directshow

I had to change to directshow for my eyetracking software due to the difficulties to change resolution of the camera when using c++ and opencv. Directshow is new to me and it is kind of hard to understand everything. But I found this nice example that works perfectly for capturing & viewing the web cam. http://www.codeproject.com/Articles/12869/Real-time-video-image-processing-frame-grabber-usi I am using the version that not requires directShow SDK. (But it is still directshow that is used in the example, right??) #include <windows.h> #include <dshow.h> #pragma comment(lib,"Strmiids.lib")

I am using Media Foundation to play videos. On windows 7 some videos encoded with Mpeg1/Mpeg2 PS and Windows Media Player can play them, but Media Foundation does not(I tried to register a stub MPEG1Source but it still does not work). I noticed some of these files could be played with directshow but not Media foundation(can not be open at all). I guess "media player" does not use Media Foundation only? Is it possible to use Media Foundation to play these file? If it is not, how does Media player work? Thanks a lot. P.S. I have read the windows SDK and I registered a "fake" mpeg1 decode and it

I've written a filter that implements IStream (the COM interface not the C++ standard library class). That's all working well but my problem is that I'm not sure when (if ever) I can be sure than no further IStream commands will be sent so the stream behind IStream can be closed. The simplest place to close the stream would be in Stop() on my filter but this is too early. According to MSDN docs, the filter graph manager will call Stop() on filters in the graph in upstream order so my filter will get Stopped before an upstream mux filter which typically will use IStream to do any end of

I'm messed up with codec issue for days, and still couldn't see the big picture yet. It is my first time to deal with audio/video formats and codecs. So I really need some help about that. Here is the work. I'm writing several components that is responsible for encoding and decoding customized mpeg files. On top of standart de/compression process (for both audio and video) i will implement some custom de/encryption. Writing both codec and software libraries for this. Things i can't figure out are listed. For WMP, what is the codec locating policy. How do I differantiate my custom file format

I am trying to change the default webcam resolution using DirectShowNet in C#, from what I gather I need to change it from calling the built in VideoInfoHeader class in windows win32 api dll for avi capture. I have the following code from DirectShowNet: hr = capGraph.SetFiltergraph( graphBuilder ); if( hr < 0 ) Marshal.ThrowExceptionForHR( hr ); 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 =

I want to capture a current frame and its previous one to do analysis and produce a new frame to show. Is it to say I must write a transform DirectShow filter? But I am a newbie to DirectShow. I was confused by MSDN's lots of documents. So I wonder if there is any simple example to show how to do it. Thanks. Cook Goz In the directshow samples that come with the Platform SDK you, at least, always USED to get examples on how to make all sorts of filters. I can't believe they would have removed that. It made DirectShow almost usable :) This may help: Writing Transform Filters EZRGB24 Filter

I'm working on a solution that will be used to receive video stream from remote hosts and to put various texts on the top of it. Currently it consists of custom DirectShow push filter (C++) which receives data from remote hosts using RTP protocol and tiny C# application that sets up the DirectShow graph and is used as a container for the video. I'm using DirectShowLib interop library. However, I'm not sure how to pass parameters from this C# app to my custom filter. What are possible ways to do it? the simplest way is to register your own protocol (create a key myproto under HKCR, and then

I have started a thread on this at DirectShow.NET's forum, here is the link http://sourceforge.net/projects/directshownet/forums/forum/460697/topic/5194414/index/page/1 but unfortunately the problem still persists... I have an application that captures video from a webcam and audio from the microphone and save it to a file, for some reason the audio and video are never in-sync, i tried the following: 1. Started with ffdshow encoder and changed to AVI Mux - problem persists, audio is delayed and at the end of the video the picture remains frozen and the audio continues 2. Changed from AVI Mux