Opencv resize() function cost graphic memory

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Hi, I just use cv::resize() function to resize an image. And it turns out that it will occupy GPU graphic memory.

cv::resize(mat, mat, cv::Size(1920,1080)) occupies 147MB.

System Info:

Opencv 3.3.1 without CUDA support. (cv::cuda::setDevice() gives "opencv is compiled without CUDA")

CUDA 10.0

How does this happen and how to solve the problem, besides version update/backup?