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• Tracking User Acquisition and Social Media Activity with Piwik

  25 avril 2017, par Florian Hieß — Community

  Being able to monitor user acquisition and social media activity is essential for determining whether the outcome of your campaigns is in line with the business objectives. Determining the source of each website visit that gets you closer to your business goals enables you to focus your efforts in the directions that are worth it. In this article you will learn why it is important to identify your traffic sources and how you can track user acquisition with Piwik Analytics.

  Why Is It Important to Identify Traffic Sources on Your Website ?

  Since brands nowadays use multiple channels for promotion and advertising, identifying the touch points and traffic sources of a lead or customer seems to become more and more difficult. And yet, this channel multiplication is what makes the source of a purchase more important. Once you identify the traffic origin and how each source is performing you are able to increase your efforts on the best performers, both in terms of human resources and monetary investments, to attract more leads or customers in these marketing channels.

  The default referrer types are defined by :

  • Search engine
  • Direct traffic
  • Websites and
  • Campaigns

  But consider that within the “Campaigns” type, each of the following referrers is a possible traffic source for your website and can be tracked with the Piwik URL builder :

  • Google AdWords
  • Display Ads, Banners
  • Links in Newsletters, Emailing
  • Affiliate links
  • Tweets
  • Facebook Ads

  Measure your performance and conversion

  With so many options, wouldn’t you like to know which one of them worked best ? To rate channels based on their performance, you first need to establish conversion goals and attribution.

  A conversion can be anything from sign-ups or downloads to leads, registered users and even paying customers. Define conversions based on what you want people to do once they’ve landed on your website.

  

  You need to define each conversion type in the Piwik dashboard, so that the analytics platform knows what to track. As far as attribution goes, Piwik by default links the conversion and attributes to the last seen (non-direct) referrer. You are able to change that to the first referrer in the attribution line by following the instructions in this conversion attribution FAQ.

  Track Your User Acquisition Right with Piwik

  Using the Piwik URL Builder tool, you can tag each URL you promote in your campaigns using relevant keywords. Provided that your URLs are tagged, whenever someone clicks on them, the campaign will be listed as the referrer in the Piwik dashboard. Once you’ve generated trackable URLs, you can include them in your social media posts which could be planned and scheduled using a social media management tool such as Swat.io.

  

  Campaign URLs work wonders for telling which campaign helped you reach your goals faster, more efficiently and so on but they do have a downside. They only work for URLs that you’ve shared. If someone decides to share a link of yours on social media they won’t be tagged beforehands. This is where the Referrers section of Piwik comes in handy, as it acts as a backup for tracking traffic sources. The overview tab features a graph that can help you identify when spikes occurred.

  

  As well as a numerical representation of the main referrer categories for the selected time period.

  

  Switching from Overview to Websites & Social, you can see a graphical representation of the social networks acting as referrers. The visualization can be changed to bar graphs or table, and can be easily exported in various formats for reports.

  

  The websites list features not only the social referrers, but all of the websites generating visits to your website. With Piwik you should not have issues with referrer spam, as the Piwik core team has tackled this problem early on, as detailed in how to stop referrer spam. Our analytics spam blacklist is a public project on GitHub.

  

  Assuming that you’re relying only on Facebook and VK.com for your campaigns, as the above screenshot would suggest, you might want to give paid advertising a try on these two social networks. Paid ads can increase reach and engagement, can get more relevant visitors to your website and can have a snowball effect in a short period of time.

  What Social Networks Can Piwik Track ?

  Piwik’s built-in social network list is quite extensive, as it currently features 70 platforms. The entries range from popular social networks such as Facebook, Twitter and LinkedIn to more obscure ones such as Renren. However, this list is not available by default, and to see it or alter it, you would need a third-party plugin.

  How Does the Referrers Manager Plugin for Piwik Work ?

  The Referrers Manager plugin for Piwik provides access to the list of search engines and social networks that this analytics platform can handle by default. The simple plugin can come in handy when sorting out referrers. First of all, it displays a list of all search engines and social networks that Piwik can handle by default. Secondly, it enables users to disable/enable the platform’s default social network list. And using Referrers Manager, you can add custom engines or social networks to the referrers list in case they’re not already available.

