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    13 mai 2011, par

    Dixit Wikipedia, XMP signifie :
    Extensible Metadata Platform ou XMP est un format de métadonnées basé sur XML utilisé dans les applications PDF, de photographie et de graphisme. Il a été lancé par Adobe Systems en avril 2001 en étant intégré à la version 5.0 d’Adobe Acrobat.
    Étant basé sur XML, il gère un ensemble de tags dynamiques pour l’utilisation dans le cadre du Web sémantique.
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    18 février 2011, par

    Multilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
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    8 février 2011, par

    Par défaut, beaucoup de fonctionnalités sont limitées aux administrateurs mais restent configurables indépendamment pour modifier leur statut minimal d’utilisation notamment : la rédaction de contenus sur le site modifiables dans la gestion des templates de formulaires ; l’ajout de notes aux articles ; l’ajout de légendes et d’annotations sur les images ;

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  • How to stream live-video display from a webcam using FFMPEG command on tcl version 8.0 and windows 7 ?

    27 juin 2019, par M. D. P

    I am working on project were i need to have the live video streaming.
    I am able to save the video using the command :

    proc a {}  {
    exec ffmpeg -f dshow -rtbufsize 64M -i "video=Integrated Webcam" -s 1280x720 -f sdl2 -
    }
    a

    this is the current error:
    ffmpeg started on 2017-11-17 at 15:24:45
    Report written to "ffmpeg-20171117-152445.log"
    Command line:
    ffmpeg -f dshow -report -rtbufsize 64M -i "video=Integrated Webcam" -s 1280x720 -f sdl2 -
    ffmpeg version N-87353-g183fd30 Copyright (c) 2000-2017 the FFmpeg developers
     built with gcc 7.2.0 (GCC)
     configuration: --enable-gpl --enable-version3 --enable-cuda --enable-cuvid --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib
     libavutil      55. 76.100 / 55. 76.100
     libavcodec     57.106.101 / 57.106.101
     libavformat    57. 82.101 / 57. 82.101
     libavdevice    57.  8.101 / 57.  8.101
     libavfilter     6.105.100 /  6.105.100
     libswscale      4.  7.103 /  4.  7.103
     libswresample   2.  8.100 /  2.  8.100
     libpostproc    54.  6.100 / 54.  6.100
    Splitting the commandline.
    Reading option '-f' ... matched as option 'f' (force format) with argument 'dshow'.
    Reading option '-report' ... matched as option 'report' (generate a report) with argument '1'.
    Reading option '-rtbufsize' ... matched as AVOption 'rtbufsize' with argument '64M'.
    Reading option '-i' ... matched as input url with argument 'video=Integrated Webcam'.
    Reading option '-s' ... matched as option 's' (set frame size (WxH or abbreviation)) with argument '1280x720'.
    Reading option '-f' ... matched as option 'f' (force format) with argument 'sdl2'.
    Reading option '-' ... matched as output url.
    Finished splitting the commandline.
    Parsing a group of options: global .
    Applying option report (generate a report) with argument 1.
    Successfully parsed a group of options.
    Parsing a group of options: input url video=Integrated Webcam.
    Applying option f (force format) with argument dshow.
    Successfully parsed a group of options.
    Opening an input file: video=Integrated Webcam.
    [dshow @ 0000000000e06a40] Selecting pin Capture on video
    dshow passing through packet of type video size   614400 timestamp 5773900280000 orig timestamp 5773900274254 graph timestamp 5773900280000 diff 5746 Integrated Webcam
    [dshow @ 0000000000e06a40] All info found
    Input #0, dshow, from 'video=Integrated Webcam':
     Duration: N/A, start: 577390.028000, bitrate: N/A
       Stream #0:0, 1, 1/10000000: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 640x480, 30 fps, 30 tbr, 10000k tbn, 10000k tbc
    Successfully opened the file.
    Parsing a group of options: output url -.
    Applying option s (set frame size (WxH or abbreviation)) with argument 1280x720.
    Applying option f (force format) with argument sdl2.
    Successfully parsed a group of options.
    Opening an output file: -.
    Successfully opened the file.
    Stream mapping:
     Stream #0:0 -> #0:0 (rawvideo (native) -> rawvideo (native))
    Press [q] to stop, [?] for help
    cur_dts is invalid (this is harmless if it occurs once at the start per stream)
    [rawvideo @ 0000000000d90be0] PACKET SIZE: 614400, STRIDE: 1280
    detected 4 logical cores
    dshow passing through packet of type video size   614400 timestamp 5773900600000 orig timestamp 5773900607587 graph timestamp 5773900600000 diff -7587 Integrated Webcam
    [graph 0 input from stream 0:0 @ 0000000000d96200] Setting 'video_size' to value '640x480'
    [graph 0 input from stream 0:0 @ 0000000000d96200] Setting 'pix_fmt' to value '1'
    [graph 0 input from stream 0:0 @ 0000000000d96200] Setting 'time_base' to value '1/10000000'
    [graph 0 input from stream 0:0 @ 0000000000d96200] Setting 'pixel_aspect' to value '0/1'
    [graph 0 input from stream 0:0 @ 0000000000d96200] Setting 'sws_param' to value 'flags=2'
    [graph 0 input from stream 0:0 @ 0000000000d96200] Setting 'frame_rate' to value '10000000/333333'
    [graph 0 input from stream 0:0 @ 0000000000d96200] w:640 h:480 pixfmt:yuyv422 tb:1/10000000 fr:10000000/333333 sar:0/1 sws_param:flags=2
    [scaler_out_0_0 @ 0000000000d967e0] Setting 'w' to value '1280'
    [scaler_out_0_0 @ 0000000000d967e0] Setting 'h' to value '720'
    [scaler_out_0_0 @ 0000000000d967e0] Setting 'flags' to value 'bicubic'
    [scaler_out_0_0 @ 0000000000d967e0] w:1280 h:720 flags:'bicubic' interl:0
    [AVFilterGraph @ 0000000000d94d40] query_formats: 4 queried, 3 merged, 0 already done, 0 delayed
    [scaler_out_0_0 @ 0000000000d967e0] w:640 h:480 fmt:yuyv422 sar:0/1 -> w:1280 h:720 fmt:yuyv422 sar:0/1 flags:0x4
    dshow passing through packet of type video size   614400 timestamp 5773900970000 orig timestamp 5773900940920 graph timestamp 5773900970000 diff 29080 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773901240000 orig timestamp 5773901274253 graph timestamp 5773901240000 diff -34253 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773901720000 orig timestamp 5773901607586 graph timestamp 5773901720000 diff 112414 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773902040000 orig timestamp 5773901940919 graph timestamp 5773902040000 diff 99081 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773902360000 orig timestamp 5773902274252 graph timestamp 5773902360000 diff 85748 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773902680000 orig timestamp 5773902607585 graph timestamp 5773902680000 diff 72415 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773903000000 orig timestamp 5773902940918 graph timestamp 5773903000000 diff 59082 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773903320000 orig timestamp 5773903274251 graph timestamp 5773903320000 diff 45749 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773903640000 orig timestamp 5773903607584 graph timestamp 5773903640000 diff 32416 Integrated Webcam
    [sdl,sdl2 @ 0000000000d911c0] w:1280 h:720 fmt:yuyv422 -> w:1280 h:720
    Output #0, sdl,sdl2, to 'pipe:':
     Metadata:
       encoder         : Lavf57.82.101
       Stream #0:0, 0, 333333/10000000: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 1280x720, q=2-31, 442368 kb/s, 30 fps, 30 tbn, 30 tbc
       Metadata:
         encoder         : Lavc57.106.101 rawvideo
    dshow passing through packet of type video size   614400 timestamp 5773903970000 orig timestamp 5773903940917 graph timestamp 5773903970000 diff 29083 Integrated Webcam
    dshow passing through packet of type video size   614400 timestamp 5773904280000 orig timestamp 5773904274250 graph timestamp 5773904280000 diff 5750 Integrated Webcam
    av_interleaved_write_frame(): Operation not permitted
    No more output streams to write to, finishing.
    dshow passing through packet of type video size   614400 timestamp 5773904660000 orig timestamp 5773904607583 graph timestamp 5773904660000 diff 52417 Integrated Webcam
    frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.03 bitrate=N/A speed=0.0797x    
    video:1800kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
    Input file #0 (video=Integrated Webcam):
     Input stream #0:0 (video): 1 packets read (614400 bytes); 1 frames decoded;
     Total: 1 packets (614400 bytes) demuxed
    Output file #0 (pipe:):
     Output stream #0:0 (video): 1 frames encoded; 1 packets muxed (1843200 bytes);
     Total: 1 packets (1843200 bytes) muxed
    1 frames successfully decoded, 0 decoding errors
    dshow passing through packet of type video size        0 timestamp 5773907070000 orig timestamp 2644601806342528 graph timestamp 5773907070000 diff -2638827899272528 Integrated Webcam
    Conversion failed!
    % source c:/other/a/d.tcl
    couldn't execute "ffmpeg -f dshow -t 00:00:10 -i {video=Integrated Webcam} -b 5000k -s 1280x720 c:\test\sample-a.avi": no such file or directory
    % source c:/other/a/d.tcl
    invalid command name "ffmpeg"
    % source c:/other/a/d.tcl
    ffmpeg version N-87353-g183fd30 Copyright (c) 2000-2017 the FFmpeg developers
     built with gcc 7.2.0 (GCC)
     configuration: --enable-gpl --enable-version3 --enable-cuda --enable-cuvid --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib
     libavutil      55. 76.100 / 55. 76.100
     libavcodec     57.106.101 / 57.106.101
     libavformat    57. 82.101 / 57. 82.101
     libavdevice    57.  8.101 / 57.  8.101
     libavfilter     6.105.100 /  6.105.100
     libswscale      4.  7.103 /  4.  7.103
     libswresample   2.  8.100 /  2.  8.100
     libpostproc    54.  6.100 / 54.  6.100
    Input #0, dshow, from 'video=Integrated Webcam':
     Duration: N/A, start: 523220.045000, bitrate: N/A
       Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 640x480, 30 fps, 30 tbr, 10000k tbn, 10000k tbc
    Stream mapping:
     Stream #0:0 -> #0:0 (rawvideo (native) -> rawvideo (native))
    Press [q] to stop, [?] for help
    Output #0, sdl,sdl2, to 'pipe:':
     Metadata:
       encoder         : Lavf57.82.101
       Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 1280x720, q=2-31, 442368 kb/s, 30 fps, 30 tbn, 30 tbc
       Metadata:
         encoder         : Lavc57.106.101 rawvideo
    av_interleaved_write_frame(): Operation not permitted
    frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.03 bitrate=N/A speed=0.0471x
    video:1800kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
    Conversion failed!
    %

