# avconv -f x11grab -i :1.0 -s qxga /tmp/out.mp4
avconv version 0.8.3-6:0.8.3-1~bpo60+1, Copyright (c) 2000-2012 the Libav developers
  built on Jun 17 2012 12:00:40 with gcc 4.4.5
[x11grab @ 0x9087000] device: :1.0 -> display: :1.0 x: 0 y: 0 width: 640 height: 480
[x11grab @ 0x9087000] shared memory extension  found
[x11grab @ 0x9087000] Estimating duration from bitrate, this may be inaccurate
Input #0, x11grab, from ':1.0':
  Duration: N/A, start: 1352567967.862547, bitrate: 294617 kb/s
    Stream #0.0: Video: rawvideo, bgra, 640x480, 294617 kb/s, 29.97 tbr, 1000k tbn, 29.97 tbc
Incompatible pixel format 'bgra' for codec 'libx264', auto-selecting format 'yuv420p'
[buffer @ 0x90945a0] w:640 h:480 pixfmt:bgra
[scale @ 0x9093e20] w:640 h:480 fmt:bgra -> w:2048 h:1536 fmt:yuv420p flags:0x4
[libx264 @ 0x9093000] using cpu capabilities: MMX2 SSE2Fast SSSE3 Cache64 SlowCTZ SlowAtom
[libx264 @ 0x9093000] profile Main, level 5.0
[libx264 @ 0x9093000] 264 - core 120 r2151 a3f4407 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x1:0x111 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=0 b_adapt=1 b_bias=0 direct=1 weightb=0 open_gop=1 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.25 aq=1:1.00
Output #0, mp4, to '/tmp/out.mp4':
  Metadata:
    encoder         : Lavf53.21.0
    Stream #0.0: Video: libx264, yuv420p, 2048x1536, q=-1--1, 30k tbn, 29.97 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo -> libx264)
Press ctrl-c to stop encoding
frame=   17 fps=  0 q=0.0 size=       0kB time=10000000000.00 bitrate=   0.0kbits/s dup=13 drop=0
frame=   33 fps= 25 q=0.0 size=       0kB time=10000000000.00 bitrate=   0.0kbits/s dup=27 drop=0
frame=   52 fps= 12 q=31.0 size=     134kB time=0.03 bitrate=32875.0kbits/s dup=44 drop=0
frame=  136 fps=  9 q=29.0 size=     152kB time=2.84 bitrate= 438.4kbits/s dup=127 drop=0
frame=  136 fps=  7 q=-1.0 Lsize=     160kB time=4.50 bitrate= 291.7kbits/s dup=127 drop=0

video:158kB audio:0kB global headers:0kB muxing overhead 1.517333%
[libx264 @ 0x9093000] frame I:1     Avg QP:20.13  size:136201
[libx264 @ 0x9093000] frame P:36    Avg QP:27.89  size:   282
[libx264 @ 0x9093000] frame B:99    Avg QP:29.12  size:   149
[libx264 @ 0x9093000] consecutive B-frames:  2.9%  0.0%  0.0% 97.1%
[libx264 @ 0x9093000] mb I  I16..4: 77.5%  0.0% 22.5%
[libx264 @ 0x9093000] mb P  I16..4:  0.3%  0.0%  0.0%  P16..4:  0.1%  0.0%  0.0%  0.0%  0.0%    skip:99.5%
[libx264 @ 0x9093000] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  0.4%  0.0%  0.0%  direct: 0.0%  skip:99.5%  L0:17.8% L1:82.2% BI: 0.0%
[libx264 @ 0x9093000] coded y,uvDC,uvAC intra: 15.8% 17.0% 16.1% inter: 0.0% 0.0% 0.0%
[libx264 @ 0x9093000] i16 v,h,dc,p: 97%  2%  1%  0%
[libx264 @ 0x9093000] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 40% 22% 10%  5%  8%  4%  4%  4%  4%
[libx264 @ 0x9093000] i8c dc,h,v,p: 86%  6%  6%  1%
[libx264 @ 0x9093000] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x9093000] ref P L0: 62.3% 28.5%  4.9%  4.3%
[libx264 @ 0x9093000] ref B L0: 64.4% 35.6%
[libx264 @ 0x9093000] kb/s:284.00
Received signal 15: terminating.