Legacy ImageMagick Discussions Archive

Aha, so the signs are always just two colors: green & red. There's black for some signs, and blue for handicap. Only the black is an issue.

So you're saying floodfill those regions and then discard the rest?

From your images, it will be very hard to detect the boundary of the sign, since the background color in places is very close. You could try -hough-lines. Then find the major lines from the sign and get the intersections. See http://www.imagemagick.org/discourse-server/viewtopic.php?f=4&t=25476 ...

ebr4him@mac ~> convert -version
Version: ImageMagick 6.9.6-2 Q16 x86_64 2016-10-11 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2016 ImageMagick Studio LLC
License: http://www.imagemagick.org/script/license.php
Features: Cipher DPC Modules
Delegates (built-in): bzlib freetype jng jpeg ...

Hi,

I'm want to extract street signs from photographs and deskew them, but I don't know where to begin.

Deskewing I believe is the easy part once the borders are detected?

Here're a few sample images: http://imgur.com/a/uESgY

This one especially seems to be the most challenging: http://imgur ...

Thanks Fred, I tinkered a lot but couldn't find the right combination so ended up just trimming them for now. Thanks anyway!

Version: ImageMagick 6.9.6-2 Q16 x86_64 2016-10-11 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2016 ImageMagick Studio LLC
License: http://www.imagemagick.org/script/license.php
Features: Cipher DPC Modules
Delegates (built-in): bzlib freetype jng jpeg ltdl lzma png tiff xml zlib ...

So basically I want:


convert image.png \
-alpha remove \
-flatten \
-trim \
+repage \
-fuzz 3% \ = $value
-trim \
+repage \
-background $value \
-unsharp 2x0.5+0.7+0 \
-resize 980x980\> \
-bordercolor $value \
-border 44x44 \
-gravity center \
-extent 1024x1024 \
-dither none ...

@GeeMack Great, that helped the resize issue. It was the lack of `+repage` causing issues.

Now how do I set the fuzz as variable so I can use it for bordercolor?

Thanks!

Tried this, but still no luck. Just can't figure the resize command


-fuzz 5% \
-trim \
-unsharp 2x0.5+0.7+0 \
-resize 980x980\> \
-bordercolor white \
-border 44x44 \
-gravity center \
-extent 1024x1024 \
-background white \
-alpha remove \
-dither none \
-interlace none \
-strip ...

I have a couple thousand product images that I need to convert for ecommerce website:

1. Grab the border -fuzz 5% (and save as variable?)
2. Trim -trim (trim before resize to preserve detail?)
3. Resize -resize 980x980
4. Pad with same color border -bordercolor white -border 44x44
5. Center ...

Thanks for the links, however noise reduction and sharpening are least of the problem, I can achieve that easily but its the color 'normalization' that I want.

If you see the border, its different on all sides, light on top, dark on left and normal on bottom and right. Not sure how to 'normalize ...

Oh ok.

6.9.1-6 Q16 x86_64 on Mac

I have this scanned image in low-res:
http://i4ideas.webfactional.com/temp/003.jpg
http://i4ideas.webfactional.com/temp/002.jpg

I need to sharpen the text, smoothen it, clear the noise around it, and for any colored (red title, border especially) elements, ideally I want to convert them to a ...