    But, the problem is i don’t want to save the video, I just want to have live video streaming.

    link : https://trac.ffmpeg.org/wiki/StreamingGuide, provide the command for live video streaming, but it want work, the webcem gets started, but live video streaming is not displayed on screen.

    so, can any one help me out to get right "FFMPEG" command or even any TCL script, to get the live video streaming displayed on on my windows 7.

    ffplay started on 2017-11-17 at 12:44:40
    Report written to "ffplay-20171117-124440.log"
    Command line:
    ffplay -report C:/test/sample.avi
    ffplay version N-87353-g183fd30 Copyright (c) 2003-2017 the FFmpeg developers
     built with gcc 7.2.0 (GCC)
     configuration: --enable-gpl --enable-version3 --enable-cuda --enable-cuvid --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib
     libavutil      55. 76.100 / 55. 76.100
     libavcodec     57.106.101 / 57.106.101
     libavformat    57. 82.101 / 57. 82.101
     libavdevice    57.  8.101 / 57.  8.101
     libavfilter     6.105.100 /  6.105.100
     libswscale      4.  7.103 /  4.  7.103
     libswresample   2.  8.100 /  2.  8.100
     libpostproc    54.  6.100 / 54.  6.100
       nan    :  0.000 fd=   0 aq=    0KB vq=    0KB sq=    0B f=0/0  
    [NULL @ 0000000002aea040] Opening 'C:/test/sample.avi' for reading
    [file @ 0000000002ae9c80] Setting default whitelist 'file,crypto'
    [avi @ 0000000002aea040] Format avi probed with size=2048 and score=100
    [avi @ 0000000002af30c0] use odml:1
    [avi @ 0000000002aea040] Before avformat_find_stream_info() pos: 5678 bytes read:107912 seeks:4 nb_streams:1
    [avi @ 0000000002aea040] All info found
    [avi @ 0000000002aea040] After avformat_find_stream_info() pos: 33035 bytes read:107912 seeks:4 frames:1
    Input #0, avi, from 'C:/test/sample.avi':
     Metadata:
       encoder         : Lavf57.82.101
     Duration: 00:00:10.00, start: 0.000000, bitrate: 5072 kb/s
       Stream #0:0, 1, 1/30: Video: mpeg4 (Simple Profile) (FMP4 / 0x34504D46), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 5078 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
    detected 4 logical cores
       nan M-V:    nan fd=   0 aq=    0KB vq=  595KB sq=    0B f=0/0  
    Video frame changed from size:0x0 format:none serial:-1 to size:1280x720 format:yuv420p serial:1
    [ffplay_buffer @ 0000000003a17ee0] Setting 'video_size' to value '1280x720'
    [ffplay_buffer @ 0000000003a17ee0] Setting 'pix_fmt' to value '0'
    [ffplay_buffer @ 0000000003a17ee0] Setting 'time_base' to value '1/30'
    [ffplay_buffer @ 0000000003a17ee0] Setting 'pixel_aspect' to value '1/1'
    [ffplay_buffer @ 0000000003a17ee0] Setting 'frame_rate' to value '30/1'
    [ffplay_buffer @ 0000000003a17ee0] w:1280 h:720 pixfmt:yuv420p tb:1/30 fr:30/1 sar:1/1 sws_param:
    [AVFilterGraph @ 0000000002b14fc0] query_formats: 2 queried, 1 merged, 0 already done, 0 delayed
  • How to get .mp4 videos from motion on a Raspberry Pi ?

