how to compare two picture using labview7.1

[cs_teck]

hi,
i have a problem to compare picture. How i can compare the default picture with the capture picture by webcam by using labview7.1. this because i want to find out the different of the object inside the picture.

[chilly_charly]

Subtract one picture from the other (vision>Image processing>operators). If you have a clear object moving over a darker background, it will appear as a clear spot on the resulting image.

CC

[cs_teck]

thx for yr suggestion... i will try it.... thx..

[Nirmal_Sharma]

HI,

use attached vi as sub vi which takes both the images as inputs, compares them and displays status as same or different.

Hope it works.

Nirmal

[cs_teck]

thank for your help.... i will test it

[cs_teck]

I had a curiosity about my example. I had using subtract method to compare my example. When I connect a VI like in figure 1 if the result is equal to zero the led will alight, but when I connect like in figure 2 the led put off in either result. i use all the same type of wire. what wrong in figure 2? why the led no alight when the result of subtraction is equal to zero? pls help me. thx
(attachment figure 2 below)
(attachment figure in the next msg)

[cs_teck]

attachment figure 1

[cs_teck]

this is two image that use in this VI
the distance for bracket1 511.11 and the bracket2 512.61.

[cs_teck]

bracket2

[Nirmal_Sharma]

Hi,
As i have observed by putting a probe on the wire going to indicator "distance", the value is 511.109 but as you have made it round off to 2 decimals, it looks to be as 511.11. So while substracting 511.109 will be in effect & thats why the result is not equal to zero.

Hope it helps.

Thanx & regards,
Nirmal