Results 1 to 4 of 4

Thread: Reading a video stream, grabbing images from it

  1. #1
    Join Date
    Jan 2009
    Location
    Germany
    Posts
    387
    Thanks
    101
    Thanked 15 Times in 15 Posts
    Qt products
    Qt4 Qt5
    Platforms
    Unix/X11 Windows

    Default Reading a video stream, grabbing images from it

    Hello!

    I need to read and process a video stream coming from a camera, which is connected to a strange and old linux machine (server), which I can only access remotely. Display and processing of the video stream should happen on Linux and Windows clients that access the video stream over network. So far I am following the strategy to use gstreamer to encode and send out the video stream on the server. On the clients I would like to use Qt to receive the stream and to grab single images (QImage objects) from it, and to embed all this into a gui application, but I have no clue how this part would work out. Can anyone give me a few pointers please? I am looking into the QMediaPlayer object, but since I have never had anything to do with video so far, this is all very new und unfamiliar to me.

    Thanks
    Cruz

  2. #2
    Join Date
    Jan 2006
    Location
    Graz, Austria
    Posts
    8,416
    Thanks
    37
    Thanked 1,544 Times in 1,494 Posts
    Qt products
    Qt3 Qt4 Qt5
    Platforms
    Unix/X11 Windows

    Default Re: Reading a video stream, grabbing images from it

    Hmm. Since you are using GStreamer on the source side you could check if you could use Qt GStreamer binding on the client side to decode and display the stream.

    One other option would be to see if there is a common streaming backend implementation for QtMultimedia on both target platforms and ensure the server sends its stream using that protocol.

    Cheers,
    _

  3. #3
    Join Date
    Jan 2009
    Location
    Germany
    Posts
    387
    Thanks
    101
    Thanked 15 Times in 15 Posts
    Qt products
    Qt4 Qt5
    Platforms
    Unix/X11 Windows

    Default Re: Reading a video stream, grabbing images from it

    I was hoping to avoid installing gstreamer (or qtgstreamer) on the client side altogether, as this would be some hassle to support all sorts of operating systems. I was hoping to find a solution along the lines of streaming the video out with gstreamer from the server with some standard encoding scheme, and then opening the stream on the client side with some Qt multimedia object. The only object I found that can open a resource URL is QMediaContent, even though I have no idea how I would be able to set the format, or encoding. Will I be able to accomplish opening the video stream this way?

  4. #4
    Join Date
    Jan 2006
    Location
    Graz, Austria
    Posts
    8,416
    Thanks
    37
    Thanked 1,544 Times in 1,494 Posts
    Qt products
    Qt3 Qt4 Qt5
    Platforms
    Unix/X11 Windows

    Default Re: Reading a video stream, grabbing images from it

    Quote Originally Posted by Cruz View Post
    I was hoping to avoid installing gstreamer (or qtgstreamer) on the client side altogether, as this would be some hassle to support all sorts of operating systems.
    Right, but it also provides common ground.

    The other option might end up to have to implement a new QtMultimedia source with the respective platform's backend technology.

    Quote Originally Posted by Cruz View Post
    I was hoping to find a solution along the lines of streaming the video out with gstreamer from the server with some standard encoding scheme, and then opening the stream on the client side with some Qt multimedia object.
    Right, that's why my other suggestion was to research if QtMultimedia has some standard protocol streaming source implementation, e.g. WebRTC or RTSP, available on both your target platforms.

    Another option might be to check if the QWebEngine implementation supports WebRTC and let the server send that.

    Cheers,
    _

Similar Threads

  1. Replies: 1
    Last Post: 3rd August 2012, 17:39
  2. Video Stream Over UDP
    By bajoelkid12 in forum Qt Programming
    Replies: 4
    Last Post: 1st June 2011, 08:02
  3. Saving video stream
    By frknml in forum Qt Programming
    Replies: 0
    Last Post: 13th December 2010, 08:10
  4. How can we convert video stream to QPixmap?
    By learning_qt in forum Qt Programming
    Replies: 1
    Last Post: 9th September 2008, 23:44
  5. Video Stream, extending QIODevice
    By rextr in forum Qt Programming
    Replies: 3
    Last Post: 27th June 2008, 08:55

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Digia, Qt and their respective logos are trademarks of Digia Plc in Finland and/or other countries worldwide.