VS2010 problem with highgui.dll (Bug #286)

fixed in r3029

If you have the time maybe you can short explain why the
"extern "C" { +declspec(dllexport) unsigned int +lc_codepage = 0; } "
dll export magic makes the version switch obsolete

this bug still exists

this bug still exists

The bug can not be reproduced with the latest version from trunk: https://code.ros.org/svn/opencv/trunk

I ran laplace sample built in Win32 configuration with VS2010 on Windows 7, ran it on various videos from https://code.ros.org/svn/opencv/trunk/opencv_extra/testdata/python/videos. It works well. In order to reproduce the problem I need a sample video file that causes the crash. You can use VirtualDub to extract a small fragment from your video, if it's too big. Or send me the link to the video from where I can download it.

I am using OpenCV2.1 with VSExpress2010 on Windows 7 - 32 bit.

I first tried the pre-built libraries, all the C-style code worked well, but none of the C++ code did (would just crash whenever I called one of the functions that takes a string as an argument, e.g. imread, namedWindow etc.)

I wanted to use the C++ code, so I re-built OpenCV from source (from the download page) according to instructions on http://opencv.willowgarage.com/wiki/VisualC%2B%2B_VS2010_CMake, it all built without errors (except from the debug version of the python bindings). The C++ code such as imread and namedWindow started to work with the new dll's. However, VideoCapture::open(string) which calls cvCreateFileCapture() crashes, and now cvCreateFileCapture also does not work (it used to with the pre-built binaries). It does not return a NULL pointer (which I check for), it just crashes before returning anything.

I posted the previous message - I have the same exact problem on VSExpress2010 on a Windows XP machine with OpenCV2.1. However, the crash does not occur while debugging (have checked with both VS2010 and Code::Blocks). Both the Release and Debug versions crash when run from the command line, but if you launch either with the debugger, they work fine - so it is not a problem with the compiler options. Could be a threading issue? I cannot be the only person with this problem since the same exact thing happens with two different machines.

I also met the same issue on my vs2010+opencv2.1, I found only the release build version has this issue, the debug version works well. And if I built release version of my test app linked with highui210d.lib, it will not meet this issue. So looks that debug version of highui lib has some issue.