How to solve Error "Error using strfind Conversion to double from VideoReader is not possible."?

I'm trying to read RGB frames from a video to do some work on them and compile a new video. here's my code:

 videoObj = VideoReader('test_vid.mp4');
vid_mat = zeros(950,1690,3,200);
for frame=1:200
img = imread(videoObj,frame);
end

[Stephen23]

This makes no sense:

imread(videoObj,frame)

According to the imread documentation its first input is a filename. A videoReader object is not a filename.

If you want the frames of a video, why not simply follow the examples in the VideoReader documentation?

v = VideoReader('xylophone.mp4');
while hasFrame(v)
    video = readFrame(v);
end

https://www.mathworks.com/help/matlab/ref/videoreader.readframe.html

[noam Y]

I exampled this piece of code from a tutor that taught me Matlab funny he taught me something that doesn't work. thanks for the help

[Stephen23]

@noam Y: do not learn how to use MATLAB from what random people give you (academics can write bad code too). The best place to learn MATLAB code is from the MATLAB documentation:

https://www.mathworks.com/help/matlab/getting-started-with-matlab.html

https://www.mathworks.com/matlabcentral/answers/228557-experts-of-matlab-how-did-you-learn-any-advice-for-beginner-intermediate-users