DSD to FLAC conversion using SoX DSD. Original by @hyperknot. Scans the file once to determine optimum gain, then converts using that. You can get SoX DSD binaries from https://audiodigitale.eu/repo/sox/

dsd2flac.py

#!/usr/bin/env python3

import pathlib
import subprocess
import sys
import shutil
import math

root = pathlib.Path(__file__).parent.resolve()
target_root = root / 'dsd'


def convert_folder(folder):

    files = folder.glob('*.dsf')
    for file in files:
        relative_dir = file.parent.relative_to(root)
        target_dir = target_root / relative_dir
        target_dir.mkdir(exist_ok=True, parents=True)

        tmp_path = target_dir / 'tmp.flac'
        tmp_path.unlink(missing_ok=True)

        target_path = target_dir / (file.stem + '.flac')
        if target_path.is_file():
            continue

        print(f'  {target_path}')

        cmdCalc = [
            'sox',
            '-V3',
            file,
            '--bits',
            '24',
            '-C',
            '0',
            tmp_path,
            #
            'rate',
            '-ub74',
            '176400',
            'sinc',
            '-25k',
            'stats',
        ]

        print("\nCalculating file levels...\n")
        proc = subprocess.Popen(cmdCalc, stderr=subprocess.PIPE, text=True)
        while True:
            line = proc.stderr.readline()
            if not line:
                break
            if 'Pk lev dB' in line:
                levels = line.split()

        detectedPeak = abs(float(levels[3]))
        calcNorm = math.ceil(detectedPeak)

        if calcNorm >= 6:
            print("DSD appears to be mastered according to Scarlet Book loudness specs...")
            gain = 6
        elif calcNorm <= 5:
            print(f"Found a weird one Bobby...detected peak was {detectedPeak}, using gain {calcNorm}")
            gain = calcNorm

        print(f"\nConverting file with gain level: {gain}...\n")

        cmdConv = [
            'sox',
            '-V3',
            file,
            '--bits',
            '24',
            '-C',
            '8',
            tmp_path,
            #
            'rate',
            '-ub74',
            '176400',
            #
            'gain',
            str(gain),
            #
            'sinc',
            '-25k',
            'stats',
        ]

        subprocess.run(cmdConv, text=True, capture_output=True)

        tmp_path.rename(target_path)

    return dict(success=True, target_dir=target_dir)


def main():
    dsd_folders = set()

    dsd_files = root.glob('**/*.dsf')
    for file in dsd_files:
        folder = file.parent
        dsd_folders.add(folder)
    print(f"Got folders: {dsd_folders}")
    for folder in sorted(dsd_folders):
        print(f'\n\nProcessing {folder}')

        r = convert_folder(folder)

main()