Open Source Libraries
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Browse free open source Libraries and projects below. Use the toggles on the left to filter open source Libraries by OS, license, language, programming language, and project status.
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Dompdf
HTML to PDF converter for PHP
dompdf is an HTML to PDF converter. At its heart, dompdf is (mostly) a CSS 2.1 compliant HTML layout and rendering engine written in PHP. It is a style-driven renderer, it will download and read external stylesheets, inline style tags, and the style attributes of individual HTML elements. It also supports most presentational HTML attributes. PDF rendering is currently provided either by PDFLib or by a bundled version the R&OS CPDF class written by Wayne Munro. (Some important changes have been made to the R&OS class, however). In order to use PDFLib with dompdf, the PDFLib PECL extension is required. Using PDFLib improves performance and reduces the memory requirements of dompdf somewhat, while the R&OS CPDF class, though slightly slower, eliminates any dependencies on external PDF libraries. -
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mPDF
PHP library generating PDF files from UTF-8 encoded HTML
mPDF is a PHP library that generates PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files ‘on-the-fly’ from his website, handling different languages. It is slower than the original scripts e.g. HTML2FPDF and produces larger files when using Unicode fonts, but support for CSS styles etc. and has been much enhanced. Supports almost all languages including RTL (Arabic and Hebrew), and CJK (Chinese-Japanese-Korean). Nested block-level elements (e.g. P, DIV) including margins, borders, padding, line height, background colors, etc. Right-to-left languages are supported, with automatic detection of RTL characters within a document. Transposes tables, lists, text justification, and table cell alignment, as well as a full-text reversal for RTL characters. Automatically detects non-RTL characters and displays these in the original order. -
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OpenPDF
open source Java library for creating and editing PDF files
OpenPDF is a Java library for creating and editing PDF files with a LGPL and MPL open source license. OpenPDF is the LGPL/MPL open source successor of iText, and is based on a fork, of a fork, of iText 4 svn tag. -
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Twemoji
Simple library that provides standard Unicode emoji for all platforms
Twitter’s open source emoji has you covered for all your project's emoji needs. With support for the latest Unicode emoji specification, featuring 3,245 emojis, and all for free. As an open source project, attribution is critical from a legal, practical and motivational perspective in our opinion. The graphics are licensed under the CC-BY 4.0 which has a pretty good guide on best practices for attribution. Although there are two kinds of parsing supported by this utility, we recommend you use DOM parsing, explained below. Each type of parsing accepts a callback to generate an image source or an options object with parsing info. The second kind of parsing is string parsing. This is unrecommended because this method does not sanitize the string or otherwise prevent malicious code from being executed; such sanitization is out of scope. -
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lxml
The lxml XML toolkit for Python
A Python library for efficient XML and HTML processing, known for speed and compatibility. The lxml XML toolkit is a Pythonic binding for the C libraries libxml2 and libxslt. It is unique in that it combines the speed and XML feature completeness of these libraries with the simplicity of a native Python API, mostly compatible but superior to the well-known ElementTree API. The latest release works with all CPython versions from 3.6 to 3.12. See the introduction for more information about the background and goals of the lxml project. -
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JsonCpp
A C++ library for interacting with JSON
JSON is a lightweight data-interchange format. It can represent numbers, strings, ordered sequences of values, and collections of name/value pairs. JsonCpp is a C++ library that allows manipulating JSON values, including serialization and deserialization to and from strings. It can also preserve existing comment in unserialization/serialization steps, making it a convenient format to store user input files. The branch 00.11.zis a new branch, its major version number 00 is to show that it is different from 0.y.z and 1.y.z, the main purpose of this branch is to make a balance between the other two branches. Thus, users can use some new features in this new branch that introduced in 1.y.z, but can hardly applied into 0.y.z. You can download and install JsonCpp using the vcpkg dependency manager. The JsonCpp port in vcpkg is kept up to date by Microsoft team members and community contributors. -
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CoreUI
Open Source UI Kit built on top of Bootstrap 5 and plain JavaScript
