Add rnnoise module for background noise reduction

Author: bmatherly

.github/workflows/build-distros.yml

@@ -35,42 +35,43 @@ jobs:
               sed -i 's/^Types: deb/Types: deb deb-src/' /etc/apt/sources.list.d/ubuntu.sources
               DEBIAN_FRONTEND=noninteractive apt-get -qq update
               DEBIAN_FRONTEND=noninteractive apt-get -yqq build-dep mlt
-              DEBIAN_FRONTEND=noninteractive apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev
+              DEBIAN_FRONTEND=noninteractive apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev librnnoise-dev
           - name: ubuntu-24.04
             image: ubuntu:24.04
             setup_script: |
               sed -i 's/^Types: deb/Types: deb deb-src/' /etc/apt/sources.list.d/ubuntu.sources
               DEBIAN_FRONTEND=noninteractive apt-get -qq update
               DEBIAN_FRONTEND=noninteractive apt-get -yqq build-dep mlt
-              DEBIAN_FRONTEND=noninteractive apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev
+              DEBIAN_FRONTEND=noninteractive apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev librnnoise-dev
           - name: ubuntu-22.04
             image: ubuntu:22.04
             setup_script: |
               sed -i '/^#\sdeb-src /s/^#//' "/etc/apt/sources.list"
               DEBIAN_FRONTEND=noninteractive apt-get -qq update
               DEBIAN_FRONTEND=noninteractive apt-get -yqq build-dep mlt
-              DEBIAN_FRONTEND=noninteractive apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev libqt6core5compat6-dev
+              DEBIAN_FRONTEND=noninteractive apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev libqt6core5compat6-dev librnnoise-dev
           - name: debian-unstable
             image: debian:unstable
             setup_script: |
               echo 'deb-src http://deb.debian.org/debian unstable main' >> /etc/apt/sources.list
               apt-get -qq update
               apt-get -yqq build-dep mlt
+              apt-get -yqq install librnnoise-dev
           - name: debian-testing
             image: debian:testing
             setup_script: |
               echo 'deb-src http://deb.debian.org/debian testing main' >> /etc/apt/sources.list
               apt-get -qq update
               apt-get -yqq build-dep mlt
-              apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev
+              apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev librnnoise-dev
           - name: debian-stable
             image: debian:stable
             setup_script: |
               echo 'deb-src http://deb.debian.org/debian stable main\ndeb-src http://deb.debian.org/debian stable-updates main' >> /etc/apt/sources.list
               echo 'deb http://deb.debian.org/debian bookworm-backports main' >> /etc/apt/sources.list
               apt-get -qq update
               apt-get -yqq build-dep mlt
-              apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev
+              apt-get -yqq install cmake qt6-base-dev libqt6svg6-dev librnnoise-dev
           - name: fedora-44
             image: fedora:44
             setup_script: |
@@ -83,7 +84,7 @@ jobs:
                 libtheora-devel libvorbis-devel libvdpau-devel \
                 libsoup-devel liboil-devel python-devel alsa-lib \
                 pulseaudio-libs-devel gcc-c++ cmake ffmpeg-free-devel \
-                movit-devel rubberband-devel vid.stab-devel
+                movit-devel rubberband-devel vid.stab-devel rnnoise-devel
           - name: fedora-38
             image: fedora:38
             setup_script: |
@@ -96,7 +97,7 @@ jobs:
                 libtheora-devel libvorbis-devel libvdpau-devel \
                 libsoup-devel liboil-devel python-devel alsa-lib \
                 pulseaudio-libs-devel gcc-c++ cmake ffmpeg-free-devel \
-                movit-devel rubberband-devel vid.stab-devel
+                movit-devel rubberband-devel vid.stab-devel rnnoise-devel
 
     container:
       image: ${{ matrix.image }}

.github/workflows/build-linux.yml

@@ -38,7 +38,7 @@ jobs:
           sudo sed -i '/^#\sdeb-src /s/^#//' "/etc/apt/sources.list"
           sudo apt-get -qq update
           sudo apt-get -yqq build-dep mlt
-          sudo apt-get -yqq install qt6-base-dev libqt6svg6-dev libqt6core5compat6-dev
+          sudo apt-get -yqq install qt6-base-dev libqt6svg6-dev libqt6core5compat6-dev librnnoise-dev
           sudo apt-get -yqq install cmake ninja-build kwalify
           cmake -D CMAKE_BUILD_TYPE=Debug -D BUILD_TESTING=ON -D SWIG_PYTHON=ON -S . -B build -G Ninja
           cmake --build build

