This is Tim's captcha proposal from 2014. But without the gradiant added. It "Reduce['s] k, increase wob scale, increase rr fuzz..to more reliably bend the baseline". See git change df4806c64c48c2cd2
Note, this uses the DejaVuSans font, instead of the FreeMonoBoldOblique.ttf that Wikipedia currently uses
View other captcha tests: Current captcha | Tim's proposal | Tim's captcha without gradiant | Current captcha with OCR rejection | Using negative kerning and less harriness [Bawolff's proposal] | Negative kerning and harriness
Tesseract (off the shelf. No special training) success on this set is 12 (out of 200) or 6.0 %