audio: ffmpeg_dec: add MP3 and AAC-LC encoder mode (libshine, vo-aacenc) and capture topologies

src/audio/ffmpeg_dec/CMakeLists.txt

@@ -24,6 +24,9 @@ else()
   else()
     add_local_sources(sof ffmpeg_dec-ffmpeg.c)
     add_local_sources(sof ffmpeg_dec-convert.c)
+    if(CONFIG_FFMPEG_DEC_ENCODE_MODE)
+      add_local_sources(sof ffmpeg_dec-encode.c)
+    endif()
     # Scalar soft-float for the SOF glue that touches float. core-isa.h reports
     # XCHAL_HAVE_FP=1 so LLVM would lower the FLT/FLTP -> Q1.31 sample conversion
     # in ffmpeg_dec_emit_frame() to hardware FP0 ops (lsi/mul.s/trunc.s), which
@@ -39,6 +42,9 @@ else()
         ${CMAKE_CURRENT_SOURCE_DIR}/ffmpeg_dec.c
         ${CMAKE_CURRENT_SOURCE_DIR}/ffmpeg_dec-ffmpeg.c
         ${CMAKE_CURRENT_SOURCE_DIR}/ffmpeg_dec-convert.c)
+    if(CONFIG_FFMPEG_DEC_ENCODE_MODE)
+      list(APPEND _ffmpeg_dec_sources ${CMAKE_CURRENT_SOURCE_DIR}/ffmpeg_dec-encode.c)
+    endif()
     if(CMAKE_C_COMPILER_ID MATCHES "Clang")
         set_source_files_properties(
             ${_ffmpeg_dec_sources}
@@ -86,6 +92,21 @@ else()
       # calls libm at runtime, but the references still resolve to real kernels
       # now, and lossy decoders (AAC/Opus/Vorbis) need them to decode correctly.
       target_link_libraries(SOF INTERFACE avcodec swresample avutil)
+      # Encode mode: libshine MP3 encoder archive (built by ffmpeg.cmake
+      # section 3b when FFMPEG_ENC_MP3 is set). Linked AFTER avcodec,
+      # which references its shine_* symbols.
+      if(CONFIG_FFMPEG_ENC_MP3)
+        target_link_directories(SOF INTERFACE ${SHINE_INSTALL}/lib)
+        target_link_libraries(SOF INTERFACE shine)
+        add_dependencies(modules_sof shine_ext)
+      endif()
+      if(CONFIG_FFMPEG_ENC_AAC)
+        target_link_directories(SOF INTERFACE ${VO_AACENC_INSTALL}/lib)
+        target_link_libraries(SOF INTERFACE vo-aacenc)
+        target_include_directories(SOF INTERFACE ${VO_AACENC_INSTALL}/include)
+        zephyr_include_directories(${VO_AACENC_INSTALL}/include)
+        add_dependencies(modules_sof vo_aacenc_ext)
+      endif()
       # libm (newlib double math) LAST so libav*/libshine references
       # (modf/cos/sin/log/sqrt/exp2) resolve against it.
       target_link_libraries(SOF INTERFACE ${FFMPEG_TARGET_LIBM})

src/audio/ffmpeg_dec/Kconfig

@@ -51,6 +51,42 @@ config FFMPEG_DEC_MP3
 	  MPEG-1/2 Layer III decoder. Enables --enable-decoder=mp3 and the
 	  mpegaudio parser in the libavcodec build. Uses the float math layer.
 
+config FFMPEG_ENC_MP3
+	bool "MP3 encoder (libshine, fixed-point)"
+	help
+	  MPEG-1 Layer III encoder via libshine, a small fixed-point encoder
+	  (west-pinned; FFmpeg has no native MP3 encoder). Cross-builds libshine
+	  and enables --enable-libshine --enable-encoder=libshine. Fixed-point, so
+	  no float math dependency. The encoder is built into the archive; a module
+	  encode path (PCM->MP3) is a separate build mode.
+
+config FFMPEG_ENC_AAC
+	bool "AAC-LC encoder (vo-aacenc, fixed-point)"
+	help
+	  MPEG-4 AAC Low Complexity encoder via vo-aacenc, a lightweight 32-bit
+	  fixed-point integer encoder (west-pinned). Pure integer fixed-point, no
+	  float math dependency. Output is a standard ADTS AAC elementary stream.
+
+config FFMPEG_DEC_ENCODE_MODE
+	bool "Build as an audio encoder (PCM -> compressed) instead of a decoder [EXPERIMENTAL]"
+	help
+	  Build the module as an encoder: PCM in, compressed elementary stream out
+	  (AAC-LC via vo-aacenc or MP3 via libshine).
+
+choice
+	prompt "Default encoder for encode mode"
+	depends on FFMPEG_DEC_ENCODE_MODE
+	default FFMPEG_ENC_DEFAULT_AAC
+
+config FFMPEG_ENC_DEFAULT_AAC
+	bool "AAC-LC (vo-aacenc, fixed-point)"
+	select FFMPEG_ENC_AAC
+
+config FFMPEG_ENC_DEFAULT_MP3
+	bool "MP3 (libshine, fixed-point)"
+	select FFMPEG_ENC_MP3
+endchoice
+
 # Selected automatically when a decoder that needs IEEE float math is
 # built. Gates compilation of the fast single-precision libm (fastmathf.c).
 config FFMPEG_DEC_FLOAT_MATH

