mozilla/pdf.js — pull request #4466 by p01 (2014-03-14 14:36:42+00:00)
Title: Faster 1 bpp image drawing

Moving up the end condition and using Uint32Array view of the destination array where possible gives about ~36% speed improvement on 33M pixels B&W images ( typical B&W scanned document ), going from ~1180ms down to ~753ms.