Optical Registration error message

I’m using APro2 on an iMac. I scanned a 12-field drawing with visible peg holes, 72 dpi on an HP scanner/printer with an updated driver.

In the “Import Images” dialogue window under “Vectorization”, I dbl-clk on “Greys” to get the Vectorization Parameters window. I check the “Optical Registration” box, set the Opt-Reg to 72 DPI. The peg side & field chart are both correct. When I go to vectorize I get an error message: “Optical Registration failed”. I’ve tried different settings but nothing works.

Can anyone help me figure out why? Thank you.

Do you have a lot of dirt or writing around your 3 peg holes? Especially the center one?
- Are you scanning standard 12 field paper or smaller paper?
The optical registration searches for a center peg hole about 8 inches from the leading edge (left side) of the paper. If your center peg holes is too far from 8 inches it might not find it.
- Are the peg holes showing on your drawing within a 1 inch strip at the bottom of the page? The optical registration cuts a 1 inch strip at the bottom of the image, then searches in that area for the center peg hole, then finds the side peg holes for the rotation adjustment. Once all this is done it transpose these offset and angle to the rest of the image.

If you post the image we can look if it’s in the right standard.

Wow Steve, thank you for the detailed explanation. Where did you find this info??

Looks like my problem is that my scanner is smaller than the 12 field paper. But I can probably tape down a pegbar outside the glass area and register the drawings that way.

Thanks again!

I can get that info because I work at Toon Boom.

You can still do the optical registration with a smaller scanner but you will loose the top part of your 12 field area at the top. If your animation is done in consequence it could work. I know that in some schools they don’t want to use full standard 12 field paper so they adjust in consequence.

Using the physical peg bar outside the scan area is another solution like you said although a bit less precise because the peg bar and paper positioning, hole tears, etc come into play.

The center peg hole on the 12 field paper I’m using is about 6 inches from the edge and I think it’s standard. Does the hole really need to appear 8 inches from the leading edge? Is there a minimum distance it can be?

Another thing is that my scanner glass is 11 inches wide, not wide enough to show the entire width of a 12-field sheet of paper. Could that be messing things up?..

I don’t know the exact range but it’s around 1 inch on either side I think. So maybe from 7 to 9 inches should work. Maybe you can scan the paper a little to one side.

Thanks Steve. That didn’t work for me.

Does the scanner have to be 13 inches wide, wide enough to scan the entire width of the 12-field paper? The one I’ve got is 11 inches wide.

Did you rotate your image to have the peg holes at the bottom of the image? This is important. The setting bottom,top, right and left is for the output of the vectorization. It’s not where to find the peg holes. The peg holes always have to be at the bottom even if you animated on top pegs. Once it’s vectorized and you put top it would reposition your image the good way (peg at the top).

I used a small scanner 8.5 x 11.5 (Canon LIDE 60) with 12 field paper and it works fine for the optical registration.
I put an example of a drawing that I scanned at 150 dpi. You can try it out and see if you have the same issues.

Steve, thanks for the image. Yes, that’s the same size scanner, same size paper and peg hole location I’m using.

Could you please post a screen shot of your Vectorization Parameters window showing all your settings? That would be a huge help.

By the way, when you say the setting bottom, top, right and left is for “the output of the vectorization”, what does that mean?

Thanks for all your time.

Like I said the Optical registration always searches to find peg holes at the bottom of the source image. Then it sends these adjustement values to the vectorization. While it vectorizes it has the choice to rotate the output vector image. The rotate amount can be 0,90,180 or 270 (bottom, right, top or left).

If it still doesn’t work can you post your image that you are trying to import and vectorize.

By the way the image I put is normally a bit too dirty as a final image but I just grabbed any image I had at hand.

Uploaded with ImageShack.us

Thank you Steve. I used all your settings but when I returned to the “Scan Drawings” window and hit OK I still got:

- Optical registration failed.
- Could not vectorize scanned images while creating layer Drawing

"Drawing" is the name of the existing layer I told it to add to. It gives the same message if I Create a Layer. Here’s a screenshot of one of the drawings and also the error message:


I think your peg holes are too light. Try putting a darker color behind the holes so that they are more black.

Did you try to import and vectorize my image? Did it work?

Aha!! The peg holes were indeed too light!

Your drawing optically-registered just fine, and when I rescanned mine with a black strip behind the peg holes it scanned and registered without error messages.

I also found that 150 dpi is the only dpi setting that works. I tried 72 and 200 and got the same errors.

Thank you!