    3 novembre 2017, par Maarti

    I use motion on my laptop and it works perfectly in any format. But when I use it on my Raspberry Pi 3 (Raspbian Jessie) with the Raspberry Camera V2, the only formats that work are : .avi and .swf.

    When I choose any other format, the output video is a "0 sec video" that is played and closed instantly.

    I would like to have .mp4 or .ogg output so I can read it easily with HTML5.

    Here is the motion codec documentation.

    Here is my config file :

    ############################################################
    # Daemon
    ############################################################

    # Start in daemon (background) mode and release terminal (default: off)
    daemon on

    # File to store the process ID, also called pid file. (default: not defined)
    process_id_file /var/run/motion/motion.pid

    ############################################################
    # Basic Setup Mode
    ############################################################

    # Start in Setup-Mode, daemon disabled. (default: off)
    setup_mode off


    # Use a file to save logs messages, if not defined stderr and syslog is used. (default: not defined)
    #logfile /mnt/camshare/Cam1/motion.log
    logfile /tmp/motion.log

    # Level of log messages [1..9] (EMR, ALR, CRT, ERR, WRN, NTC, INF, DBG, ALL). (default: 6 / NTC)
    log_level 2

    # Filter to log messages by type (COR, STR, ENC, NET, DBL, EVT, TRK, VID, ALL). (default: ALL)
    log_type all

    ###########################################################
    # Capture device options
    ############################################################

    # Videodevice to be used for capturing  (default /dev/video0)
    # for FreeBSD default is /dev/bktr0
    #videodevice /dev/video0

    # v4l2_palette allows to choose preferable palette to be use by motion
    # to capture from those supported by your videodevice. (default: 17)
    # E.g. if your videodevice supports both V4L2_PIX_FMT_SBGGR8 and
    # V4L2_PIX_FMT_MJPEG then motion will by default use V4L2_PIX_FMT_MJPEG.
    # Setting v4l2_palette to 2 forces motion to use V4L2_PIX_FMT_SBGGR8
    # instead.
    #
    # Values :
    # V4L2_PIX_FMT_SN9C10X : 0  'S910'
    # V4L2_PIX_FMT_SBGGR16 : 1  'BYR2'
    # V4L2_PIX_FMT_SBGGR8  : 2  'BA81'
    # V4L2_PIX_FMT_SPCA561 : 3  'S561'
    # V4L2_PIX_FMT_SGBRG8  : 4  'GBRG'
    # V4L2_PIX_FMT_SGRBG8  : 5  'GRBG'
    # V4L2_PIX_FMT_PAC207  : 6  'P207'
    # V4L2_PIX_FMT_PJPG    : 7  'PJPG'
    # V4L2_PIX_FMT_MJPEG   : 8  'MJPEG'
    # V4L2_PIX_FMT_JPEG    : 9  'JPEG'
    # V4L2_PIX_FMT_RGB24   : 10 'RGB3'
    # V4L2_PIX_FMT_SPCA501 : 11 'S501'
    # V4L2_PIX_FMT_SPCA505 : 12 'S505'
    # V4L2_PIX_FMT_SPCA508 : 13 'S508'
    # V4L2_PIX_FMT_UYVY    : 14 'UYVY'
    # V4L2_PIX_FMT_YUYV    : 15 'YUYV'
    # V4L2_PIX_FMT_YUV422P : 16 '422P'
    # V4L2_PIX_FMT_YUV420  : 17 'YU12'
    #
    v4l2_palette 7

    # Tuner device to be used for capturing using tuner as source (default /dev/tuner0)
    # This is ONLY used for FreeBSD. Leave it commented out for Linux
    ; tunerdevice /dev/tuner0

    # The video input to be used (default: -1)
    # Should normally be set to 0 or 1 for video/TV cards, and -1 for USB cameras
    input -1

    # The video norm to use (only for video capture and TV tuner cards)
    # Values: 0 (PAL), 1 (NTSC), 2 (SECAM), 3 (PAL NC no colour). Default: 0 (PAL)
    norm 0

    # The frequency to set the tuner to (kHz) (only for TV tuner cards) (default: 0)
    frequency 0

    # Rotate image this number of degrees. The rotation affects all saved images as
    # well as movies. Valid values: 0 (default = no rotation), 90, 180 and 270.
    rotate 0

    # Image width (pixels). Valid range: Camera dependent, default: 352
    #width 1024
    width 640

    # Image height (pixels). Valid range: Camera dependent, default: 288
    #height 576
    height 480

    # Maximum number of frames to be captured per second.
    # Valid range: 2-100. Default: 100 (almost no limit).
    framerate 15

    # Minimum time in seconds between capturing picture frames from the camera.
    # Default: 0 = disabled - the capture rate is given by the camera framerate.
    # This option is used when you want to capture images at a rate lower than 2 per second.
    minimum_frame_time 0

    # URL to use if you are using a network camera, size will be autodetected (incl http:// ftp:// mjpg:// or file:///)
    # Must be a URL that returns single jpeg pictures or a raw mjpeg stream. Default: Not defined
    ;netcam_url http://127.0.0.1/cgi-bin/raspicam.sh

    # Username and password for network camera (only if required). Default: not defined
    # Syntax is user:password
    ; netcam_userpass value

    # The setting for keep-alive of network socket, should improve performance on compatible net cameras.
    # off:   The historical implementation using HTTP/1.0, closing the socket after each http request.
    # force: Use HTTP/1.0 requests with keep alive header to reuse the same connection.
    # on:    Use HTTP/1.1 requests that support keep alive as default.
    # Default: off
    netcam_keepalive off

    # URL to use for a netcam proxy server, if required, e.g. "http://myproxy".
    # If a port number other than 80 is needed, use "http://myproxy:1234".
    # Default: not defined
    ; netcam_proxy value

    # Set less strict jpeg checks for network cameras with a poor/buggy firmware.
    # Default: off
    netcam_tolerant_check off

    # Let motion regulate the brightness of a video device (default: off).
    # The auto_brightness feature uses the brightness option as its target value.
    # If brightness is zero auto_brightness will adjust to average brightness value 128.
    # Only recommended for cameras without auto brightness
    auto_brightness off

    # Set the initial brightness of a video device.
    # If auto_brightness is enabled, this value defines the average brightness level
    # which Motion will try and adjust to.
    # Valid range 0-255, default 0 = disabled
    brightness 0

    # Set the contrast of a video device.
    # Valid range 0-255, default 0 = disabled
    contrast 0

    # Set the saturation of a video device.
    # Valid range 0-255, default 0 = disabled
    saturation 0

    # Set the hue of a video device (NTSC feature).
    # Valid range 0-255, default 0 = disabled
    hue 0

    ############################################################
    # File "camera" support - read raw YUV data from a file
    ############################################################
    #filecam_path /home/pi/test-cap/motion-mmal.capture

    ############################################################
    # OpenMax/MMAL camera support for Raspberry Pi
    ############################################################
    mmalcam_name vc.ril.camera
    #mmalcam_control_params
    #mmalcam_raw_capture_file /home/pi/motion-mmal.capture

