ffmpeg_git -f jack -i ffmpeg -f x11grab -r 21 -s 1440x900 -i :0.0 -c:a libmp3lame -b:a 96k -ar 44100 -c:v libx264 -pix_fmt yuv420p -crf 24 -b:v 925k -minrate 800k -maxrate 925k -bufsize 325k -preset veryfast -threads 6 -f flv '<server>'
ffmpeg version N-60052-g91f4394 Copyright (c) 2000-2014 the FFmpeg developers
  built on Jan 23 2014 06:43:35 with gcc 4.7.3 (Gentoo 4.7.3-r1 p1.3, pie-0.5.5)
  configuration: --libdir=/usr/lib64 --extra-cflags=-O2 --enable-gpl --enable-x11grab --enable-libx264 --enable-libmp3lame --enable-avresample --enable-filter=asyncts
  libavutil      52. 63.100 / 52. 63.100
  libavcodec     55. 48.102 / 55. 48.102
  libavformat    55. 25.100 / 55. 25.100
  libavdevice    55.  5.102 / 55.  5.102
  libavfilter     4.  1.100 /  4.  1.100
  libavresample   1.  1.  0 /  1.  1.  0
  libswscale      2.  5.101 /  2.  5.101
  libswresample   0. 17.104 /  0. 17.104
  libpostproc    52.  3.100 / 52.  3.100
[jack @ 0x2419640] JACK client registered and activated (rate=48000Hz, buffer_size=1024 frames)
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, jack, from 'ffmpeg':
  Duration: N/A, start: 1390488557.055175, bitrate: 3072 kb/s
    Stream #0:0: Audio: pcm_f32le, 48000 Hz, stereo, flt, 3072 kb/s
[x11grab @ 0x2441dc0] device: :0.0 -> display: :0.0 x: 0 y: 0 width: 1440 height: 900
[x11grab @ 0x2441dc0] shared memory extension found
Input #1, x11grab, from ':0.0':
  Duration: N/A, start: 1390488557.104036, bitrate: 870912 kb/s
    Stream #1:0: Video: rawvideo (BGR[0] / 0x524742), bgr0, 1440x900, 870912 kb/s, 21 tbr, 1000k tbn, 21 tbc
[libx264 @ 0x24567a0] using cpu capabilities: MMX2 SSE2Fast LZCNT
[libx264 @ 0x24567a0] profile High, level 4.0
[libx264 @ 0x24567a0] 264 - core 138 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013 - http://www.videolan.org/x264.html - options: cabac=1 ref=1 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=2 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=6 lookahead_threads=2 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=1 keyint=250 keyint_min=21 scenecut=40 intra_refresh=0 rc_lookahead=10 rc=crf mbtree=1 crf=24.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=925 vbv_bufsize=325 crf_max=0.0 nal_hrd=none ip_ratio=1.40 aq=1:1.00
Output #0, flv, to '<server>':
  Metadata:
    encoder         : Lavf55.25.100
    Stream #0:0: Video: h264 (libx264) ([7][0][0][0] / 0x0007), yuv420p, 1440x900, q=-1--1, 925 kb/s, 1k tbn, 21 tbc
    Stream #0:1: Audio: mp3 (libmp3lame) ([2][0][0][0] / 0x0002), 44100 Hz, stereo, fltp, 96 kb/s
Stream mapping:
  Stream #1:0 -> #0:0 (rawvideo -> libx264)
  Stream #0:0 -> #0:1 (pcm_f32le -> libmp3lame)
Press [q] to stop, [?] for help
[jack @ 0x2419640] Audio packet xrun
    Last message repeated 1 times
[flv @ 0x2456200] Failed to update header with correct duration.ate= 147.7kbits/s
[flv @ 0x2456200] Failed to update header with correct filesize.
frame=  267 fps= 22 q=-1.0 Lsize=     309kB time=00:00:13.52 bitrate= 187.4kbits/s
video:152kB audio:145kB subtitle:0 global headers:0kB muxing overhead 4.371712%
[libx264 @ 0x24567a0] frame I:2     Avg QP:27.98  size: 31867
[libx264 @ 0x24567a0] frame P:67    Avg QP:14.35  size:  1208
[libx264 @ 0x24567a0] frame B:198   Avg QP:14.55  size:    50
[libx264 @ 0x24567a0] consecutive B-frames:  1.1%  0.0%  0.0% 98.9%
[libx264 @ 0x24567a0] mb I  I16..4: 78.6%  4.5% 16.9%
[libx264 @ 0x24567a0] mb P  I16..4:  0.4%  0.0%  0.0%  P16..4:  2.0%  0.1%  0.0%  0.0%  0.0%    skip:97.5%
[libx264 @ 0x24567a0] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  0.0%  0.0%  0.0%  direct: 0.0%  skip:100.0%  L0:36.3% L1:63.7% BI: 0.0%
[libx264 @ 0x24567a0] 8x8 transform intra:4.3% inter:3.4%
[libx264 @ 0x24567a0] coded y,uvDC,uvAC intra: 17.9% 2.7% 1.6% inter: 0.3% 0.1% 0.0%
[libx264 @ 0x24567a0] i16 v,h,dc,p: 72% 26%  1%  0%
[libx264 @ 0x24567a0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 19% 52% 21%  2%  1%  0%  1%  0%  4%
[libx264 @ 0x24567a0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 30% 28% 21%  2%  8%  2%  2%  3%  4%
[libx264 @ 0x24567a0] i8c dc,h,v,p: 85% 13%  2%  0%
[libx264 @ 0x24567a0] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x24567a0] kb/s:97.26