# VOLK

> SIMD abstraction library used by GNU Radio

**Wikidata**: [Q104248149](https://www.wikidata.org/wiki/Q104248149)  
**Source**: https://4ort.xyz/entity/volk

## Summary
VOLK (Vector-Optimized Library of Kernels, libvolk) is a SIMD abstraction software library and GNU Radio sub-project that provides optimized vector kernels for signal-processing workloads. It is free software, distributed and maintained as part of the GNU Radio ecosystem with source code hosted on public repositories such as GitHub.

## Key Facts
- VOLK is a SIMD abstraction library used by GNU Radio and is also described as the "Vector-Optimized Library of Kernels" (alias: libvolk).
- Instance types: software library (start_time: 2015), sub-project, and free software.
- Latest listed stable release in the provided data is version 2.5.2, published 2022-09-04; other stable releases include 2.5.1 (2022-02-12), 2.5.0 (2021-06-05), 2.4.1 (2020-12-17), and 2.0.0 (2019-08-05).
- Official website: https://www.libvolk.org/; development repository (preferred): https://github.com/gnuradio/volk.
- Source code repository alternatives include git://github.com/gnuradio/volk.git, https://www.gnuradio.org/cgit/volk.git/, and git://git.gnuradio.org/volk.git.
- License identifier (as provided): Q27016754.
- User manual / API documentation: https://www.libvolk.org/doxygen/index.html.
- Issue tracker: https://github.com/gnuradio/volk/issues; IRC channel: irc://irc.freenode.net/#volk.
- Packaged in multiple OS distributions: FreeBSD port devel/volk; NetBSD package math/volk; Gentoo package sci-libs/volk; OpenSUSE package volk; MacPorts port volk; SlackBuilds libraries/volk; Guix package variable name volk (example qualifier P348: 2.4.0).
- Copyright holder identifier (as provided): Q48413; copyright_status: copyrighted.

## FAQs
### Q: What does VOLK do?
A: VOLK provides a library of vectorized kernels that abstract SIMD instructions so signal-processing code (notably in GNU Radio) can call optimized implementations across CPU architectures. It supplies performance-focused primitives for vector operations.

### Q: Is VOLK part of GNU Radio?
A: Yes. VOLK is a GNU Radio sub-project and is used by GNU Radio to provide SIMD-optimized kernels for signal processing.

### Q: Where is VOLK's source code hosted?
A: The preferred development repository is https://github.com/gnuradio/volk. Alternate repositories include git://github.com/gnuradio/volk.git and https://www.gnuradio.org/cgit/volk.git/.

### Q: How can I read the VOLK documentation?
A: The user manual and API documentation are available at https://www.libvolk.org/doxygen/index.html.

### Q: On which operating systems is VOLK available?
A: VOLK is packaged for and runs on multiple Unix-like systems, including BSD variants (FreeBSD, NetBSD) and is available via distribution packages (Gentoo, OpenSUSE, MacPorts, Guix, SlackBuilds).

## Why It Matters
VOLK matters because it delivers architecture-aware, SIMD-accelerated primitives that let higher-level signal-processing frameworks—principally GNU Radio—achieve much better performance without embedding per-architecture assembly in application code. By providing a common abstraction layer and a library of optimized kernels, VOLK enables developers to write portable signal-processing code while benefiting from platform-specific CPU vector instructions. Its presence as a maintained GNU Radio sub-project plus packaging across major Unix-like distributions (FreeBSD, NetBSD, Gentoo, OpenSUSE, MacPorts, Guix, SlackBuilds) means it is readily available for deployment and integration in research, prototyping, and production systems. The project hosts its source on public repositories and provides documentation and issue-tracking resources, supporting developer adoption and contributions. For projects that need high-performance vector operations—filters, FFT pre/post-processing, or element-wise arithmetic—VOLK reduces implementation effort and helps achieve consistent, optimized runtime behavior on multiple CPU families.

## Notable For
- Being the SIMD abstraction layer and vector-optimized kernel library used directly by GNU Radio.
- Maintaining multiple stable releases (examples: 2.0.0 through 2.5.2) with public release records and repository tags.
- Wide packaging and distribution across Unix-like ecosystems (FreeBSD, NetBSD, Gentoo, OpenSUSE, MacPorts, Guix, SlackBuilds).
- Public development infrastructure: preferred GitHub repository (https://github.com/gnuradio/volk), issue tracker, and IRC support channel.
- Providing user and developer documentation via an online Doxygen user manual (https://www.libvolk.org/doxygen/index.html).

