Feature request: add Pass-through and or Jarvis to engraving options

[Roycinger]

When preparing an image for engraving, a passthrough mode would be beneficial.
Reason: VisiCut currently does not have a Jarvis dithering algorithm.
On a different machine (not mine) I had way better results with Jarvis on image engraving than with Floyd-Steinberg.

As Visicut is forcefully using only the given dithering algorithms, an image already dithered with jarvis cannot be engraved properly due to double-dithering.

My proposal would be to implement a true pass-through setting (so that an image can pe prepared with Jarvis prior to importing it into VisiCut) or implementing Jarvis into the preset-list:

Happy to discuss your opinion about this.

Cheers!

[mgmax]

Thanks for your report. Adding Jarvis should be doable for someone slightly familiar Java or C or any similar language. For example, here's the source code of Floyd-Steinberg and it is very similar to how Wikipedia describes it. https://github.com/t-oster/LibLaserCut/blob/master/src/main/java/de/thomas_oster/liblasercut/dithering/FloydSteinberg.java

Regarding "Pass through".

I'm not sure what you mean by "double dithering". A truly black and white input should not be changed by most ditherling algorithms such as Floyd-Steinberg. "Average dithering" is basically the same as no dithering.

In practice, you need to ensure that the input has the same DPI as the lasercutter and is aligned to the pixel grid. Typically this alignment will work if you move it to the top left of the page (or a multiple of 1/dpi inches away from that). Feel free to experiment.