RE: hmtx optimization over the Google Fonts collection

Interesting!
Do you have any insight into the fonts that show size increase with hmtx transform applied? It seems counterintuitive that we would ever be in a position to see a size increase since the transform either eliminates some data from the source or leaves it intact. Not sure how/why eliminating chunks of input data would contribute to an increase in overall compressed file size.

Thanks,
Vlad


From: Roderick Sheeter [mailto:rsheeter@google.com]
Sent: Wednesday, January 20, 2016 11:45 AM
To: WebFonts WG
Subject: hmtx optimization over the Google Fonts collection

I did a test run of hmtx optimization over the Google Fonts collection and thought the results might be of interest. A few key results:
·  Of 1754 font files, 80.4% (1411) got smaller, 16.4% (288) had no change, and 3.1% (55) got larger.
·  For fonts with savings, average was 466 bytes or 1.08% of size
o Across all fonts, average was 368 bytes or 0.86% of size
Cheers, Rod S.

Per-font results can be seen in https://docs.google.com/spreadsheets/d/1dgL-il6fIHaHJghlzXz7aM_HEtes9G7Pt7TsnlsxsGc/edit?usp=sharing.