    # Switch this setting to "on" to use the still image mode of the Pi's camera
    # instead of video. This gives a wider field of view, but requires
    # a much slower frame-rate to achieve exposure stability
    # (e.g. 0.25 fps or slower). You can use the minimum_frame_time
    # parameter above to achieve this

    mmalcam_use_still off


    ############################################################
    # Round Robin (multiple inputs on same video device name)
    ############################################################

    # Number of frames to capture in each roundrobin step (default: 1)
    roundrobin_frames 1

    # Number of frames to skip before each roundrobin step (default: 1)
    roundrobin_skip 1

    # Try to filter out noise generated by roundrobin (default: off)
    switchfilter off


    ############################################################
    # Motion Detection Settings:
    ############################################################

    # Threshold for number of changed pixels in an image that
    # triggers motion detection (default: 1500)
    threshold 1500

    # Automatically tune the threshold down if possible (default: off)
    threshold_tune off

    # Noise threshold for the motion detection (default: 32)
    noise_level 32

    # Automatically tune the noise threshold (default: on)
    noise_tune on

    # Despeckle motion image using (e)rode or (d)ilate or (l)abel (Default: not defined)
    # Recommended value is EedDl. Any combination (and number of) of E, e, d, and D is valid.
    # (l)abeling must only be used once and the 'l' must be the last letter.
    # Comment out to disable
    despeckle_filter EedDl

    # Detect motion in predefined areas (1 - 9). Areas are numbered like that:  1 2 3
    # A script (on_area_detected) is started immediately when motion is         4 5 6
    # detected in one of the given areas, but only once during an event.        7 8 9
    # One or more areas can be specified with this option. Take care: This option
    # does NOT restrict detection to these areas! (Default: not defined)
    ; area_detect value

    # PGM file to use as a sensitivity mask.
    # Full path name to. (Default: not defined)
    ; mask_file value

    # Dynamically create a mask file during operation (default: 0)
    # Adjust speed of mask changes from 0 (off) to 10 (fast)
    smart_mask_speed 0

    # Ignore sudden massive light intensity changes given as a percentage of the picture
    # area that changed intensity. Valid range: 0 - 100 , default: 0 = disabled
    lightswitch 0

    # Picture frames must contain motion at least the specified number of frames
    # in a row before they are detected as true motion. At the default of 1, all
    # motion is detected. Valid range: 1 to thousands, recommended 1-5
    minimum_motion_frames 1

    # Specifies the number of pre-captured (buffered) pictures from before motion
    # was detected that will be output at motion detection.
    # Recommended range: 0 to 5 (default: 0)
    # Do not use large values! Large values will cause Motion to skip video frames and
    # cause unsmooth movies. To smooth movies use larger values of post_capture instead.
    pre_capture 2

    # Number of frames to capture after motion is no longer detected (default: 0)
    post_capture 2

    # Event Gap is the seconds of no motion detection that triggers the end of an event.
    # An event is defined as a series of motion images taken within a short timeframe.
    # Recommended value is 60 seconds (Default). The value -1 is allowed and disables
    # events causing all Motion to be written to one single movie file and no pre_capture.
    # If set to 0, motion is running in gapless mode. Movies don't have gaps anymore. An
    # event ends right after no more motion is detected and post_capture is over.
    event_gap 60

    # Maximum length in seconds of an mpeg movie
    # When value is exceeded a new movie file is created. (Default: 0 = infinite)
    # ATTENTION: when you're not using the motion build from the tutorial, it might fail with error 'Unknown config option "max_mpeg_time"'
    # the use this line instead:
    # max_movie_time 60
    max_movie_time 60

    # Always save images even if there was no motion (default: off)
    emulate_motion off


    ############################################################
    # Image File Output
    ############################################################

    # Output 'normal' pictures when motion is detected (default: on)
    # Valid values: on, off, first, best, center
    # When set to 'first', only the first picture of an event is saved.
    # Picture with most motion of an event is saved when set to 'best'.
    # Picture with motion nearest center of picture is saved when set to 'center'.
    # Can be used as preview shot for the corresponding movie.
    output_pictures best

    # Output pictures with only the pixels moving object (ghost images) (default: off)
    output_debug_pictures off

    # The quality (in percent) to be used by the jpeg compression (default: 75)
    quality 75

    # Type of output images
    # Valid values: jpeg, ppm (default: jpeg)
    picture_type jpeg

    ############################################################
    # FFMPEG related options
    # Film (movies) file output, and deinterlacing of the video input
    # The options movie_filename and timelapse_filename are also used
    # by the ffmpeg feature
    ############################################################

    # Use ffmpeg to encode movies in realtime (default: off)
    ffmpeg_output_movies on

    # Use ffmpeg to make movies with only the pixels moving
    # object (ghost images) (default: off)
    ffmpeg_output_debug_movies off

    # Use ffmpeg to encode a timelapse movie
    # Default value 0 = off - else save frame every Nth second
    ffmpeg_timelapse 0

    # The file rollover mode of the timelapse video
    # Valid values: hourly, daily (default), weekly-sunday, weekly-monday, monthly, manual
    ffmpeg_timelapse_mode daily

    # Bitrate to be used by the ffmpeg encoder (default: 400000)
    # This option is ignored if ffmpeg_variable_bitrate is not 0 (disabled)
    ffmpeg_bps 500000

    # Enables and defines variable bitrate for the ffmpeg encoder.
    # ffmpeg_bps is ignored if variable bitrate is enabled.
    # Valid values: 0 (default) = fixed bitrate defined by ffmpeg_bps,
    # or the range 2 - 31 where 2 means best quality and 31 is worst.
    ffmpeg_variable_bitrate 5

    # Codec to used by ffmpeg for the video compression.
    # Timelapse mpegs are always made in mpeg1 format independent from this option.
    # Supported formats are: mpeg1 (ffmpeg-0.4.8 only), mpeg4 (default), and msmpeg4.
    # mpeg1 - gives you files with extension .mpg
    # mpeg4 or msmpeg4 - gives you files with extension .avi
    # msmpeg4 is recommended for use with Windows Media Player because
    # it requires no installation of codec on the Windows client.
    # swf - gives you a flash film with extension .swf
    # flv - gives you a flash video with extension .flv
    # ffv1 - FF video codec 1 for Lossless Encoding ( experimental )
    # mov - QuickTime ( testing )
    # ogg - Ogg/Theora ( testing )
    #ffmpeg_video_codec msmpeg4
    ffmpeg_video_codec mp4

    # Use ffmpeg to deinterlace video. Necessary if you use an analog camera
    # and see horizontal combing on moving objects in video or pictures.
    # (default: off)
    ffmpeg_deinterlace off

    ############################################################
    # SDL Window
    ############################################################

    # Number of motion thread to show in SDL Window (default: 0 = disabled)
    #sdl_threadnr 0

    ############################################################
    # External pipe to video encoder
    # Replacement for FFMPEG builtin encoder for ffmpeg_output_movies only.
    # The options movie_filename and timelapse_filename are also used
    # by the ffmpeg feature
    #############################################################

