Holograms2

QUOTE(TobyD @ Feb 22 2008, 06:54 PM) The IMAQ Quantify seems a bit of a loose cannon to me. Its not clear what its comparing the image to. I know have a test image for expected hologram, and my hologram (of laguerre gauss beams). I have scaled them so they are both 512*512 pixels. My program currently takes an image and gives an intensity distribution through the x centroid, and one through the y centroid. Can I plot 2 images on the one graph, ie the x centroid distribution of both the predicted, and actual hologram image, and the same for the y. I need to do this so I can make a direct comparison between the predicted image, and the actual image. Cheers

QUOTE(TobyD @ Feb 14 2008, 05:28 PM) I've worked out what I want to do now. I want to find the 'centre of mass' of the image. using the same prinicple as mechanics, I'll be looking at intensities instead of masses, and sum up the intensities of all pixels to locate a centre point. From that take an x and y sweep to produce an intensity distribution, and from this calculate how round it is by measuring standard deviation. I can't seem to find a function on labview just now to count the number of pixels in the image. I need to be able to know the how many pixels there are and the value of each individual pixels intensity. Hints always welcome. Thanks for the help so far.

QUOTE(crelf @ Feb 13 2008, 02:59 PM) Problem is that I can't seem to find the Imaq fit ellipse function or Imaq fit circle functions. I'm guessing if I have an older version it'll be a tad more complicated to do this.QUOTE(Holograms2 @ Feb 14 2008, 11:40 AM) Problem is that I can't seem to find the Imaq fit ellipse function or Imaq fit circle functions. I'm guessing if I have an older version it'll be a tad more complicated to do this. Just been told that best way would be to plot a Gaussian graph of x components, and then y components and work that way rather than using an ellipse fitting function.

QUOTE(crelf @ Feb 12 2008, 07:19 PM) Tnaks for the advice guys, I've made the image binary and it looks great. Clearly defined edges. I can't seem to find the IMAQ fit ellipse function, I'm guessing I'm using an older Imaq version, someone mentioned there was a problem with this until 6.0.5.

QUOTE(crelf @ Feb 12 2008, 01:17 PM) Should have done a spell check there!!! Image is attached. It is a Laguerre Gauss ring. I want labview to be able to use the number of white image pixels to be able to determine firstly the size of the image and pixels, and then be more specific in measuring how close it is to a circle. Hope this helps a bit.

Hi, first post guys. Hope somebody can help with this! Im currently working on a project that involves computer generated holograms. I am focussing on camera capture of an image, and then calculating how 'round' the image is. The image capture part of the program is running succesfully and displaying an image on my monitor (using an CCD as input). I know want to add a bit on to the program that will allow me to calculate size and roundness of the image. Was thinking of using a histogram to start, is this a good starting point or is there a better way to tackle this? Any help will be much appreciated. Thanks