TL;DRzr - A simple algorithmic summarizer
Copyright (c) 2013, Saurav Mohapatra All rights reserved.
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TL;DRzr (Pronounced as tee-el-dee-rai-zer) is a simple algorithmic summary generator written in java. It's deployed as a heroku app accessible at https://tldrzr.herokuapp.com
I wrote this as a weekend hack / fun project. Feel free to use the code as you please. Would love a mention or a line back at mohaps AT gmail DOT com if you find this useful. My twitter is @mohaps and my blog is at http://mohaps.com
I'm currently working on the v2 of this project with better extraction, modularization and updates to use Java 8 features.
Join the Hacker News Discussion About TL;DRzr : https://news.ycombinator.com/item?id=5523538
Hacker News Post about the source code release : https://news.ycombinator.com/item?id=5535827
Prerequisites (for Build)
JDK 1.6+ Apache Maven 2.x+
Running the application locally
First build with:
$mvn clean install
Then run it with:
$java -cp target/classes:target/dependency/* com.mohaps.tldr.Main
How does it work?
TL;DRzr uses an algorithm derived from Classifier4J. I used the basic algo from Classifier4j, optimized it and added some refinements.
The basic algorithm for summarization is like this. It first tokenizes the text into words and then calculates the top N most frequent words (discarding stop words and single occurence words). It then scans the sentences and gets the first N sentences which feature any or all of the most frequent words. The sentences are sorted based on first occurence in original text and concatenated to create the summary. The user has control over how long the generated summary should be in terms of sentence count.
For implementation details a good starting point is the Summarizer class.
TL;DRzr is written in Java and uses Jsoup for html text scraping, ROME for RSS Feed parsing (which depends on JDOM). The parsing of sentences and word tokenization uses OpenNLP. It uses the Porter2 stemmer algorithm from here to process the tokens emitted by the tokenizer. The new summarize any url feature uses BoilerPipe
TL;DRzr is a weekend project/quick hack demo created by Saurav Mohapatra. I wrote this as a fun weekend hack after reading about the Summly acquisition by Yahoo!. I had drunk too many Red Bulls and sleep was not too forthcoming. :) I always wished to try out Heroku and after a couple of hours of googling + coding, I put this together.
The algorithm is a keyword density based one. As this is my current hobby project, I shall work on improving the algorithm. I plan on opensourcing this codebase on github..