Leptonica is a pedagogically-oriented open source site containing software that is broadly useful for image processing and image analysis applications.
Leptonica 是一个面向教学的包含软件的开源站点，此软件对图像处理和图像分析应用十分有用。
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.
特定的操作是：
- 图形操作
- 仿射变换（缩放，旋转，修剪）在任意像素深度上
- 二值和灰度形态学操作，等级排序，卷积
- 种子填充和连通域
- 在尺度和深度上的图像转换
- 像素掩膜，混合，增强，算术操作等
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
辅助操作包括：
- 标准图像格式文件读写
- 操作图像想着数据类型数组的实用工具
- 通用栈、队列、堆和列表的工具；字节序列和数值和字符串数组。
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 generation (levels 1, 2, 3) of images for device-independent output
- PDF generation (levels 1, 2) of images for device-independent output
- Dewarping images of text taken with a camera
- Book-adaptive text recognition
- 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
- Tom Powers has built the Unofficial Leptonica Documentation. It covers all the information in these pages and is more easily navigated. You are encouraged to use it instead.
- 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 high-level view of the source files in the library.
- For a deeper look into specific components of the library, see the web pages linked from the image processing page.
- Uncompleted sets of somewhat detailed usage notes and a lightweight overview have been attempted but are unlikely to be completed anytime in the current millenium.
- The final arbiter is, of course, the source itself.
Source download