I have a couple of points which IMO are missing from the discussion. # JPEG's missing features & alpha channel capabilities in particular
Arguably, one of the biggest gains from WebP/JPEG-XR support is the ability to send real life photos with an alpha channel. Last time I checked, about 60% of all PNG image traffic (so about ~9% of all Web traffic, according to HTTPArchive.org) is PNGs of color type 6, so 24 bit lossless images with an alpha channel. A large part of these PNGs are real-life images that would've been better represented with a lossy format, but since they require an alpha channel, authors have no choice but to use lossless PNG. (I have no data on *how many* of these PNGs are real life photos, but I hope I'll have some soon). This is a part of Web traffic that would make enormous gains from an alpha-channel capable format, such as WebP or JPEG-XR (Don't know if HEVC-MSP has an alpha channel ATM), yet this is completely left out of the research. I think this point should be addressed. # Implementability in open-source HEVC seemed to be the "winner" of the study, with best scores across most measurements. Yet, I'm not sure an HEVC based format is something Mozilla can implement, since it's most likely to be patent encumbered. If this is not the case, it should be stated loud and clear, and if it is, HEVC should probably be in the research as a point of reference (which other formats should aspire to beat), rather than as a contender. _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
