What does the summary output of the coding with ffmpeg means

[libx264 @ 03897b40] frame I:1596 Avg QP:17.81 size: 40763
[libx264 @ 03897b40] frame P:17543 Avg QP:20.85 size: 12069
[libx264 @ 03897b40] frame B:43312 Avg QP:23.91 size: 2662
[libx264 @ 03897b40] consecutive B-frames: 3.5% 4.4% 23.0% 69.1%
[libx264 @ 03897b40] mb I I16..4: 29.8% 0.0% 70.2%
[libx264 @ 03897b40] mb P I16..4: 6.6% 0.0% 4.8% P16..4: 46.9% 21.2% 11.1% 0.0% 0.0% skip: 9.4%
[libx264 @ 03897b40] mb B I16..4: 0.5% 0.0% 0.2% B16..8: 43.0% 4.7% 0.9% direct: 6.7% skip:44.0% L0:38.1% L1:52.3% BI: 9.6%
[libx264 @ 03897b40] direct mvs spatial:100.0% temporal:0.0%
[libx264 @ 03897b40] coded y,uvDC,uvAC intra: 60.1% 79.1% 30.3% inter: 17.3% 30.3% 1.4%
[libx264 @ 03897b40] i16 v,h,dc,p: 28% 21% 17% 35%
[libx264 @ 03897b40] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 10% 8% 7% 9% 13% 12% 14% 11% 16%
[libx264 @ 03897b40] i8c dc,h,v,p: 28% 33% 25% 14%
[libx264 @ 03897b40] Weighted P-Frames: Y:7.2% UV:5.8%
[libx264 @ 03897b40] ref P L0: 58.8% 13.3% 21.3% 6.5% 0.1%
[libx264 @ 03897b40] ref B L0: 85.9% 12.3% 1.8%
[libx264 @ 03897b40] ref B L1: 91.6% 8.4%
[libx264 @ 03897b40] kb/s:1505.22

is there a way to get an idea of the quality of the video and if the conversion succeeded or did it quit in the middle of the conversion.