JBIG

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**JBIG** <tr><th style="white-space: nowrap;">File extension:</th><td>`.jbg, .jbig`</td></tr><tr><th style="white-space: nowrap;">MIME type:</th><td>`image/jbig`</td></tr><tr><th style="white-space: nowrap;">Developed by:</th><td>ISO, IEC, ITU-T</td></tr><tr><th style="white-space: nowrap;">Type of format:</th><td>Image file formats</td></tr><tr><th style="white-space: nowrap;">Extended to:</th><td>JBIG2</td></tr>

This article is about a bi-level image compression scheme. For the designers of this scheme see Joint Bi-level Image Experts Group

JBIG is a lossless image compression standard from the Joint Bi-level Image Experts Group, standardized as ISO/IEC standard 11544 and as ITU-T recommendation T.82. Now that the newer bi-level image compression standard JBIG2 has been released, JBIG is also known as JBIG1. JBIG was designed for compression of binary images, particularly for faxes, but can also be used on other images. In most situations JBIG offers between a 20% and 50% increase in compression efficiency over the Fax Group 4 standard, and in some situations, it offers a 30-fold improvement.

JBIG uses a form of arithmetic coding patented by IBM known as the Q-coder. It bases the probabilities of each bit on the previous bits and the previous lines of the picture. In order to allow compressing and decompressing images in scanning order, it does not reference future bits. JBIG also supports progressive transmission with small (around 5%) overheads.

[edit] External links

JBIG-KIT – a free C implementation of the JBIG encoder and decoder
List of JBIG related resources

Multimedia compression formats
Video compression formats	ISO/IEC	MPEG-1 \| MPEG-2 \| MPEG-4 \| MPEG-4/AVC	ITU-T	H.261 \| H.262 \| H.263 \| H.264	Others	AVS \| Dirac \| Indeo \| MJPEG \| RealVideo \| VC-1 \| Theora \| VP6 \| VP7 \| WMV
Audio compression formats	ISO/IEC MPEG	MPEG-1 Layer III (MP3) \| MPEG-1 Layer II \| AAC \| HE-AAC	ITU-T	G.711 \| G.722 \| G.722.1 \| G.722.2 \| G.723 \| G.723.1 \| G.726 \| G.728 \| G.729 \| G.729.1 \| G.729a	Others	AC3 \| ATRAC \| FLAC \| iLBC \| Monkey's Audio \| Musepack \| RealAudio \| SHN \| Speex \| Vorbis \| WavPack \| WMA
Image compression formats	ISO/IEC/ITU-T	JPEG \| JPEG 2000 \| JPEG-LS \| JBIG \| JBIG2	--	--	Others	BMP \| GIF \| ILBM \| PCX \| PNG \| TGA \| TIFF \| WMP
Media container formats	General	3GP \| ASF \| AVI \| FLV \| Matroska \| MP4 \| MXF \| NUT \| Ogg \| Ogg Media \| QuickTime \| RealMedia	Audio only	AIFF \| AU \| WAV	--	--