[Question]: to use B frame need to enable Peanalyse ?

[Ryu0833]

Hello
I have rx 7600xt and i know that the vcn 4.0 support b frame dose in natively support it or i need to enable Preanalyse
And i am using the latest update of obs
Even i see the code when enable Preanalyse in obs only enable adaptive_gop
So my question are

1. can i use b-frame without Preanalyse or i need Preanalyse to work ?
   2)If i enable Preanalyse for the momment is there penalty in lantecy and performance (there are no lookahead or any option from Preanalyse)
   Thank for your time and sorry for my english.

[MikhailAMD]

Yes, you can use B-frames without PA. You need to set AMF_VIDEO_ENCODER_B_PIC_PATTERN to N and for older drivers set AMF_VIDEO_ENCODER_MAX_NUM_REFRAMES = N. You should expect to feed N+1 frames to the encoder before you get the first compressed frame. B-frames add latency even without PA.
Yes, PA adds latency and overhead and for real-time applications should be used with care. In OBS parameters were fine-tuned to get better quality with PA but keep real-time.