CoreUI Admin Panel is not another blend of 3rd parties free components and libraries. It's the only Open Source Bootstrap Admin Dashboard Template built on the enterprise-grade hand-crafted UI Components Library created and backed by professionals. CoreUI and CoreUI PRO are delivered with fully-featured, and ready-to-use admin panel templates for your application. Save thousands of development hours by using ready-made, reusable, and commonly used widgets and UI components. Moreover, CoreUI Bootstrap Admin Template is delivered with a ready-to-use environment, so you don't have to waste time configuring the project. All build scripts and tools are ready to use out of the box. With CoreUI Template you can start a new project in a minute! -
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librdkafka
The Apache Kafka C/C++ library
librdkafka is a C library implementation of the Apache Kafka protocol, providing Producer, Consumer and Admin clients. It was designed with message delivery reliability and high performance in mind, current figures exceed 1 million msgs/second for the producer and 3 million msgs/second for the consumer. librdkafka is licensed under the 2-clause BSD license. KAFKA is a registered trademark of The Apache Software Foundation and has been licensed for use by librdkafka. librdkafka has no affiliation with and is not endorsed by The Apache Software Foundation. SASL (GSSAPI/Kerberos/SSPI, PLAIN, SCRAM, OAUTHBEARER) support. Guaranteed API stability for C & C++ APIs (ABI safety guaranteed for C). Runs on Linux, MacOS X, Windows, Solaris, FreeBSD, AIX, and more. Commercial support is available from Confluent Inc. -
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iText®, a JAVA PDF library
PDF Library for Developers
iText is an open-source PDF library available for Java and .NET (C#). iText allows you to effortlessly generate and manipulate standards-compliant PDF documents with a powerful and feature-rich SDK. With iText, you can create archivable and accessible PDFs, split and merge documents, fill and flatten forms, digitally sign documents, and more. iText add-ons enable additional functionality, such as PDF creation from HTML templates, secure redaction, OCR, and much more. The latest versions of iText build on the success of previous versions and feature an improved document engine, high and low-level programming capabilities, and a more efficient modular structure. iText represents the next level for developers looking to leverage PDF in document workflows. The main project page for iText is now on GitHub, and all the latest releases, code samples, open source add-ons and tools, etc. can be found at https://github.com/itext/. -
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Vanilla.PDF
Cross-platform SDK for creating and modifying PDF documents
Vanilla.PDF is a modern, high-performance, open-source C++17 SDK designed for creating, editing, signing, and analyzing PDF documents across multiple platforms. It requires no external runtime dependencies, making it lightweight and ideal for embedding into desktop applications, servers, or automation pipelines. The SDK offers full cross-platform support including Windows, Linux, macOS, and Android, with builds available for major compilers and architectures. Vanilla.PDF supports advanced PDF features such as adding CMS (PKCS#7) digital signatures, modifying content streams and metadata, and working with encryption and permissions based on standard PDF security models. It includes tools for parsing PDF internals like cross-reference tables and objects, providing fine-grained document analysis capabilities. The project is unit-tested with continuous integration pipelines, supporting sanitizers for enhanced code quality and stability. -
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XLSX
Go (golang) library for reading and writing XLSX files
xlsx is a library to simplify reading and writing the XML format used by recent version of Microsoft Excel in Go programs. Version 3.0.0 introduces some more breaking changes in the API. All methods that can return an `xlsx.File` struct now accept zero, one or many `xlsx.FileOption` functions as their final arguments. These can be used to modify the behavior of the resultant struct, in particular they replace the `…WithRowLimit` variants of those methods with the result of calling `xlsx.RowLimit` and they add the ability to define a custom backing store for the spreadsheet data to be held in whilst processing. The full API docs can be viewed using go’s built in documentation tool. -
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ArduinoJson
JSON library for Arduino and embedded C++. Simple and efficient
ArduinoJson is a C++ JSON library for Arduino and IoT (Internet Of Things). ArduinoJson has a simple and intuitive syntax to handle objects and arrays. ArduinoJson supports both JSON serialization and deserialization. ArduinoJson uses a fixed memory allocation, allowing to work on devices with very little RAM. ArduinoJson can filter large inputs to keep only fields that are relevant to your application, thereby saving a lot of memory. ArduinoJson can parse directly from an input Stream or std::istream. ArduinoJson can produce compact or prettified documents. ArduinoJson works directly with strings stored in program memory. ArduinoJson supports two coding styles, with implicit or explicit casts. ArduinoJson deduplicates strings in the JSON document. When you have several identical keys or values, the JsonDocument only stores one of each. In practice, this feature reduces memory consumption by 20-30%. -
