match pattern 180 degrees

[DMJeff]

Hi all,

Thank you all for your assistance as this project has moved along, it has been very helpful.

I can now read a file of images from the disk, locate a simple reflection, and using that, center my measurements and calculations.

My client now wants to change the setup, so that I have a semi-circular reflection of many points.  That's okay, I used the Vision Assistant to capture another 'master' image to match.

And that works okay for one instance.

However, I also want to match the same image, in another location within the same frame, but rotated 180 degrees.

I'm sure I can capture a second 'master' image, and run the matching routine again, but that is a relatively slow routine compared to the rest of my calculations.

I was trying to figure out if I could instruct the 'IMAQ Match Pattern 4 VI' to find the pattern, in this opposing orientation.

In the Parameters input cluster, I added a second member in the 'Angle Ranges' array, indicating that the routine should look at an angle range of 175 to 185, as well as the original 0,0.

When I ran the routine, it didn't find the second location (I did indicate that the routine should find 2 instances).

I pulled down the selection list in the Advance Options input cluster, and there were a lot of options that didn't make sense to me, so I just left that at the default.

I'm hoping this is fairly straight forward, without having to rerun the images twice...

Thank you for any assistance you can provide.

Jeff

[KateB]

1. Change from Shift-Invariant to Rotation-Invariant.

2. Try lower minimum score.

3. Try wider range of an engle setting.

[DMJeff]

Hi KateB,

Thank you for the suggestions.

This VI doesn't take the Shift-Invariant or Rotation-Invariant as an input, so I'm not sure where that might be set.

I tried a lower score, but there are a number of similar areas in the image that I want to filter out, so if I set it too low I get a lot of uwanted matches.

I did have some success using the Vision Assistant, and opening up the angle settings to +- 10 degrees (-10 to +10 and 170 to 190).

Thanks for the suggestion,

Jeff

[Klemen]

Hello,

the shift invariant or rotation invariant modes are specified during the template learning stage (imaq learn pattern 4). If your input angle array is empty the mode is only shift invariant.

Best regards,
K