    # Bool to enable or disable extpipe (default: off)
    use_extpipe off

    # External program (full path and opts) to pipe raw video to
    # Generally, use '-' for STDIN...
    ;extpipe mencoder -demuxer rawvideo -rawvideo w=320:h=240:i420 -ovc x264 -x264encopts bframes=4:frameref=1:subq=1:scenecut=-1:nob_adapt:threads=1:keyint=1000:8x8dct:vbv_bufsize=4000:crf=24:partitions=i8x8,i4x4:vbv_maxrate=800:no-chroma-me -vf denoise3d=16:12:48:4,pp=lb -of   avi -o %f.avi - -fps %fps



    ############################################################
    # Snapshots (Traditional Periodic Webcam File Output)
    ############################################################

    # Make automated snapshot every N seconds (default: 0 = disabled)
    snapshot_interval 0


    ############################################################
    # Text Display
    # %Y = year, %m = month, %d = date,
    # %H = hour, %M = minute, %S = second, %T = HH:MM:SS,
    # %v = event, %q = frame number, %t = thread (camera) number,
    # %D = changed pixels, %N = noise level, \n = new line,
    # %i and %J = width and height of motion area,
    # %K and %L = X and Y coordinates of motion center
    # %C = value defined by text_event - do not use with text_event!
    # You can put quotation marks around the text to allow
    # leading spaces
    ############################################################

    # Locate and draw a box around the moving object.
    # Valid values: on, off, preview (default: off)
    # Set to 'preview' will only draw a box in preview_shot pictures.
    locate_motion_mode off

    # Set the look and style of the locate box if enabled.
    # Valid values: box, redbox, cross, redcross (default: box)
    # Set to 'box' will draw the traditional box.
    # Set to 'redbox' will draw a red box.
    # Set to 'cross' will draw a little cross to mark center.
    # Set to 'redcross' will draw a little red cross to mark center.
    locate_motion_style box

    # Draws the timestamp using same options as C function strftime(3)
    # Default: %Y-%m-%d\n%T = date in ISO format and time in 24 hour clock
    # Text is placed in lower right corner
    text_right %d.%m.%Y\n%T

    # Draw a user defined text on the images using same options as C function strftime(3)
    # Default: Not defined = no text
    # Text is placed in lower left corner
    ; text_left CAMERA %t
    text_left HofCam

    # Draw the number of changed pixed on the images (default: off)
    # Will normally be set to off except when you setup and adjust the motion settings
    # Text is placed in upper right corner
    text_changes off

    # This option defines the value of the special event conversion specifier %C
    # You can use any conversion specifier in this option except %C. Date and time
    # values are from the timestamp of the first image in the current event.
    # Default: %Y%m%d%H%M%S
    # The idea is that %C can be used filenames and text_left/right for creating
    # a unique identifier for each event.
    text_event %Y%m%d%H%M%S

    # Draw characters at twice normal size on images. (default: off)
    text_double on


    # Text to include in a JPEG EXIF comment
    # May be any text, including conversion specifiers.
    # The EXIF timestamp is included independent of this text.
    ;exif_text %i%J/%K%L

    ############################################################
    # Target Directories and filenames For Images And Films
    # For the options snapshot_, picture_, movie_ and timelapse_filename
    # you can use conversion specifiers
    # %Y = year, %m = month, %d = date,
    # %H = hour, %M = minute, %S = second,
    # %v = event, %q = frame number, %t = thread (camera) number,
    # %D = changed pixels, %N = noise level,
    # %i and %J = width and height of motion area,
    # %K and %L = X and Y coordinates of motion center
    # %C = value defined by text_event
    # Quotation marks round string are allowed.
    ############################################################

    # Target base directory for pictures and films
    # Recommended to use absolute path. (Default: current working directory)
    target_dir /home/pi

    # File path for snapshots (jpeg or ppm) relative to target_dir
    # Default: %v-%Y%m%d%H%M%S-snapshot
    # Default value is equivalent to legacy oldlayout option
    # For Motion 3.0 compatible mode choose: %Y/%m/%d/%H/%M/%S-snapshot
    # File extension .jpg or .ppm is automatically added so do not include this.
    # Note: A symbolic link called lastsnap.jpg created in the target_dir will always
    # point to the latest snapshot, unless snapshot_filename is exactly 'lastsnap'
    snapshot_filename %v-%Y%m%d%H%M%S-snapshot

    # File path for motion triggered images (jpeg or ppm) relative to target_dir
    # Default: %v-%Y%m%d%H%M%S-%q
    # Default value is equivalent to legacy oldlayout option
    # For Motion 3.0 compatible mode choose: %Y/%m/%d/%H/%M/%S-%q
    # File extension .jpg or .ppm is automatically added so do not include this
    # Set to 'preview' together with best-preview feature enables special naming
    # convention for preview shots. See motion guide for details
    picture_filename %v-%Y%m%d%H%M%S-%q

    # File path for motion triggered ffmpeg films (movies) relative to target_dir
    # Default: %v-%Y%m%d%H%M%S
    # Default value is equivalent to legacy oldlayout option
    # For Motion 3.0 compatible mode choose: %Y/%m/%d/%H%M%S
    # File extension .mpg or .avi is automatically added so do not include this
    # This option was previously called ffmpeg_filename
    movie_filename %v-%Y%m%d%H%M%S

    # File path for timelapse movies relative to target_dir
    # Default: %Y%m%d-timelapse
    # Default value is near equivalent to legacy oldlayout option
    # For Motion 3.0 compatible mode choose: %Y/%m/%d-timelapse
    # File extension .mpg is automatically added so do not include this
    timelapse_filename %Y%m%d-timelapse

    ############################################################
    # Global Network Options
    ############################################################
    # Enable or disable IPV6 for http control and stream (default: off )
    ipv6_enabled off

    ############################################################
    # Live Stream Server
    ############################################################

    # The mini-http server listens to this port for requests (default: 0 = disabled)
    stream_port 8080

    # Quality of the jpeg (in percent) images produced (default: 50)
    stream_quality 50

    # Output frames at 1 fps when no motion is detected and increase to the
    # rate given by stream_maxrate when motion is detected (default: off)
    stream_motion on

    # Maximum framerate for stream streams (default: 1)
    stream_maxrate 4

    # Restrict stream connections to localhost only (default: on)
    stream_localhost off

    # Limits the number of images per connection (default: 0 = unlimited)
    # Number can be defined by multiplying actual stream rate by desired number of seconds
    # Actual stream rate is the smallest of the numbers framerate and stream_maxrate
    stream_limit 0

    # Set the authentication method (default: 0)
    # 0 = disabled
    # 1 = Basic authentication
    # 2 = MD5 digest (the safer authentication)
    stream_auth_method 0

    # Authentication for the stream. Syntax username:password
    # Default: not defined (Disabled)
    ; stream_authentication username:password


    ############################################################
    # HTTP Based Control
    ############################################################

