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• UVC webcam with ffplay outputs only noise ?

  1er mars 2024, par Abdulla Masud

  (My end goal is to use a UVC webcam with esp32 or raspberry pi. I was hoping to learn while doing some fun projects.)

  


  I have an old UVC webcam (Creative model ct6840) but I can't seem to get it to work with ffplay. I have tried looking through the documentation and other questions here but nothing is working for me. So far I have only been able to achieve a noisy-jittery output.

  


  Running ffplay -f rawvideo -video_size 670x480 /dev/video1, I get :

  


  

  


  Can someone help me understand how to make the camera work with ffplay ?

  


  The following is the information of my webcam :

  


  $ ffmpeg -f v4l2 -list_formats all -i /dev/video2

  


  [video4linux2,v4l2 @ 0x17eb3c0] Compressed: Unsupported :          GSPCA OV511 : 320x240 640x480


  


  $ v4l-info /dev/video2

  


  ### v4l2 device info [/dev/video2] ###
general info
    VIDIOC_QUERYCAP
    driver                  : "ov519"
    card                    : "USB Camera (05a9:0511)"
    bus_info                : "usb-0000:00:14.0-8.2"
    version                 : 6.1.79
    capabilities            : 0x85200001 [VIDEO_CAPTURE,?,READWRITE,STREAMING,(null)]

standards

inputs
    VIDIOC_ENUMINPUT(0)
    index                   : 0
    name                    : "ov519"
    type                    : CAMERA
    audioset                : 0
    tuner                   : 0
    std                     : 0x0 []
    status                  : 0x0 []

video capture
    VIDIOC_ENUM_FMT(0,VIDEO_CAPTURE)
    index                   : 0
    type                    : VIDEO_CAPTURE
    flags                   : 1
    description             : "GSPCA OV511"
    pixelformat             : 0x3131354f [O511]
    VIDIOC_G_FMT(VIDEO_CAPTURE)
    type                    : VIDEO_CAPTURE
    fmt.pix.width           : 640
    fmt.pix.height          : 480
    fmt.pix.pixelformat     : 0x3131354f [O511]
    fmt.pix.field           : NONE
    fmt.pix.bytesperline    : 640
    fmt.pix.sizeimage       : 614400
    fmt.pix.colorspace      : JPEG
    fmt.pix.priv            : 4276996862

controls
    VIDIOC_QUERYCTRL(BASE+0)
    id                      : 9963776
    type                    : INTEGER
    name                    : "Brightness"
    minimum                 : 0
    maximum                 : 255
    step                    : 1
    default_value           : 127
    flags                   : 48
    VIDIOC_QUERYCTRL(BASE+1)
    id                      : 9963777
    type                    : INTEGER
    name                    : "Contrast"
    minimum                 : 0
    maximum                 : 255
    step                    : 1
    default_value           : 127
    flags                   : 32
    VIDIOC_QUERYCTRL(BASE+2)
    id                      : 9963778
    type                    : INTEGER
    name                    : "Saturation"
    minimum                 : 0
    maximum                 : 255
    step                    : 1
    default_value           : 127
    flags                   : 32
    VIDIOC_QUERYCTRL(BASE+24)
    id                      : 9963800
    type                    : MENU
    name                    : "Power Line Frequency"
    minimum                 : 0
    maximum                 : 2
    step                    : 1
    default_value           : 0
    flags                   : 0
    VIDIOC_QUERYCTRL(BASE+32)
    id                      : 9963808
    type                    : BOOLEAN
    name                    : "Brightness, Automatic"
    minimum                 : 0
    maximum                 : 1
    step                    : 1
    default_value           : 1
    flags                   : 8


  


  Can someone guide me here please ? Any advice will be greatly appreciated 

  


  (P.S. the camera works perfectly with "guvcview" gtk application but since I want to use the camera with raspberry pi, I want it to work with ffplay...)

  


• It’s January 28th : Let’s celebrate Data Privacy !

  29 janvier 2018, par Matomo Core Team

  It is a special Sunday here for us at Matomo, as today is international Data Privacy Day. The day was created in 2007 to raise awareness of the importance of data privacy for people and businesses worldwide.

  

  What is data privacy about ?

