Convert an 8 bit image to 12 bit

I am trying to convert an image from 8bit to 12 bit. I understand 8 bit can go from 0-256 while 12 can go from 0-4095 i believe. Basically i am using the bit value for analysis purpose so using a 12 bit image makes more sense for me. However I don't have a lot of experience with image processing. Can i simply multiply the 8 bit values by a fraction of 256 or something similar? If anyone has any experience doing this can provide some feedback. I have read about going from 12 bit to 8 bit but it is hard to find information on going the other way.

Answer 1

[Chunru]

I = imread("peppers.png");          % 8-bit image
whos

  Name          Size                Bytes  Class    Attributes

  I           384x512x3            589824  uint8              
  cmdout        1x33                   66  char               

I1 = double(I)/256;      % 8->12bit
imwrite(I1, 'test.jpg', 'BitDepth', 12);   % JPEG supports 12 bits

I2 = imread('test.jpg');
class(I2)

ans = 'uint16'

I2 = rescale(I2);           % rescale
class(I2)

ans = 'double'

imshow(I2)

[Amir Cawich]

Thank you so much. It works