  

  Conclusions

  Piwik is a very capable analytics platform as it is, but combined with third-party plugins such as Referrers Manager, it can provide even better insights on where your visitors are coming from. Remember to correlate the referrers with goals in order to determine which website or social network performs best in your context. And don’t forget to assign a monetary revenue value to each goal, in order to determine your social media ROI with greater accuracy.

• Improve ffmpeg x11grab screen capture performance

  10 janvier 2020, par Toby Eggitt

  I have been doing screen-only (no sound) capture using ffmpeg with libx264 for the encoding quite successfully on an old machine built around a Core2 Quad Q6600 processor. I now need to include audio in this, but the fans on this ancient machine are too loud. So, I found a fanless motherboard (https://www.asrock.com/mb/Intel/J5005-ITX/index.asp) that has an Intel Pentium Silver J5005 processor and decided to use this instead. The CPU’s benchmarks put it in a similar bracket to the Q6600, and the general performance seems to be significantly better, presumably at least in part because it’s now using DDR4 memory that’s faster access.

  However, the machine fails horribly at the screen capture. It’s missing frames all over the place ; I actually end up with video that’s missing almost half the frames, and plays back at about double speed. Also, any audio is just messed up so badly I can hardly think how to describe it, best I can come up with is that I get perhaps a quarter second of sound then a few seconds pause (the video meanwhile is actually still playing back, albeit with no sense of time).

  Some things occur to me that might be the cause, or cure, of my troubles, some of which I might be able to fix, others not so much. What other things should I try ? (I’d prefer to avoid simply throwing money at the issue with random ideas that are baseless !)

  1) perhaps the CPU lacks some "extensions" to the instruction set (I recall years ago some CPUs gaining MMX extensions") so that the CPU is fast at mundane computing but sucks at video encoding.

  2) perhaps the fact that the old machine had a dedicated graphics card, while this new one is sharing main memory with the graphics system means that reading the screen pixels is much slower.

  3) perhaps the fact that this new machine has a single DDR4 memory stick in it means that I’m forcing all the memory reads and writes for the computations through the same memory as is holding the screen, and that’s too much (implying that adding an additional memory stick might jus possibly help ?)

  4) perhaps there’s some bios setting that would allow more efficient sharing of video memory ?

  5) my favorite, perhaps there’s a better compression library that I could use to get decent quality screen capture with much less CPU usage.

  I should also note that I have tried this with -threads 0, and the CPU usage hovers between 100% and 200% ; around 100% when the screen is static, and rising as I move windows around and otherwise create more output.

  6) the motherboard claims to have some kind of hardware video encoder built into it. I haven’t paid this any attention to this point, as I assumed it was for the purpose of taking HDMI input and encoding it, but maybe there’s a way to use this, if so, what libraries might I need to get ffmpeg to do this.

  Edits :

  • This is an off the shelf ffmpeg. I’m certainly willing to try building it myself if I have some idea what I should do different.
  • The motherboard claims to have hardware encoders, but I’m struggling to find out what they are (seems like it’s an Intel chip called "UHD Graphics 605" but nothing I can find suggests ffmpeg can work with that)

  • command line right now has been (without audio) :

    ffmpeg  -video_size 1280x720   -f x11grab  -i ${DISPLAY}+100,100  -vcodec libx264  -f alsa -i pulse -acodec ac3 -threads 0  ./video$(date +%F-%H-%M-%S).mp4

  Log from a short recording session is :

  ffmpeg version 3.4.6-0ubuntu0.18.04.1 Copyright (c) 2000-2019 the FFmpeg developers
  
    built with gcc 7 (Ubuntu 7.3.0-16ubuntu3)
  
    configuration: --prefix=/usr --extra-version=0ubuntu0.18.04.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  
    libavutil      55. 78.100 / 55. 78.100
  
    libavcodec     57.107.100 / 57.107.100
  
    libavformat    57. 83.100 / 57. 83.100
  
    libavdevice    57. 10.100 / 57. 10.100
  
    libavfilter     6.107.100 /  6.107.100
  
    libavresample   3.  7.  0 /  3.  7.  0
  
    libswscale      4.  8.100 /  4.  8.100
  
    libswresample   2.  9.100 /  2.  9.100
  
    libpostproc    54.  7.100 / 54.  7.100
  
  [x11grab @ 0x561a723e5ac0] Stream #0: not enough frames to estimate rate; consider increasing probesize
  
