BW Image Overlay On Another One

[Mic_Scale]

Hello,

I posses Labview 7.1 with the vision module.

I'm building an application of Image Data Acquisition, where I'm trying to overlay a PASS/FAIL black & white image (white dots tell where there's an error) on another black & white video image.

I would like to turn the white dots of the PASS/FAIL image into red, in order to be able to see them on the video picture. Moreover, I would like the black color of the overlay to be transparent when overlaying on the video image, so that it won't block the video image.

Currently both of the images are represented as 2D arrays, of 16 bit. I guess some work with color planes and/or color representation of 32bit will be needed.... I'm new at working with the Vision module, could anyone help or maybe send an example please ?

[Lorne H.]

Mic_Scale,

Attached is a simple VI which will convert your overlay 2D 16bit Array into a 1D array of points which can be fed into the "IMAQ Overlay Points.vi".  The IMAQ Overlay VI will convert the 1D array of points to an overlay of whatever color you choose.

The attached VI takes your 2D array.  Compares each element in the array to 0 and adds an element to the new 1D array each time the element in the 2D array is greater than 0.

Before you can use the "IMAQ Overlay Points.vi" you will need to convert you black and white image to an IMAQ Image by using the "IMAQ ArraytoImage.vi".

All of this should accomplish the task you want.

Good Luck,
Lorne Hengst
Application Engineer
National Instruments