RE: Reporting my findings on Action 123 (http://www.w3.org/Fonts/WG/track/actions/open)

Hi all,

Like we discussed at the last telcon, I ran my experiment on a larger font set (MT web font corpus) - please see the results attached. The average percentage of points that can be predicted (and therefore, eliminated from a compressed font file) inched a bit higher to ~2%. Let's discuss this tomorrow during the telcon.

David, if you could please replace the preliminary results with these on your Google Drive, I'd really appreciate your help!

Thank you,
Vlad


> -----Original Message-----
> From: David Kuettel [mailto:kuettel@google.com]
> Sent: Wednesday, December 04, 2013 4:00 PM
> To: Levantovsky, Vladimir
> Cc: public-webfonts-wg@w3.org
> Subject: Re: Reporting my findings on Action 123
> (http://www.w3.org/Fonts/WG/track/actions/open)
> 
> Thank you Vlad.  I forgot to double check the link.  My apologies.
> Please try this use this link instead:
> 
> Vlad's On-Curve Point Optimization Gains
> https://docs.google.com/a/google.com/spreadsheet/ccc?key=0AvcH1ZzSrGMGd
> EFUMFlEUkFmQ0JCRmFTVGgyNEllRUE&usp=sharing#gid=0
> 
> On Wed, Dec 4, 2013 at 11:57 AM, Levantovsky, Vladimir
> <Vladimir.Levantovsky@monotype.com> wrote:
> > Thank you David, the online spreadsheet is a nice tool, I keep
> forgetting that we can share the data using ways that don't require an
> installed application suite ;-) When I tried to access the file though
> it said that the file doesn't exist (yet?) - can you please check into
> that?
> >
> > Meanwhile, I've made a few changes to my toy project and extended the
> collected dataset to count the exact number of bytes saved if we
> eliminate the coordinates of predictable points. The slightly updated
> spreadsheet is attached, as you can see each eliminated point consumes
> on average 3.12 bytes.
> >
> > Talk to you all soon,
> > Vlad
> >
> >
> >> -----Original Message-----
> >> From: David Kuettel [mailto:kuettel@google.com]
> >> Sent: Wednesday, December 04, 2013 2:26 PM
> >> To: Levantovsky, Vladimir
> >> Cc: public-webfonts-wg@w3.org
> >> Subject: Re: Reporting my findings on Action 123
> >> (http://www.w3.org/Fonts/WG/track/actions/open)
> >>
> >> Fantastic, thank you Vlad!  Looking forward to discussing this in
> the
> >> working group meeting today.  To aid in the discussion, I created an
> >> online spreadsheet along with a chart of the optimization gains.
> >>
> >> Vlad's On-Curve Point Optimization Gains
> >> https://docs.google.com/spreadsheets/d/1PA9ssfAdWh2GKhhgStkw0-
> >> yiiNAeG1zdfZqRzAVWaXM/edit?usp=sharing
> >>
> >> It would be fascinating to see the results of the experiment across
> >> more font collections, esp. to see if any trends/patterns emerged.
> >>
> >> On Tue, Dec 3, 2013 at 2:40 PM, Levantovsky, Vladimir
> >> <Vladimir.Levantovsky@monotype.com> wrote:
> >> > Folks,
> >> >
> >> >
> >> >
> >> > <Rant>
> >> >
> >> > With the Thanksgiving holidays and all travel behind I came back
> at
> >> > the office to a backlog of over 500 emails in my Inbox. Some folks
> >> > clearly don't like holidays and prefer to work overtime - I
> figured
> >> > that it may be a good day to forget about emails and just do
> >> something else instead, like e.g.
> >> > exploring on-curve point optimization. J
> >> >
> >> > </Rant>
> >> >
> >> >
> >> >
> >> > Here are the preliminary results (attached) - so far I ran the
> test
> >> > only on the fonts I have installed on my computer (without
> >> prejudice).
> >> > The numbers reported are:
> >> >
> >> > -          total number of all points for all contours defined in
> a
> >> 'glyf'
> >> > table;
> >> >
> >> > -          number of on-curve points where their coordinates can
> be
> >> > predicted *precisely* by using the coordinates of two adjacent
> >> > off-curve points (and, therefore, the actual coordinates can be
> >> > eliminated from the pre-processed output by simply using one
> >> > reserved bit in 'flags' field to mark the point as "predictable"),
> >> > and
> >> >
> >> > -          percentage of points that can be predicted, per font.
> >> >
> >> >
> >> >
> >> > As you can see, while individual font results vary significantly,
> >> > the average number of all points that can be predicted [with
> >> > respective coordinates eliminated as redundant info] is about
> >> > 1.42%. Considering that point coordinates may use either one- or
> >> > two byte formats - the actual file size saving is likely to be
> >> > somewhat smaller, my guess it would yield the savings of around
> >> > 0.7-1% (this statement has not been evaluated by the FDA!)
> >> >
> >> >
> >> >
> >> > Let's discuss this over email and during the call tomorrow and see
> >> > if there is a desire to do more about it.
> >> >
> >> >
> >> >
> >> > Cheers,
> >> >
> >> > Vlad
> >> >
> >> >