  Input #0, x11grab, from ':0+100,100':
  
    Duration: N/A, start: 1578693116.465807, bitrate: N/A
  
      Stream #0:0: Video: rawvideo (BGR[0] / 0x524742), bgr0, 1280x720, 29.97 fps, 1000k tbr, 1000k tbn, 1000k tbc
  
  Unknown decoder 'libx264'
  
  simon@studio:~$ ffmpeg  -video_size 1280x720   -f x11grab  -i ${DISPLAY}+100,100  -vcodec libx264 -threads 0  ./video$(date +%F-%H-%M-%S).mp4
  
  ffmpeg version 3.4.6-0ubuntu0.18.04.1 Copyright (c) 2000-2019 the FFmpeg developers
  
    built with gcc 7 (Ubuntu 7.3.0-16ubuntu3)
  
    configuration: --prefix=/usr --extra-version=0ubuntu0.18.04.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  
    libavutil      55. 78.100 / 55. 78.100
  
    libavcodec     57.107.100 / 57.107.100
  
    libavformat    57. 83.100 / 57. 83.100
  
    libavdevice    57. 10.100 / 57. 10.100
  
    libavfilter     6.107.100 /  6.107.100
  
    libavresample   3.  7.  0 /  3.  7.  0
  
    libswscale      4.  8.100 /  4.  8.100
  
    libswresample   2.  9.100 /  2.  9.100
  
    libpostproc    54.  7.100 / 54.  7.100
  
  [x11grab @ 0x558225bc29a0] Stream #0: not enough frames to estimate rate; consider increasing probesize
  
  Input #0, x11grab, from ':0+100,100':
  
    Duration: N/A, start: 1578693132.513351, bitrate: N/A
  
      Stream #0:0: Video: rawvideo (BGR[0] / 0x524742), bgr0, 1280x720, 29.97 fps, 1000k tbr, 1000k tbn, 1000k tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
  
  Press [q] to stop, [?] for help
  
  [libx264 @ 0x558225bcd360] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2
  
  [libx264 @ 0x558225bcd360] profile High 4:4:4 Predictive, level 3.1, 4:4:4 8-bit
  
  [libx264 @ 0x558225bcd360] 264 - core 152 r2854 e9a5903 - H.264/MPEG-4 AVC codec - Copyleft 2003-2017 - 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=1 me_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=4 threads=6 lookahead_threads=1 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=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=1.40 aq=1:1.00
  
  Output #0, mp4, to './video2020-01-10-14-52-12.mp4':
  
    Metadata:
  
      encoder         : Lavf57.83.100
  
      Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv444p, 1280x720, q=-1--1, 29.97 fps, 30k tbn, 29.97 tbc
  
      Metadata:
  
        encoder         : Lavc57.107.100 libx264
  
      Side data:
  
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  
  Past duration 0.806847 too large     256kB time=00:00:00.43 bitrate=4835.3kbits/s dup=16 drop=0 speed=0.207x    
  
  frame=  371 fps= 29 q=-1.0 Lsize=     639kB time=00:00:12.27 bitrate= 426.6kbits/s dup=16 drop=14 speed=0.971x    
  
  video:634kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.813096%
  
  [libx264 @ 0x558225bcd360] frame I:2     Avg QP:18.16  size:221502
  
  [libx264 @ 0x558225bcd360] frame P:93    Avg QP:14.97  size:  2007
  
  [libx264 @ 0x558225bcd360] frame B:276   Avg QP:20.13  size:    69
  
  [libx264 @ 0x558225bcd360] consecutive B-frames:  0.8%  0.0%  0.0% 99.2%
  
  [libx264 @ 0x558225bcd360] mb I  I16..4: 44.6%  0.0% 55.4%
  
  [libx264 @ 0x558225bcd360] mb P  I16..4:  0.2%  0.0%  0.3%  P16..4:  0.7%  0.1%  0.1%  0.0%  0.0%    skip:98.5%
  
