Read data from hard disk

Hello, I use Matlab for Image analysis, so I use it for my video experiment. I have my videos on hard disk, so every time I woul like to put it to my Matlab code, I need to first move the video from hard disk to my computer, becouse directly from hard disk it is now working.

How I can do it, is there any special code for it?

Thank you so much.

[Jan]

The question is not clear. Do you mean an external hard disk? What does "it is now (or "not"?) working" mean?

You cannot put a video into the Matlab code. Do you want to import the file data?

[Eliska Paulikova]

Yes the external hard disk.

It means, if is the video in my computer, my code can read it and make a results in 30 seconds. But if I am trying to read it from the hard disk, the code is running and running, but does not give me the results, Just running until I stop it.

[Stephen23]

"How I can do it, is there any special code for it?"

Every MATLAB function that processes data files also accepts absolute/relative filenames. So you can simply define the absolute filenames (i.e. including the path to that external drive). Take a look at:

https://www.mathworks.com/help/matlab/matlab_env/specify-file-names.html

https://www.mathworks.com/help/matlab/ref/fullfile.html

Your question is very vague on detail, but you could use something like

https://www.mathworks.com/help/matlab/ref/uigetdir.html

https://www.mathworks.com/help/matlab/ref/dir.html

to get a list of all files on the externa drive, and then simply loop over them (using absolute filenames, of course).

[Jan]

@Eliska Paulikova: I guess, that the external disk is slow. Then processing a video frame by frame can take a lot of time. Copying the file with copyfile to the internal disk will take some time also, but this can be less stressing, because the data are moved in one block. But actually I assume, the total time for copying and processing is almost equal as for processing the file on the external disk.

You can use the debugger and profiler to find out, what happens inside the code and where the most time is spent.

[Eliska Paulikova]

Ok, thank you so much