Issues using cvtColor with Mat of CV_8U












0















I am using a black/white camera for a research project and am updating existing code from a previous individual. In multiple attempts to run the following program, I continue to hit a breakpoint within the line containing cvtColor.



pin_ptr<System::Byte> pinPtrArray;
pinPtrArray = &e->GetImageData->dataRawPixels1Byte[0];
Mat im(e->Width,e->Height, CV_8U, pinPtrArray);

Mat color, thresh;
cvtColor(im, color, COLOR_BGR2GRAY);
threshold(color, thresh, 110, 255, THRESH_BINARY);
imshow("thresh", thresh);
waitKey(20);


This portion is within a continuous 'for' loop taking images from an external camera, not the computer's webcam. If anyone could explain why I might be hitting this roadblock or notices incorrect in how I have initialized objects, that would be greatly appreciated. Thx!










share|improve this question























  • You've got a BW camera, and create a single channel Mat from the data you received. So, why is the first thing you do with it an attempt to convert it from BGR to grayscale? (Also, it's rather puzzling why you'd call the variable to hold the result of such operation "color")

    – Dan Mašek
    Nov 14 '18 at 21:05













  • @DanMašek, I probably should have excluded that from the sample and should have restated for threshold. I am having the same issue when removing cvtColor with the same error of "System.AccessViolationException: 'Attempted to read or write protected memory'". I believe it most likely has to do with how I am originally formatting my Mat container.

    – NewToLiving
    Nov 14 '18 at 21:17













  • In that case it would seem to be related to your e object. Hard to say without a lot more details. I suggest you edit your question and add relevant details (such as the specific error you receive, since that's quite significant).

    – Dan Mašek
    Nov 14 '18 at 21:23






  • 1





    if there are 3*width*height elements in pinPtrArray then choose Mat im(e->Width,e->Height, CV_8UC3, pinPtrArray); to signalize it is a color image in the beginning. If there is only one channel you can't convert BGR2GRAY

    – Micka
    Nov 14 '18 at 22:01
















0















I am using a black/white camera for a research project and am updating existing code from a previous individual. In multiple attempts to run the following program, I continue to hit a breakpoint within the line containing cvtColor.



pin_ptr<System::Byte> pinPtrArray;
pinPtrArray = &e->GetImageData->dataRawPixels1Byte[0];
Mat im(e->Width,e->Height, CV_8U, pinPtrArray);

Mat color, thresh;
cvtColor(im, color, COLOR_BGR2GRAY);
threshold(color, thresh, 110, 255, THRESH_BINARY);
imshow("thresh", thresh);
waitKey(20);


This portion is within a continuous 'for' loop taking images from an external camera, not the computer's webcam. If anyone could explain why I might be hitting this roadblock or notices incorrect in how I have initialized objects, that would be greatly appreciated. Thx!










share|improve this question























  • You've got a BW camera, and create a single channel Mat from the data you received. So, why is the first thing you do with it an attempt to convert it from BGR to grayscale? (Also, it's rather puzzling why you'd call the variable to hold the result of such operation "color")

    – Dan Mašek
    Nov 14 '18 at 21:05













  • @DanMašek, I probably should have excluded that from the sample and should have restated for threshold. I am having the same issue when removing cvtColor with the same error of "System.AccessViolationException: 'Attempted to read or write protected memory'". I believe it most likely has to do with how I am originally formatting my Mat container.

    – NewToLiving
    Nov 14 '18 at 21:17













  • In that case it would seem to be related to your e object. Hard to say without a lot more details. I suggest you edit your question and add relevant details (such as the specific error you receive, since that's quite significant).

    – Dan Mašek
    Nov 14 '18 at 21:23






  • 1





    if there are 3*width*height elements in pinPtrArray then choose Mat im(e->Width,e->Height, CV_8UC3, pinPtrArray); to signalize it is a color image in the beginning. If there is only one channel you can't convert BGR2GRAY

    – Micka
    Nov 14 '18 at 22:01














0












0








0








I am using a black/white camera for a research project and am updating existing code from a previous individual. In multiple attempts to run the following program, I continue to hit a breakpoint within the line containing cvtColor.



pin_ptr<System::Byte> pinPtrArray;
pinPtrArray = &e->GetImageData->dataRawPixels1Byte[0];
Mat im(e->Width,e->Height, CV_8U, pinPtrArray);

Mat color, thresh;
cvtColor(im, color, COLOR_BGR2GRAY);
threshold(color, thresh, 110, 255, THRESH_BINARY);
imshow("thresh", thresh);
waitKey(20);


This portion is within a continuous 'for' loop taking images from an external camera, not the computer's webcam. If anyone could explain why I might be hitting this roadblock or notices incorrect in how I have initialized objects, that would be greatly appreciated. Thx!










share|improve this question














I am using a black/white camera for a research project and am updating existing code from a previous individual. In multiple attempts to run the following program, I continue to hit a breakpoint within the line containing cvtColor.



pin_ptr<System::Byte> pinPtrArray;
pinPtrArray = &e->GetImageData->dataRawPixels1Byte[0];
Mat im(e->Width,e->Height, CV_8U, pinPtrArray);