  [libx264 @ 0x558225bcd360] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  1.0%  0.0%  0.0%  direct: 0.0%  skip:99.0%  L0:50.9% L1:49.0% BI: 0.1%
  
  [libx264 @ 0x558225bcd360] coded y,u,v intra: 41.3% 37.5% 37.4% inter: 0.1% 0.0% 0.0%
  
  [libx264 @ 0x558225bcd360] i16 v,h,dc,p: 58% 41%  1%  0%
  
  [libx264 @ 0x558225bcd360] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 33% 30% 14%  2%  4%  4%  5%  3%  5%
  
  [libx264 @ 0x558225bcd360] Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 0x558225bcd360] ref P L0: 59.2%  8.8% 25.5%  6.5%
  
  [libx264 @ 0x558225bcd360] ref B L0: 59.4% 39.0%  1.6%
  
  [libx264 @ 0x558225bcd360] ref B L1: 96.5%  3.5%
  
  [libx264 @ 0x558225bcd360] kb/s:419.29
  
  Exiting normally, received signal 2.

• ffmpeg : corrupt audio in usage of avfoundation

  3 janvier 2016, par Andy

  I am trying to record my desktop screen (MacBook Pro (Retina, 15-inch, Mid 2014), OSX 10.10.5) with audio. First, I have to find the devices for recording, video:1 and audio:0 in my case.

  User@User-MacBook-Pro:~/test$ ffmpeg -hide_banner -f avfoundation -list_devices true -i ""
  
  [AVFoundation input device @ 0x7ff19a422320] AVFoundation video devices:
  
  [AVFoundation input device @ 0x7ff19a422320] [0] FaceTime HD Camera
  
  [AVFoundation input device @ 0x7ff19a422320] [1] Capture screen 0
  
  [AVFoundation input device @ 0x7ff4b9c22320] [2] Capture screen 1
  
  [AVFoundation input device @ 0x7ff19a422320] AVFoundation audio devices:
  
  [AVFoundation input device @ 0x7ff19a422320] [0] Soundflower (2ch)
  
  [AVFoundation input device @ 0x7ff19a422320] [1] Built-in Microphone
  
  [AVFoundation input device @ 0x7ff19a422320] [2] Soundflower (64ch)
  
  : Input/output error

  Then I run to capture the screen :

  ffmpeg -f avfoundation -i "1:0" out_desktop.mkv

  and the audio of the output stutters terribly.
  But if I use the second external screen (which is connect via HDMI) :

  ffmpeg -f avfoundation -i "2:0" out_ext.mkv

  Then I have no audio problems.

  So, what could be the cause of this behaviour ? Somehow the video device "Capture screen 0" causes the audio stutter.

  Here are the full outputs of the two commands above, Screen 0 :

  User@User-MacBook-Pro:~/test$ ffmpeg -f avfoundation -i "1:0" out.mkv
  
  ffmpeg version 2.8.4 Copyright (c) 2000-2015 the FFmpeg developers
  
    built with Apple LLVM version 7.0.2 (clang-700.1.81)
  
    configuration: --prefix=/usr/local/Cellar/ffmpeg/2.8.4 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-opencl --enable-libx264 --enable-libmp3lame --enable-libvo-aacenc --enable-libxvid --enable-libfreetype --enable-libtheora --enable-libvorbis --enable-libvpx --enable-librtmp --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libass --enable-ffplay --enable-libspeex --enable-libschroedinger --enable-libfdk-aac --enable-libopus --enable-frei0r --enable-libopenjpeg --disable-decoder=jpeg2000 --extra-cflags=-I/usr/local/Cellar/openjpeg/1.5.2_1/include/openjpeg-1.5 --enable-nonfree --enable-vda
  
    libavutil      54. 31.100 / 54. 31.100
  
    libavcodec     56. 60.100 / 56. 60.100
  
    libavformat    56. 40.101 / 56. 40.101
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 40.101 /  5. 40.101
  
    libavresample   2.  1.  0 /  2.  1.  0
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.101 /  1.  2.101
  
    libpostproc    53.  3.100 / 53.  3.100
  
  [avfoundation @ 0x7fca1200da00] Selected pixel format (yuv420p) is not supported by the input device.
  
