Version 0.4.0 (Jun 14, 2024)


  • finish RTCP & XR support (gh-14, gh-674)

    • handle all reports from RFC 3550 and some XR reports

    • implement 2-way RTCP reports exchange

    • route packets to sessions according to SSRC and CNAME

    • support RTT calculation based on RTCP XR packets

    • improve packet validation

    • support packet padding

    • support RTCP multicast

  • support latency tuning and clock drift compensation on sender instead of receiver (gh-675)

  • implement backend for WAV files without external dependencies, useful in contrained environments (gh-576)

  • implement libsndfile backend for audio files (gh-246)


  • rework latency configuration, introduce concept of latency tuner, available on both sender and receiver (by default enabled on receiver and disabled on sender)

    • replace roc_clock_sync_backend with roc_latency_tuner_backend

    • replace roc_clock_sync_profile with roc_latency_tuner_profile

  • rework metrics API (gh-681)

    • replace roc_session_metrics with roc_connection_metrics

    • rework roc_sender_metrics and roc_receiver_metrics; connection metrics are now available on both sender and receiver

    • functions for querying metrics (roc_sender_query(), roc_receiver_query(), roc_sender_encoder_query(), roc_receiver_decoder_query()) are reworked and simplified

    • niq_latency is removed from API

  • support 2-way control packet exchange in codecs API (roc_sender_encoder and roc_receiver_decoder)

    • rename roc_sender_encoder_push() to roc_sender_encoder_push_frame()

    • rename roc_sender_encoder_pop() to roc_sender_encoder_pop_packet()

    • add roc_sender_encoder_push_feedback_packet()

    • rename roc_receiver_decoder_push() to roc_receiver_decoder_push_packet()

    • rename roc_receiver_decoder_pop() to roc_receiver_decoder_pop_frame()

    • add roc_receiver_decoder_pop_feedback_packet()

  • rename roc_version_get() to roc_version_load()

Command-line tools

  • rework latency configuration:

    • rename --sess-latency to --target-latency

    • replace --clock-backend with --latency-backend

    • replace --clock-profile with --latency-profile

  • rename options:

    • --packet-length to --packet-len

    • --packet-limit to --max-packet-size

    • --frame-length to --frame-len

    • --frame-limit to --max-frame-size

  • support floats for sizes and durations (gh-654)

  • support NO_COLOR and FORCE_COLOR environment variables (gh-564)

Bug fixes

  • fix routing of FEC packets in encoder/decoder API (roc_sender_encoder and roc_receiver_decoder)

  • fix segfault when roc-send input device omitted (gh-728)

  • fix work when no_playback_timeout is lower than target_latency (gh-657)

  • fix “unexpected already cancelled task” panic

  • properly handle allocation errors in HeapArena


  • add Ubuntu 24.04 to CI (gh-634)

  • add macOS 14 (arm64) to CI

  • add OpenWrt with uCLibc and musl (MIPS32) to CI

  • fix build on Debian GNU/Hurd

  • improve handling of unknown unix-like platforms in scons


  • new optional dependency: libsndfile, used in CLI tools (gh-246)


  • support frame of different format in different parts of pipeline (gh-547)

  • continue work on configurable encoding (gh-608)

  • continue work on surround sound support (gh-86)

  • start work on configurable limits (gh-610)

  • improvements and refactoring in roc_core

Build system

  • fix --build-3rdparty on macOS 14

  • fix static library on macOS (libroc.a); ensure that all object files have unique names

  • fix macos linker warnings about -lc++

  • fix build with macports installed; don’t implicitly use brew if pkg-config is not from brew

  • fix openssl search

  • workaround for brew + pkg-config + openssl error on macOS

  • fix building old pulseaudio on clang 17


  • improve tests for capture timestamps (CTS)

  • improve RTCP tests (in roc_rtcp, roc_pipeline, and public_api)

  • improve pipeline tests

  • add tests for metrics


  • document audio backends

  • document sponsored work

Version 0.3.0 (Nov 22, 2023)


  • support lower latencies, up to 7ms in our tests

  • add new clock synchronization profile (responsive) suitable for lower latencies

  • major improvements in C API (network-less API, metrics API, many small improvements)

  • more flexible packet encoding configuration (currently available only via C API):

    • more channel layouts: mono, stereo, multitrack (up to 1024 channels)

    • custom smaple rate

  • improve scaling precision of speex resampler

  • implement new speexdec resampler, combining SpeexDSP for base rate conversion and decimation for clock drift compensation, which has better scaling precision than speex and is very cheap when base rates are equal


  • implement new encoder / decoder API (roc_sender_encoder and roc_receiver_decoder), which is network-less version of sender / receiver API (encoder produces packets, decoder consumes packets, and user is responsible for delivering packets)

