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我正在尝试使用DeckLink.net dll 在 C# 中重新创建来自 Blackmagic Design 的 DeckLink SDK 的 StreamingPreview 示例。

当我运行下面的代码时，它似乎工作：通知已安装，我什至收到设备到达事件（我也可以查询设备的属性）但我得到一个AccessViolationException。它必须连接到 streamingDiscovery.InstallDeviceNotifications() 行，并且只有在我实际插入设备并因此收到通知时才能得到它。

你能帮帮我吗？

我的 C# 代码：

class DeckLink : IBMDStreamingDeviceNotificationCallback
{
    // Native values
    private static int S_OK = 0;
    private static int E_FAIL = 1;

    int result;

    private IBMDStreamingDiscovery streamingDiscovery;

    public DeckLink()
    {
        try
        {
            streamingDiscovery = (IBMDStreamingDiscovery)new StreamingDiscovery();
        }
        catch (Exception)
        {
            Console.WriteLine("This application requires the Blackmagic Streaming drivers installed.\nPlease install the Blackmagic Streaming drivers to use the features of this application.");
            goto bail;
        }
        result = streamingDiscovery.InstallDeviceNotifications(this);
        if (result == E_FAIL)
        {
            Console.WriteLine("Failed to install device notifications for the Blackmagic Streaming devices");
            goto bail;
        }

        Console.WriteLine("Device notifications for the Blackmagic Streaming devices were successfully installed");
        return;

    bail:
        if (streamingDiscovery != null)
        {
            streamingDiscovery = null;
        }
        return;
    }

    public int StreamingDeviceArrived(Blackmagic.DeckLink.IDeckLink device)
    {
        Console.WriteLine("Device arrived");
        return S_OK;
    }

    public int StreamingDeviceModeChanged(Blackmagic.DeckLink.IDeckLink device, Blackmagic.DeckLink.BMDStreamingDeviceMode mode)
    {
        throw new NotImplementedException();
    }

    public int StreamingDeviceRemoved(Blackmagic.DeckLink.IDeckLink device)
    {
        throw new NotImplementedException();
    }
}

这些来自 SDK 的 C++ 示例：

result = CoCreateInstance(CLSID_CBMDStreamingDiscovery, NULL, CLSCTX_ALL, IID_IBMDStreamingDiscovery, (void**)&m_streamingDiscovery);
if (FAILED(result))
{
    MessageBox(_T("This application requires the Blackmagic Streaming drivers installed.\nPlease install the Blackmagic Streaming drivers to use the features of this application."), _T("Error"));
    goto bail;
}

// Note: at this point you may get device notification messages!
result = m_streamingDiscovery->InstallDeviceNotifications(this);
if (FAILED(result))
{
    MessageBox(_T("Failed to install device notifications for the Blackmagic Streaming devices"), _T("Error"));
    goto bail;
}

C++ 查询接口：

if (ppv == NULL)
    return E_POINTER;
*ppv = NULL;

if (iid == IID_IUnknown)
{
    *ppv = static_cast<IUnknown*>(static_cast<IBMDStreamingDeviceNotificationCallback*>(this));
    AddRef();
    result = S_OK;
}
else if (iid == IID_IBMDStreamingDeviceNotificationCallback)
{
    *ppv = static_cast<IBMDStreamingDeviceNotificationCallback*>(this);
    AddRef();
    result = S_OK;
}
else if (iid == IID_IBMDStreamingH264InputCallback)
{
    *ppv = static_cast<IBMDStreamingH264InputCallback*>(this);
    AddRef();
    result = S_OK;
}

return result;

我还在这里上传了 SDK 的示例和 dotNet 库。

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0 回答 0