  [avfoundation @ 0x7fca1200da00] Supported pixel formats:
  
  [avfoundation @ 0x7fca1200da00]   uyvy422
  
  [avfoundation @ 0x7fca1200da00]   yuyv422
  
  [avfoundation @ 0x7fca1200da00]   nv12
  
  [avfoundation @ 0x7fca1200da00]   0rgb
  
  [avfoundation @ 0x7fca1200da00]   bgr0
  
  [avfoundation @ 0x7fca1200da00] Overriding selected pixel format to use uyvy422 instead.
  
  [avfoundation @ 0x7fca1200da00] Stream #0: not enough frames to estimate rate; consider increasing probesize
  
  Input #0, avfoundation, from '1:0':
  
    Duration: N/A, start: 11734.092500, bitrate: 2822 kb/s
  
      Stream #0:0: Video: rawvideo (UYVY / 0x59565955), uyvy422, 2880x1800, 1000k tbr, 1000k tbn, 1000k tbc
  
      Stream #0:1: Audio: pcm_f32le, 44100 Hz, stereo, flt, 2822 kb/s
  
  File 'out.mkv' already exists. Overwrite ? [y/N] y
  
  No pixel format specified, yuv422p for H.264 encoding chosen.
  
  Use -pix_fmt yuv420p for compatibility with outdated media players.
  
  [libx264 @ 0x7fca1390e000] MB rate (20340000000) > level limit (2073600)
  
  [libx264 @ 0x7fca1390e000] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  
  [libx264 @ 0x7fca1390e000] profile High 4:2:2, level 5.2, 4:2:2 8-bit
  
  [libx264 @ 0x7fca1390e000] 264 - core 148 r2601 a0cd7d3 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=12 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=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=1.40 aq=1:1.00
  
  Output #0, matroska, to 'out.mkv':
  
    Metadata:
  
      encoder         : Lavf56.40.101
  
      Stream #0:0: Video: h264 (libx264) (H264 / 0x34363248), yuv422p, 2880x1800, q=-1--1, 1000k fps, 1k tbn, 1000k tbc
  
      Metadata:
  
        encoder         : Lavc56.60.100 libx264
  
      Stream #0:1: Audio: vorbis (libvorbis) (oV[0][0] / 0x566F), 44100 Hz, stereo, fltp
  
      Metadata:
  
        encoder         : Lavc56.60.100 libvorbis
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
  
    Stream #0:1 -> #0:1 (pcm_f32le (native) -> vorbis (libvorbis))
  
  Press [q] to stop, [?] for help
  
  frame=  969 fps= 29 q=-1.0 Lsize=    6911kB time=00:00:34.80 bitrate=1626.8kbits/s    
  
  video:6475kB audio:396kB subtitle:0kB other streams:0kB global headers:4kB muxing overhead: 0.591309%
  
  [libx264 @ 0x7fca1390e000] frame I:4     Avg QP:15.77  size:1461092
  
  [libx264 @ 0x7fca1390e000] frame P:246   Avg QP:16.00  size:  2608
  
  [libx264 @ 0x7fca1390e000] frame B:719   Avg QP:13.91  size:   200
  
  [libx264 @ 0x7fca1390e000] consecutive B-frames:  0.9%  0.4%  0.0% 98.7%
  
  [libx264 @ 0x7fca1390e000] mb I  I16..4: 11.6% 43.3% 45.2%
  
  [libx264 @ 0x7fca1390e000] mb P  I16..4:  0.0%  0.0%  0.1%  P16..4:  0.4%  0.0%  0.0%  0.0%  0.0%    skip:99.5%
  
  [libx264 @ 0x7fca1390e000] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  0.2%  0.0%  0.0%  direct: 0.0%  skip:99.8%  L0:39.9% L1:60.0% BI: 0.1%
  
