understanding libx264 output

Question

I used libx264 in ffmpeg to encode . Finally i got below output .

Can anyone guide me understanding & interpreting this?? Any reference/documentation?

01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] frame I:7     Avg QP:27.51  size: 11996
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] frame P:32    Avg QP:26.90  size:   217
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] frame B:25    Avg QP:32.73  size:    39
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] consecutive B-frames: 20.0% 80.0%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] mb I  I16..4: 74.1% 17.0%  8.9%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] mb P  I16..4:  0.7%  0.1%  0.0%  P16..4:  2.0%  0.3%  0.2%  0.0%  0.0%    skip:96.6%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  1.2%  0.0%  0.0%  direct: 0.1%  skip:98.8%  L0: 5.5% L1:94.5% BI: 0.0%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] final ratefactor: 22.43
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] 8x8 transform intra:16.9% inter:51.1%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] coded y,uvDC,uvAC intra: 12.8% 27.2% 24.4% inter: 0.3% 0.6% 0.0%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] i16 v,h,dc,p: 95%  5%  0%  0%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu:  2% 30% 60%  0%  1%  0%  2%  0%  4%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu:  7% 58% 10%  2%  4%  2%  9%  1%  8%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] i8c dc,h,v,p: 14% 81%  3%  3%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] Weighted P-Frames: Y:0.0% UV:0.0%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] ref P L0: 81.2% 16.6%  1.8%  0.4%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] ref B L0: 70.8% 29.2%
01-01 06:34:43.650: I/stderr(6603): [libx264 @ 0xdd2040] kb/s:287.21

Edit: I want to know what determines rate factor? Is it relevant to fps? What is QP and it's relation with rate factor?

Thank You!!

Answer 1

All this output statistics are described here: https://en.wikibooks.org/wiki/MeGUI/x264_Settings/x264_Stats_Output