Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. Mobile and Embedded
  4. Display Gstreamer video on Android
Forum Updated to NodeBB v4.3 + New Features

Display Gstreamer video on Android

Scheduled Pinned Locked Moved Unsolved Mobile and Embedded
gstreamergstreamer videoandroidopengl
36 Posts 4 Posters 21.8k Views 3 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • S SGaist
    3 May 2016, 20:18

    Do you mean build Qt's GStreamer backend for Android ?

    You have to check the availability of the module's dependencies for these platform (or build them by hand)

    D Offline
    D Offline
    don-prog
    wrote on 3 May 2016, 20:31 last edited by
    #9

    @SGaist ok, and can you share some simple example how can I build Qt's GStreamer backend for Android? Because I even don't know how I can start.

    1 Reply Last reply
    0
    • S Offline
      S Offline
      SGaist
      Lifetime Qt Champion
      wrote on 3 May 2016, 20:45 last edited by
      #10

      Sorry, I don't have an example by hand but based on the QtMultimedia sources, the first thing I'd do is get gstreamer for Android and then I'd modify the plugins.pro file and add the gstreamer subdir to the list in the android scope.

      Interested in AI ? www.idiap.ch
      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

      D 1 Reply Last reply 3 May 2016, 20:57
      0
      • S SGaist
        3 May 2016, 20:45

        Sorry, I don't have an example by hand but based on the QtMultimedia sources, the first thing I'd do is get gstreamer for Android and then I'd modify the plugins.pro file and add the gstreamer subdir to the list in the android scope.

        D Offline
        D Offline
        don-prog
        wrote on 3 May 2016, 20:57 last edited by
        #11

        @SGaist ok, thanks. And what is the difference between QtGstreamer module and Qt's GStreamer backend?

        1 Reply Last reply
        0
        • S Offline
          S Offline
          SGaist
          Lifetime Qt Champion
          wrote on 3 May 2016, 21:01 last edited by
          #12

          The QtGstreamer module is on a lower-level. It essentially provides you a nice Qt API to build your GStreamer pipelines and a set of video sync for QtWidgets and QtQuick.

          Interested in AI ? www.idiap.ch
          Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

          D 1 Reply Last reply 3 May 2016, 21:09
          0
          • S SGaist
            3 May 2016, 21:01

            The QtGstreamer module is on a lower-level. It essentially provides you a nice Qt API to build your GStreamer pipelines and a set of video sync for QtWidgets and QtQuick.

            D Offline
            D Offline
            don-prog
            wrote on 3 May 2016, 21:09 last edited by
            #13

            @SGaist as I understand QtGstreamer will works for my issue too, so what is more preferable? How can I use QtGstreamer? And is it cross-platform? Thanks!

            1 Reply Last reply
            0
            • S Offline
              S Offline
              SGaist
              Lifetime Qt Champion
              wrote on 3 May 2016, 21:16 last edited by
              #14

              It should run on the same platforms as Qt as long as you can satisfy its dependencies.

              I'd first try to build the backend. It will likely be less work.

              Interested in AI ? www.idiap.ch
              Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

              D 1 Reply Last reply 3 May 2016, 21:47
              0
              • S SGaist
                3 May 2016, 21:16

                It should run on the same platforms as Qt as long as you can satisfy its dependencies.

                I'd first try to build the backend. It will likely be less work.

                D Offline
                D Offline
                don-prog
                wrote on 3 May 2016, 21:47 last edited by
                #15

                @SGaist understood. Thanks for the explanations. About backend:
                I need download GStreamer for Android(this I already did, right?), create plugins.pro file in the my project(I don't know even what is it, but I will read) and add GStreamer dir to the list in the android scope(don't heard about this too). Is it all what I need?

                1 Reply Last reply
                0
                • S Offline
                  S Offline
                  SGaist
                  Lifetime Qt Champion
                  wrote on 3 May 2016, 22:05 last edited by
                  #16

                  No, you have to build the plugin from the sources and then install them

                  Interested in AI ? www.idiap.ch
                  Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                  D 1 Reply Last reply 3 May 2016, 22:14
                  0
                  • S SGaist
                    3 May 2016, 22:05

                    No, you have to build the plugin from the sources and then install them

                    D Offline
                    D Offline
                    don-prog
                    wrote on 3 May 2016, 22:14 last edited by
                    #17

                    @SGaist can you share the link which describes what I need to do? Or some additional reading? I'm sorry but I really don't understand a lot of things. Where I need to set a plugins.pro? What I need to set within it? About which plugin are you said? How and where I need to install it? How connect GStreamer to all these things?

                    1 Reply Last reply
                    0
                    • S Offline
                      S Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on 4 May 2016, 07:06 last edited by
                      #18

                      You don't need to create any file. You have to first get the sources of the QtMultimedia module.

                      There you'll find the plugins folder with the matching plugins.pro file

                      Interested in AI ? www.idiap.ch
                      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                      1 Reply Last reply
                      0
                      • L Offline
                        L Offline
                        LuJoRi
                        wrote on 4 May 2016, 07:45 last edited by LuJoRi 5 Apr 2016, 09:21
                        #19

                        Hi don-prog!

