Question

I am using DirectShow.Net and I am capturing video from a webcam and saving it to an AVI file. AVI files can get large and I would like to save it in a different format. I am using ICaptureGraphBuilder2::SetOutputFileName( MediaSubType.type, name, out, out). ICaptureGraphBuilder will only let me use a MediaSubType of .AVI or .ASF to save a file. If i try to change the type it tries to save as, it will crash:

            graphBuilder = (IGraphBuilder) new FilterGraph();

        //Create the Capture Graph Builder

        ICaptureGraphBuilder2 captureGraphBuilder = null;
        captureGraphBuilder = (ICaptureGraphBuilder2) new CaptureGraphBuilder2();

        //Create the media control for controlling the graph
        mediaControl = (IMediaControl) this.graphBuilder;

        // Attach the filter graph to the capture graph
        int hr = captureGraphBuilder.SetFiltergraph(this.graphBuilder);
        DsError.ThrowExceptionForHR(hr);

        //Add the Video input device to the graph
        hr = graphBuilder.AddFilter(theDevice, "source filter");
        DsError.ThrowExceptionForHR(hr);


        //Add the Video compressor filter to the graph
        hr = graphBuilder.AddFilter(theCompressor, "compressor filter");
        DsError.ThrowExceptionForHR(hr);

        //Create the file writer part of the graph. SetOutputFileName does this for us, and returns the mux and sink
        IBaseFilter mux;
        IFileSinkFilter sink;
        hr = captureGraphBuilder.SetOutputFileName(MediaSubType.MPEG1Video, textBox1.Text, out mux, out sink);
        captureGraphBuilder.SetOutputFileName

        DsError.ThrowExceptionForHR(hr);


        //Render any preview pin of the device
        hr = captureGraphBuilder.RenderStream(PinCategory.Preview, MediaType.Video, theDevice, null, null);
        DsError.ThrowExceptionForHR(hr);

Is there a way to save to anything other then AVI or ASF without too much hassle?

Answer 1

The problem is most likely not the AVI container format but the codec that you are using to compress the video.

You will need to add a different video compression filter (probably MPEG4 or AVC) and wherever you get that will probably also supply an MP4 mux that you can and should use instead of the avi mux that you are using now.