 6
Quant h263
Max I-Frame 300
Min I-Frame 1
Use Chroma Motion
NO Qpel
DX50 B-VOP compat

B ON - I/P/B: 238/1331/2535 - 1st pass size: 38MB
B OFF - I/P/B: 66/4038/0 - 1st pass size: 45MB

Also setting Min I-Frame Interval greater than 1 didn't change much.
In the attached image the "burst" of I-Frame appears where the bitrate curve (reported by StatsReader) has a high slope (?).

I can give more details if needed.

to XviD Team: keep up the good work!