[PNG] Meeting topics - Dec 8th, 2025

Hello everyone,

This is our first meeting after TPAC 2025.
The PNG WG calendar is currently missing its entry & the Zoom link. CL and
I will try to get that back.

Some discussion topics:

   - The PNG WG was rechartered. It extended our timeline for further work
   into 4th Edition & 5th Edition. Please rejoin the WG under the new charter.
   - There are some action items from the TPAC meeting. We should discuss
   which ones we can tackle and assign the work to members.
   - Are there industry standard tests specifically for icons and logos?
   (Peak) Signal to noise ratio has always been a standard but isn't great
   because lossy compression takes advantage of our perception. There are
   alternatives, like SSIM. But will those work well for icons and logos, or
   do those favor photos?
      - For a lossy PNG to make sense, we need to first assess how well
      existing formats handle icons and logos. And we need to make sure we're
      assessing correctly.
      - Do we have a set of test images for this? Public domain icons,
      perhaps? I believe US road & safety iconography might work.
   - At the end (so non-implementers may choose to leave) Cosmin would like
   to talk about libpng planning.