src/audio/ffmpeg_dec/ffmpeg.cmake

@@ -42,9 +42,9 @@ if(CONFIG_FFMPEG_DEC_MP3)
 	list(APPEND _ff_decoders mp3)
 	list(APPEND _ff_parsers  mpegaudio)
 endif()
-# A decoder is required.
-if(NOT _ff_decoders)
-	message(FATAL_ERROR "ffmpeg_dec: no decoder selected (Kconfig FFMPEG_DEC_*)")
+# A decoder is required unless this is an encoder-only build.
+if(NOT _ff_decoders AND NOT CONFIG_FFMPEG_ENC_MP3 AND NOT CONFIG_FFMPEG_ENC_AAC)
+	message(FATAL_ERROR "ffmpeg_dec: no decoder or encoder selected (Kconfig FFMPEG_DEC_*/FFMPEG_ENC_*)")
 endif()
 set(_ff_dec_cfg "")
 if(_ff_decoders)
@@ -348,7 +348,150 @@ if(CONFIG_FFMPEG_DEC_COLD_SPLIT)
 			${FFMPEG_INSTALL_DIR}/lib/libswresample.a)
 endif()
 
+# --- 3b. MP3 encoder via libshine (fixed-point; FFmpeg has no native one) ---
 set(_ff_cfg_env "PATH=${_tc_dir}:$ENV{PATH}")
+set(_ff_shine_cfg "")
+set(_ff_shine_dep "")
+if(CONFIG_FFMPEG_ENC_MP3)
+	set(SHINE_SRC "${sof_top_dir}/../modules/audio/shine")
+	if(NOT EXISTS "${SHINE_SRC}/src/lib/layer3.h")
+		message(FATAL_ERROR "ffmpeg_dec: libshine source not at '${SHINE_SRC}'; run 'west update'")
+	endif()
+	set(SHINE_INSTALL "${CMAKE_CURRENT_BINARY_DIR}/shine-install")
+	file(MAKE_DIRECTORY "${SHINE_INSTALL}/lib/pkgconfig" "${SHINE_INSTALL}/include/shine")
+	# pkg-config file for FFmpeg's require_pkg_config libshine.
+	file(WRITE "${SHINE_INSTALL}/lib/pkgconfig/shine.pc"
+"prefix=${SHINE_INSTALL}
+libdir=\${prefix}/lib
+includedir=\${prefix}/include
+Name: shine
+Description: Shine fixed-point MP3 encoder
+Version: 3.1.1
+Libs: -L\${libdir} -lshine ${CMAKE_CURRENT_BINARY_DIR}/shine_cfgstub.o
+Cflags: -I\${includedir}
+")
+	# FFmpeg's -lshine link *test* pulls newlib malloc -> Zephyr runtime syms
+	# (z_errno_wrap, ...) that only exist at module load. Provide dummies so the
+	# configure test links; --extra-ldflags only affects tests, not the .a build.
+	file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/shine_cfgstub.c"
+"int z_errno_wrap(void){return 0;}
+void *stdout;
+int open(const char *p, int f, ...){return -1;}
+void *sbrk(int i){return (void *)-1;}
+")
+	# libshine's lib needs no config.h; build the objects directly and archive
+	# (its autotools CLI/shared link cannot work bare-metal).
+	file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/shine-build.sh"
+"#!/bin/sh
+set -e
+export PATH=${_tc_dir}:\$PATH
+CC=\"${_ff_cc}\"
+mkdir -p ${CMAKE_CURRENT_BINARY_DIR}/shine-obj
+for f in ${SHINE_SRC}/src/lib/*.c; do
+	\$CC -O2 -fPIC -mlongcalls -mtext-section-literals -DSHINE_HAVE_BSWAP_H \\
+		-I${SHINE_SRC}/src/lib -c \"\$f\" \\
+		-o ${CMAKE_CURRENT_BINARY_DIR}/shine-obj/\$(basename \"\$f\").o
+done
+${_ff_cross_prefix}ar rcs ${SHINE_INSTALL}/lib/libshine.a ${CMAKE_CURRENT_BINARY_DIR}/shine-obj/*.o
