OpenCV error with Numpy 3d array

I am using this project to perform super resolution: [login to view URL] I want to use the high resolution image with OpenCV, but it keeps failing. I edited some parts of the code to return the variable 'image' in the method do_for_file. The object is a ndarray of floats of shape (x,y,3), I am assuming in an RGB image, but I am not sure. The error comes when I use: img_gris = [login to view URL](imgSR, cv2.COLOR_RGB2GRAY) [login to view URL]: OpenCV(4.1.2) /io/opencv/modules/imgproc/src/[login to view URL]: error: (-2:Unspecified error) in function 'cv::impl::{anonymous}::CvtHelper<VScn, VDcn, VDepth, sizePolicy>::CvtHelper(cv::InputArray, cv::OutputArray, int) [with VScn = cv::impl::{anonymous}::Set<3, 4>; VDcn = cv::impl::{anonymous}::Set<1>; VDepth = cv::impl::{anonymous}::Set<0, 2, 5>; cv::impl::{anonymous}::SizePolicy sizePolicy = (cv::impl::<unnamed>::SizePolicy)2u; cv::InputArray = const cv::_InputArray&; cv::OutputArray = const cv::_OutputArray&]' > Unsupported depth of input image: > 'VDepth::contains(depth)' > where > 'depth' is 6 (CV_64F) I tried to convert the floats to int, but then it showe the next error: img_gris = [login to view URL](img, cv2.COLOR_BGR2GRAY) [login to view URL]: OpenCV(4.1.2) /io/opencv/modules/imgproc/src/[login to view URL]: error: (-2:Unspecified error) in function 'cv::impl::{anonymous}::CvtHelper<VScn, VDcn, VDepth, sizePolicy>::CvtHelper(cv::InputArray, cv::OutputArray, int) [with VScn = cv::impl::{anonymous}::Set<3, 4>; VDcn = cv::impl::{anonymous}::Set<1>; VDepth = cv::impl::{anonymous}::Set<0, 2, 5>; cv::impl::{anonymous}::SizePolicy sizePolicy = (cv::impl::<unnamed>::SizePolicy)2u; cv::InputArray = const cv::_InputArray&; cv::OutputArray = const cv::_OutputArray&]' > Unsupported depth of input image: > 'VDepth::contains(depth)' > where > 'depth' is 4 (CV_32S) I want to use the high resolution image in my code without saving a .jpg file and calling [login to view URL]()