hello everyone, I'm using DirectShow.net to capture images from a webCam, after searching
the web I got this code and it works fine: to see the original full code kindly
follow the link below
bool SetupGraph()
{
int hr;
try
{
hr = capGraph.SetFiltergraph(graphBuilder);
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
hr = graphBuilder.AddFilter(capFilter, "Ds.NET Video Capture Device");
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
DsUtils.ShowCapPinDialog(capGraph, capFilter, this.Handle);
AMMediaType media = new AMMediaType();
media.majorType = MediaType.Video;
media.subType = MediaSubType.RGB24;
media.formatType = FormatType.VideoInfo; // ???
hr = sampGrabber.SetMediaType(media);
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
hr = graphBuilder.AddFilter(baseGrabFlt, "Ds.NET Grabber");
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
Guid cat = PinCategory.Preview;
Guid med = MediaType.Video;
hr = capGraph.RenderStream(ref cat, ref med, capFilter, null, null); // baseGrabFlt
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
cat = PinCategory.Capture;
med = MediaType.Video;
hr = capGraph.RenderStream(ref cat, ref med, capFilter, null, baseGrabFlt); // baseGrabFlt
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
media = new AMMediaType();
hr = sampGrabber.GetConnectedMediaType(media);
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
if ((media.formatType != FormatType.VideoInfo) || (media.formatPtr == IntPtr.Zero))
throw new NotSupportedException("صيغه غير معروفه");
videoInfoHeader = (VideoInfoHeader)Marshal.PtrToStructure(media.formatPtr, typeof(VideoInfoHeader));
Marshal.FreeCoTaskMem(media.formatPtr); media.formatPtr = IntPtr.Zero;
hr = sampGrabber.SetBufferSamples(false);
if (hr == 0)
hr = sampGrabber.SetOneShot(false);
if (hr == 0)
hr = sampGrabber.SetCallback(null, 0);
if (hr < 0)
Marshal.ThrowExceptionForHR(hr);
return true;
}
catch (Exception ee)
{
MessageBox.Show(this, "Could not setup graph\r\n" + ee.Message, "DirectShow.NET", MessageBoxButtons.OK, MessageBoxIcon.Stop);
return false;
}
}
my problem is when I call this form from another form for a second time it gives
me this error: "Value does not fall within the expected range" when the compiler comes to this section:
hr = capGraph.RenderStream(ref cat, ref med, capFilter, null, null); actually i discovered that the problem disappear when I unplug the web-came physically
and plug it again, so I concluded that i need to unplug it using code so please
if u know tell me how to do it or if u have any better idea like how to restart
the stream please tell me you can access the original code on http://www.codeproject.com/script/Content/ViewAssociatedFile.aspx?rzp=%2FKB%2Fdotnet%2FROTEsys%2Frotesys_src.zip&zep=Tracking.cs&obid=9401&obtid=2&ovid=1[^]
thank you for ur time and patience