Downloads

Even though Opus is now standardized by the IETF, this Opus implementation will keep improving in the future. Of course, all future versions will still be fully compliant with the Opus IETF specification. See the development page for the latest development information.

Mozilla logo

Development binary builds

In addition to support in Firefox, Mozilla provides binary builds of Opus utilities.

Package	Version	Platform	Download link	Size
opus-tools	0.1.9	Windows	opus-tools-0.1.9-win32.zip	403KiB
opus-tools	0.1.9	Mac OS X	opus-tools-0.1.9-macos.tar.gz	399KiB
Source	opus-tools-0.1.9.tar.gz	376KiB
Opus-tools provides command-line utilities to encode, inspect, and decode .opus files.
opusfile	0.6	Windows	opusfile-0.6-win32.zip	1.5MiB
opusfile	0.6	Source	opusfile-0.6.tar.gz	428KiB
Opusfile provides application developers with a high-level API for decoding and seeking in .opus files. DLLs for the required libraries libogg 1.3.2, libopus 1.1 and openssl, are also included in the binary package.

Source code

Latest stable release

libopus 1.1

Opus 1.1 includes:

new analysis code and tuning that significantly improves encoding quality, especially for variable-bitrate (VBR),
automatic detection of speech or music to decide which encoding mode to use,
surround with good quality at 128 kbps for 5.1 and usable down to 48 kbps, and
speed improvements on all architectures, especially ARM, where decoding uses around 40% less CPU and encoding uses around 30% less CPU.

These improvements are explained in more details in Monty's demo (updated from the 1.1 beta demo).

Source code: opus-1.1.tar.gz

libopus 1.0.3

Opus 1.0.3 includes a backport of the new 1.1 surround API. Aside from that, it includes fixes for a few minor glitches during mode switching, some minor fixed-point fixes, and fixes a regression in the FEC code introduced in 1.0.2.

Source code: opus-1.0.3.tar.gz

Latest development releases

libopus 1.1.1-beta

This is a beta release for the upcoming 1.1.1 version. Compared to 1.1, it mostly includes optimizations for x86, MIPS and ARM.

Source code: opus-1.1.1-beta.tar.gz

opus-tools 0.1.9

This release adds support for 32-bit floating point WAV output and fixes a number of minor issues.

Source code: opus-tools-0.1.9.tar.gz

opusfile 0.6

The opusfile library provides seeking, decode, and playback of Opus streams in the Ogg container (.opus files) including over http(s) on posix and windows systems.

Source code: opusfile-0.6.tar.gz opusfile-0.6.zip

Changes since the v0.5 release:

Fix bugs with comment handling
Fix build for BSD
Fix bugs handling invalid and non-opus streams

Some of these bugs kept basic functionality of the APIs from working at all, so we recommend all users upgrade.