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+--- Thread: Creating a path from a picture (/Thread-Creating-a-path-from-a-picture)
Creating a path from a picture - piscvau - 10-16-2017
Hello
I am using GIMP and INKSCAPE to do cloth personalisation and up-cycling, on LINUX 16.04 Xubuntu.
I have a picture of a stitch garment in 2 colours. (see attachement for a picture with reduced definition)
I would like to get a path from this picture in order to use it in INKSCAPE.
I have tried to use colour selection then selection to path; But the path contains some 35000 nodes and when open in INKSCAPE it never comes back.
I have a high picture definition. I thought about reducing the definition but I am afraid to get "staircases" instead of curves. Do you have any suggestion on howx I could reduce the number of nodes. Is there a modificcation of the image before doing the selection which could help. The "contiguous coulor "selection does not work any better. So any help would be welcomed.
Piscvau
RE: creating a path from a picture - Ofnuts - 10-16-2017
- No attachment in sight, see here for help. Beware of size limitations.
- 35000 nodes isn't that big.
- On the contrary, a small size could help getting less nodes. If necessary, just apply a small blur.
- If the picture has enough contrast, load it in InkScape and use the "Trace bitmap" function to generate the path in Inkscape.
- Doing the paths manually is often easier that you think and often gives better results.
RE: Creating a path from a picture - rich2005 - 10-18-2017
Came up on another forum. The type of image to be processed
http://www.gimpusers.com/system/attachments/714/original/num%C3%A9risattion_collant_1_r%C3%A9duite_pour_envoi.jpg?1508168549
Lots of jagged edges to give lots of nodes. I suggested threshold -> blur -> threshold again to get a smoother edge. Bound to be other ways.
As (3) above, a small image is no disadvantage since a path can be scaled without degradation.
RE: Creating a path from a picture - piscvau - 10-18-2017
(10-18-2017, 07:39 AM)rich2005 Wrote: Came up on another forum. The type of image to be processed
http://www.gimpusers.com/system/attachments/714/original/num%C3%A9risattion_collant_1_r%C3%A9duite_pour_envoi.jpg?1508168549
Lots of jagged edges to give lots of nodes. I suggested threshold -> blur -> threshold again to get a smoother edge. Bound to be other ways.
As (3) above, a small image is no disadvantage since a path can be scaled without degradation.
Thank you very much for both responses.
I am not a gimp professionnal and I am afraid I need some more details.
As I a not a GIMP specialist and moreover I use french version I need to translate your suggestion to make sure I understand it.
I do a "contiguous sélection" using the threshold then I apply the filter blur 'gaussien" on the image then I do a contiguous selection again with threshol.I tried it and it seems to help a lot.
For "security" reasons, my browser does not allow me to uplaod images on this forum!... Supposedly a certificate problem?....
Thanks again for your help
RE: Creating a path from a picture - Ofnuts - 10-18-2017
Scaling to 971x1200, blurring, thresholding, fuzzy select and select-to-path gives a path of 400+ anchors. But the result isn't too accurate, since any technique that involves blurring rounds off the sharp points.
[attachment=818]
However, IMHO, doing it by hand would take 20-30 minutes and give a much better result. I reckon this an be done with 50 anchors or less, giving regular lines and sharps ends where needed.
RE: Creating a path from a picture - Ofnuts - 10-18-2017
Quick 5-minutes shot at it:
[attachment=819]
(picture layer removed to reduce size)
RE: Creating a path from a picture - rich2005 - 10-18-2017
Both of ofnuts examples make the point. The second - hand tracing will give the best result.
This a short video using my original proposal: threshold -> blur -> threshold About 3 minutes, Gimp and Inkscape
https://youtu.be/6ghGIKewT0w
might help
RE: Creating a path from a picture - piscvau - 10-18-2017
(10-18-2017, 10:04 AM)rich2005 Wrote: Both of ofnuts examples make the point. The second - hand tracing will give the best result.
This a short video using my original proposal: threshold -> blur -> threshold About 3 minutes, Gimp and Inkscape
https://youtu.be/6ghGIKewT0w
might help
Hey this is so nice from you. I get a lot of ways to make progress in my use of GIMP. I am going to take the time to go deeply in it. By the way this morning I used your suggestion to do it manually. I did it and it does not take so long. I just had to really understand the 3 modes of paths edition in the tool and I finally discovered how to add a point on the path and drag it to place it exactly where I want.
Thanks again.