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BPG Image format

News

• (Apr 21 2018) Release 0.9.8 is available.

Introduction

• High compression ratio. Files are much smaller than JPEG forsimilar quality.
• Supported by most Web browsers with a small Javascript decoder(gzipped size: 56 KB).
• Based on a subset of theHEVCopen 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 alphachannel is supported. The RGB, YCgCo and CMYK color spaces are alsosupported.
• Native support of 8 to 14 bits per channel for a higher dynamic range.
• Lossless compression is supported.
• Various metadata (suchasEXIF, ICC profile, XMP)can be included.
• Animation support.

Download

libbpg-0.9.8.tar.gz

Binary distribution for Windows (64 bit only):bpg-0.9.8-win64.zip

UnofficialGithub mirror.

For Mac users, the BPG utilities are available in thelibbpgHomebrew formula.

Performance

• Mozilla did astudy 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 otherformats use 8 bits (including most of the JPEG implementationsandWEBP). It gives ahigher dynamic range (which is important for cameras and new displays)and a slightly better compression ratio (because there are lessrounding errors in the decoder).
• BPG uses high quality decimation (10 tap Lanczos filter) andinterpolation (7 tap Lanczos filter) to handle the chroma samples in4:2:2 and 4:2:0 formats.
• BPG can be supported in hardware with standard HEVC decoders andencoders (it uses a subset of the Main 4:4:4 16 Still Picture Profile,Level 8.5).

Demo

• Visual comparison between BPG (x265 encoder), JPEG (mozjpegencoder), JP2K and WebP
• Lena 512x512 image, visual comparison with JPEG
• Wikipedia photos
• Images with alpha channel
• Test images using different color spaces and bit depth
• Test animations

Technical information

Licensing

• The BPG decoding library uses a modified version of FFmpegreleased under the LGPL version 2.1 as HEVC decoder. The BPG decodinglibrary excluding the FFmpeg code is released under the BSD license.
• The BPG encoder as a whole is released under the GPL version 2license. The BPG encoder sources excluding x265 are released under theBSDlicense. Thex265library is released under the GPL version 2 license. The optionalJCTVC HEVC referenceencoder is released under the BSD license.
• Some of the HEVC algorithms may be protected by patents in somecountries (read theFFmpegPatent Mini-FAQ for more information). Most devices already includeor will include hardware HEVC support, so we suggest to use it ifpatents are an issue.