CMakeLists.txt

@@ -40,6 +40,7 @@ option(MOD_QT6 "Enable Qt6 module (GPL)" ON)
 option(MOD_RESAMPLE "Enable Resample module (GPL)" ON)
 option(MOD_RTAUDIO "Enable RtAudio module" ON)
 option(MOD_RUBBERBAND "Enable Rubberband module (GPL)" ON)
+option(MOD_RNNOISE "Enable RNNoise noise-reduction module" ON)
 option(MOD_SDL1 "Enable SDL1 module" OFF)
 option(MOD_SDL2 "Enable SDL2 module" ON)
 option(MOD_SOX "Enable SoX module" ON)
@@ -368,6 +369,11 @@ if(MOD_RUBBERBAND)
   list(APPEND MLT_SUPPORTED_COMPONENTS rubberband)
 endif()
 
+if(MOD_RNNOISE)
+  pkg_check_modules(rnnoise REQUIRED IMPORTED_TARGET rnnoise)
+  list(APPEND MLT_SUPPORTED_COMPONENTS rnnoise)
+endif()
+
 if(MOD_SDL1)
   pkg_check_modules(sdl REQUIRED IMPORTED_TARGET sdl)
   list(APPEND MLT_SUPPORTED_COMPONENTS sdl)
@@ -589,6 +595,7 @@ add_feature_info("Module: Qt6" MOD_QT6 "")
 add_feature_info("Module: Resample" MOD_RESAMPLE "")
 add_feature_info("Module: RtAudio" MOD_RTAUDIO "")
 add_feature_info("Module: Rubberband" MOD_RUBBERBAND "")
+add_feature_info("Module: RNNoise" MOD_RNNOISE "")
 add_feature_info("Module: SDL1" MOD_SDL1 "")
 add_feature_info("Module: SDL2" MOD_SDL2 "")
 add_feature_info("Module: SoX" MOD_SOX "")

src/modules/CMakeLists.txt

@@ -72,6 +72,10 @@ if(MOD_RUBBERBAND)
   add_subdirectory(rubberband)
 endif()
 
+if(MOD_RNNOISE)
+  add_subdirectory(rnnoise)
+endif()
+
 if(MOD_SDL1)
   add_subdirectory(sdl)
 endif()

src/modules/rnnoise/CMakeLists.txt

@@ -0,0 +1,16 @@
+add_library(mltrnnoise MODULE factory.c filter_rnnoise.c link_rnnoise.c)
+
+file(GLOB YML "*.yml")
+add_custom_target(Other_rnnoise_Files SOURCES ${YML})
+
+include(GenerateExportHeader)
+generate_export_header(mltrnnoise)
+
+target_compile_options(mltrnnoise PRIVATE ${MLT_COMPILE_OPTIONS})
+target_include_directories(mltrnnoise PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
+target_link_libraries(mltrnnoise PRIVATE mlt PkgConfig::rnnoise)
+
+set_target_properties(mltrnnoise PROPERTIES LIBRARY_OUTPUT_DIRECTORY "${MLT_MODULE_OUTPUT_DIRECTORY}")
+
+install(TARGETS mltrnnoise LIBRARY DESTINATION ${MLT_INSTALL_MODULE_DIR})
+install(FILES filter_rnnoise.yml link_rnnoise.yml DESTINATION ${MLT_INSTALL_DATA_DIR}/rnnoise)

src/modules/rnnoise/factory.c

@@ -0,0 +1,48 @@
+/*
+ * factory.c -- the factory method interfaces for the rnnoise module
+ * Copyright (C) 2026 Meltytech, LLC
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include "mltrnnoise_export.h"
+#include <framework/mlt.h>
+#include <limits.h>
+#include <string.h>
+
+extern mlt_filter filter_rnnoise_init(mlt_profile profile,
+                                      mlt_service_type type,
+                                      const char *id,
+                                      char *arg);
+extern mlt_link link_rnnoise_init(mlt_profile profile,
+                                  mlt_service_type type,
+                                  const char *id,
+                                  char *arg);
+
+static mlt_properties metadata(mlt_service_type type, const char *id, void *data)
+{
+    char file[PATH_MAX];
+    snprintf(file, PATH_MAX, "%s/rnnoise/%s", mlt_environment("MLT_DATA"), (char *) data);
+    return mlt_properties_parse_yaml(file);
+}
+
+MLTRNNOISE_EXPORT MLT_REPOSITORY
+{
+    MLT_REGISTER(mlt_service_filter_type, "rnnoise", filter_rnnoise_init);
+    MLT_REGISTER(mlt_service_link_type, "rnnoise", link_rnnoise_init);
+    MLT_REGISTER_METADATA(mlt_service_filter_type, "rnnoise", metadata, "filter_rnnoise.yml");
+    MLT_REGISTER_METADATA(mlt_service_link_type, "rnnoise", metadata, "link_rnnoise.yml");
+}