                        I've had the same issue as you...displaying a GStreamer video on Android within a Qt application!
                        It was a hard way to find out how to get it alltogether work and it took me a long time! I wasn't able to find really useful hints about this issue.

                        First I also tried it with QtGStreamer, but I didn't get it work for Android. After trying and trying and trying (...) I decided to look for another way to go. By the way - for Linux the QtGStreamer worked like a charm.

                        As you can see at this link (https://wiki.qt.io/Qt_5.5.0_Multimedia_Backends) the multimedia backend of Qt uses different multimedia frameworks on different platforms --> GStreamer is only used for Linux and I think this decision wasn't made causeless! I don't think it will be so easy to get the Qt's GStreamer-Backend to work for Android since a Qt application for Android comes with partial other characteristics than a Qt application for Linux. That's based in the differences between the dissimilar windowing-systems of Android and Desktop-Linux.

                        If you display some patience I'll show you how I did it?

                        Greetz, Lukas

                        1 Reply Last reply
                        0
                        • S Offline
                          S Offline
                          SGaist
                          Lifetime Qt Champion
                          wrote on 4 May 2016, 10:38 last edited by SGaist 5 Apr 2016, 10:38
                          #20

                          Hi and welcome to devnet,

                          @LuJoRi Indeed it wasn't mad causeless because Qt uses as much as possible native frameworks.

                          If I understand you correctly you successfully used GStreamer on Android with Qt to do video rendering ?

                          Interested in AI ? www.idiap.ch
                          Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                          D L 2 Replies Last reply 4 May 2016, 20:19
                          0
                          • S SGaist
                            4 May 2016, 10:38

                            Hi and welcome to devnet,

                            @LuJoRi Indeed it wasn't mad causeless because Qt uses as much as possible native frameworks.

                            If I understand you correctly you successfully used GStreamer on Android with Qt to do video rendering ?

                            D Offline
                            D Offline
                            don-prog
                            wrote on 4 May 2016, 20:19 last edited by
                            #21

                            @SGaist ok, I downloaded QtMultimedia source and found that block:

                            android {
                               SUBDIRS += android opensles
                            }
                            

                            What I should to do next? Just add /home/user/Downloads/gstreamer-1.0-android-armv7-1.8.0 in the end?

                            1 Reply Last reply
                            0
                            • S SGaist
                              4 May 2016, 10:38

                              Hi and welcome to devnet,

                              @LuJoRi Indeed it wasn't mad causeless because Qt uses as much as possible native frameworks.

                              If I understand you correctly you successfully used GStreamer on Android with Qt to do video rendering ?

                              L Offline
                              L Offline
                              LuJoRi
                              wrote on 4 May 2016, 20:51 last edited by LuJoRi 5 Apr 2016, 21:13
                              #22

                              @SGaist, yes exactly! It was one of my core topics of my master thesis which I'll finally release after the weekend :)
                              @don-prog, @SGaist, are you interested in my solution? It will take some time for me to explain you in english since it isn't my first language (it's german).

                              A few quick hints:

                              • you should look for a surface of the Java/Android-API and get the pointer on it via ANativeWindow_fromSurface(...) --> so you can handle the surface's display area within C++/Qt

                              • with this pointer you are able to use the standard GStreamer way to render a video in a specific display area.
                                Your function call was:
                                gst_video_overlay_set_window_handle(GST_VIDEO_OVERLAY(video_sink), this->ui->playback_widget->winId());
                                --> you have to use the pointer on the native window instead of winId()...the winId() function returns useful values on Linux but not on Android!

                              D 1 Reply Last reply 4 May 2016, 21:25
                              0
                              • S Offline
                                S Offline
                                SGaist
                                Lifetime Qt Champion
                                wrote on 4 May 2016, 20:55 last edited by
                                #23

                                @don-prog Sure thing !

                                That may avoid @don-prog some pain.

                                @don-prog you would need to add gstreamer to SUBDIRS. It's the name of the plugin dir. However, AFAIK, that plugin uses pkg-config to find gstreamer's library/includes so it may be problematic. You would have to put the the paths yourself in there.

                                Interested in AI ? www.idiap.ch
                                Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                1 Reply Last reply
                                0
                                • L LuJoRi
                                  4 May 2016, 20:51

                                  @SGaist, yes exactly! It was one of my core topics of my master thesis which I'll finally release after the weekend :)
                                  @don-prog, @SGaist, are you interested in my solution? It will take some time for me to explain you in english since it isn't my first language (it's german).

                                  A few quick hints:

                                  • you should look for a surface of the Java/Android-API and get the pointer on it via ANativeWindow_fromSurface(...) --> so you can handle the surface's display area within C++/Qt

                                  • with this pointer you are able to use the standard GStreamer way to render a video in a specific display area.
                                    Your function call was:
                                    gst_video_overlay_set_window_handle(GST_VIDEO_OVERLAY(video_sink), this->ui->playback_widget->winId());
                                    --> you have to use the pointer on the native window instead of winId()...the winId() function returns useful values on Linux but not on Android!

