Mean of R color values

[vlonjati]

Hi there,

 I am using the read jpg sub vi, I take the image data and after I decimate the array, three vetors each of each corresponding  to R ,G  and B are created.  I calculate the mean value of R in the way shown in my attached program and I find two different values. Can one one explain why that happens?

Thank you

[RavensFan · Accepted solution]

It would be better if you put real data into your input array, make that data the default values for the array, then save the file and upload.

How many elements are in your array?

If you have only 2 elements, then the top mean calculates the mean of those 2.  Your formula node creates a 256 element array that is filled with zeroes.  So only as many elements in your first array will get placed into the new array.  All remaining elements will remain zero, but they will factor into the calculation of the mean.

[vlonjati]

Hi Ravens Fan,

Thank you for your answer, that was a stupid mistake, now that I check the size of R it is 480000 which correspond to the size of 800X600 pixel, i.e. of the picture.