Hello everyone,First of all, im new to labview. Now, this question may have been asked before but im not entirely sure. Ok, so i have an avi video that can be broken down to 50 frames. I used imaq threshold and a for loop to put a threshold in every frame making them black and white. What i want to do is calculate the percentage of area that is highlightened as white. I figured i can do that by calculating the total number of pixels that have an intensity of 1. I know that the black pixels have 0 intensity and i also know the total number of pixels in each frame. I tried using the quantify function but i could not get the desired results. Then i tried using imaq light Meter, but again i could not get the exact number of pixels with intensity of 1, only the mean value and the standar deviation of the pixels. I can probably calculate the area that is intense by using these two values (mean,st.dev.) and simple statistics , i think, but i need more detailed results. Is there a way to get the total number of pixels with intensity of 1 in a black and white frame? sorry if this question has been asked before, i could not find any related one. Sorry for my bad english as well. Awaiting your answers.Thanks a lot.

The problemwith gregoryj's code is that it converts the array of booleans to a number, not a count, The value of that number depends heavily on the position of the Values in the array which are True. Once you have the array of pixels of the black and white image (all values either 1 or 0), just use Array Sum to get the number of ones. Lynn

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calculating pixel intensity in a black and white image

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I forgot that the Boolean to 1:0 conversion uses I16 as its output representation. So if the sum is greater than 32768, the I16 will roll over. I32 can go to 2^31. U64 will probably allow you to sum all the pixels in a movie. Put a conversion bullet following the Boolean to 1:0.

Lynn