  [libx264 @ 0x7fca1390e000] 8x8 transform intra:41.6% inter:38.8%
  
  [libx264 @ 0x7fca1390e000] coded y,uvDC,uvAC intra: 76.9% 77.9% 75.5% inter: 0.0% 0.1% 0.0%
  
  [libx264 @ 0x7fca1390e000] i16 v,h,dc,p: 51% 34% 11%  4%
  
  [libx264 @ 0x7fca1390e000] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 22% 17% 19%  7%  4%  3%  8%  5% 16%
  
  [libx264 @ 0x7fca1390e000] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 21% 24% 10%  7%  6%  5%  8%  7% 12%
  
  [libx264 @ 0x7fca1390e000] i8c dc,h,v,p: 59% 14% 18%  9%
  
  [libx264 @ 0x7fca1390e000] Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 0x7fca1390e000] ref P L0: 71.5%  3.4% 13.0% 12.1%
  
  [libx264 @ 0x7fca1390e000] ref B L0: 46.6% 52.3%  1.1%
  
  [libx264 @ 0x7fca1390e000] ref B L1: 95.1%  4.9%
  
  [libx264 @ 0x7fca1390e000] kb/s:1525.48

  and Screen 1 :

  User@User-MacBook-Pro:~/test$ ffmpeg -f avfoundation -i "2:0" out.mkv
  
  ffmpeg version 2.8.4 Copyright (c) 2000-2015 the FFmpeg developers
  
    built with Apple LLVM version 7.0.2 (clang-700.1.81)
  
    configuration: --prefix=/usr/local/Cellar/ffmpeg/2.8.4 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-opencl --enable-libx264 --enable-libmp3lame --enable-libvo-aacenc --enable-libxvid --enable-libfreetype --enable-libtheora --enable-libvorbis --enable-libvpx --enable-librtmp --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libass --enable-ffplay --enable-libspeex --enable-libschroedinger --enable-libfdk-aac --enable-libopus --enable-frei0r --enable-libopenjpeg --disable-decoder=jpeg2000 --extra-cflags=-I/usr/local/Cellar/openjpeg/1.5.2_1/include/openjpeg-1.5 --enable-nonfree --enable-vda
  
    libavutil      54. 31.100 / 54. 31.100
  
    libavcodec     56. 60.100 / 56. 60.100
  
    libavformat    56. 40.101 / 56. 40.101
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 40.101 /  5. 40.101
  
    libavresample   2.  1.  0 /  2.  1.  0
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.101 /  1.  2.101
  
    libpostproc    53.  3.100 / 53.  3.100
  
  [avfoundation @ 0x7fc2e900da00] Selected pixel format (yuv420p) is not supported by the input device.
  
  [avfoundation @ 0x7fc2e900da00] Supported pixel formats:
  
  [avfoundation @ 0x7fc2e900da00]   uyvy422
  
  [avfoundation @ 0x7fc2e900da00]   yuyv422
  
  [avfoundation @ 0x7fc2e900da00]   nv12
  
  [avfoundation @ 0x7fc2e900da00]   0rgb
  
  [avfoundation @ 0x7fc2e900da00]   bgr0
  
  [avfoundation @ 0x7fc2e900da00] Overriding selected pixel format to use uyvy422 instead.
  
  [avfoundation @ 0x7fc2e900da00] Stream #0: not enough frames to estimate rate; consider increasing probesize
  
  Input #0, avfoundation, from '2:0':
  
    Duration: N/A, start: 11809.126333, bitrate: 2822 kb/s
  
      Stream #0:0: Video: rawvideo (UYVY / 0x59565955), uyvy422, 2560x1080, 1000k tbr, 1000k tbn, 1000k tbc
  
      Stream #0:1: Audio: pcm_f32le, 44100 Hz, stereo, flt, 2822 kb/s
  
  File 'out.mkv' already exists. Overwrite ? [y/N] y
  
  No pixel format specified, yuv422p for H.264 encoding chosen.
  
  Use -pix_fmt yuv420p for compatibility with outdated media players.
  