  • implement initial metrics API:

    • add roc_session_metrics, roc_receiver_metrics, and roc_sender_metrics structs (currently they support niq_latency and e2e_latency)

    • add roc_sender_query(), roc_receiver_query(), roc_sender_encoder_query(), roc_receiver_decoder_query() to query metrics

  • improvements in slot support:

    • support deleting slots on fly using roc_sender_unlink() and roc_receiver_unlink()

    • refine error handling rules: if error happens during slot configuration, slot is marked broken and excluded from pipeline, but needs manual removal by user

    • slot identifiers are now arbitrary long long numbers (not necessary continuous)

  • simplify receiver configuration:

    • replace max_latency_overrun + max_latency_underrun with one parameter latency_tolerance

    • rename broken_playback_timeout to choppy_playback_timeout

    • remove breakage_detection_window (automatically derive it from choppy_playback_timeout)

  • simplify interface configuration:

    • introduce roc_interface_config struct, which holds all per-interface options

    • replace roc_sender_set_outgoing_address() and roc_sender_set_reuseaddr() with roc_sender_configure() (which uses roc_interface_config)

    • replace roc_receiver_set_multicast_group() and roc_receiver_set_reuseaddr() with roc_receiver_configure() (which uses roc_interface_config)

  • rework encoding configuration:

    • rename roc_frame_encoding enum to roc_format (in API, “encoding” now means format + rate + channels, which is now true for both frame encoding and packet encoding)

    • add roc_media_encoding struct which defines format + rate + channels

    • use roc_media_encoding instead of frame_encoding + frame_sample_rate + frame_channels in roc_sender_config and roc_receiver_config

    • rename roc_channel_set to roc_channel_layout

    • remove packet_sample_rate and packet_channels (these parameters are now derived from packet_encoding)

    • if packet_encoding is not set, automatically choose one that matches frame_encoding (among built-in and registered packet encodings)

  • support channel layouts:



    • ROC_CHANNEL_LAYOUT_MULTITRACK - up to 1024 channels without special meaning

  • support packet encodings:



  • support registering custom packet encodings using roc_context_register_encoding()

  • add roc_clock_sync_backend parameter, with two values:

    • ROC_CLOCK_SYNC_BACKEND_DISABLE - do not adjust receiver clock

    • ROC_CLOCK_SYNC_BACKEND_NIQ - adjust receiver clock based on network incoming queue size (current behavior)

  • add roc_clock_sync_profile parameter with three values:

    • ROC_CLOCK_SYNC_PROFILE_GRADUAL - adjust clock smoothly (old behavior, good for high jitter and high latency)

    • ROC_CLOCK_SYNC_PROFILE_RESPONSIVE - adjust clock smoothly (good for low jitter and low latency) ROC_CLOCK_SYNC_PROFILE_DEFAULT - select profile automatically based on target_latency




Command-line tools

  • replace --min-latency + --max-latency with --latency-tolerance

  • remove --no-resampling (use --clock-backend=disable instead)

  • add --clock-backend and --clock-profile

  • rename --np-timeout to --no-play-timeout

  • replace --bp-timeout + --bp-window with --choppy-play-timeout

  • rename --beeping to --beep

  • rename roc-conv tool to roc-copy

  • list supported endpoint schemes in --print-supported

Bug fixes

  • fix NTP 2036 year problem

  • fix latency reported in logs


  • change default packet length from 7ms to 2.5ms

  • get rid of hard-coded frame length in pipeline components (now they work with any requested frame length), which allows to handle latencies lower than default frame length

  • support capture timestamps (CTS) in packets and frames (based on RTCP + NTP) and forward them through the pipeline, needed for end-to-end latency calculation

  • start work on calculation of end-to-end latency (overall delay from sender to receiver, including I/O and network)

  • start work for automatic mapping between different channel layouts and orders (including mono, stereo, surround, and multitrack layouts)

  • start work for reporting and forwarding error codes through the pipeline

  • implement fast lock-free PRNG

  • optimize task processing: process pipeline tasks in-place when they’re scheduled from I/O thread, to avoid unnecessary delays

  • improve memory protection:

    • always employ memory poisoning in arenas and pools

    • implement buffer overflow protection using canary guards in arenas and pools

    • implement ownership checks in arenas and pools

  • module roc_peer renamed to roc_node (because it now has non-peer nodes)

Build system

  • add --compiler-launcher scons option (may be used for ccache)

  • correctly handle --enable-debug-3rdparty for all dependencies


  • improve C API doxygen comments

  • fix pulseaudio C API examples

  • numerous improvements and updates in sphinx documentation

Version 0.2.6 (Nov 05, 2023)


  • build debian packages on debian:bullseye

  • in debian packages, statically link all dependencies except libc, libasound, libpulse

