Meeting minutes - Aug 8th, 2022

Attached is a PDF of the meeting minutes from Aug 8th, 2022.

Executive summary:

   - PNG encoders and decoders are already strongly motivated to behave
   well (displaying what they can, for example). Any error handling wording we
   add to the spec to encourage this would not provide additional motivation.
   Instead, if we want to encourage good error handling behavior we should
   provide sample images to validate error cases.
   - We should be firm on PNG encoders to not write out-of-bounds palette
   indices. For decoders, we can provide a note which mentions that different
   decoders behave differently and there are images in the wild which abuse
   this.
   - Further research is needed to make a decision about the unused
   trailing bytes in a compression stream.
   - The PNG spec wording should change away from claiming unused high bits
   of bKGD and tRNS values "are zero". The wording should instead be along the
   lines of "should be zero". Additionally, the spec should mention that these
   bits are ignored. This change clarifies that this is not an error condition.
   - There are several issues with the definitions section. At the moment,
   it seems like trimming the definition section will act as a common solution
   to these issues.

The next meeting will be Aug 22nd, 2022 from 11am-noon Eastern US time.

A future email will list topics for that meeting.