I'm a complete noob using openCV and openMP and I really want to understand why the cvSetCaptureProperty is not working with openMP. I'm using OpenCV and OpenMP on Visual Studio 2012.
My code:
#pragma omp parallel
for (int i=0;i<3600;i++)
{
cvSetCaptureProperty(capture, CV_CAP_PROP_POS_FRAMES,i);
frame = cvQueryFrame(capture);
i++;
}
The error message it returns me:
Unhandled exception at 0x71648EAB (opencv_ffmpeg248.dll) in pupilometry.exe: 0xC0000005: Access violation writing location 0xFEEEFEF6.
Someone know how to use cvSetCaptureProperty in a parallel way?
Thanks
Related
I've recently started exploring and reading about Microchip's PIC32 MCUs, most specifically for motor control. I had some job done over the years but was a long while and haven't used the IDE with evaluation board since university years. Been using Arduino-compatible boards since or boards, compatible with the Arduino IDE.
So I'm running MPLAB X IDE v6.05 with the latest XC32 Compiler.
My Development board is DT100113 Curiosity Pro board, utilizing PIC32MK0512MCJ064 MCU and an on-board PicKit4 (PKoB4) for programming/debugging/serial connection purposes.
What I try to do is light up the two user LEDs on pins RA10 and RE13 respectively.
As I begin with creating new project, select my device, my program/debug tool and give my project a name, next step is to create a new main.c file.
I create the file and write the following:
#include <stdio.h>
#include <stdlib.h>
#include <xc.h>
int main(int argc, char** argv) {
//Define corresponding port bits as outputs (0 = output, 1 = input).
TRISAbits.TRISA10 = 0;
TRISEbits.TRISE13 = 0;
//Latch the outputs to HIGH (1) and hold.
while(1)
{
LATAbits.LATA10 = 1;
LATEbits.LATE13 = 1;
}
return (EXIT_SUCCESS);
}
When I build and run it - nothing happens. Build is successful, connected to programmer, erase/flash device OK, but nothing with the LEDs.
I think I'm missing the #pragma directives (read about that it must be defined first prior anything else), but am unaware on how to set configuration bits (used peripherals, internal clock speed, etc.).
Any pointers to how-to articles, posts, etc. will be highly appreciated. I was not able to find step-by-step tutorial for my development board so far :((
Thank you in advance!
Cheers,
Iliyan
I tried creating a new project, it compiled and ran, but the LEDs were not lit.
Obviously was missing some vital parts in the code.
Application software examples and driver libraries are included as part of the MPLAB Harmony V3 Framework. Add Harmony to 'Embedded' under the 'Tools' tab of the MPLAB IDE.
In my project i used CvPoint2D64f* function to store corners of the chessboard image manually.Now i got memory leak error due to un released memory.I tried both free(Corners) and
delete[] Corners.But after 11 hours it gives same memory leak error.i had a confusion.Which one is correct method to release memory?
int main()
{
CvPoint2D64f* Corners = 0;
Corners = new CvPoint2D64f[25];
......
free(Corners);
return;
}
i used c library of opencv 2.1
Thanks in advance..
if you want it to be 'C', you can't use 'new', that has to be:
Corners = (CvPoint2D64f*) malloc(25 * sizeof(CvPoint2D64f));
...
free(Corners);
but honestly, your problems are due to using an outdated version(2.1) and an outdated api(c)
those manual memory management issues were the main reason for the opencv devs to switch to c++.
In clang, is there a way to enable bounds checking for [] access to std::vectors and other STL containers, preferably when building in debug mode only?
I just spent hours hunting down a subtle bug that turned out to be caused by us accessing past the end of a std::vector. It doesn't need to do anything clever when it detects the error, just trap in the debugger so that I can find out where it happened and fix it in the code.
Is there a way to do this other than "create your own type that inherits from std::vector", which I'd like to avoid?
(I'm using clang version 3.1 if that makes a difference.)
libstdc++ has a mature debug mode using -D_GLIBCXX_DEBUG.
libc++ also has a debug mode using -D_LIBCPP_DEBUG but as we can see this mailing list discussion: Status of the libc++ debug mode it is incomplete:
| My understanding is that this work was never completed and it's
probably broken/incomplete.
That is correct.
It’s on my list of things to fix/implement, but it’s not something that I will get to anytime soon.
It does seem to work for std::vector on 3.4 and up see it live, give the following program:
#include <vector>
#include <iostream>
int main()
{
std::vector<int> v = {0,1,2,3} ;
std::cout << v[-1] << std::endl ;
}
it generates the following error:
vector[] index out of bounds
Aborted
If you're using Linux or OS X you should look into the address sanitizer:
http://clang.llvm.org/docs/AddressSanitizer.html
It introduces a 2x slowdown, but does a bunch of memory checking and may catch your bug.
Another amazing tool that has saved me countless times is valgrind. If you can run with valgrind it will catch a ton of memory bugs and leaks.
#define _GLIBCXX_DEBUG
This enables all kinds of inline checking (see vector and debug/vector)
How to handle opencv gpu exceptions? Is there any specific set of error code api for opencvgpu exception handling?
I tried searching a lot but I only got 1 error code i.e. CV_GpuNotSupported.
Please help me out.
While I'm assuming that you know that CV_GpuNotSupported is NOT how OpenCV handles GPU exceptions, and in fact, it handles error when you try to call gpu methods without compiling OpenCV with -DHAVE_CUDA or -DHAVE_OPENCL, the way OpenCV (I also assume the newest OpenCV released version, 2.4.5) handles error codes, is defined in these files:
For methods that use NVIDIA CUDA:
https://github.com/Itseez/opencv/blob/2.4.5/modules/gpu/src/error.cpp
https://github.com/Itseez/opencv/blob/2.4.5/modules/gpu/src/precomp.hpp
For methods that use OpenCL:
https://github.com/Itseez/opencv/blob/2.4.5/modules/ocl/src/error.cpp
https://github.com/Itseez/opencv/blob/2.4.5/modules/ocl/src/precomp.hpp
As for the API, you can use cv::gpu::error or cv::ocl::error. Or to get the error string, getErrorString for cv::gpu and getOpenCLErrorString. And by the way for CUDA's error you have to specify whether it's an NPP, NCV, cufft, or cublas error.
I am trying to do simple image processing with OpenCV and the cvBlobsLib in Visual C++ 2008, and I get an error message when I try to create a CBlobResult object
IplImage* original = cvLoadImage("pic6.png",0);
cvThreshold(original, original, 100, 255, CV_THRESH_BINARY);
CBlobResult blobs = CBlobResult(original, NULL, 255);
The message is the following:
Run-Time Check Failure #2 - Stack around the variable blobs was corrupted
Why does this happen? How should I create this object? Thank you very much for your help.
Sorry. Actually it was my fault. I was trying to compile the debug version of my project with the release version of the cvBlobsLib library. As soon as I linked the debug version it worked.