  [libx264 @ 0x7fc2ea82ac00] MB rate (10880000000) > level limit (2073600)
  
  [libx264 @ 0x7fc2ea82ac00] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  
  [libx264 @ 0x7fc2ea82ac00] profile High 4:2:2, level 5.2, 4:2:2 8-bit
  
  [libx264 @ 0x7fc2ea82ac00] 264 - core 148 r2601 a0cd7d3 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=12 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=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=1.40 aq=1:1.00
  
  Output #0, matroska, to 'out.mkv':
  
    Metadata:
  
      encoder         : Lavf56.40.101
  
      Stream #0:0: Video: h264 (libx264) (H264 / 0x34363248), yuv422p, 2560x1080, q=-1--1, 1000k fps, 1k tbn, 1000k tbc
  
      Metadata:
  
        encoder         : Lavc56.60.100 libx264
  
      Stream #0:1: Audio: vorbis (libvorbis) (oV[0][0] / 0x566F), 44100 Hz, stereo, fltp
  
      Metadata:
  
        encoder         : Lavc56.60.100 libvorbis
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
  
    Stream #0:1 -> #0:1 (pcm_f32le (native) -> vorbis (libvorbis))
  
  Press [q] to stop, [?] for help
  
  frame=  755 fps= 30 q=-1.0 Lsize=    1025kB time=00:00:26.65 bitrate= 315.1kbits/s    
  
  video:680kB audio:326kB subtitle:0kB other streams:0kB global headers:4kB muxing overhead: 2.003084%
  
  [libx264 @ 0x7fc2ea82ac00] frame I:4     Avg QP:13.22  size:145661
  
  [libx264 @ 0x7fc2ea82ac00] frame P:191   Avg QP:19.87  size:   250
  
  [libx264 @ 0x7fc2ea82ac00] frame B:560   Avg QP:28.31  size:   116
  
  [libx264 @ 0x7fc2ea82ac00] consecutive B-frames:  1.1%  0.0%  0.4% 98.5%
  
  [libx264 @ 0x7fc2ea82ac00] mb I  I16..4: 54.5% 29.2% 16.2%
  
  [libx264 @ 0x7fc2ea82ac00] mb P  I16..4:  0.2%  0.1%  0.0%  P16..4:  0.1%  0.0%  0.0%  0.0%  0.0%    skip:99.6%
  
  [libx264 @ 0x7fc2ea82ac00] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  0.3%  0.0%  0.0%  direct: 0.0%  skip:99.7%  L0:69.2% L1:30.8% BI: 0.0%
  
  [libx264 @ 0x7fc2ea82ac00] 8x8 transform intra:31.7% inter:13.1%
  
  [libx264 @ 0x7fc2ea82ac00] coded y,uvDC,uvAC intra: 10.9% 8.8% 8.5% inter: 0.0% 0.0% 0.0%
  
  [libx264 @ 0x7fc2ea82ac00] i16 v,h,dc,p: 69% 31%  0%  0%
  
  [libx264 @ 0x7fc2ea82ac00] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 27%  5% 67%  0%  0%  0%  0%  0%  0%
  
  [libx264 @ 0x7fc2ea82ac00] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 38% 25% 14%  3%  3%  4%  5%  4%  5%
  
  [libx264 @ 0x7fc2ea82ac00] i8c dc,h,v,p: 92%  3%  4%  0%
  
  [libx264 @ 0x7fc2ea82ac00] Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 0x7fc2ea82ac00] ref P L0: 76.3%  1.7% 16.8%  5.2%
  
  [libx264 @ 0x7fc2ea82ac00] ref B L0: 38.9% 56.9%  4.2%
  
  [libx264 @ 0x7fc2ea82ac00] ref B L1: 97.3%  2.7%
  
  [libx264 @ 0x7fc2ea82ac00] kb/s:208.84

  EDIT

  The main differences between the two (lengthy) outputs above via

  wdiff -n output1 output2 |colordiff

  is the resolution ([-2880x1800,-] {+2560x1080,+}) and the resulting MB rate ([-(20340000000)-] {+(10880000000)+}). So, what could increase the performance of ffmpeg ?