directshow.net

问题 I've been using DirectShow.NET to interface with a webcam in C# and so far everything has been going smoothly. However, right now I'm working on trying to set up a method to "crop" an image (while it's still being displayed as a webcam preview). Basically, I'm trying to show some kind of a mostly transparent image on top of the IVideoWindow object. Dealing with transparency in C#, however, has been pretty far from a cakewalk. So, how can I layer an Image object on top of an IVideoWindow?

问题 I am working on creating a video wall like application. The application creates multiple windows to display video and each window has its own filter graph. In a typical configuration, these windows would be spread over two displays for a total of 12 windows. But the problem is whenever I try to run the application, a few of the windows display black video. There are no crashes and each graph is rendered correctly without throwing any errors. The windows displaying the black video are random.

问题 Ok I have been at this for 2 days and need help with this last part. I have a Microsoft LifeCam Cinema camera and I use the .NET DirectShowLib to capture the video stream. Well actually I use WPFMediaKit, but I am in the source code of that dealing directly with the direct show library now. What I have working is: - View the video output of the camera - Record the video output of the camera in ASF or AVI (the only 2 MediaType's supported with ICaptureGraphBuilder2) The problem is: I can save

问题 I have found an example for accessing a webcam in C#. The example uses the DirectShow.NET library. I have tried to understand the code, but so far the only thing I could figure out is that somehow the usercontrol calls directshow to draw directly to the surface of the user control. I want to access each frame and put it into a Bitmap object. How can I tell when a new frame arrived? How can I capture this new frame into a Bitmap Object? This might be simple to answer if you know your way

问题 We would like to leverage the codec capabilities of DirectShow from Silverlight. Is this possible? 回答1: MediaStreamSource is really the closest you will get to accessing decoders in Silverlight. You also may want to look at this project: http://directshow4sl.codeplex.com/ It is a managed re-imagined version of DirectShow. 回答2: In short (because I can't even think of a long answer) no, you can't use DirectShow in Silverlight. 来源： https://stackoverflow.com/questions/3185302/using-directshow-api

问题 I currently have a working program which displays a preview from my webcam and uses the ISampleGrabberCB interface. Using the SampleCB my program converts the image to a bitmap and then processes the image for a barcode which is then decoded. This works perfectly when I show the result using a MessageBox however when I wish to edit a textbox on my main form with this result I get a few errors when I start my program. I am trying to update my text box using the following code within the

问题 I'm working on a .NET CF 2.0 application that uses the camera, showing the preview and allowing the user to take a photo. I'm using the CameraCaptureDialog component and I wanted to draw a rectangle on the preview screen, but I wasn't able to do it... Any ideas? Do you think the Overlay mixer filter in DirectShow can be useful? If so, do you have any example? (The problem is I work on the CF 2.0, so many solutions that work ok for the normal framework here don't work...). Thanks in advance,

问题 I'm trying to take pictures with a webcam in my c# application. I found out to use DirectShowLib. After a hard research, I found an example of how using the webcam, it displays the video on screen perfect, but it can't take the bitmap image for saving it at my will. sample of the code I found to take the picure would be public Bitmap snapImage() { IVMRWindowlessControl9 windowlessCtrl = null; IBaseFilter vmr9 = null; vmr9 = (IBaseFilter)new DirectShowLib.VideoMixingRenderer9(); DirectShowLib

问题 I'm trying to set up a subtitles file to DirectShow VSFilter programmatically. There is a way to do so through its property pages but I can't find any documentation regarding its API or even if it has one. Is there any sort of API, Interop, anything which would allow to set up a subtitle file for VSFilter? 回答1: There is no specific documentation on VSFilter, however it's open source software. So you can download source code, reference its interface definition e.g. in MPC-HC source \Mpc-hc\src

问题 I have a PC running Windows XP x64 and I am trying to record video+audio and closed caption from Analog TV using a USB PCTV (Conexant Polaris). As a initial test, I have built a simple graph in GraphStudio with the following chain of filters: Crossbar > Video Capture > CC Decoder > Line 21 Decoder > Video Renderer I can play this and see it render a video showing correct closed caption, but almost every time I hit stop in GraphStudio, the computer will freeze and I have to reboot it. I also