IIUC (I am not a color expert so please fill in my knowledge gaps) HDR processed with mDCV and cLLI will produce different colors than HDR processed without. Perhaps that is the breakage concern? If that is the concern, this would only affect PNGs with one/both of those chunks. All other PNGs would be fine. And cICP would be beneficial for WCG and HDR PNGs that don't use those chunks. But like John said, if we can land mDCV and cLLI quickly (they're relatively simple since they just feed the raw values to the client app) perhaps it is fine. So maybe the way we could handle this is give a month for the mDCV/cLLI patch to land before releasing the libpng update? That way if the patch lands in a week we're barely delaying cICP anyway. And if the patch ends up taking a while for some unforeseen reason, we can release without it having made a reasonable tradeoff between benefit and harm for PNGs. On Sat, Jan 4, 2025 at 2:02 AM John Bowler <john.cunningham.bowler@gmail.com> wrote: > On Fri, Jan 3, 2025 at 5:12 PM Chris Lilley <chris@w3.org> wrote: > >> I agree with John that delaying cLLI and mDCV would be unfortunate and >> produce breakage. >> > > I've just submitted pull request > https://github.com/pnggroup/libpng/pull/635. If Cosmin accepts that this > is moot because it provides full support for the two chunks. > > John Bowler >
Received on Saturday, 4 January 2025 12:15:56 UTC