+cp ${SHINE_SRC}/src/lib/layer3.h ${SHINE_INSTALL}/include/shine/layer3.h
+\$CC -fPIC -c ${CMAKE_CURRENT_BINARY_DIR}/shine_cfgstub.c \\
+	-o ${CMAKE_CURRENT_BINARY_DIR}/shine_cfgstub.o
+")
+	add_custom_command(
+		OUTPUT "${SHINE_INSTALL}/lib/libshine.a" "${CMAKE_CURRENT_BINARY_DIR}/shine_cfgstub.o"
+		COMMAND sh "${CMAKE_CURRENT_BINARY_DIR}/shine-build.sh"
+		VERBATIM)
+	add_custom_target(shine_ext DEPENDS "${SHINE_INSTALL}/lib/libshine.a")
+
+	set(_ff_cfg_env "PATH=${_tc_dir}:$ENV{PATH}" "PKG_CONFIG_PATH=${SHINE_INSTALL}/lib/pkgconfig")
+	# NOTE: the cfgstub is scoped to libshine's OWN detection via shine.pc
+	# Libs (as an object), NOT a global --extra-ldflags. A global stub makes
+	# FFmpeg's generic check_func tests (posix_memalign/strerror_r/iconv)
+	# link against sbrk and false-positive HAVE_*=1, emitting libc calls that
+	# do not exist in the =y newlib env -> final firmware link fails. Scoping
+	# keeps this build's FFmpeg config identical to the decoder builds.
+	# --disable-iconv guards the one live check (iconv, probed after libshine).
+	set(_ff_shine_cfg --enable-libshine --enable-encoder=libshine --pkg-config=pkg-config
+		--disable-iconv
+		# The precomputed shine init tables (shine_precomp.h) add ~52KB of
+		# .rodata to libshine. FFmpeg's bare-metal -lshine configure *probe*
+		# links against the default GNU linker script whose 'flash' region is
+		# only 64KB, so the probe overflows ("region flash overflowed"). Grow
+		# the probe's flash region via --defsym. This affects configure test
+		# links ONLY (--disable-programs builds .a archives, no real link) and
+		# provides no symbols, so unlike a global libc stub it cannot trigger
+		# false-positive HAVE_* detection.
+		"--extra-ldflags=-Wl,--defsym,__flash_size=0x400000")
+	set(_ff_shine_dep shine_ext)
+	message(STATUS "ffmpeg_dec: enabling MP3 encoder via libshine (${SHINE_SRC})")
+endif()
+
+# --- 3c. AAC encoder via vo-aacenc (fixed-point integer AAC-LC) ---
+set(_ff_vo_aacenc_dep "")
+if(CONFIG_FFMPEG_ENC_AAC)
+	set(VO_AACENC_SRC "${sof_top_dir}/../modules/audio/vo-aacenc")
+	if(NOT EXISTS "${VO_AACENC_SRC}/common/include/voAAC.h")
+		message(FATAL_ERROR "ffmpeg_dec: vo-aacenc source not at '${VO_AACENC_SRC}'; run 'west update'")
+	endif()
+	set(VO_AACENC_INSTALL "${CMAKE_CURRENT_BINARY_DIR}/vo-aacenc-install")
+	file(MAKE_DIRECTORY "${VO_AACENC_INSTALL}/lib" "${VO_AACENC_INSTALL}/include/vo-aacenc")
+
+	file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/vo-aacenc-build.sh"
+"#!/bin/sh
+set -e
+export PATH=${_tc_dir}:\$PATH
+CC=\"${_ff_cc}\"
+mkdir -p ${CMAKE_CURRENT_BINARY_DIR}/vo-aacenc-obj
+SRCS=\"\
+${VO_AACENC_SRC}/common/cmnMemory.c \
