Debug Assertion Failed OpenCv is_block_type_valid(header->_block_use)
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I am new to Programming using Visual Studio and openCv. I wrote a simple program to display the red channel of an image, but every time i run the code it throws "DEBUG ASSERTION FAILED" error.
#include
#include
#include
using namespace std;
using namespace cv;
int main() {
Mat image;
image = imread("C:/Users/siddartha/Pictures/sample.jpg");
if (!image.data) {
cout = 3) {
vector rgb;
split(image, rgb);
namedWindow("r");
imshow("r", rgb[0]);
}
}
while (1);
return 0;
}
Error:
Debug Assertion Failed!
Program: ...sual Studio 2015\Projects\sampleOpenCV\Debug\sampleOpenCV.exe
File: minkernel\crts\ucrt\src\appcrt\heap\debug_heap.cpp
Line: 892
Expression: is_block_type_valid(header->_block_use)

c++
opencv
visual-studio-2015
visual-studio-debugging
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Are you absolutely sure that the image has been loaded correctly?
I would think that it hasn't been loaded correctly and because of that the vectorrgb
is empty and, in turn, the element rgb[0]
doesn't exist which triggers the exception ...
A couple of things I noted:
-
Use slashes (/
) for include-statements not backslashes (\
), i.e.
#include // Bad!
#include // Good!
-
In your check
if (!image.data) { ... }
do not assume that image.data
is set to NULL
ornullptr
for empty images. Instead check
if (!image.empty()) { ... }
-
Make sure that calls to cv::imshow(...)
are followed by a call tocv::waitKey( /* delay in ms or 0 to wait for user input */ )
, cf. the note in theOpenCV reference.
-
while (1);
-- is that intentional? What you want is probably cv::waitKey( 0 )
(see 3.).
UPDATE:
-
Make sure the vector rgb
has been initialized to the number of channels, i.e.
vector rgb(image.channels());
split(image, rgb);
// ...
UPDATE 2:
Can you tell me what exactly the error meant ?
Three things:
- The default constructor of
std::vector
creates an empty vector. - Apparently,
cv::split()
expects the caller, i.e. you, to allocate data for the output. If you fail to do so, it's likely provoke asegmentation fault. - For debug builds some compilers add padding or safety memory around objects in memory which is never to be touched. If this padding memory is altered at runtime, the program "knows" that something bad happened and throws an exception like the one you saw.
answered
Jan 13 '16 at 8:51
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it is compiling just fine for me. I am on visual-studio-2013.
here you have a case similar to yours, maybe it will help: debug-assertion-failed
answered
Jan 13 '16 at 8:15