  Personal data refers to any data which is collected and can be linked to an individual human being such as phone records, credit card transactions, GPS position, IP addresses, browsing history… So basically, personal data refers to your identity online. That is why you should be highly concerned about sending your personal data (or your customers’ personal data) away. It is important to be aware of who is collecting the information and how it is being used.

  What big changes are happening in 2018 ?

  New privacy regulations GDPR comes into play next May 2018 : GDPR will bring about some changes (in the right direction) by making people and businesses aware of what data privacy means, and what they should be doing to protect their customers’ privacy. With these new regulations, data privacy awareness is reaching a critical milestone this year.

  How can I protect my privacy ?

  Here are a few tips to protect your privacy :

  • Educate yourself on the importance of privacy : the more informed you are the better.
  • Use open source solutions where you can keep full control of your own data (such as NextCloud instead of Dropbox and of course Matomo instead of Google Analytics),
  • Experiment with different online services to protect your data privacy, for example using an alternative search engine (such as DuckDuckGo instead of Google) or an alternative email provider (such as ProtonMail).

  What’s coming next for Matomo and Privacy ?

  Here at Matomo, we are building the leading decentralised open web analytics platform. We’re currently working on new sets of privacy features to make compliance with GDPR a breeze. Stay tuned here to be notified when we launch the new privacy compliance tools !

  And in case you’ve missed this important info, you may be interested in :

  • Configure Privacy Settings in Matomo
  • 11 ways Matomo Analytics helps you to protect your visitors privacy

   

  The post It’s January 28th : Let’s celebrate Data Privacy ! appeared first on Analytics Platform - Matomo.

• Recover corrupt MTS file via ffmpeg

  24 juin 2017, par Ashley

  I have many large video files from an overseas trip. 90% of them are great, but there are a few I recorded on a dodgy SD card which are unable to play for some reason. They are all .MTS files.

  In VLC, an error appears when trying to play them :

  Unidentified codec:
  
  VLC could not identify the audio or video codec

  I don’t know much about video files or codecs, but I am savvy enough to use ffmpeg, which I thought might be my best bet.

  I attempted this on one of the files (call it ’input.MTS’) :

  ffmpeg -i input.MTS output.mp4

  The result was this :

  ffmpeg version N-82597-gd316b21 Copyright (c) 2000-2016 the FFmpeg developers
  
    built with gcc 5.4.0 (GCC)
  
    configuration: --enable-gpl --enable-version3 --disable-w32threads --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-libschroedinger --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-libzimg --enable-lzma --enable-decklink --enable-zlib
  
    libavutil      55. 40.100 / 55. 40.100
  
    libavcodec     57. 66.106 / 57. 66.106
  
    libavformat    57. 58.100 / 57. 58.100
  
    libavdevice    57.  2.100 / 57.  2.100
  
    libavfilter     6. 67.100 /  6. 67.100
  
    libswscale      4.  3.101 /  4.  3.101
  
    libswresample   2.  4.100 /  2.  4.100
  
    libpostproc    54.  2.100 / 54.  2.100
  
  [adp @ 0000000000026380] Format adp detected only with low score of 25, misdetection possible!
  
  Input #0, adp, from 'input.MTS':
  
    Duration: 00:05:38.69, start: 0.000000, bitrate: 438 kb/s
  
      Stream #0:0: Audio: adpcm_dtk, 48000 Hz, stereo, s16p
  
  Output #0, mp4, to 'output.mp4':
  
    Metadata:
  
      encoder         : Lavf57.58.100
  
      Stream #0:0: Audio: aac (LC) ([64][0][0][0] / 0x0040), 48000 Hz, stereo, fltp, 128 kb/s
  
      Metadata:
  
        encoder         : Lavc57.66.106 aac
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (adpcm_dtk (native) -> aac (native))
  
  Press [q] to stop, [?] for help
  
  size=     312kB time=00:05:38.68 bitrate=   7.6kbits/s speed=33.7x
  
  video:0kB audio:250kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 25.134468%
  
  [aac @ 00000000025c5ba0] Qavg: 65531.879

  The output.mp4 file now plays in VLC without error, and is 5 minutes and 38 seconds long. However, there is no audio or video.

  Also, input.MTS is 18 MB, and output.mp4 is 0.313 MB.

  What is the correct way to recover this video ?