Mat color, thresh;
cvtColor(im, color, COLOR_BGR2GRAY);
threshold(color, thresh, 110, 255, THRESH_BINARY);
imshow("thresh", thresh);
waitKey(20);


This portion is within a continuous 'for' loop taking images from an external camera, not the computer's webcam. If anyone could explain why I might be hitting this roadblock or notices incorrect in how I have initialized objects, that would be greatly appreciated. Thx!







opencv c++-cli






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asked Nov 14 '18 at 19:53









NewToLivingNewToLiving

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184













  • You've got a BW camera, and create a single channel Mat from the data you received. So, why is the first thing you do with it an attempt to convert it from BGR to grayscale? (Also, it's rather puzzling why you'd call the variable to hold the result of such operation "color")

    – Dan Mašek
    Nov 14 '18 at 21:05













  • @DanMašek, I probably should have excluded that from the sample and should have restated for threshold. I am having the same issue when removing cvtColor with the same error of "System.AccessViolationException: 'Attempted to read or write protected memory'". I believe it most likely has to do with how I am originally formatting my Mat container.

    – NewToLiving
    Nov 14 '18 at 21:17













  • In that case it would seem to be related to your e object. Hard to say without a lot more details. I suggest you edit your question and add relevant details (such as the specific error you receive, since that's quite significant).

    – Dan Mašek
    Nov 14 '18 at 21:23






  • 1





    if there are 3*width*height elements in pinPtrArray then choose Mat im(e->Width,e->Height, CV_8UC3, pinPtrArray); to signalize it is a color image in the beginning. If there is only one channel you can't convert BGR2GRAY

    – Micka
    Nov 14 '18 at 22:01



















  • You've got a BW camera, and create a single channel Mat from the data you received. So, why is the first thing you do with it an attempt to convert it from BGR to grayscale? (Also, it's rather puzzling why you'd call the variable to hold the result of such operation "color")

    – Dan Mašek
    Nov 14 '18 at 21:05













  • @DanMašek, I probably should have excluded that from the sample and should have restated for threshold. I am having the same issue when removing cvtColor with the same error of "System.AccessViolationException: 'Attempted to read or write protected memory'". I believe it most likely has to do with how I am originally formatting my Mat container.

    – NewToLiving
    Nov 14 '18 at 21:17













  • In that case it would seem to be related to your e object. Hard to say without a lot more details. I suggest you edit your question and add relevant details (such as the specific error you receive, since that's quite significant).

    – Dan Mašek
    Nov 14 '18 at 21:23






  • 1





    if there are 3*width*height elements in pinPtrArray then choose Mat im(e->Width,e->Height, CV_8UC3, pinPtrArray); to signalize it is a color image in the beginning. If there is only one channel you can't convert BGR2GRAY

    – Micka
    Nov 14 '18 at 22:01

















You've got a BW camera, and create a single channel Mat from the data you received. So, why is the first thing you do with it an attempt to convert it from BGR to grayscale? (Also, it's rather puzzling why you'd call the variable to hold the result of such operation "color")

– Dan Mašek
Nov 14 '18 at 21:05







You've got a BW camera, and create a single channel Mat from the data you received. So, why is the first thing you do with it an attempt to convert it from BGR to grayscale? (Also, it's rather puzzling why you'd call the variable to hold the result of such operation "color")

– Dan Mašek
Nov 14 '18 at 21:05















@DanMašek, I probably should have excluded that from the sample and should have restated for threshold. I am having the same issue when removing cvtColor with the same error of "System.AccessViolationException: 'Attempted to read or write protected memory'". I believe it most likely has to do with how I am originally formatting my Mat container.

– NewToLiving
Nov 14 '18 at 21:17







@DanMašek, I probably should have excluded that from the sample and should have restated for threshold. I am having the same issue when removing cvtColor with the same error of "System.AccessViolationException: 'Attempted to read or write protected memory'". I believe it most likely has to do with how I am originally formatting my Mat container.

– NewToLiving
Nov 14 '18 at 21:17















In that case it would seem to be related to your e object. Hard to say without a lot more details. I suggest you edit your question and add relevant details (such as the specific error you receive, since that's quite significant).

– Dan Mašek
Nov 14 '18 at 21:23





In that case it would seem to be related to your e object. Hard to say without a lot more details. I suggest you edit your question and add relevant details (such as the specific error you receive, since that's quite significant).

– Dan Mašek
Nov 14 '18 at 21:23




1




1





if there are 3*width*height elements in pinPtrArray then choose Mat im(e->Width,e->Height, CV_8UC3, pinPtrArray); to signalize it is a color image in the beginning. If there is only one channel you can't convert BGR2GRAY

– Micka
Nov 14 '18 at 22:01





if there are 3*width*height elements in pinPtrArray then choose Mat im(e->Width,e->Height, CV_8UC3, pinPtrArray); to signalize it is a color image in the beginning. If there is only one channel you can't convert BGR2GRAY

– Micka
Nov 14 '18 at 22:01












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