void D3DPresentEngine::presentSample(void *opaque, qint64)
{
    HRESULT hr = S_OK;

    IMFSample *sample = reinterpret_cast<IMFSample*>(opaque);
    IMFMediaBuffer* buffer = NULL;
    IDirect3DSurface9* surface = NULL;

    if (m_surface && m_surface->isActive()) {
        if (sample) {
            // Get the buffer from the sample.
            hr = sample->GetBufferByIndex(0, &buffer);
            if (FAILED(hr))
                goto done;

            // Get the surface from the buffer.
            hr = MFGetService(buffer, MR_BUFFER_SERVICE, IID_PPV_ARGS(&surface));
            if (FAILED(hr))
                goto done;
        }

        if (surface && updateTexture(surface)) {
            QVideoFrame frame = QVideoFrame(new TextureVideoBuffer(m_glTexture),
                                            m_surfaceFormat.frameSize(),
                                            m_surfaceFormat.pixelFormat());

            // WMF uses 100-nanosecond units, Qt uses microseconds
            LONGLONG startTime = -1;
            if (SUCCEEDED(sample->GetSampleTime(&startTime))) {
                frame.setStartTime(startTime * 0.1);

                LONGLONG duration = -1;
                if (SUCCEEDED(sample->GetSampleDuration(&duration)))
                    frame.setEndTime((startTime + duration) * 0.1);
            }

            m_surface->present(frame);
        }
    }

done:
    qt_wmf_safeRelease(&surface);
    qt_wmf_safeRelease(&buffer);
    qt_wmf_safeRelease(&sample);
}