How to render filtergraph with FileWriter filter

Question

THe filter graphs renderer method takes a reference of a output pin. But the FileWriter Filter has no output pin. So how do i make the filter graph render itself?

HRESULT hr = pGraph->Render(FilefilterOutPin); //File Writer does not offer an outputpin

This is my code that builds the graph with its filters:

void static SaveFile()
{


    CoInitialize(NULL);
    IGraphBuilder *pGraph = NULL;
    IMediaControl *pControl = NULL;
    IMediaEvent *pEvent = NULL;

    HRESULT myhr = CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC_SERVER,
        IID_IFilterGraph, (void **) &pGraph);

    pGraph->QueryInterface(IID_IMediaControl, (void **)&pControl);
    pGraph->QueryInterface(IID_IMediaEvent, (void **) &pEvent);

    IBaseFilter *pFileWritter;
    IFileSinkFilter* fileSInk = NULL;
    CoCreateInstance(CLSID_FileWriter, NULL, CLSCTX_INPROC_SERVER, IID_IBaseFilter, (void **) &pFileWritter);
    pFileWritter->QueryInterface(IID_IFileSinkFilter, (void **) &fileSInk);



    fileSInk->SetFileName(L"C:\\TEMP\\yc1.avi", NULL);

    //get source out pin
    IBaseFilter *pSource;
    IPin* SourcePin;
    pGraph->AddSourceFilter(L"C:\\TEMP\\sample.avi", L"sample", &pSource);
    SourcePin = GetPin(pSource, PINDIR_OUTPUT);

    //AVI SPLITTER
    IBaseFilter *aviSplitter;
    CoCreateInstance(CLSID_AviSplitter, NULL, CLSCTX_INPROC_SERVER, IID_IBaseFilter, (void **) &aviSplitter);
    pGraph->AddFilter(aviSplitter, L"AVI-Splitter");
    IPin* avisplitIn;
    IPin* avisplitOut;

    avisplitIn = GetPin(aviSplitter, PINDIR_INPUT);
    avisplitOut = GetPin(aviSplitter, PINDIR_OUTPUT);
    pGraph->Connect(SourcePin, avisplitIn);

    //END


    //MyFilter//
    IBaseFilter *myFilter;

    CoCreateInstance(CLSID_MyFilter, NULL, CLSCTX_INPROC_SERVER, IID_IBaseFilter, (void **) &myFilter);

    IMyFilter *myfilterinterface;
    myFilter->QueryInterface(IID_IMyFilter, (void **) &myfilterinterface);
    myfilterinterface->StartRecording();
    pGraph->AddFilter(myFilter, L"MyFilter");
    IPin* myInputPin;
    IPin* myOutPutPin;
    myInputPin = myfilterinterface->GetMyPin(0);
    myOutPutPin = myfilterinterface->GetMyPin(3);

    pGraph->Connect(avisplitOut, myInputPin);
    //END//



    ///AVMUX
    IBaseFilter *avmux;
    CoCreateInstance(CLSID_AVIDec, NULL, CLSCTX_INPROC_SERVER, IID_IBaseFilter, (void **) &avmux);
    IPin* avmuxIn;
    IPin* avmuxOut;
    avmuxIn = GetPin(avmux, PINDIR_INPUT);
    avmuxOut = GetPin(avmux, PINDIR_OUTPUT);
    pGraph->AddFilter(avmux, L"AVmux");
    pGraph->Connect(myOutPutPin, avmuxIn);


    //END
    //get writer inpin
    IPin *writerPin;
    writerPin = GetPin(pFileWritter, PINDIR_INPUT);


    //connect pins
    pGraph->Connect(SourcePin, writerPin);

    //render
    HRESULT hr S_OK;
    if(SUCCEEDED(hr))
    {
        hr = pControl->Run();
        if(SUCCEEDED(hr))
        {
            long evCode;
            pEvent->WaitForCompletion(INFINITE, &evCode);
            myfilterinterface->StopRecording();
            myFilter->Release();
                   CoUninitialize();

        }
    }






}

This compiles and runs fine but doesn't produce any file.

Please Luke, stop posting thousands of basic questions about DirectShow. Read a book or a [tutorial](http://stackoverflow.com/questions/2077997/where-can-i-find-a-thorough-directshow-tutorial) about how DirectShow works. For basic questions try a directshow mailinglist or chat or forum. — CPlusSharp, Mar 03 '14 at 15:31

score 1 · Answer 1 · edited May 23 '17 at 11:49

1

Pins connect filter to enable them pass data one to another. File writer does not have anything to stream data to - instead it just writers to file. Hence, no output pin.

To specify the file name you use IFileSinkFilter::SetFileName interface (see When changing a file name, Recording Start is overdue for 3 seconds. OnTimer code snippet using it).

edited May 23 '17 at 11:49

Community

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1

answered Mar 01 '14 at 22:03

Roman R.

68,205
6
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So I don't have to call render? – Luke Mar 02 '14 at 10:48

score 1 · Answer 2 · answered Mar 03 '14 at 12:51

So if Im understanding correctly you want to render to screen AND render to file.

To do this you need to place an infinite pin tee in between your AVI splitter and your AVI mux. 1 output of the tee would continue to go to the AVI Mux and you can use another to stream to a video renderer (e.g a VMR9).

score 0 · Answer 3 · answered Mar 05 '14 at 19:49

Please read in MSDN what Render method does, it's not what you think. The closest thing to your idea is RenderStream (from a bit different interface, look it up) with the FileWriter in its last parameter. But please learn some DirectShow basics first.

score -1 · Answer 4 · answered Mar 01 '14 at 19:46

-1

First, FileWriter Filter only has input pin because it receives data and writes to a file.

Second, if you want to play a file you should use File Source (Async.) filter. So, create a instance of File Source (Async.), get it's output pin and pass to

pGraph->Render(FileSourceOutputPin);

Third, alternatively you can render file like this:

pGraph->RenderFile("C:\\test.avi", "");

answered Mar 01 '14 at 19:46

Mustafa Chelik

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I don't want to play a file. I want to create one! – Luke Mar 01 '14 at 19:53
So as I said in my comment, you should create input pin of FileWriter not output pin. – Mustafa Chelik Mar 01 '14 at 19:54
but how do I actually render the graph if filewriter has no output pin? – Luke Mar 01 '14 at 19:55
A graph's first filter creates data and passes forward until reaches to the last filter which receives it. That's it. You should set filename for FileWriter to write to file using input pin. – Mustafa Chelik Mar 01 '14 at 20:00
You don't understand my problem. I have to call Render to build the graph. But I need to pass render an output pin. However the last filter in my chain doesn't have an output pin! – Luke Mar 01 '14 at 20:01
This is C# form of setting filename property to FileWriter: (file_writer_filter as IFileSinkFilter).SetFileName( "c:\\a.avi", null); – Mustafa Chelik Mar 01 '14 at 20:02
that does not address my problem – Luke Mar 01 '14 at 20:03
If your last filter doesn't have an output pin, it means that your graph is complete. Now use pGraph->Run() to start your graph. – Mustafa Chelik Mar 01 '14 at 20:04
Can you write down your filters here? – Mustafa Chelik Mar 01 '14 at 20:12

How to render filtergraph with FileWriter filter

4 Answers4