Linux multimedia framework Pipewire 1.4: MIDI 2 and new audio codecs

The new version of the Linux sound server and multimedia framework Pipewire is arriving in the first Linux distributions following its release by main developer Wim Taymans. For example, Pipewire 1.4 is available in the Arch Linux extra repository and in Fedora Rawhide, which is the precursor to the upcoming Fedora 42. While Pipewire 1.4 missed the deadline for inclusion in Ubuntu 25.04, Debian users can rejoice: the new version of the sound server has arrived in the package sources in time for the upcoming freeze dates for Debian 13 "Trixie". This means that the Debian version expected in the second half of the year will once again be attractive as a Linux system in a studio setup, as Pipewire 1.4 offers welcome innovations, especially for MIDI sequencers and hard disk recording under Linux. This will also have an impact on special distributions for music production such as AV Linux, which draws its packages from the stable branch of Debian.

When the development of Pipewire began around seven years ago, it was primarily intended as a processing framework for video streams. This was because Wayland, with its security models, expected a new framework for recording videos and routing these data streams between applications on the Linux desktop. During implementation in the most efficient C code possible, which, according to Wim Taymans, was achieved by dispensing with the "malloc()" function for memory management, Pipewire quickly became a fully-fledged replacement for Lennart Poettering's Pulse Audio, which was in use at the time. The low latencies when processing audio signals on modern Linux kernels also make Pipewire a replacement for JACK Audio for more professional requirements. The advantage is that with Pipewire, a single sound server can take over the tasks of Pulse Audio as drop-in replacements as well as JACK, thus reducing the initial configuration effort.

Universal MIDI

With version 1.4, Pipewire continues to mature in this role and receives a compatible control API for applications that require JACK and can therefore configure the sound server directly. For MIDI sequencers, Pipewire provides an interface for UMP (Universal MIDI Package) for signal processing, which combines the 1.0 and 2.0 protocols of the MIDI standard. Pipewire can also convert the old MIDI 1.0 to UMP in real time and supply applications with the newer protocol, even if connected MIDI devices only understand the old standard. For the Netjack interface, which also connects JACK applications via TCP/IP, there is now an automatic detection of streams in the network for easier configuration.

For desktop users who only listen to music and audio, Pipewire can offer shorter response times. This is because standard ALSA clients, such as audio players on Linux desktops, now also receive preferential treatment as real-time clients. Pipewire 1.4 no longer differentiates between the client types and now combines their configuration with that of the ALSA plug-ins under the single file "/etc/Pipewire/client.conf" – There is no longer a separate "client-rt.conf".

Listen, listen: New codecs

Among the general audio codecs, there is the new addition of high-resolution DSD (Direct Stream Digital) for particularly audiophile listeners, which works with sampling rates higher than 44.1 kHz. For Bluetooth equipment, there is support for the G.722 codec from Voice over IP systems. With the inclusion of BAP (Basic Audio Profile) broadcast links, Pipewire 1.4 can now route audio signals from one source to almost any number of Bluetooth receivers, which is useful for complex hi-fi setups across multiple rooms and was already provided for in the Bluetooth Low Energy (LE) Audio standards. For hearing aids, Pipewire can offer ASHA codec recording. When working with video streams, Pipewire 1.4 offers the option of embedding filters via FFmepg and applying them directly, for example for conversion tasks.

The release notes of Pipewire 1.4 meticulously list all changes of Pipewire 1.4 on Gitlab. A new processor platform for Pipewire and its libraries has been added with RISC-V, so that Linux systems on the already available developer boards will soon be able to enjoy the benefits of the efficient sound server.

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