    # TCP/IP port for the http server to listen on (default: 0 = disabled)
    webcontrol_port 8081

    # Restrict control connections to localhost only (default: on)
    webcontrol_localhost off

    # Output for http server, select off to choose raw text plain (default: on)
    webcontrol_html_output on

    # Authentication for the http based control. Syntax username:password
    # Default: not defined (Disabled)
    ; webcontrol_authentication username:password


    ############################################################
    # Tracking (Pan/Tilt)
    #############################################################

    # Type of tracker (0=none (default), 1=stepper, 2=iomojo, 3=pwc, 4=generic, 5=uvcvideo, 6=servo)
    # The generic type enables the definition of motion center and motion size to
    # be used with the conversion specifiers for options like on_motion_detected
    track_type 0

    # Enable auto tracking (default: off)
    track_auto off

    # Serial port of motor (default: none)
    ;track_port /dev/ttyS0

    # Motor number for x-axis (default: 0)
    ;track_motorx 0

    # Set motorx reverse (default: 0)
    ;track_motorx_reverse 0

    # Motor number for y-axis (default: 0)
    ;track_motory 1

    # Set motory reverse (default: 0)
    ;track_motory_reverse 0

    # Maximum value on x-axis (default: 0)
    ;track_maxx 200

    # Minimum value on x-axis (default: 0)
    ;track_minx 50

    # Maximum value on y-axis (default: 0)
    ;track_maxy 200

    # Minimum value on y-axis (default: 0)
    ;track_miny 50

    # Center value on x-axis (default: 0)
    ;track_homex 128

    # Center value on y-axis (default: 0)
    ;track_homey 128

    # ID of an iomojo camera if used (default: 0)
    track_iomojo_id 0

    # Angle in degrees the camera moves per step on the X-axis
    # with auto-track (default: 10)
    # Currently only used with pwc type cameras
    track_step_angle_x 10

    [...]
  • trying to make OpenCV 3.2.0 work with virtualenv

    24 juillet 2017, par lollercoaster

    I’m on Ubuntu 16.04 with Python 2.7 and virtualenv & virtualenvwrapper.

    By following this guide I managed to get the following script working with my system Python2.7 which has cv2 globally installed.

    I used this script to install it :

    ######################################
    # INSTALL OPENCV ON UBUNTU OR DEBIAN #
    ######################################

    # |         THIS SCRIPT IS TESTED CORRECTLY ON         |
    # |----------------------------------------------------|
    # | OS             | OpenCV       | Test | Last test   |
    # |----------------|--------------|------|-------------|
    # | Ubuntu 16.04.2 | OpenCV 3.2.0 | OK   | 20 May 2017 |
    # | Debian 8.8     | OpenCV 3.2.0 | OK   | 20 May 2017 |
    # | Debian 9.0     | OpenCV 3.2.0 | OK   | 25 Jun 2017 |

    # 1. KEEP UBUNTU OR DEBIAN UP TO DATE

    sudo apt-get -y update
    sudo apt-get -y upgrade
    sudo apt-get -y dist-upgrade
    sudo apt-get -y autoremove


    # 2. INSTALL THE DEPENDENCIES

    # Build tools:
    sudo apt-get install -y build-essential cmake

    # GUI (if you want to use GTK instead of Qt, replace 'qt5-default' with 'libgtkglext1-dev' and remove '-DWITH_QT=ON' option in CMake):
    sudo apt-get install -y qt5-default libvtk6-dev

    # Media I/O:
    sudo apt-get install -y zlib1g-dev libjpeg-dev libwebp-dev libpng-dev libtiff5-dev libjasper-dev libopenexr-dev libgdal-dev

    # Video I/O:
    sudo apt-get install -y libdc1394-22-dev libavcodec-dev libavformat-dev libswscale-dev libtheora-dev libvorbis-dev libxvidcore-dev libx264-dev yasm libopencore-amrnb-dev libopencore-amrwb-dev libv4l-dev libxine2-dev

    # Parallelism and linear algebra libraries:
    sudo apt-get install -y libtbb-dev libeigen3-dev

    # Python:
    sudo apt-get install -y python-dev python-tk python-numpy python3-dev python3-tk python3-numpy

    # Documentation:
    sudo apt-get install -y doxygen

    # UI stuff
    sudo apt-get install libgtk-3-dev libatlas-base-dev gfortran


    # 3. INSTALL THE LIBRARY (YOU CAN CHANGE '3.2.0' FOR THE LAST STABLE VERSION)
    sudo apt-get install -y unzip wget

    # opencv contrib
    wget https://github.com/opencv/opencv_contrib/archive/3.2.0.zip -O opencv_contrib-3.2.0.zip
    unzip opencv_contrib-3.2.0.zip
    rm opencv_contrib-3.2.0.zip

    # opencv
    wget https://github.com/opencv/opencv/archive/3.2.0.zip
    unzip 3.2.0.zip
    rm 3.2.0.zip
    mv opencv-3.2.0 OpenCV-3.2.0
    cd OpenCV-3.2.0

    mkdir build
    cd build
    cmake -D WITH_QT=ON \
       -D WITH_OPENGL=ON \
       -D FORCE_VTK=ON \
       -D WITH_TBB=ON \
       -D WITH_GDAL=ON \
       -D WITH_XINE=ON \
       -D BUILD_EXAMPLES=ON \
       -D INSTALL_PYTHON_EXAMPLES=ON \
       -D ENABLE_PRECOMPILED_HEADERS=OFF \
       -D BUILD_NEW_PYTHON_SUPPORT=ON \
       ..

    make -j4
    sudo make install
    sudo ldconfig


    # 4. EXECUTE SOME OPENCV EXAMPLES AND COMPILE A DEMONSTRATION

    # To complete this step, please visit 'http://milq.github.io/install-opencv-ubuntu-debian'.

    The following script below works great with that system-wide installation :

    import cv2

    img = cv2.imread('some_img.jpg')

    Though this one doesn’t - even the system Python can’t read videos for some reason...

    import cv2

    video_capture = cv2.VideoCapture(0)
    ret, frame = video_capture.read()
    print ret  # always False

    but I want it to work with my virtualenv. So I recompiled OpenCV with :

    cmake -D WITH_QT=ON \
       -D WITH_OPENGL=ON \
       -D FORCE_VTK=ON \
       -D WITH_TBB=ON \
       -D WITH_GDAL=ON \
       -D WITH_XINE=ON \
       -D BUILD_EXAMPLES=ON \
       -D INSTALL_PYTHON_EXAMPLES=ON \
       -D ENABLE_PRECOMPILED_HEADERS=OFF \
       -D BUILD_NEW_PYTHON_SUPPORT=ON \
       -D OPENCV_EXTRA_MODULES_PATH=/home/me/code/myproject/opencv_contrib-3.2.0/modules \
       -D PYTHON_EXECUTABLE=~/.envs/myenv/bin/python \
       ..

    make -j4
    sudo make install
    sudo ldconfig

    Here’s the CMake log :

