- From: John Bowler <john.cunningham.bowler@gmail.com>
- Date: Tue, 22 Apr 2025 11:15:27 -0700
- To: "Portable Network Graphics (PNG) Working Group" <public-png@w3.org>
- Cc: "Chris Blume (ProgramMax)" <programmax@gmail.com>
>That would not have been okay, to be clear: https://www.w3.org/policies/process/#meeting-recording However the following section pretty much says that _discussions_ have to be minuted. Normally this is done either by a dedicated trained recorder or by an audio recording which is minuted after the meeting by the nominated recorder. As @programmax observes: >During the meetings, I have been taking minutes + running the meetings. You're right that they're very summarized. It is difficult to juggle it all quickly enough to keep the pacing. Yes. I'd describe the task as impossible. Oregon has pretty much come down to using audio recordings for all government meetings because there is rarely money for a trained recorder; I've only seen them in courts. Even Grand Jury testimony is now recorded by audio. But I don't see a real problem; given your situation surely the meeting members would consent to you recording the meeting solely for the minutes? The group could decide whether to destroy the recording after you had produced minutes or to archive it solely for the purpose of resolving any dispute over the content of the minutes. >Is there something you're hoping to learn that wasn't sufficiently covered by the summary? Indeed there is. It's a separate topic and it comes down to the "Generic image data" item. I assume this refers to maps other than "gain maps" such as "height" maps (most commonly people seem to call these "bump" maps although that term is technically more general). APNG already defines a basic approach for storing additional "maps" in a single PNG file using sequence numbers and storing interlaced control information and IDAT compressed data. The use of APNG for storing PCB layouts where each layer of the layout is a separate APNG frame has been raised elsewhere as part of the APNG implementation discussion. The context is for a "plug in" for KiCAD. Previously @svgeeus had raised the idea of generalising the APNG fcTL and fdAT chunks: https://sourceforge.net/p/png-mng/mailman/message/36044127/ The links in that message can be found by deleting the spurious ">" at the end of the URIs (they will show 'page not found' on first click.) The second link in particular refers, in passing, to "layers" but that's an established requirement (the KiCAD plug-in) and, despite the "can of worms" comment seems to be very simple to implement. There are many issues coming together here and they come together as a generalization of the base APNG format (fdAT with a control chunk) to allow arbitrary 2D maps to be stored. But was this mentioned, discussed, raised, deferred? I'm particularly mystified by the two comments: >Enough doubt about complication vs. simplicity and if that is worth any potential benefit >Possibly revisit based on gain maps What does that mean? Certainly gain maps are a whole lot more complicated than height maps and way, way more complicated than layers or sprites in general. The solution to gain maps necessarily involves a new control chunk which can change the IHDR format fields (colour type and bit depth) and, yes, that change is necessary for bump maps most of the time but bump maps (in the sense of height maps) _are already implemented in PNG_. Height maps are interchangeable as PNG files between different 3D rendering programs; the only issue is how to package the height map with the texture map. What is more adding all the other maps commonly used is pretty much a no-brainer because FOSS software already does it and has done it for years. There's a massive list of such maps. I just looked at the UI from a modeller for a texture designed for use with NVidia Iray - I counted 45 different maps I can set. But this isn't complexity at the PNG level, all of those maps are _already_ described in PNG. They just can't be packaged together! John Bowler <jbowler@acm.org>
Received on Tuesday, 22 April 2025 18:15:42 UTC