Reducing bitmapped images before vectorising

Hi,
I have before gotten the advice to filter my images before I vectorise them with Speedline. But which filter should I use to remove some pixels on my bitmapps?

Jonas

If you want to vectorize with Speed~Line, I recommend to convert your images to b&w images. But do not simply click a button and convert e.g. an RGB image to b&w, but convert to Grayscale first. Then play around with FrankLIN in order to find out how to get the best contrast for vectorization.

Speed~Line gets best results from b&w images only - but they don't have to be really b&w, they just have to appear b&w on screen. And furthermore, the zoom factor is important. The higher you zoom, the more edge and border details can be recognized by Speed~Line. (But don't zoom too high, of course.)



Grüße / Greetings / Groetjes / Salutations,
Ulf Dunkel

Yes, I have converted to BW, though greayscale, but I also need to reduce the edges a bit. After I have run Speedline the black parts in the vectorised output, seem to go togehter in some places. It seems like if the black parts have become slightly bigger than in the original. I have gotten the advice to use a filter on the original, that reduces the black parts slightly, before using Speedline. The quesion is, what filter can I use for this?

Jonas

Hi Jonas,

You should use the [b]Median[/b] filter with the [b]right dial[/b] set to somewhere [b]between 51 and 100[/b] to reduce the image in fatness. Between 1 and 50 makes it fatter.
You could play with the left dial: set it to 3 and the effect is small, set it to 10, 100 or more (dependent upon the resolution of the image) and the effect will be dramatic.
The middle dial has little effect in this case.

Happy playing with this incredible filter!

- Paul

Jonas:
If you see some "holes" becoming black in the vectorized stuff, then you will have to toggle the vector path direction for this object.

You should check the outline thickness of the created vector objects, too. I use to select them all and set the vector outline to 0 pt TRANSPARENT.



Grüße / Greetings / Groetjes / Salutations,
Ulf Dunkel

Hi Paul.

I use to set the MEDIAN filter parameters to 5 / 128 / 50 for optimum pixel antialiasing before I start vectorizing with Speed~Line.



Grüße / Greetings / Groetjes / Salutations,
Ulf Dunkel

You could also fatten the image first, so the white spots dissapear (fill up), and then reduce the image with the same amount, so the image has the same fatness as before, but without the white holes.

- Paul