imwrite function for conversion issue?

"If A is a grayscale or RGB color image of data type double or single, then imwrite assumes the dynamic range is [0,1] and automatically scales the data by 255 before writing it to the file as 8-bit values"

>>How matlab do this?

Answer 1

[Walter Roberson]

if isfloat(A)
   temp = uint8(A * 255);
   imwrite(filename, temp);
else
   imwrite(filename, A);
end

[K M Ibrahim Khalilullah]

Thanks