Scanned papers not "lining up" with subject (calage or layout problem)

Added by Alex Alex about 3 years ago

When grading my latest batch of papers, AMC is not finding the correct layout, as can be seen in the attached screenshots.

It is unlikely, but possible, that I updated the documents between now and when I printed the subject.

What is surprising to me (and what I am trying to understand) is why I am actually able to make the boxes line up perfectly to the scanned papers in GIMP. In the attached screenshot, there are actually three layouts visible: The scanned paper (slightly blurry), the subject pdf (sharp boxes), and the automated annotations (the thick circles and boxes). The pdf and scanned boxes are almost perfectly lined up (you can't even tell them apart in the second screenshot), but the annotations are clearly wrong.

To obtain these images in GIMP, I used the transform tool to place each of the four corner dots of the subject pdf on top of the scanned ones (the scanned papers are a bit rotated and smaller compared to the pdf). I assume that this is what AMC also does? In this case, shouldn't the layout work?

(I am scripting AMC (following the guide in the wiki), so I don't have access to the GUI to check the layout. )


Replies (3)

RE: Scanned papers not "lining up" with subject (calage or layout problem) - Added by Alex Alex about 3 years ago

Some more info:

I tried some more things. The attached screenshot shows the cr/page-2-1.jpg file on the left. The purple layout is shown, and it is not lining up. On the right of the same image is the subject pdf file. The bottom left dot for both files is also shown. Everything lines up perfectly between the scanned paper and the subject, but not the purple layout. Here the scanned file was first hand aligned with the subject in GIMP, before giving it to AMC (so it's not a problem with the AMC preprocessing of the image).

Looking at the whole page-2-1.jpg file shows that the layout is correct at the top of the page then gradually gets shifted lower and lower.

Additionally, I am using the following layout options in the tex subject file:

\AMCinterBquest=0.3cm
\geometry{hmargin=2cm,headheight=1cm,headsep=.3cm,footskip=1cm,top=3cm,bottom=2.5cm}

Screenshot_3.png (62.9 kB)

RE: Scanned papers not "lining up" with subject (calage or layout problem) - Added by Alex Alex about 3 years ago

So after more investigation, I could confirm that this is a bug (will make a report, but I'm adding the answer here in case someone finds it through a search). I have created an issue here: https://project.auto-multiple-choice.net/issues/765. This seems to be the same issue as this one : https://project.auto-multiple-choice.net/boards/2/topics/6946, which unfortunately did not have a solution except to not print a subject with the "wrong" values for headheight. Since I already received papers to grade with this subject, it does not help me.

Does anyone know how to get check the layout without using the GUI?

RE: Scanned papers not "lining up" with subject (calage or layout problem) - Added by Alex Alex almost 3 years ago

Update: To answer my own question on how to "save" my batch of already filled-in papers, I simply removed the headheight=1cm option from the latex subject and updated the documents. This had the effect to produce the exact same subject pdf except on the first page, this time with the correct layout (except on the first page). I then graded the first page without AMC.

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