Re: [Offtopic] Club flags: convert PNG to SVG

On 17 May 2017 at 13:14, Antonio Olmo Titos <antonio@w3.org> wrote:
> Regarding the PNG thumbnails of club flags that Andy showed us,
> and the recommendation to use a format that works well at
> any size:
>
> Free & open tools like Inkscape [1] (command "Path / Trace Bitmap")
> and Gimp [2] can detect paths on bitmap images and generate
> a(n approximate) vectorial version.

We have tried these tools with poor results, and it's going to be
better to redraw them from scratch in Inkscape.  Most of the ones we
have were made by complete graphics amateurs on their first attempt
using Paintshop Pro.  I'll see if we can get a volunteer some time in
June.

The flags are supposed to be very simple and usable as icons in dense
sets of results.  My fear with vector is that people will use ornate
crests and decorations which will look unreadable when shown at a
resolution of 30px x 20px.  But that's about the guidelines, not the
tools - SVG is obviously better.   We will also be defining a standard
image size in our hosted system for high quality organisation logos
and shields

- Andy


>
> Also, the command potrace [3] can do that from the command line
> (useful to process a large number of files in batches); either:
>
>   $ convert FILE.png FILE.pbm && potrace -s -o FILE.svg FILE.pbm
>
> or:
>
>   $ cat FILE.png | pngtopnm | potrace -s -o FILE.svg
>
> Caveat: potrace can't handle colours [4]. There are recipes to deal
> with that (eg, extract colours first, run potrace once per colour,
> compose all layers into a single image).
>
>
> [1] https://inkscape.org/en/
> [2] https://www.gimp.org/
> [3] http://potrace.sourceforge.net/
> [4] http://potrace.sourceforge.net/faq.html
>
>
> --
> Antonio Olmo Titos — web developer, W3C
> antonio@w3.org · https://w3.org/People/Antonio
>
>



-- 
Andy Robinson
Managing Director, ReportLab
Wimbletech Zone 2
35 Wimbledon Hill Road
London SW19 7NB, UK
Tel +44-20-8191-7277

Received on Wednesday, 17 May 2017 12:52:27 UTC