JBIG Module

(JBIG Module is an add-on for Document/Medical [version 10 and higher] toolkits)   LEAD offers an optional JBIG module as an add-on to any Document/Medical toolkit.  JBIG defines a method for lossless compression encoding of a bi-level image (two color image). This method can also be used for coding grayscale and color images. LEADTOOLS now completely supports all three types of images, giving you the ability to make full use of this powerful compression technology.  LEADTOOLS also supports the progressive capability of JBIG, allowing you to store and send multiple representations of images at different resolutions without any extra storage overhead.  

To achieve the highest compression ratios available in the JBIG format, LEAD now takes full advantage of all the functional blocks of this robust standard:

• The Adaptive Arithmetic Encoder , which presents the heart of this format, has the ability to predict and hence encode future data symbols based on the data which is being currently encoded.

• The Adaptive Template Block provides real coding gain for images rendered by grayscale with halftoning. This gain ratio approaches 80% in some situations.

• The Typical Prediction Block speeds implementations and provides some coding gain.

• The Resolution Reduction Block is used to get a lower resolution version of an image so that no loss of data is encountered. This is mainly important for bi-level images, to avoid any deletion of thin lines.

• The Deterministic Prediction Block provides good coding gain when saving more than one resolution layer in the same file.

All the free parameters specified by the JBIG standard are applied in LEAD to achieve maximal compression and the highest speed for any saving or loading operation.