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How can add VoIP development kit?

  • I am working on a soft phone project. In this project I want to use the VoIP Development Kit. But I don't know how to add this library to my QtSDK. Anyone can help me in this issue? To be specific I put that library in my SDK in different locations. But all the it gives the same error that VDKQtengine was declared with no type. What is the procedure to add this kit to my SDK? Do I have to call it in the project file? If so, then how could be it done?

  • I have solved the problem by including INCLUDE PATH as the VDK directory. But I am also having another problem. When I try to compile my project it shows 2 errors like:
    @:-1: error: cannot find -lvdk
    :-1: error: collect2: ld returned 1 exit status@

    and my project file is like:
    @TEMPLATE = app
    TARGET = Server
    QT += network

    INCLUDEPATH += C:/Program Files/Voip Development Kit

    LIBPATH += C:/Program Files/Voip Development Kit

    LIBS += -lvdk -lsofia-sip-ua -lspeex -lspeexdsp -ljrtp -lportaudio

    HEADERS += testwidget.h
    SOURCES += testwidget.cpp

    FORMS += testwidget.ui@

    Are there someone one who can help on this issue?

  • @
    LIBS += -L"C:/Program Files/Voip Development Kit"
    LIBS += -lvdk -lsofia-sip-ua -lspeex -lspeexdsp -ljrtp -lportaudio

  • Thanks cincirin. That was helpful. But Now it is showing a similar problem. Its kind of funny by the way.
    :-1: error: cannot find -lsofia-sip-ua
    :-1: error: collect2: ld returned 1 exit status@

  • You must add new paths for additional search libraries.
    Something like ...
    LIBS += "Your path to Sofia SIP User Agent Library"
    ... and the same for all others additional libraries directories

  • Where are all those libraries located? You need to add the proper -L flags to LIBS.

  • [quote author="peppe" date="1326033725"]You need to add the proper -L flags to LIBS.[/quote]

    oh, my bad. So yes, you need to add -L flag before the libraries path.

  • Hello Cincirin,
    Is it like

    @LIBS += -L"C:/Program Files/Voip Development Kit"
    LIBS += -L"C:/Program Files/Voip Development Kit/lvdk"
    LIBS += -L"C:/Program Files/Voip Development Kit/lsofia-sip-ua"
    LIBS += -L"C:/Program Files/Voip Development Kit/lspeex"
    LIBS += -L"C:/Program Files/Voip Development Kit/lspeexdsp"
    LIBS += -L"C:/Program Files/Voip Development Kit/ljrtp"
    LIBS += -L"C:/Program Files/Voip Development Kit/lportaudio_x86"@

    In C:/Program Files/Voip Development Kit location the libs are named like


    Is this environment right to build the project?

  • Hi.
    You must tell the compiler where the *.lib files are located and not the *.dll files. So where are these *.lib located ? (e.g. libsofia_sip_ua.lib, portaudio_x86.lib, libjrtp.lib, etc. ...). From what I understand from your previous post, vdk.lib is located in "C:/Program Files/Voip Development Kit" directory ...
    LIBS += -L"C:/Program Files/Voip Development Kit"
    LIBS += -lvdk
    you said it works. Now you can add other *.lib to additional project dependencies:
    LIBS += -lsofia-sip-ua -lspeex -lspeexdsp -ljrtp -lportaudio
    BUT you must add the additional *.lib search directories. Something like:
    LIBS += -L"where issofia-sip-ua.lib located" -L"where is speex.lib located" ... etc

    Also, after your project will compile properly, you need to copy all *.dll where your application executable is located. Or you can add new environment path pointed to "C:/Program Files/Voip Development Kit"

  • Visit this website:
    You can find a lot of useful information on VoIP technology. You can try out samples if you wish. Clear descriptions and documentation belong to all examples. You can use free source codes as well.

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