Open Source Computer Vision LibrayFrequently Asked Questions |
A1: Send email to OpenCV@yahoogroups.com Subject: BUG <....your title...>
A2: Send email to developer_support@intel.com
A3: Send email to OpenCV-subscribe@yahoogroups.com, after you are a member and select your logon, you can read the web group at http://groups.yahoo.com/group/OpenCV **.
A4: To get the messages real time, or once a day as a daily digest, you can go to http://groups.yahoo.com/mygroups ** and choose your setting from the pull down list to the right of OpenCV.
A5: For the Image Processing Library, all support questions should go through:
http://support.intel.com/support/performancetools/support.htm (for release libraries)
https://premier.intel.com/scripts-quad/welcomeplsb.asp (for beta libraries)
A1: You need the direct show SDK for streams.h. You do not need DirectX* SDK for NT* 4.0 to compile and run DirectShow filters. You need only DirectX Media* SDK (version 5.x or higher), that can be downloaded from http://microsoft.com/directx/homeuser/downloads/default.asp ** This SDK can be used under Win98, NT 4.0 or Win2000 without any problem. Do not forget to put paths to the include subfolder and classes\base (in case of DirectX Media 5.x or 6.x) or samples\Multimedia\DirectShow\BaseClasses (in case of DirectX 8.x) subfolder to include paths in DevStudio* (they should go first in the list!!!) and lib subfolder to lib paths in DevStudio.
If you have DirectX 8.x, you should build base C++ library for Direct Show by yourself. In DevStudio open baseclasses.dsw workspace from samples\Multimedia\DirectShow\BaseClasses subfolder and build both release and debug configurations of the library. Finally, copy resulting strmbase.lib and strmbasd.lib libraries to lib subfolder of DirectX 8.x or OpenCV installation folder. That's it.
A2: Do not forget to put paths to the include subfolder and classes\base subfolder to include paths in DevStudio (they should go first in the list!!!) and lib subfolder to lib paths in DevStudio. Do not forget to build DirectShow C++ libraries. See the previous question as well.
A3: look at http://web2.airmail.net/mprater/101/ ** There are a lot of USB camera (often called WebCams) links there.
A4: You can get the output pins to appear by selecting "refresh" from the graphedt.exe** menu.
A5: Set the video format with the property page of the output pin of the capture source. Just click the right mouse button in GraphEdit on the output pin to display the property page. But make sure you do that before connecting the pin to other pins.
A6: IPL library has a bug in it, it uses a DLL switcher so that IPL.DLL replaces itself with the processor appropriate DLL (such as IPLA6.DLL for a PIII). The problem is, the DLL switcher looks only in the system path, not in the current directory. Thus, if the IPL DLL directory isn't in the system path, or you have a different version of IPL somewhere in front of the current directory in the system path, this error will occur. Solution: Get rid of other versions of IPL and change the system path to point to the correct IPL directory or move the IPL DLLs to a directory (system, system32) that is in the system path.
A7: Call up a command line prompt, cd to the directory the filter is in, run regsvr32 <filtername.ax>. Obviously, this will only work if regsvr32 is in your system path.
A8: Almost always means that some DLL the filter depends on is not being found in the local directory or the system path. If you have MSVC++* installed, you have a copy of a program called "depends.exe". Run this program on the offending filter. Missing DLLs will appear highlighted. Find these DLLs, move them to the local directory or system path and try regsvr32 again. Viola.
A9: It's the debug version of the library. Using MSVC++: Either: Under the Project menu, select Settings. Then select the Link tab and change the library to use to cv.lib; Or: Build a debug version of the library -- Under the build menu select "Set Active Configuration", click on "Debug" and the build all to build a debug version of cv.lib named cvd.lib. Another method is to just rename cv.lib to cvd.lib ... but you won't be able to debug.
A1: USB on Linux is just now maturing, but is doing so very quickly. The best site to visit is (URL:http://www.linux-usb.org/ ** ). Of specific interest is the link (URL:http://www.qbik.ch/usb/devices/ **), which has a video section. For the Matrox MeteorII, there appears to be a driver for the Linux4Video2 system, which is a more advanced video system being developed in parallel with the Linux4Video(1), included in the kernel. Details at (URL:http://www.thedirks.org/v4l2/ **). See the "People" section for the driver. A downside with V4L2 is that it's not yet working under 2.3.x or 2.4.x of the Linux kernel.