+${VO_AACENC_SRC}/aacenc/basic_op/basicop2.c \
+${VO_AACENC_SRC}/aacenc/basic_op/oper_32b.c \
+${VO_AACENC_SRC}/aacenc/src/aac_rom.c \
+${VO_AACENC_SRC}/aacenc/src/aacenc.c \
+${VO_AACENC_SRC}/aacenc/src/aacenc_core.c \
+${VO_AACENC_SRC}/aacenc/src/adj_thr.c \
+${VO_AACENC_SRC}/aacenc/src/band_nrg.c \
+${VO_AACENC_SRC}/aacenc/src/bit_cnt.c \
+${VO_AACENC_SRC}/aacenc/src/bitbuffer.c \
+${VO_AACENC_SRC}/aacenc/src/bitenc.c \
+${VO_AACENC_SRC}/aacenc/src/block_switch.c \
+${VO_AACENC_SRC}/aacenc/src/channel_map.c \
+${VO_AACENC_SRC}/aacenc/src/dyn_bits.c \
+${VO_AACENC_SRC}/aacenc/src/grp_data.c \
+${VO_AACENC_SRC}/aacenc/src/interface.c \
+${VO_AACENC_SRC}/aacenc/src/line_pe.c \
+${VO_AACENC_SRC}/aacenc/src/memalign.c \
+${VO_AACENC_SRC}/aacenc/src/ms_stereo.c \
+${VO_AACENC_SRC}/aacenc/src/pre_echo_control.c \
+${VO_AACENC_SRC}/aacenc/src/psy_configuration.c \
+${VO_AACENC_SRC}/aacenc/src/psy_main.c \
+${VO_AACENC_SRC}/aacenc/src/qc_main.c \
+${VO_AACENC_SRC}/aacenc/src/quantize.c \
+${VO_AACENC_SRC}/aacenc/src/sf_estim.c \
+${VO_AACENC_SRC}/aacenc/src/spreading.c \
+${VO_AACENC_SRC}/aacenc/src/stat_bits.c \
+${VO_AACENC_SRC}/aacenc/src/tns.c \
+${VO_AACENC_SRC}/aacenc/src/transform.c \
+\"
+for f in \$SRCS; do
+	\$CC -O2 -DNDEBUG -fPIC -mlongcalls -mtext-section-literals -D__unused= \\
+		-I${VO_AACENC_SRC}/aacenc/inc \\
+		-I${VO_AACENC_SRC}/aacenc/basic_op \\
+		-I${VO_AACENC_SRC}/common/include \\
+		-c \"\$f\" \\
+		-o ${CMAKE_CURRENT_BINARY_DIR}/vo-aacenc-obj/\$(basename \"\$f\").o
+done
+${_ff_cross_prefix}ar rcs ${VO_AACENC_INSTALL}/lib/libvo-aacenc.a ${CMAKE_CURRENT_BINARY_DIR}/vo-aacenc-obj/*.o
+cp ${VO_AACENC_SRC}/common/include/*.h ${VO_AACENC_INSTALL}/include/vo-aacenc/
+")
+	add_custom_command(
+		OUTPUT "${VO_AACENC_INSTALL}/lib/libvo-aacenc.a"
+		COMMAND sh "${CMAKE_CURRENT_BINARY_DIR}/vo-aacenc-build.sh"
+		VERBATIM)
+	add_custom_target(vo_aacenc_ext DEPENDS "${VO_AACENC_INSTALL}/lib/libvo-aacenc.a")
+	set(_ff_vo_aacenc_dep vo_aacenc_ext)
+	message(STATUS "ffmpeg_dec: enabling AAC encoder via vo-aacenc (${VO_AACENC_SRC})")
+endif()
 
 # --- 4. Configure + make + install (out-of-tree; source must be clean) ---
 set(_ff_byproducts
@@ -357,6 +500,7 @@ set(_ff_byproducts
 	${FFMPEG_INSTALL_DIR}/lib/libswresample.a)
 
 ExternalProject_Add(ffmpeg_ext
+	DEPENDS ${_ff_shine_dep} ${_ff_vo_aacenc_dep}
 	SOURCE_DIR      "${SOF_FFMPEG_SRC_DIR}"
 	BUILD_IN_SOURCE 0
 	CONFIGURE_COMMAND
@@ -378,6 +522,7 @@ ExternalProject_Add(ffmpeg_ext
 			--disable-runtime-cpudetect --disable-debug
 			--enable-avcodec --enable-avutil --enable-swresample
 			${_ff_dec_cfg}
+			${_ff_shine_cfg}
 			--enable-small --enable-pic --enable-hardcoded-tables
 			"--extra-cflags=${_ff_extra_cflags}"
 	BUILD_COMMAND