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Support format bpg in Wikimedia Commons
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BPG (Better Portable Graphics, is a new image format. Its purpose is to replace the JPEG image format when quality or file size is an issue. Its main advantages are:

High compression ratio. Files are much smaller than JPEG for similar quality.
Supported by most Web browsers with a small Javascript decoder (gzipped size: 76 KB).
Based on a subset of the HEVC open video compression standard.
Supports the same chroma formats as JPEG (grayscale, YCbCr 4:2:0, 4:2:2, 4:4:4) to reduce the losses during the conversion. An alpha channel is supported. The RGB, YCgCo and CMYK color spaces are also supported.
Native support of 8 to 14 bits per channel for a higher dynamic range.
Lossless compression is supported.
Various meta data (such as EXIF) can be included.

I think that this format would save maintenance costs, speed, in addition to improving the quality of the images of commons.

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Wilfredor raised the priority of this task from to Medium.
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What tools support BPG? E.g. can you use imagemagick to scale it / convert it to JPEG? (And if so, from which version?) Does GD handle it? VIPS?

What's the browser support for client-side decoding? Does that work on mobile devices? What's the overhead?

On a first glance, this might be more interesting for mobile, as highly lossy compression is where BPG beats JPEG the most.

*Mozilla did a study of various lossy compressed image formats. HEVC (hence BPG) was a clear winner by a wide margin BPG files are actually a little smaller than raw HEVC files because the BPG header is smaller than the corresponding HEVC header.
*BPG natively supports 8 to 14 bits per channel when most other formats use 8 bits (including most of the JPEG implementations and WEBP). It gives a higher dynamic range (which is important for cameras and new displays) and a slightly better compression ratio (because there are less rounding errors in the decoder).
*BPG uses high quality decimation (10 tap Lanczos filter) and interpolation (7 tap Lanczos filter) to handle the chroma samples in 4:2:2 and 4:2:0 formats.
*BPG can be supported in hardware with standard HEVC decoders and encoders (it uses a subset of the Main 4:4:4 16 Still Picture Profile, Level 8.5).

Aklapper lowered the priority of this task from Medium to Lowest.Jan 12 2015, 6:23 PM

Questions in T84943#934372 are still unanswered...

brion added a subscriber: brion.

Being HEVC-based, BPG would presumably be patent-encumbered and thus unusuable for us until some time years in the future unless MPEG-LA and HEVC Advance change their licensing policies. I'm going to go ahead and mark this 'declined' for now.