    -- Found VTK ver. 6.2.0 (usefile: /usr/lib/cmake/vtk-6.2/UseVTK.cmake)
    -- Caffe:   NO
    -- Protobuf:   YES
    -- Glog:   NO
    -- freetype2:   YES
    -- harfbuzz:    YES
    -- Module opencv_sfm disabled because the following dependencies are not found: Glog/Gflags
    -- freetype2:   YES
    -- harfbuzz:    YES
    -- Checking for modules 'tesseract;lept'
    --   No package 'tesseract' found
    --   No package 'lept' found
    -- Tesseract:   NO
    -- Check contents of vgg_generated_48.i ...
    -- Check contents of vgg_generated_64.i ...
    -- Check contents of vgg_generated_80.i ...
    -- Check contents of vgg_generated_120.i ...
    -- Check contents of boostdesc_bgm.i ...
    -- Check contents of boostdesc_bgm_bi.i ...
    -- Check contents of boostdesc_bgm_hd.i ...
    -- Check contents of boostdesc_binboost_064.i ...
    -- Check contents of boostdesc_binboost_128.i ...
    -- Check contents of boostdesc_binboost_256.i ...
    -- Check contents of boostdesc_lbgm.i ...
    --
    -- General configuration for OpenCV 3.2.0 =====================================
    --   Version control:               817bd7b-dirty
    --
    --   Extra modules:
    --     Location (extra):            /home/me/code/myproject/opencv_contrib-3.2.0/modules
    --     Version control (extra):     817bd7b-dirty
    --
    --   Platform:
    --     Timestamp:                   2017-07-20T18:25:26Z
    --     Host:                        Linux 4.8.0-58-generic x86_64
    --     CMake:                       3.5.1
    --     CMake generator:             Unix Makefiles
    --     CMake build tool:            /usr/bin/make
    --     Configuration:               Release
    --
    --   C/C++:
    --     Built as dynamic libs?:      YES
    --     C++ Compiler:                /usr/bin/c++  (ver 5.4.0)
    --     C++ flags (Release):         -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-comment -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -msse -msse2 -mno-avx -msse3 -mno-ssse3 -mno-sse4.1 -mno-sse4.2 -ffunction-sections -fvisibility=hidden -fvisibility-inlines-hidden -O3 -DNDEBUG  -DNDEBUG
    --     C++ flags (Debug):           -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-comment -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -msse -msse2 -mno-avx -msse3 -mno-ssse3 -mno-sse4.1 -mno-sse4.2 -ffunction-sections -fvisibility=hidden -fvisibility-inlines-hidden -g  -O0 -DDEBUG -D_DEBUG
    --     C Compiler:                  /usr/bin/cc
    --     C flags (Release):           -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wno-narrowing -Wno-comment -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -msse -msse2 -mno-avx -msse3 -mno-ssse3 -mno-sse4.1 -mno-sse4.2 -ffunction-sections -fvisibility=hidden -O3 -DNDEBUG  -DNDEBUG
    --     C flags (Debug):             -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wno-narrowing -Wno-comment -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -msse -msse2 -mno-avx -msse3 -mno-ssse3 -mno-sse4.1 -mno-sse4.2 -ffunction-sections -fvisibility=hidden -g  -O0 -DDEBUG -D_DEBUG
    --     Linker flags (Release):
    --     Linker flags (Debug):
    --     ccache:                      NO
    --     Precompiled headers:         NO
    --     Extra dependencies:          Qt5::Test Qt5::Concurrent Qt5::OpenGL /usr/lib/x86_64-linux-gnu/libwebp.so /usr/lib/x86_64-linux-gnu/libjasper.so /usr/lib/x86_64-linux-gnu/libImath.so /usr/lib/x86_64-linux-gnu/libIlmImf.so /usr/lib/x86_64-linux-gnu/libIex.so /usr/lib/x86_64-linux-gnu/libHalf.so /usr/lib/x86_64-linux-gnu/libIlmThread.so /usr/lib/libgdal.so dc1394 xine avcodec-ffmpeg avformat-ffmpeg avutil-ffmpeg swscale-ffmpeg Qt5::Core Qt5::Gui Qt5::Widgets /usr/lib/x86_64-linux-gnu/hdf5/serial/lib/libhdf5.so /usr/lib/x86_64-linux-gnu/libpthread.so /usr/lib/x86_64-linux-gnu/libsz.so /usr/lib/x86_64-linux-gnu/libdl.so /usr/lib/x86_64-linux-gnu/libm.so vtkRenderingOpenGL vtkImagingHybrid vtkIOImage vtkCommonDataModel vtkCommonMath vtkCommonCore vtksys vtkCommonMisc vtkCommonSystem vtkCommonTransforms vtkCommonExecutionModel vtkDICOMParser vtkIOCore /usr/lib/x86_64-linux-gnu/libz.so vtkmetaio /usr/lib/x86_64-linux-gnu/libjpeg.so /usr/lib/x86_64-linux-gnu/libpng.so /usr/lib/x86_64-linux-gnu/libtiff.so vtkImagingCore vtkRenderingCore vtkCommonColor vtkFiltersExtraction vtkFiltersCore vtkFiltersGeneral vtkCommonComputationalGeometry vtkFiltersStatistics vtkImagingFourier vtkalglib vtkFiltersGeometry vtkFiltersSources vtkInteractionStyle vtkRenderingLOD vtkFiltersModeling vtkIOPLY vtkIOGeometry /usr/lib/x86_64-linux-gnu/libjsoncpp.so vtkFiltersTexture vtkRenderingFreeType /usr/lib/x86_64-linux-gnu/libfreetype.so vtkftgl vtkIOExport vtkRenderingAnnotation vtkImagingColor vtkRenderingContext2D vtkRenderingGL2PS vtkRenderingContextOpenGL /usr/lib/libgl2ps.so vtkRenderingLabel dl m pthread rt /usr/lib/x86_64-linux-gnu/libGLU.so /usr/lib/x86_64-linux-gnu/libGL.so tbb
    --     3rdparty dependencies:       libprotobuf
    --
    --   OpenCV modules:
    --     To be built:                 core flann hdf imgproc ml photo reg surface_matching video viz dnn freetype fuzzy imgcodecs shape videoio highgui objdetect plot superres ts xobjdetect xphoto bgsegm bioinspired dpm face features2d line_descriptor saliency text calib3d ccalib cvv datasets rgbd stereo tracking videostab xfeatures2d ximgproc aruco optflow phase_unwrapping stitching structured_light java python2 python3
    --     Disabled:                    world contrib_world
    --     Disabled by dependency:      -
    --     Unavailable:                 cudaarithm cudabgsegm cudacodec cudafeatures2d cudafilters cudaimgproc cudalegacy cudaobjdetect cudaoptflow cudastereo cudawarping cudev cnn_3dobj matlab sfm
    --
    --   GUI:
    --     QT 5.x:                      YES (ver 5.5.1)
    --     QT OpenGL support:           YES (Qt5::OpenGL 5.5.1)
    --     OpenGL support:              YES (/usr/lib/x86_64-linux-gnu/libGLU.so /usr/lib/x86_64-linux-gnu/libGL.so)
    --     VTK support:                 YES (ver 6.2.0)
    --
    --   Media I/O:
    --     ZLib:                        /usr/lib/x86_64-linux-gnu/libz.so (ver 1.2.8)
    --     JPEG:                        /usr/lib/x86_64-linux-gnu/libjpeg.so (ver )
    --     WEBP:                        /usr/lib/x86_64-linux-gnu/libwebp.so (ver encoder: 0x0202)
    --     PNG:                         /usr/lib/x86_64-linux-gnu/libpng.so (ver 1.2.54)
    --     TIFF:                        /usr/lib/x86_64-linux-gnu/libtiff.so (ver 42 - 4.0.6)
    --     JPEG 2000:                   /usr/lib/x86_64-linux-gnu/libjasper.so (ver 1.900.1)
    --     OpenEXR:                     /usr/lib/x86_64-linux-gnu/libImath.so /usr/lib/x86_64-linux-gnu/libIlmImf.so /usr/lib/x86_64-linux-gnu/libIex.so /usr/lib/x86_64-linux-gnu/libHalf.so /usr/lib/x86_64-linux-gnu/libIlmThread.so (ver 2.2.0)
    --     GDAL:                        /usr/lib/libgdal.so
    --     GDCM:                        NO
    --
    --   Video I/O:
    --     DC1394 1.x:                  NO
    --     DC1394 2.x:                  YES (ver 2.2.4)
    --     FFMPEG:                      YES
    --       avcodec:                   YES (ver 56.60.100)
    --       avformat:                  YES (ver 56.40.101)
    --       avutil:                    YES (ver 54.31.100)
    --       swscale:                   YES (ver 3.1.101)
    --       avresample:                NO
    --     GStreamer:                   NO
    --     OpenNI:                      NO
    --     OpenNI PrimeSensor Modules:  NO
    --     OpenNI2:                     NO
    --     PvAPI:                       NO
    --     GigEVisionSDK:               NO
    --     Aravis SDK:                  NO
    --     UniCap:                      NO
    --     UniCap ucil:                 NO
    --     V4L/V4L2:                    NO/YES
    --     XIMEA:                       NO
    --     Xine:                        YES (ver 1.2.6)
    --     gPhoto2:                     NO
    --
    --   Parallel framework:            TBB (ver 4.4 interface 9002)
    --
    --   Other third-party libraries:
    --     Use IPP:                     9.0.1 [9.0.1]
    --          at:                     /home/me/code/myproject/OpenCV-3.2.0/build/3rdparty/ippicv/ippicv_lnx
    --     Use IPP Async:               NO
    --     Use VA:                      NO
    --     Use Intel VA-API/OpenCL:     NO
    --     Use Lapack:                  NO
    --     Use Eigen:                   YES (ver 3.2.92)
    --     Use Cuda:                    NO
    --     Use OpenCL:                  YES
    --     Use OpenVX:                  NO
    --     Use custom HAL:              NO
    --
    --   OpenCL:                        <dynamic loading="loading" of="of" opencl="opencl" library="library">
    --     Include path:                /home/me/code/myproject/OpenCV-3.2.0/3rdparty/include/opencl/1.2
    --     Use AMDFFT:                  NO
    --     Use AMDBLAS:                 NO
    --
    --   Python 2:
    --     Interpreter:                 /home/me/.envs/myenv/bin/python (ver 2.7.12)
    --     Libraries:                   /usr/lib/x86_64-linux-gnu/libpython2.7.so (ver 2.7.12)
    --     numpy:                       /home/me/.envs/myenv/local/lib/python2.7/site-packages/numpy/core/include (ver 1.13.1)
    --     packages path:               lib/python2.7/site-packages
    --
    --   Python 3:
    --     Interpreter:                 /usr/bin/python3 (ver 3.5.2)
    --     Libraries:                   /usr/lib/x86_64-linux-gnu/libpython3.5m.so (ver 3.5.2)
    --     numpy:                       /usr/lib/python3/dist-packages/numpy/core/include (ver 1.11.0)
    --     packages path:               lib/python3.5/dist-packages
    --
    --   Python (for build):            /home/me/.envs/myenv/bin/python
    --
    --   Java:
    --     ant:                         /usr/bin/ant (ver 1.9.6)
    --     JNI:                         /usr/lib/jvm/default-java/include /usr/lib/jvm/default-java/include/linux /usr/lib/jvm/default-java/include
    --     Java wrappers:               YES
    --     Java tests:                  YES
    --
    --   Matlab:                        Matlab not found or implicitly disabled
    --
    --   Documentation:
    --     Doxygen:                     /usr/bin/doxygen (ver 1.8.11)
    --
    --   Tests and samples:
    --     Tests:                       YES
    --     Performance tests:           YES
    --     C/C++ Examples:              YES
    --
    --   Install path:                  /usr/local
    --
    --   cvconfig.h is in:              /home/me/code/myproject/OpenCV-3.2.0/build
    -- -----------------------------------------------------------------
    --
    </dynamic>

