Thank you for the answer. Ok so bitmap tracing is the term I was after:) And I see it exists in other programs so it isn't such a crazy idea after all.
...but like you said, Aammppaa, once the grid is visible and "snap to grid" on, it is a relatively painless task to recreate the shapes for an image of this complexity.
Unfortunately I still have the problem of the integer number pixel sizes. I have used the automatic grid and although it seemed to perfectly match my image, the resulting <svg> has all its values ending with .25 or .75, so the unit on my grid is presumably .25. Which is probably the reason why my SVG is blurred as I reduce the size. I went to the manual grid settings in the manager but the first attempt was a quite scary experience.
I try to solve this but an extra little hint would be welcome. The whole topic does not seem to be over-documented :unsure:
...not sure whether it is useful but I post my <svg> here. My guess is if the coordinate values were integers it would solve my problem. But again, maybe the problem is somewhere else..
<svg width="100%" height="100%" viewBox="0 0 77 27" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" xml:space="preserve" style="fill-rule:evenodd;clip-rule:evenodd;stroke-linejoin:round;stroke-miterlimit:1.41421;"><g><rect x="3.75" y="2.25" width="6.75" height="0.75" style="fill:#fff;"/><rect x="2.25" y="3.75" width="9.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="5.25" width="5.25" height="0.75" style="fill:#fff;"/><rect x="8.25" y="5.25" width="5.25" height="0.75" style="fill:#fff;"/><rect x="0.75" y="6.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="9.75" y="6.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="8.25" width="3.75" height="0.75" style="fill:#fff;"/><rect x="9.75" y="8.25" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="9.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="11.25" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="12.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="14.25" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="15.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="17.25" width="3.75" height="0.75" style="fill:#fff;"/><rect x="9.75" y="17.25" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="18.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="9.75" y="18.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="0.75" y="20.25" width="5.25" height="0.75" style="fill:#fff;"/><rect x="8.25" y="20.25" width="5.25" height="0.75" style="fill:#fff;"/><rect x="2.25" y="21.75" width="9.75" height="0.75" style="fill:#fff;"/><rect x="3.75" y="23.25" width="6.75" height="0.75" style="fill:#fff;"/><rect x="20.25" y="9.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="20.25" y="11.25" width="3.75" height="0.75" style="fill:#fff;"/><rect x="20.25" y="12.75" width="3.75" height="0.75" style="fill:#fff;"/><rect x="20.25" 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