I don't understand the different result with convert & crop

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derilzemer
Posts: 21
Joined: 2011-12-12T12:18:16-07:00
Authentication code: 8675308

I don't understand the different result with convert & crop

Post by derilzemer »

Hi @ all,

i'm from Germany and still new at this forum and have to warn anyone about my english. It's terrible, so sorry for that guy's. Anthony Thyssen told me it's better to post here because there are a lot of users who can help me with there experience about crop or convert if i have a problem with that.
I hope this is the right place for this topic. If it isn't, admin please move them to the right place.

Now I have a problem, doesn't know if it is big or a little one :( .
I'm collector of cardgames with technical Data. After buying a game i scan all the cards from the game with a former plate on my scanner with 300 dpi quality, seems like this one http://derilzemer.de/. Next step is to cut all the single cards from the big picture. I'll do this with a script, wich is programmed by my friend (thanks for that Rene). Inside the script we use the following line to cut the single cards from the picture

convert $aktiv_dir/$aktiv_file -crop 4x2\@ +repage -bordercolor black -border 1
-fuzz 70% -trim +repage -quality 100 -resize 250x378
$aktiv_dir/${datei_name}_%d.jpg" >>doit.sh

You can see the result here http://derilzemer.de/file-gut.htm. Most of the cards looks pretty good like Picture 1,4,6,7 and 8 but the pictures 2,3 and 5 doesn't look so fine :(. In addition picture 3 is smaller then the other 7 picture. Is there any possibility to fix this problem or what is failure because the positions inside the former plate are exactly.
The last question. Is there also any possibility to cut the corners from the cards that i doesn't see the black corners? I hope anyone can get me any hints or something to fix or minimize my problem. Thanks a lot for anything.

Regards from Germany
Andy
el_supremo
Posts: 1015
Joined: 2005-03-21T21:16:57-07:00

Re: I don't understand the different result with convert & c

Post by el_supremo »

The problem with the trim is that there are white spots on the scanned image which are too white to be covered by a fuzz of even 70%. You could try an even higher fuzz but that might then start cutting into the images.
You could also try really cleaning the scanning surface to see if you can get rid of the spots so that the scan will be clean enough for trim to work properly.

One way to handle the corners would be to use -fill and -floodfill - see http://www.imagemagick.org/script/comma ... ptions.php

Pete
Sorry, my ISP shutdown all personal webspace so my MagickWand Examples in C is offline.
See my message in this topic for a link to a zip of all the files.
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anthony
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Location: Brisbane, Australia

Re: I don't understand the different result with convert & c

Post by anthony »

You could also try the technqiue shown in...
Trimming 'Noisy' Images
http://www.imagemagick.org/Usage/crop/#trim_noisy
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
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