import subprocess

def extract_audio_ffmpeg(in_video, out_audio="temp_audio.wav"):
    cmd = [
        "ffmpeg", "-y",
        "-i", in_video,
        "-vn",
        "-acodec", "pcm_s16le",
        "-ar", "16000",
        "-ac", "1",
        out_audio
    ]
    result = subprocess.run(cmd, capture_output=True)
    if result.returncode != 0:
        raise RuntimeError(f"FFmpeg audio extraction failed: {result.stderr.decode()}")
    return out_audio

def apply_edits(original_video, edit_instructions):
    """
    Suppose edit_instructions is a JSON or dictionary specifying which segments to keep.
    We'll write them to a concat file or do a more advanced approach.
    """
    # parse or generate concat script
    # run ffmpeg to produce "edited_video.mp4"
    out_path = "edited_video.mp4"
    # ...
    return out_path