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Lightbox2
The original Lightbox script (v2)
Lightbox is small javascript library used to overlay images on top of the current page. It's a snap to setup and works on all modern browsers. Lightbox2 has been tested successfully in the following browsers, Internet Explorer, Chrome, Safari, Firefox, iOS Safari, iOS Chrome, Android Browser, and Android Chrome. The lightbox-plus-jquery.js file includes jQuery v2.x and supports IE 9+. If you want to support IE 6, 7, and 8, use your own copy of jQuery v1.x with lightbox.js. Lightbox is free to use in both commercial and non-commercial work. Make sure jQuery, which is required by Lightbox, is also loaded. -
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QuestPDF
A library that can help you with generating PDF documents
Quickly design and generate PDF documents with an open-source, modern, and battle-tested C# library. Forget about limitations, feel confident, enjoy your task and efficiently deliver professional products. QuestPDF is a progressive library that can help you with generating PDF documents in your .NET application by offering a friendly, discoverable and predictable C# fluent API. Do you believe that creating a complete invoice document can take less than 200 lines of code? We have prepared for you a step-by-step instruction that shows every detail of this implementation and describes the best patterns and practices. This library is created specifically for designing and arranging document layouts, with full paging support. Alternative solutions, such as HTML-based converters, are not designed for this purpose and therefore are often unpredictable and do not produce desired results. -
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jsoup
Java library for working with real-world HTML
jsoup is a Java library for working with real-world HTML. It provides a very convenient API for fetching URLs and extracting and manipulating data, using the best of HTML5 DOM methods and CSS selectors. jsoup implements the WHATWG HTML5 specification, and parses HTML to the same DOM as modern browsers do. jsoup is designed to deal with all varieties of HTML found in the wild; from pristine and validating, to invalid tag-soup; jsoup will create a sensible parse tree. The parser will make every attempt to create a clean parse from the HTML you provide, regardless of whether the HTML is well-formed or not. You have HTML in a Java String, and you want to parse that HTML to get at its contents, or to make sure it's well formed, or to modify it. The String may have come from user input, a file, or from the web. -
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IRremoteESP8266
Infrared remote library for ESP8266/ESP32
Infrared remote library for ESP8266/ESP32. Send and receive infrared signals with multiple protocols. This library enables you to send and receive infra-red signals on an ESP8266 or an ESP32 using the Arduino framework using common 940nm IR LEDs and common IR receiver modules. e.g. TSOP{17,22,24,36,38,44,48} demodulators etc. Usage of the library has been slightly changed in v2.0. You will need to change your usage to work with v2.0 and beyond. You can read more about the changes required on our Upgrade to v2.0 page. The library has changed from using constants declared as #define to const with the appropriate naming per the C++ style guide. This may potentially cause old programs to not compile. The most likely externally used #defines have been aliased for limited backward compatibility for projects using the old style. Going forward, only the new constant name style will be supported for new protocol additions. -
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ConcatPDF
PDF Concatenation Tool
ConcatPDF is the tool to concatenate PDF files. It can concatenate, extract, encrypt, decrypt, configure PDF files, convert image files to PDF. GUI version and CUI version are both available. iText.NET is iText porting on .NET Framework by J#. This library allows you to generate PDF, (X)HTML, XML, RTF files on Microsoft.NET Framework including ASP.NET. -
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jpeg2pdf
Create PDF from JPEG scans and photos
Cross-platform command-line tool for creation of PDF documents from scans/photos of pages in JPEG (.jpg) format and the lightest weight ANSI C library to put multiple JPEG files into one PDF file. You can add handwritten comments to PDF scans (over original images) with xournal: http://xournal.sourceforge.net/ It supports graphics tablets and saves comments to PDFs as vector data. -
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SimpleXlsxWriter
C++ library for creating XLSX files for MS Excel 2007 and above.
