determine optimal turd size for potrace

[tarheelcoxn]

$ potrace --help|grep turd

-t, --turdsize - suppress speckles of up to this size (default 2)

Do we need to play with this? This will probably clip dots over the letter "i" if we use it, which would be bad. Perhaps best to leave it alone. Worth experimenting.

[tarheelcoxn]

turd size as high as 3.9 doesn't clip the dots on "i"s... there are smaller speckles that do get picked up with the default that are gone with 3.0, but those speckles seem to come from bleed-through. Perhaps better to clean them up at an earlier step on the process.

[tarheelcoxn]

We ended up not changing this.