Discover MakerZone

MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

Learn more

Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

Apply Today

To resolve issues starting MATLAB on Mac OS X 10.10 (Yosemite) visit:

video processing command help

Asked by James on 14 Jul 2011

Can anyone tell me what the following command does?

imgI = double(imread(imgIFile))





No products are associated with this question.

1 Answer

Answer by Jan Simon on 14 Jul 2011
Accepted answer

imglFile : String variable, which contains the name of an image file

imread: Read the image file into a Matlab array

double: convert the array to the double type.

The whole line imports the contents of the image file into a DOUBLE array. "help imread", "help double" would be helpful also.


James on 14 Jul 2011

The double is what I am having difficulty understanding and "help double" does not help explain it either.

Please help

Sean de Wolski on 14 Jul 2011

Your image is probably 8bit unsigned integer - that is, it can be any integer between 0 and 255. So, converting it to double allows it to be any value, up to 16 sigfigs between: 2.2251e-308 and 1.7977e+308

Walter Roberson on 14 Jul 2011

Note: it might perhaps make more sense to use im2double() as that rescales the data as well as changing the data type.

Jan Simon

Contact us