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Implementing JBIG Features

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.

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. You can use the ReadLoadResolutions method to examine which sizes are available in a file. You can then use the Resolution property to specify which size to load. When saving a file, you can use the SetResolutions method to set resolutions for the next save operation.

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 To implement progressive loading of a JBIG image, use the CodecsLoadOptions:T:Leadtools.Codecs.CodecsLoadOptions class to set the number of passes/resolutions to load. Progressive loading will be implemented as follows LoadImage:E:Leadtools.Codecs.RasterCodecs.LoadImage
  • If the image contains more than one resolution and LoadImage:E:Leadtools.Codecs.RasterCodecs.LoadImage The data that gets passed to the callback and/or inserted into the image will be padded to the remaining width Passes:P:Leadtools.Codecs.CodecsLoadOptions.Passes To unlock JBIG support, the Unlock:M:Leadtools.RasterSupport.Unlock(Leadtools.RasterSupportType,System.String) The Unlock:M:Leadtools.RasterSupport.Unlock(Leadtools.RasterSupportType,System.String) For more information about required files, refer to Files To Be Included With Your Application:T:Leadtools.Topics.FilesToBeIncludedWithYourApplication

    JBIG support is available only with the Document/Medical:T:Leadtools.Topics.RasterProDocMed% toolkits.