matrix to 12-bit monochrome jpg

Hello,

I have raw 12-bit monochrome data (stored as an integer) in a file which can be read into matlab.

I have extracted a sample 3x3.

The following produces a file that can not be read by any viewer. ie. XnViewMP, Irfanview and many more.

Even changing BitDepth to 16 does still not work.

x=[1003 647 1011;668 982 677; 977 678 973];

y= uint16(x);

imwrite(y,'example.jpg', 'BitDepth', 12, 'Quality', 100);

Any help would be appreciated.

I can use any format as long as it is 12-bit monochrome.

Thank you Grant

Answer 1

[Sourabh]

Hey @grant

I could reproduce the issue in MATLAB R2023a. Upon further investigation I found that standard image viewers, such as XnViewMP and IrfanView, do not support 12-bit JPEG images due to limited adoption of this format in common software and hardware. Most image viewers widely use 8-bit JPEGs or 16-bit formats like TIFF for higher bit depth.

As a workaround I suggest using the “imread” and “imshow” function to view the 12-bit monochrome JPG image in MATLAB.

Please refer to the following example:

x = [1003 647 1011; 668 982 677; 977 678 973]; 
y = uint16(x); 
imwrite(y, 'example.jpg', 'BitDepth', 12, 'Quality', 100); 

img = imread('example.jpg'); 
imshow(img, []); 

Alternatively, the 12-bit monochrome image can be saved in an uncompressed TIFF format.

Modify the “imwrite” function as follows:

imwrite(y, 'example.tiff', 'Compression', 'none'); 

For more information regarding “imwrite” function, kindly refer the following documentation:

https://www.mathworks.com/help/releases/R2023a/matlab/ref/imwrite.html