This library represents XLSX files writer for Microsoft Excel 2007 and above. The main feature of this library is that it uses C++ standard file streams. On the one hand it results in almost unnoticeable memory and CPU resources consumption while processing (that may be very useful at saving a large data arrays), but on the other hand it makes unfeasible to edit data that were written. Hence, if using this library the structure of the future report should be known enough. The library is written in C++ with using STL functionality and based on the ZIP library (included), which has a free license: http://www.codeproject.com/Articles/7530/Zip-Utils-clean-elegant-simple-C-Win32 This library is distributed under the terms of the zlib license: http://www.zlib.net/zlib_license.html -
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WFM Reader
WFM file reader and exporter
====== DISCLAIMER ====== Since 2018 WFM reader is out of date. Thanks for using it for several years :) Please use official WFM-file format description (pdf) located at: http://download.tek.com/manual/001137803web_0.pdf ====== DISCLAIMER ====== ====== OBSOLETED DESCRIPTION ====== WFM reader and exporter is the simple application to read WFM file that produced by Tektronix/Rigol oscilloscopes. In the version 2.0: - Recovered the tabbed interface - Added Zooming/Scrolling - Added Legend with Min/Max - Added CSV / Image exporting - Removed 3rd party dependencies for straight recompile Many thanks to Kirk Wolak. https://sourceforge.net/users/kwolak Downloading of previous versions is not recommended. If you want to download the version with full source you can go to "Files" section and select appropritate item to download. ====== OBSOLETED DESCRIPTION ==== -
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JWT
A simple library to work with JSON Web Token and JSON Web Signature
lcobucci/jwt is a framework-agnostic PHP library that allows you to issue, parse, and validate JSON Web Tokens based on the RFC 7519. The package is available on Packagist, you can install it using Composer. A simple library to work with JSON Web Token and JSON Web Signature based on RFC 7519. Once the library has been installed, you are able to issue and parse JWTs. To reduce the chance of having flaky tests on your test suite, the facade supports the usage of a clock object. That allows passing an implementation that always returns the same point in time. -
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adventure
A user-interface library, formerly known as text, for Minecraft
Adventure is a library for server-controllable user interface elements in Minecraft: Java Edition. The Adventure documentation should be used alongside the Javadocs. If you have further questions, feel free to join our Discord. Most users will want to use Adventure as a component of an existing modding platform. The best integrated are our Native Support, but we also support other platforms via adapters. -
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CSSBox
Pure Java HTML / CSS rendering engine
CSSBox is an (X)HTML/CSS rendering engine written in pure Java. Its primary purpose is to provide a complete information about the rendered page suitable for further processing. However, it also allows displaying the rendered document. -
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Sesame
Java RDF Framework
This project is no longer actively maintained. It is succeeded by the Eclipse RDF4J project, which can be found at GitHub and at http://www.rdf4j.org/. Sesame is a de-facto standard framework for processing RDF data. This includes parsing, scalable storage, reasoning and full SPARQL 1.1 query/update support. Sesame offers a fully modular toolkit and an easy-to-use Java API that can be connected to all leading RDF storage solutions. -
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