  • ensure that packages are installable on debian:oldstable, debian:stable, ubuntu:20.04, ubuntu:22.04, ubuntu:latest

Version 0.2.5 (Jul 28, 2023)

Bug fixes

  • fix byte order conversion

Build system

  • fix compiler type detection when compiler is specified via CC or CXX variable

  • export symbols of dependencies built by --build-3rdparty when building static library (libroc.a), to avoid linker errors when using it

Version 0.2.4 (May 13, 2023)


  • always set file and line in roc_log_message

Command-line tools

  • support PulseAudio sources in roc-send

  • support --io-latency option in roc-send

Bug fixes

  • fix potential race

  • fix byte order detection on Android

  • do not write to log from shared library destructor

  • stop using user-provided log handler after entering shared library destructor


  • improve logging

  • refactor scons scripts

Build system

  • fix --build-3rdparty=sox when sndio is installed

  • fix --build-3rdparty=google-benchmark when there is python3, but no python in PATH

  • fix OpenSSL platform detection in --build-3rdparty=openssl when not cross-compiling

  • set Android API level to 21

  • add --macos-platform and --macos-arch scons options

  • by default, set --macos-platform to current OS, to avoid linker warnings about incompatible macOS deployment targets

  • support building macOS universal binaries by providing multiple values for --macos-arch

  • propagate Android platform, macOS platform, and macOS architectures to --build--3rdparty

  • unexport all symbols except roc_* from and libroc.a on Linux, and libroc.dylib on macOS

  • resolve pkg-config absolute path


  • minor updates

Version 0.2.3 (Mar 09, 2023)


  • add roc_receiver_set_reuseaddr and roc_sender_set_reuseaddr

Command-line tools

  • add --reuseaddr to roc-recv and roc-send

Bug fixes

  • fix formatting of endpoint URI with zero port

  • fix usage of multicast with RTCP in roc-recv

Build system

  • add new dependency OpenSSL

  • fix work with SCons 4.5

  • exclude sox and libpulse from .pc file for libroc


  • add debian packages and publish them on github

  • add rpm packages spec


  • minor updates

Version 0.2.2 (Feb 27, 2023)


  • rename roc_get_version to roc_version_get

Bug fixes

  • fix crash in roc_log_set_handler when argument is NULL

Build system

  • fix build on recent Android NDK

  • install .pc file to <libdir>/pkgconfig instead of PKG_CONFIG_PATH

  • add support for DESTDIR

  • strip symbols in release build


  • minor updates

Version 0.2.1 (Dec 26, 2022)

Build system

  • install to /usr by default (except macOS)


  • minor updates

Version 0.2.0 (Dec 19, 2022)


  • support multicast

  • support broadcast

  • support speex resampler and make it default

  • support slots (connect sender to multiple receivers and vice versa)

  • initial support for RTCP


  • return error codes from roc_context_open, roc_receiver_open, roc_sender_open

  • introduce roc_endpoint to identify endpoints using URI

  • rename roc_fec_code to roc_fec_encoding

  • add roc_resampler_backend

  • add roc_clock_source

  • add roc_version and friends

Command-line tools

  • use URIs to identify audio devices and endpoints

  • add --backup option to roc-recv

  • replace --frame-size with --frame-length and --frame-limit

  • remove --resampler-interp and --resampler-window

Bug fixes

  • fix race in PRNG

  • fix race in mutex and semaphore on macOS

  • fix potential deadlock in network code


  • Linux / aarch64 build fixes

  • Android build fixes

  • macOS build fixes

  • FreeBSD build fixes

  • support generic Unix target

  • continuous integration for more Linux distros

  • continuous integration for Android

  • testing on Raspberry Pi 4


  • add roc_peer module

  • add roc_ctl module

  • support for asynchronous tasks in roc_pipeline, roc_netio, roc_ctl

  • lock-free task queues

  • optimizations to avoid unnecessary context switches

  • improvements in memory pools

  • improvements in logger

  • self-profiling

  • start work on SDP support

  • preparations for RTSP support

  • rework project structure

  • lots of small improvements

Build system

  • add --enable-static and --disable-shared

  • add --disable-soversion option

  • compatibility with recent SCons versions

  • compatibility with different Python versions

  • improve toolchain detection

  • generate .pc file for pkg-config

  • fix build with recent PulseAudio

  • fix build with recent libunwind

  • fixes for building third-parties


  • add benchmarks

  • lots of small updates


  • document Android bulding and testing

  • lots of small updates

Version 0.1.5 (Apr 05, 2020)


  • fix building on Manjaro Linux

  • fix building on Yocto Linux

  • add openSUSE to continuous integration and user cookbook

  • drop Xcode 7.3 from continuous integration, add Xcode 11.3

Build system

  • correctly handle arguments in environment variables like CXX/CC/LD/etc (for Yocto Linux)

