Open Chinese Convert library and utilities

https://github.com/BYVoid/OpenCC

Open Computing Language (OpenCL) specifications V3.0 (header files)

https://github.com/KhronosGroup/OpenCL-Headers/

File format for compression of 3D triangle meshes

https://sourceforge.net/projects/openctm/

High dynamic-range (HDR) image file format

https://github.com/AcademySoftwareFoundation/openexr/

Universal utility for programming FPGA

https://github.com/trabucayre/openFPGALoader

Fast and powerful code search and cross-reference engine

https://opengrok.github.io/OpenGrok/

Open-source implementation of JPEG2000 Part-15

https://github.com/aous72/OpenJPH

Network Time Protocol (NTP) daemon

https://www.openntpd.org/

Implementation of the PGM reliable multicast protocol

https://code.google.com/p/openpgm/

Detects vulnerabilities in running applications

https://github.com/baidu/openrasp

Software to control a multitude of RGB devices

https://openrgb.org

RISC-V SBI bootloader and firmware

https://github.com/riscv-software-src/opensbi

Full-text search engine for Java

https://opensearch.org

Visualization dashboards for OpenSearch

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

SSL and crypto library

http://www.openssl.org/

TLSv1.3 capable SSL and crypto library

https://www.openssl.org/

API and interchange format for editorial timeline information

https://github.com/PixarAnimationStudios/OpenTimelineIO

IETF audio codec

http://opus-codec.org/

Opus playback library

https://opus-codec.org/

Geometric sans-serif typeface intended for display purposes

https://github.com/theleagueof/orbitron

Library and toolset to operate arrays of data

http://code.entropywave.com/projects/orc/

Osinfo database files

https://libosinfo.org/

Tools for managing the osinfo database

https://libosinfo.org/

Vulnerability scanner written in Go which uses the OSV database

https://github.com/google/osv-scanner

Library for loading and enumerating of PKCS#11 modules

http://p11-glue.freedesktop.org/p11-kit.html

Perforce command line client

https://www.perforce.com/products/helix-core

Stub for ancient system-checking module

MeCab library module for Perl5

https://code.google.com/p/mecab/

Perl extension module to use NKF

https://sourceforge.jp/projects/nkf/

Platform support library used by libCEC and binary add-ons for Kodi

https://github.com/Pulse-Eight/platform

DBUS packaging abstraction layer (Qt bindings)

https://www.freedesktop.org/software/PackageKit/

Padring generator for ASICs

https://github.com/donn/padring

Mark Crispin's C-client mail access routines forked from UW

https://github.com/jonabbey/panda-imap

Deprecated pangoX support

http://www.pango.org/

Tools for using Parity v2 Archive files

https://github.com/Parchive/par2cmdline

ParaType font collection for the languages of Russia

https://www.paratype.com/public/

Stores, retrieves, generates, and synchronizes passwords securely

https://www.passwordstore.org/

Utility to modify the dynamic linker

https://github.com/NixOS/patchelf

PC-BSD Shell Library

https://github.com/trueos/pcbsd

Convert X font from PCF to BDF

https://github.com/ganaware/pcf2bdf

Database of all known IDs used in PCI devices

http://pciids.sourceforge.net/

Perl Compatible Regular Expressions library, version 2

https://www.pcre.org/

Smartcard development library

http://alioth.debian.org/projects/pcsclite/

Add outlines to PDF files

https://github.com/eugmes/fntsample

The Public Domain Korn Shell

http://www.cs.mun.ca/~michael/pdksh/

Horde ActiveSync Server Library

https://pear.horde.org