Featured operations are

• Rasterop (a.k.a. bitblt)
• Affine transformations (scaling, translation, rotation, shear) on images of arbitrary pixel depth
• Binary and grayscale morphology, rank order, and convolution
• Seedfill and connected components
• Image transformations combining changes in scale and pixel depth
• Pixelwise masking, blending, enhancement, arithmetic ops, etc.

Ancillary operations include

• I/O for standard image formats
• Utilities to handle arrays of image-related data types
• Utilities for generic stacks, queues, heaps and lists; and for byte queues and arrays of numbers and strings

Example applications include

• Octcube-based color quantization, with and without dithering
• Modified median-cut color quantization, with and without dithering
• Skew determination of text images
• Segmentation of page images with mixed text and images
• jbig2 unsupervised classifier
• Border representations of 1 bit/pixel images and raster conversion for SVG
• PostScript wrapping (levels 1, 2) of images for device-independent output
• Rendering text on an image
• Connectivity-preserving thinning and thickening of 1 bit/pixel images
• Line removal from a grayscale sketch
• Search for least-cost paths on binary and grayscale images

Reference documentation for users

• The Leptonica image processing and analysis source code comes with a very weakly restricted copyright license.
• The README gives an overview of installation and usage, with a brief description of the library contents.
• A page of brief notes on version changes.
• A set of somewhat detailed usage notes , still being added to, should introduce you to some of the contents and usage patterns in the library.
• A lightweight overview of the software is also under construction.
• For a deeper look into specific components of the library, see the web pages linked from the image processing page.
• The final arbiter is, of course, the source itself.

Source download

• Click here to download the source. [ update: July 13, 2008]
• See here for further information about the source code.

Contents

1. What is the origin of the name Leptonica?
   
   
2. Image processing at this site [ update: July 13, 2008]
   
   
3. Some issues in software design
   
   
4. A primer on particle physics
   
   
5. A small collection of stellar links
   
   
6. Broadband for Dummies: a primer for safely using the internet with windows [ update: Nov 25, 2007]

Contact: Dan Bloomberg (bloomberg "at" ieee "dot" org) for questions and suggestions