                                  D Offline
                                  D Offline
                                  don-prog
                                  wrote on 4 May 2016, 21:25 last edited by
                                  #24

                                  @LuJoRi many thanks for your support and experience! I am very interested in your solution because I already thought about some way like yours, but I have some misunderstandings:
                                  How can I use ANativeWindow_fromSurface() from Qt and with which arguments?

                                  L 1 Reply Last reply 4 May 2016, 22:16
                                  0
                                  • D don-prog
                                    4 May 2016, 21:25

                                    @LuJoRi many thanks for your support and experience! I am very interested in your solution because I already thought about some way like yours, but I have some misunderstandings:
                                    How can I use ANativeWindow_fromSurface() from Qt and with which arguments?

                                    L Offline
                                    L Offline
                                    LuJoRi
                                    wrote on 4 May 2016, 22:16 last edited by LuJoRi 5 Apr 2016, 22:23
                                    #25

                                    @don-prog you have to do function calls from C++/Qt to Java/Android-API via JNI. Look for QAndroidJniObject (http://doc.qt.io/qt-5/qandroidjniobject.html) --> that's a way to create instances of classes of the Java/Android-API. Furthermore you can call their methods - for example via

                                     QAndroidJniObject::callObjectMethod(const char *methodName, const char *signature, ... ) 
                                    

                                    That means that you first have to manage a Java surface object will be created. You do this via JNI. Then you can put this one as an argument to the ANativeWindow_fromSurface function.

                                    D 1 Reply Last reply 4 May 2016, 22:35
                                    1
                                    • L LuJoRi
                                      4 May 2016, 22:16

                                      @don-prog you have to do function calls from C++/Qt to Java/Android-API via JNI. Look for QAndroidJniObject (http://doc.qt.io/qt-5/qandroidjniobject.html) --> that's a way to create instances of classes of the Java/Android-API. Furthermore you can call their methods - for example via

                                       QAndroidJniObject::callObjectMethod(const char *methodName, const char *signature, ... ) 
                                      

                                      That means that you first have to manage a Java surface object will be created. You do this via JNI. Then you can put this one as an argument to the ANativeWindow_fromSurface function.

                                      D Offline
                                      D Offline
                                      don-prog
                                      wrote on 4 May 2016, 22:35 last edited by
                                      #26

                                      @LuJoRi understood, via JNI :)
                                      But I still don't understand what I need to put in the ANativeWindow_fromSurface() function as first(JNIEnv * env) and second(jobject surface) argument?

                                      L 1 Reply Last reply 4 May 2016, 22:55
                                      0
                                      • D don-prog
                                        4 May 2016, 22:35

                                        @LuJoRi understood, via JNI :)
                                        But I still don't understand what I need to put in the ANativeWindow_fromSurface() function as first(JNIEnv * env) and second(jobject surface) argument?

                                        L Offline
                                        L Offline
                                        LuJoRi
                                        wrote on 4 May 2016, 22:55 last edited by LuJoRi 5 Apr 2016, 22:56
                                        #27

                                        @don-prog
                                        The first agrument requires something like a pointer on the Java environment which is needed because on Android even a Qt application is based on a JVM respectively ART (Android Runtime).
                                        The second one is the C++/Qt handle of the Java surface. Once you've retrieved it after your JNI calls, you can cast it to jobject type and then put it to the ANativeWindow_fromSurface function :)

                                        Unfortunately I'm short of time the next days (till sunday). Regardless I'd really like to help you! Feel free to ask if there are any questions :)

                                        D 1 Reply Last reply 4 May 2016, 23:05
                                        0
                                        • L LuJoRi
                                          4 May 2016, 22:55

                                          @don-prog
                                          The first agrument requires something like a pointer on the Java environment which is needed because on Android even a Qt application is based on a JVM respectively ART (Android Runtime).
                                          The second one is the C++/Qt handle of the Java surface. Once you've retrieved it after your JNI calls, you can cast it to jobject type and then put it to the ANativeWindow_fromSurface function :)

                                          Unfortunately I'm short of time the next days (till sunday). Regardless I'd really like to help you! Feel free to ask if there are any questions :)

                                          D Offline
                                          D Offline
                                          don-prog
                                          wrote on 4 May 2016, 23:05 last edited by
                                          #28

                                          @LuJoRi excuse for troubling! And what is the second argument in Qt exactly? I think it's not qwidget->winId(), so what?

                                          L 1 Reply Last reply 5 May 2016, 15:16
                                          0

                                          18/36

                                          4 May 2016, 07:06

                                          • Login

                                          • Login or register to search.
                                          18 out of 36
                                          • First post
                                            18/36
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups
                                          • Search
                                          • Get Qt Extensions
                                          • Unsolved