下面DirectShow Capture列子中关于如何用代码调节Brightness的一些问题? Easy

[无敌魔仙]

下面代码摘之DirectX C++文档
有几处疑惑,请高人解答
1.hr = pCap->QueryInterface(IID_IAMVideoProcAmp, (void**)&pProcAmp);句的pCap是什么东东,为何我尝试了很多都没有办法修改Brightness
2.m_pProcAmp->GetRange(VideoProcAmp_Brightness, &Min, &Max, &Step,
&Default, &Flags);此处的m_pProcAmp是pProcAmp吗,还是什么东东
3.如果那位能提供DirectShow Capture的设置比如Brightness,contrast, hue, saturation, gamma, and sharpness等参数的源代码,四百分感谢!


HWND hTrackbar; // Handle to the trackbar control.
// Initialize hTrackbar (not shown).

// Query the capture filter for the IAMVideoProcAmp interface.
IAMVideoProcAmp *pProcAmp = 0;
hr = pCap->QueryInterface(IID_IAMVideoProcAmp, (void**)&pProcAmp);
if (FAILED(hr))
{
// The device does not support IAMVideoProcAmp, so disable the control.
EnableWindow(hTrackbar, FALSE);
}
else
{
long Min, Max, Step, Default, Flags, Val;

// Get the range and default value.
hr = m_pProcAmp->GetRange(VideoProcAmp_Brightness, &Min, &Max, &Step,
&Default, &Flags);
if (SUCCEEDED(hr))
{
// Get the current value.
hr = m_pProcAmp->Get(VideoProcAmp_Brightness, &Val, &Flags);
}
if (SUCCEEDED(hr))
{
// Set the trackbar range and position.
SendMessage(hTrackbar, TBM_SETRANGE, TRUE, MAKELONG(Min, Max));
SendMessage(hTrackbar, TBM_SETPOS, TRUE, Val);
EnableWindow(hTrackbar, TRUE);
}
else
{
// This property is not supported, so disable the control.
EnableWindow(hTrackbar, FALSE);
}
}

[cnpr]

http://www.eaoo.com/design/list.asp?classid=2&Nclassid=13

[zxyin1]

关注，这段文档具体在哪部分呀

[无敌魔仙]

在 DirectShow文档的Configure the Video Quality里面

[无敌魔仙]

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