## Body
### Overview
- VOLK stands for Vector-Optimized Library of Kernels and is also referred to as libvolk.
- It is a SIMD abstraction library used by GNU Radio.
- The project is identified as a software library, a GNU Radio sub-project, and free software.
- The instance start_time for the "software library" classification is listed as 2015.

### Releases and Versions
- Version 2.5.2 — stable version, publication_date: 2022-09-04.
- Version 2.5.1 — stable version, publication_date: 2022-02-12.
- Version 2.5.0 — stable version, publication_date: 2021-06-05.
- Version 2.4.1 — stable version, publication_date: 2020-12-17 (release announcement reference available).
- Version 2.4.0 — stable version, publication_date: 2020-11-22 (release announcement reference available).
- Version 2.3.0 — stable version, publication_date: 2020-05-09.
- Version 2.2.1 — stable version, publication_date: 2020-02-24.
- Version 2.2.0 — stable version, publication_date: 2020-02-16.
- Version 2.1.0 — stable version, publication_date: 2020-02-09.
- Version 2.0.0 — stable version, publication_date: 2019-08-05.

### Source code and development
- Preferred source code repository: https://github.com/gnuradio/volk.
- Other repository URLs: git://github.com/gnuradio/volk.git; https://www.gnuradio.org/cgit/volk.git/; git://git.gnuradio.org/volk.git.
- Issue tracking is handled at https://github.com/gnuradio/volk/issues.
- IRC channel: irc://irc.freenode.net/#volk for community/development discussion.

### Documentation and user resources
- Official website: https://www.libvolk.org/.
- User manual and API documentation: https://www.libvolk.org/doxygen/index.html.

### Packaging and platform support
- FreeBSD port: devel/volk.
- NetBSD package: math/volk.
- Gentoo package: sci-libs/volk.
- OpenSUSE package: volk.
- MacPorts port: volk.
- Guix package variable name: volk (qualifier example P348: 2.4.0).
- SlackBuilds package: libraries/volk.
- Repology project name: volk-simd.
- Operating systems noted include BSD and another OS identifier Q3251801.

### Licensing and legal
- License (identifier provided): Q27016754.
- Copyright holder identifier: Q48413.
- Copyright status listed as: copyrighted.

### Classification and movement
- VOLK is associated with the free software movement.
- Instance classifications include "software library" and "sub-project" and are referenced by project about pages.

(End of entry)

## References

1. [Source](https://www.libvolk.org/about.html)
2. [Release v2.4.1. 2020](https://lists.gnu.org/archive/html/discuss-gnuradio/2020-12/msg00110.html)
3. [Release v2.4.0. 2020](https://lists.gnu.org/archive/html/discuss-gnuradio/2020-11/msg00205.html)
4. [Release 2.0.0. 2019](https://github.com/gnuradio/volk/releases/tag/v2.0.0)
5. [Release 2.1.0. 2020](https://github.com/gnuradio/volk/releases/tag/v2.1.0)
6. [Release 2.2.0. 2020](https://github.com/gnuradio/volk/releases/tag/v2.2.0)
7. [Release 2.2.1. 2020](https://github.com/gnuradio/volk/releases/tag/v2.2.1)
8. [Release 2.3.0. 2020](https://github.com/gnuradio/volk/releases/tag/v2.3.0)
9. [Release 2.5.0. 2021](https://github.com/gnuradio/volk/releases/tag/v2.5.0)
10. [Release 2.5.1. 2022](https://github.com/gnuradio/volk/releases/tag/v2.5.1)
11. [Release 2.5.2. 2022](https://github.com/gnuradio/volk/releases/tag/v2.5.2)
12. [Release 3.0.0. 2023](https://github.com/gnuradio/volk/releases/tag/v3.0.0)
13. [Release 3.1.0. 2023](https://github.com/gnuradio/volk/releases/tag/v3.1.0)
14. [Release 3.1.1. 2024](https://github.com/gnuradio/volk/releases/tag/v3.1.1)
15. [Release 3.1.2. 2024](https://github.com/gnuradio/volk/releases/tag/v3.1.2)
16. [Release 3.2.0. 2025](https://github.com/gnuradio/volk/releases/tag/v3.2.0)
17. [Release 3.3.0. 2026](https://github.com/gnuradio/volk/releases/tag/v3.3.0)
18. [Source](https://guix.gnu.org/en/packages/volk-2.4.0/)