Problem about writing las file and pointCloud attributes

Hello,

I got the following problems about LAS file reading and writing:

(1) I read a LAS file that contains uint8 RGB information as a pointCloud object (calls it ptCloud1), actually MATLAB read the RGB info correctly as an uint8 RGB attribute. However, after I wrote this pointCloud object as a LAS file, the color values are not correct anymore: when I read the output LAS file as a new pointCloud object (calls it ptCloud2), I found that the color values are 0 or 1 in the RGB attribute of ptCloud2, even though the data type is uint8.

Do you have any solution to correctly write the same RGB values into a new LAS file as the original one?

(2) Then, I tried to replace the color info in ptCloud2 using double RGB values between 0 and 1 by transforming from ptCloud1 using the following codes, and then write out the double RGB info with values between 0 and 1, but I failed:

ptCloud2.Color = []; % Tried to clear the RGB info, but could not excute

ptCloud2.Color = double(ptCloud1.Color)/255;

Do you have any idea to clear the color attribute in a pointCloud object and then replace with new values with a different data type? or is there a method to change the type of Color attribute from uint8 to double?

(3) I created a new pointCloud object as ptCloud3 and then replaced the RGB values using the color info of ptCloud1 by using the following codes:

ptCloud3 = ptCloud2;

ptCloud3.Color = ptCloud1.Color;

Then, I found that the Color info in ptCloud2 has also been changed, which has the same value with ptCloud1.Color and ptCloud3.Color.

But I did not excute ptCloud2.Color = ptCloud1.Color;

So could some one please tell my what happened and WHY?

I used the MATLAB version of R2022a, in which the functions of lasFileWriter and writePointCloud for writing las files were first introduced.

Thank you very much for any help.