Generate various audio formats with sox, changing parameters

iterate_sox_encodings.sh

#!/usr/bin/env bash

base_dir="tmp/test_sox"
mkdir -p "${base_dir}"

base_file="${base_dir}/base.wav"
sox --rate 8000 --channels 1 --null "${base_file}" synth 1 sawtooth 1
for type in wav mp3 flac vorbis sph amr-nb amb gsm htk; do
    for encoding in no_encoding signed-integer unsigned-integer floating-point mu-law a-law; do
        prefix="${base_dir}/${type}/${encoding}"
        mkdir -p "${prefix}"
        for bits in no_bits 8 16 24 32; do
            filepath="${prefix}/${bits}.${type}"
            printf "%s\n" "${filepath}"
            options=(--type "${type}")
            if [ "${encoding}" != "no_encoding" ]; then
                options+=(--encoding "${encoding}")
            fi
            if [ "${bits}" != "no_bits" ]; then
                options+=(--bits "${bits}")
            fi

            sox "${base_file}" --rate 8000 --channels 1 "${options[@]}" "${filepath}" 2>&1 #  | grep WARN | grep -v 'dither'
        done
        soxi "${prefix}/"* | grep 'Input File\|bit'
    done
done