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• Is there any library in python or can we use FFMPEG to detect the appearance of the lines pattern in video that is shown in the image attached below ? [closed]

  21 septembre 2022, par Shreyas R

  Video defect appearing frame

  


  Hi All,

  


  I am trying to find a way to detect the appearance of this lines pattern embedded in the link below.
If I get any match of this pattern in a video, I need to record that particular timestamp of the video where I got the pattern match.

  


  My idea is to take the image and compare it against the video to find for approximate match percentage. If I get it, then I record that particular timestamp within a .txt file.

  


  Is there any better way to achieve this ?
I think we can use Python or FFMPEG video filters to get a solution for this.

  


  It would really help if anyone can support with a solution. Thanks

  


  Update :
I got a reference where they have proposed a solution similar to my concern.

  


  https://aws.amazon.com/blogs/media/metfc-automatically-compare-two-videos-to-find-common-content/

  


  So we can try to achieve some output from this solution.

  


• Windows - Capturing all desktop screens and sessions

  5 février 2018, par Jack

  I’m trying to capture screen video to emulate similar functionality as TeamViewer and mstsc (while supporting multiple logins), which is currently being done wonderfully using ffmpeg with "-f gdbgrab" option.

  However, whenever I switch user, including trying to elevate to administrator, not only I cannot capture the UAC or logon screens, but the process terminates completely :

  [gdigrab @ 07e34780] Failed to capture image (error 5)
  
  desktop: I/O error

  (the same happens when running as Administrator and even SYSTEM)

  From what I understand, this is due to Windows having different sessions for the logon screen, UAC screen, etc. and from what I’ve read here :
  Session 0 capture screen
   it seems you cannot capture video from other sessions, nor connect to multiple sessions, hence mstsc is not being used either.

  TeamViewer is able to capture UAC and even logon screen. How so ?

  (optimally, I would used mstsc however it logs-off already logged users)

  This is what I currently use to stream :

  ffmpeg -f gdigrab -framerate 10 -i desktop -rtmp_live live -c:v mpeg4 -f rtsp -rtsp_transport udp rtsp://localhost:8888/live.sdp?udp

  (I already have a more-or-less functional solution for HID input but may also not work properly with UAC, etc.)

• ffmpeg custom buffer sink filter

  25 novembre 2018, par NadavRub

  Environment

  • Ubuntu 18.04
  • C++
  • ffmpeg 3.4 (git master)
  • ffmpeg is used as a shared lib (InProc) via the C++ API

  Use-case

  • Per this link I am trying to use the ’avfilter_graph_*’ APIs to create ffmpeg graph
  • I would like the graph output to be sent out to my custom code ( part of the hosting application )

  Considered implementations

  • [A] Implement a custom sink filter ( part of libavfilter ) to implement my custom logic
  • [B] Implement a custom sink filter to grab the output samples and send them out to my application ( something similar to DShow SampleGrabber )

  Problem at hand

  With either of the above mentioned approaches the ffmpeg code has to be modified, and this impose an overhead in supporting future ffmpeg releases

  I wonder if there is any straight forward approach for an external ( hosting ) application to grab the graph output w/ minimal copying of the payload.

  Is there any way to use a custom AVIOContext to achieve that ? can I construct a graph connected to an output AVIOContext ? can I create a custom filter implemented in a module external to libavfilter and associate it w/ the graph using ’AVFilterContext’ ?