Audio: STFT Process: Add new SOF module

This module provides analysis and synthesis filters for
frequency domain processing. The used technique is short term
Fourier transform (STFT) and inverse STFT. The FFT length,
hop, and window type are configured with the bytes control
configuration blob.

WIP - the audio quality is not yet good enough

Signed-off-by: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>

Author: singalsu

app/boards/intel_adsp_ace15_mtpm.conf

@@ -15,6 +15,7 @@ CONFIG_COMP_MFCC=y
 CONFIG_COMP_MULTIBAND_DRC=y
 CONFIG_FORMAT_CONVERT_HIFI3=n
 CONFIG_SAMPLE_KEYPHRASE=y
+CONFIG_COMP_STFT_PROCESS=y
 
 # SOF / audio modules / mocks
 # This mock is part of official sof-bin releases because the CI that

app/boards/intel_adsp_ace20_lnl.conf

@@ -11,6 +11,7 @@ CONFIG_COMP_TESTER=m
 CONFIG_COMP_SRC_IPC4_FULL_MATRIX=y
 CONFIG_FORMAT_CONVERT_HIFI3=n
 CONFIG_SAMPLE_KEYPHRASE=y
+CONFIG_COMP_STFT_PROCESS=y
 
 # SOF / infrastructure
 CONFIG_AMS=y

app/boards/intel_adsp_ace30_ptl.conf

@@ -14,6 +14,7 @@ CONFIG_FORMAT_CONVERT_HIFI3=n
 # tests it can't use extra CONFIGs. See #9410, #8722 and #9386
 CONFIG_COMP_GOOGLE_RTC_AUDIO_PROCESSING=m
 CONFIG_GOOGLE_RTC_AUDIO_PROCESSING_MOCK=y
+CONFIG_COMP_STFT_PROCESS=y
 
 # SOF / infrastructure
 CONFIG_KCPS_DYNAMIC_CLOCK_CONTROL=n

app/boards/intel_adsp_ace30_wcl.conf

@@ -14,6 +14,7 @@ CONFIG_FORMAT_CONVERT_HIFI3=n
 # tests it can't use extra CONFIGs. See #9410, #8722 and #9386
 CONFIG_COMP_GOOGLE_RTC_AUDIO_PROCESSING=m
 CONFIG_GOOGLE_RTC_AUDIO_PROCESSING_MOCK=y
+CONFIG_COMP_STFT_PROCESS=y
 
 # SOF / infrastructure
 CONFIG_KCPS_DYNAMIC_CLOCK_CONTROL=n

src/arch/host/configs/library_defconfig

@@ -19,6 +19,7 @@ CONFIG_COMP_SEL=y
 CONFIG_COMP_SOUND_DOSE=y
 CONFIG_COMP_SRC=y
 CONFIG_COMP_SRC_IPC4_FULL_MATRIX=y
+CONFIG_COMP_STFT_PROCESS=y
 CONFIG_COMP_STUBS=y
 CONFIG_COMP_TDFB=y
 CONFIG_COMP_VOLUME=y

src/audio/CMakeLists.txt

@@ -86,6 +86,9 @@ if(NOT CONFIG_COMP_MODULE_SHARED_LIBRARY_BUILD)
 	if(CONFIG_COMP_SRC)
 		add_subdirectory(src)
 	endif()
+	if(CONFIG_COMP_STFT_PROCESS)
+		add_subdirectory(stft_process)
+	endif()
 	if(CONFIG_COMP_TDFB)
 		add_subdirectory(tdfb)
 	endif()

src/audio/Kconfig

@@ -151,6 +151,7 @@ rsource "selector/Kconfig"
 rsource "smart_amp/Kconfig"
 rsource "sound_dose/Kconfig"
 rsource "src/Kconfig"
+rsource "stft_process/Kconfig"
 rsource "tdfb/Kconfig"
 rsource "template/Kconfig"
 rsource "tensorflow/Kconfig"

src/audio/stft_process/CMakeLists.txt

@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: BSD-3-Clause
+
+if(CONFIG_COMP_STFT_PROCESS STREQUAL "m" AND DEFINED CONFIG_LLEXT)
+  add_subdirectory(llext ${PROJECT_BINARY_DIR}/stft_process_llext)
+  add_dependencies(app stft_process)
+else()
+  add_local_sources(sof stft_process.c)
+  add_local_sources(sof stft_process_setup.c)
+  add_local_sources(sof stft_process_common.c)
+  add_local_sources(sof stft_process-generic.c)
+
+  if(CONFIG_IPC_MAJOR_4)
+    add_local_sources(sof stft_process-ipc4.c)
+  endif()
+endif()

src/audio/stft_process/Kconfig

@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: BSD-3-Clause
+
+config COMP_STFT_PROCESS
+	tristate "Template example component"
+	default n
+	select MATH_FFT
+	select MATH_32BIT_FFT
+	select MATH_FFT_MULTI
+	help
+	  Select for stft_process component. Reason for existence
+	  is to provide a minimal component example and use as
+	  placeholder in processing pipelines. As example processing
+	  it swaps or reverses the channels when the switch control
+	  is enabled.

src/audio/stft_process/llext/CMakeLists.txt

@@ -0,0 +1,11 @@
+# Copyright (c) 2025 Intel Corporation.
+# SPDX-License-Identifier: Apache-2.0
+
+sof_llext_build("stft_process_comp"
+	SOURCES	../stft_process.c
+		../stft_process_setup.c
+		../stft_process_common.c
+		../stft_process-generic.c
+		../stft_process-ipc4.c
+	LIB openmodules
+)