    Unfortunately, while this works and I can import cv2 in the shell, it cannot read video using the above script, probably due to incorrect compilation or linking of ffmpeg ? The confusing part is the system-wide installation of OpenCV works fine, even without ffmpeg installed !

    What am I doing wrong ? How can I get OpenCV working with a virtualenv ?

    ====

    EDIT : Running the C++ video writing example has this result :

    $ cd /home/me/code/myproject/OpenCV-3.2.0/build/bin
    $ ./cpp-tutorial-video-write ../../samples/data/vtest.avi R Y
    ------------------------------------------------------------------------------
    This program shows how to write video files.
    You can extract the R or G or B color channel of the input video.
    Usage:
    ./video-write  [ R | G | B] [Y | N]
    ------------------------------------------------------------------------------

    OpenCV: FFMPEG: tag 0xffffffff/'����' is not found (format 'avi / AVI (Audio Video Interleaved)')'

    (cpp-tutorial-video-write:19523): GStreamer-CRITICAL **: gst_element_make_from_uri: assertion 'gst_uri_is_valid (uri)' failed
    OpenCV Error: Unsupported format or combination of formats (Gstreamer Opencv backend does not support this codec.) in CvVideoWriter_GStreamer::open, file /home/me/code/myproject/OpenCV-3.2.0/modules/videoio/src/cap_gstreamer.cpp, line 1388
    VIDEOIO(cvCreateVideoWriter_GStreamer(filename, fourcc, fps, frameSize, is_color)): raised OpenCV exception:

    /home/me/code/myproject/OpenCV-3.2.0/modules/videoio/src/cap_gstreamer.cpp:1388: error: (-210) Gstreamer Opencv backend does not support this codec. in function CvVideoWriter_GStreamer::open

    Could not open the output video for write: ../../samples/data/vtest.avi

    And the opencv_test_videoio unit test reports the following : https://pastebin.com/q4mf224Q

    However, running the c++ video starter example DOES work, with the following command and output, I can see the webcam working and streaming video in the highgui interface :

    $ ./cpp-example-videocapture_starter 0
    VIDEOIO ERROR: V4L: device 0: Unable to query number of channels
    (ERROR)icvOpenAVI_XINE(): Unable to initialize video driver.
    GStreamer: Error opening bin: no element "0"
    press space to save a picture. q or esc to quit
    init done
    opengl support available