set HOG true,but errors occurs that cvFilter2D

[guyiyifeurach]

I use the KCV to track the moving object.When I set HOG false,it behaves very well,and peak_value set originally is 2.When set HOG false,the compiler returns the following errors.

OpenCV Error: Assertion failed (src.size() == dst.size() && src.channels() == dst.channels()) in cvFilter2D, file /opencv-2.4.13/opencv/modules/imgproc/src/filter.cpp, line 3359
terminate called after throwing an instance of 'cv::Exception'
what(): /opencv-2.4.13/opencv/modules/imgproc/src/filter.cpp:3359: error: (-215) src.size() == dst.size() && src.channels() == dst.channels() in function cvFilter2D.

I check the cvFilter2D,and image I use to init the KCFTracker and used to update the Rect are all gray images, and the size are also right.I am curious.
Do some friends know the reasons?
Thank you in advance!

[guyiyifeurach]

OK,when I have asked the question,I get the answer.Also to let more people know the reason I met the question.
#16