Best config for ffmpeg to convert MP3 file only - ffmpeg

Question

I want to compile FFMPEG to support conversion from MP3 to WAV and WAV to MP3.
as I only need that task, and output compiled size is really matter to me, Please correct me best compile config that accompilesh my requirement.
here is full config file:
function build_ffmpeg
{
echo "Starting build ffmpeg for $ARCH"
cd ffmpeg
./configure --target-os=linux \
--prefix=$PREFIX \
--enable-cross-compile \
--extra-libs="-lgcc" \
--arch=$ARCH \
--cc=$CC \
--cross-prefix=$CROSS_COMPILE \
--nm=$NM \
--sysroot=$PLATFORM \
--extra-cflags=" -O3 -fpic -DANDROID -DHAVE_SYS_UIO_H=1 -Dipv6mr_interface=ipv6mr_ifindex -fasm -Wno-psabi -fno-short-enums -fno-strict-aliasing -finline-limit=300 $OPTIMIZE_CFLAGS " \
--disable-shared \
--enable-static \
--enable-runtime-cpudetect \
--extra-ldflags="-Wl,-rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -nostdlib -lc -lm -ldl -llog -L$PREFIX/lib" \
--extra-cflags="-I$PREFIX/include" \
--disable-everything \
--enable-pthreads \
--enable-libass \
--enable-libvo-aacenc \
--enable-libvo-amrwbenc \
--enable-hwaccel=h264_vaapi \
--enable-hwaccel=h264_vaapi \
--enable-hwaccel=h264_dxva2 \
--enable-hwaccel=mpeg4_vaapi \
--enable-demuxer=mov \
--enable-demuxer=h264 \
--enable-demuxer=mpegvideo \
--enable-demuxer=h263 \
--enable-demuxer=mpegps \
--enable-demuxer=mjpeg \
--enable-demuxer=rtsp \
--enable-demuxer=rtp \
--enable-demuxer=hls \
--enable-demuxer=matroska \
--enable-muxer=rtsp \
--enable-muxer=mp4 \
--enable-muxer=mov \
--enable-muxer=mjpeg \
--enable-muxer=matroska \
--enable-protocol=crypto \
--enable-protocol=jni \
--enable-protocol=file \
--enable-encoder=libvo_amrwbenc \
--enable-decoder=amrwb \
--enable-muxer=mp2 \
--enable-bsfs \
--enable-decoders \
--enable-encoders \
--enable-parsers \
--enable-hwaccels \
--enable-muxers \
--enable-avformat \
--enable-avcodec \
--enable-avresample \
--enable-zlib \
--disable-doc \
--disable-ffplay \
--disable-ffmpeg \
--disable-ffplay \
--disable-ffprobe \
--disable-ffserver \
--disable-avfilter \
--disable-avdevice \
--enable-nonfree \
--enable-version3 \
--enable-memalign-hack \
--enable-asm \
$ADDITIONAL_CONFIGURE_FLAG
make clean
make -j4 install
make clean
cd ..
echo "FINISHED ffmpeg for $ARCH"
}
function build_one {
echo "Starting build one for $ARCH"
cd ffmpeg
${LD} -rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -L$PREFIX/lib -soname $SONAME -shared -nostdlib -Bsymbolic --whole-archive --no-undefined -o $OUT_LIBRARY -lavcodec -lavformat -lavresample -lavutil -lswresample -lass -lfreetype -lfribidi -lswscale -lvo-aacenc -lvo-amrwbenc -lc -lm -lz -ldl -llog --dynamic-linker=/system/bin/linker -zmuldefs $PREBUILT/lib/gcc/$EABIARCH/$COMPILATOR_VERSION/libgcc.a
cd ..
echo "FINISHED one for $ARCH"
}

Answer 1

./configure --disable-all --disable-autodetect --disable-network --enable-pthreads \
--enable-avcodec --enable-avformat --enable-swresample --enable-avfilter \
--enable-libmp3lame --enable-parser=mpegaudio --enable-demuxer=mp3,wav \
--enable-muxer=mp3,wav --enable-decoder=pcm*,mp3* --enable-encoder=pcm*,libmp3lame \
--enable-filter=aresample --enable-protocol=file --enable-ffmpeg --enable-small
Consider using libshine instead of libmp3lame is you need faster, but lower quality, MP3 encoding (especially on architectures without a FPU).
I usually don't recommend using --disable-all, but the size of the executable seems to be the most important factor for you. Using --disable-everything is easier to use because it does not disable the FFmpeg libraries, and is therefore less prone to forgotten components.
--disable-small optimizes for size instead of speed. It does make a size difference (1 MB vs 1.4 MB in this example), but I'm not sure how much of a speed difference it makes.
I did not include any additional options you may need for compiling for or on Android.
This may not work for MP3 inputs that contain album art because I did not enable any video options (specifically JPG and PNG related components). You may get by that by mapping just the audio with the -map option, such as with -map 0:a.