  • correctly handle spaces in environment variables (for Yocto Linux)

  • fix environment overrides checks

  • fix building of the host tools when cross-compiling

  • fix warnings on Clang 11

  • fix sphinx invocation

  • explicitly disable Orc when building PulseAudio using –build-3rdparty

  • explicitly enable -pthread or -lpthread for libsndfile (for Manjaro Linux)

  • user CMake instead of autotools when building libuv for Android using --build-3rdparty

  • switch to libuv 1.35.0 by default in --build-3rdparty

  • check for unknown names in --build-3rdparty

Version 0.1.4 (Feb 06, 2020)


  • fix logging

Build system

  • make /usr/local prefix default everywhere except Linux

  • make default compiler consistent with CXX var


  • fix SoX download URL (again)

  • fix CPU count calculation


  • update PulseAudio version numbers in “User cookbook”

  • update CONTRIBUTING and “Coding guidelines”

  • update maintainers and contributors list

Version 0.1.3 (Oct 21, 2019)

Command-line tools

  • add --list-drivers option

  • add git commit hash to version info


  • print backtrace on Linux and macOS using libunwind instead of glibc backtrace module

  • print backtrace on Android using bionic backtrace module

  • colored logging

Build system

  • add libunwind optional dependency (enabled by default)

  • add ragel required dependency

  • rename “uv” to “libuv” in --build-3rdparty

  • don’t hide symbols in debug builds

  • strip symbols in release builds

  • fix building on recent Python versions

  • fix SoX download URL

  • fix PulseAudio version parsing

  • automatically apply memfd patch when building PulseAudio

  • automatically fix libasound includes when building PulseAudio

Version 0.1.2 (Aug 14, 2019)

Bug fixes

  • fix handling of inconsistent port protocols / FEC schemes

  • fix IPv6 support

  • fix incorrect usage of SO_REUSEADDR

  • fix panic on bind error

  • fix race in port removing code

  • fix packet flushing mechanism

  • fix backtrace printing on release builds


  • fix building on musl libc

  • continuous integration for Alpine Linux


  • rework audio codecs interfaces (preparations for Opus and read-aheads support)

  • minor refactoring in FEC support

  • improve logging

Build system

  • allow to configure installation directories

  • auto-detect system library directory and PulseAudio module directory


  • extend “Forward Erasure Correction codes” page

  • add new pages: “Usage”, “Publications”, “Licensing”, “Contacts”, “Authors”

  • replace “Guidelines” page with “Contribution Guidelines”, “Coding guidelines”, and “Version control”

Version 0.1.1 (Jun 18, 2019)

Bug fixes

  • fix memory corruption in OpenFEC / LDPC-Staircase (fix available in our fork)

  • fix false positives in stream breakage detection


  • start working on Android port; Roc PulseAudio modules are now available in Termux unstable repo

  • continuous integration for Android / arm64 (minimal build)

  • docker image for aarch64-linux-android toolchain

Build system

  • fix multiple build issues on macOS

  • fix multiple build issues with cross-compilation and Android build

  • fix issues with building third-parties

  • fix issues with compilation db generation

  • set library soname/install_name and install proper symlinks

  • improve configuration options

  • improve system type detection and system tools search

  • improve scripts portability

  • better handling of build environment variables


  • fix resampler AWGN tests

  • add travis job to run tests under valgrind

Version 0.1.0 (May 28, 2019)


  • streaming CD-quality audio using RTP (PCM 16-bit stereo)

  • maintaining pre-configured target latency

  • restoring lost packets using FECFRAME with Reed-Solomon and LDPC-Staircase FEC schemes

  • converting between the sender and receiver clock domains using resampler

  • converting between the network and input/output sample rates

  • configurable resampler profiles for different CPU and quality requirements

  • mixing simultaneous streams from multiple senders on the receiver

  • binding receiver to multiple ports with different protocols

  • interleaving packets to increase the chances of successful loss recovery

  • detecting and restarting broken streams


  • initial version of transport API (roc_sender, roc_receiver)

Command-line tools

  • initial version of command-line tools (roc-send, roc-recv, roc-conv)


  • GNU/Linux support

  • macOS support

  • continuous integration for Ubuntu, Debian, Fedora, CentOS, Arch Linux, macOS

  • continuous integration for x86_64, ARMv6, ARMv7, ARMv8

  • toolchain docker images for arm-bcm2708hardfp-linux-gnueabi, arm-linux-gnueabihf, aarch64-linux-gnu

  • testing on Raspberry Pi 3 Model B, Raspberry Pi Zero W, Orange Pi Lite 2