| Better Portable Graphics | |
|---|---|
| Filename extension | .bpg |
| Internet media type | image/bpg, image/x-bpg |
| Magic number | 42 50 47 fb |
| Initial release | 2014 (2014) |
| Latest release | 0.9.8 21 April 2018; 7 years ago (2018-04-21) |
| Type of format | lossy/losslessbitmapimage format |
| Extended from | HEVC |
| Open format? | Yes |
| Website | bellard |
Better Portable Graphics (BPG) is afile format for codingdigital images, which was created by programmerFabrice Bellard in 2014. He has proposed it as a replacement for theJPEG image format as the more compression-efficient alternative in terms of image quality or file size.[1] It is based on the intra-frame encoding of theHigh Efficiency Video Coding (HEVC)video compression standard.[2] Tests on photographic images in July 2014 found that BPG produced smaller files for a given quality than JPEG,JPEG XR andWebP.[3]
The format has been designed to be portable and work in low memory environments, and used in portable handheld andIoT devices, where those properties are particularly important. In 2015 research was working on designing and developing more energy-efficient BPG hardware which could potentially then be integrated in portable devices such as digital cameras.[4][5]
While there is no built-in native support for BPG in any mainstream browsers, websites can still deliver BPG images to all browsers by including aJavaScript library written by Bellard.[1] Others followed Bellard's idea[citation needed] and created theAVIF image format based on theAV1 video codec, which is patent free and therefore got implemented in browsers.
HEVC has several profiles defined for extending its intra-frame encoding to still images at variousbit depths andcolor formats, including "Main Still Picture," "Main 4:4:4 Still Picture," and "Main 4:4:4 16 Still Picture profiles." BPG is a wrapper for the "Main 4:4:4 16 Still Picture" profile up to 14 bits per sample.
BPG'scontainer format is intended to be more suited to a generic image format than the raw bitstream format used in HEVC (which is otherwise ordinarily used within some other wrapper format, such as the.mp4 file format).[2][6]
BPG supports the color formats known as4:4:4,4:2:2, and4:2:0.[2] Support for a separately coded extra channel is also included for analpha channel or the fourth channel of aCMYK image.[2] Metadata support is included forExif,ICC profiles, andXMP.[2]
Color space support is included forYCbCr with ITU-RBT.601,BT.709, andBT.2020 (non-constant luminance) definitions,YCgCo,RGB,CMYK, and grayscale.
Support for HEVC'slossy andlossless data compression is included.
BPG supports animation.[1]
According to Bellard's site[1] BPG may be covered by some of thepatents on HEVC, but any device licensed to support HEVC will also be covered for BPG. Patent issues may prevent JPEG replacement by BPG despite BPG's better technical performance.[6]
Several other image formats have also been proposed as JPEG replacements, including:[3][7]
| Raster | |
|---|---|
| Raw | |
| Vector | |
| Compound | |
| Metadata |
|
