FAQ (Frequently Asked Questions)
Q1: Where do I submit Bug reports for the computer vision library?
A1: Send email to Subject: BUG <....your title...>
Q2: How do I send bug reports for the Intel� Image Processing Library?
A2: Submit your issue to Intel� Premier Support. More information regarding account registration, product authorization can be found at Intel� Performance Tools support page.
Q3: How do I join the web group for the library?
A3: Send email to , after you are a member and select your logon, you can read the web group at http://www.yahoogroups.com/group/OpenCV **.
Q4: How do I modify the web group so that I don't receive email everyday?
A4: To get the messages real time, or once a day as a daily digest, you can go to http://www.yahoogroups.com/mygroups ** and choose your setting from the pull down list to the right of OpenCV.
Q5: How do I get support for the Image Processing Library (IPL)?
A5: For the Image Processing Library for Windows, all support questions should go through:
the Image Processing Library.
Q6: I was a member of egroups and now I can't get in because it is now yahoogroups.
A6: Go to **, press the "Welcome Egroups Members!" button at upper right and follow the instructions to convert your account. If you are not a member of yahoo, you will need to join (free).
Windows* OS related Qs:
Q1: When I try to build one of the apps, I get an error, streams.h not found?
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 6.x), that can be downloaded from http://microsoft.com/directx/homeuser/downloads/default.asp ** This SDK can be used under NT 4.0 without any problem. 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.
Q2: I've installed the DirectX Media SDK, but get build problems.
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.
Q3: Where can I find out about compatible USB Cameras?
A3: look at http://web2.airmail.net/mprater/101/ ** There are a lot of USB camera (often called WebCams) links there.
Q4: When I build a filter graph with a USB camera, there are no output pins!? (Happens with Win2000* 3Com* camera).
A4: You can get the output pins to appear by selecting "refresh" from the graphedt.exe** menu.
Q5: How do you set the video format (e.g., resolution) of a WDM* video capture source camera within GraphEdit* (Filter Graph Editor)?
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.
Q6: When I try to register a filter or install the library, I get an "IPL Waterfall" error, what's up?
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.
Q7: How do I register a directShow filter?
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.
Q8: regsvr32 <filtername.ax> fails. What to do?
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.
Q9: I get: LINK : fatal error LNK1104: cannot open file "cvd.lib" Error executing link.exe. Where can I get this lib from?
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.
Linux* Related Qs:
Q1: Do you know, if there exist any Linux drivers for USB cameras and/or for Matrox MeteorII boards?
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.
Q2: I want a Linux version of the Intel� Image Processing Library, where do I get this?
A2: OpenCV no longer depends on the Image Processing Library. The Linux version of the Image Processing Library is not yet available. Questions or comments should be directed to: Intel® Image Processing Library. An alternative is to get optimized image processing functions from the Performance Primitives functions at http://developer.intel.com/software/products/ipp/. These support both WinOS and Linux today.
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