Re: Try time (decode) and size for null glyf/loca xform vs regular vs woff1

On Thu, May 19, 2016 at 9:00 AM, Roderick Sheeter <rsheeter@google.com>
wrote:

> As requested in https://www.w3.org/Fonts/WG/track/actions/186 I ran a
> variety of compress/decompress scenarios over the Google Fonts collection.
>
> Main findings are:
>
>  * WOFF2 decompression uses less memory than woff, more than brotli
> standalone.
>
>  * WOFF2 decompression was faster than WOFF at min, median, and average
> but has a higher standard deviation and max.
>
>  * Applying brotli (using the "bro" utility;
> https://github.com/google/brotli/blob/master/tools/bro.cc) directly to a
> font (to simulate use via Accept-Encoding: br) resulted in a file that was
> larger than a transformed woff2 but fastest to decompress.
>
>  * WOFF2 decompression is slightly faster when there are no transforms.
> The most significant improvement is lower standard deviation and worst-case
> time.
>
> The brotli codebase is probably the most carefully optimized of the
> implementations I compared. WOFF2 without transform could likely be sped
> up, though some work is hard to dodge without violating the spec. For
> example, "the decoder MUST recalculate the checkSum value for each decoded
> table."
>

But, browsers surely are allowed to skip that if they know the font will
still work equally well.


> Summary and raw results can be seen in
> https://docs.google.com/spreadsheets/d/1_ZYTFaG6_NJy7n_t-RpPDXCAZIKDP_1SXiJQz0o8QMg/edit#gid=367643030
> .
>
> Cheers, Rod S.
>