Anime Signs/Songs Subtitle Forcing Script

[iwalton3]

Please Note: A similar function is now available in Plex-MPV-Shim, which is my custom client for Plex. It is easier to use than this script and works on both Linux and Windows.

GitHub: https://github.com/iwalton3/media-scripts/tree/master/force-signs

Plex by default does not enable subtitle tracks for signs and songs on dual audio or English dubbed anime unless they are forced by the encoder. This script will automatically scan your media files and force these subtitle tracks for you, saving you the hassle. It requires python3 and mkvtoolnix. You can run it over all files like this:

find /path/to/Plex/ -iname '*.mkv' | while read -r file; do ./plex-force-signs.py "$file" 2>&1 | tee -a signs.log; done

#!/usr/bin/env python3
import sys
import subprocess
import json

fname = sys.argv[1]

def sign_weight(text):
    if not text:
        return 0
    lower_text = text.lower()
    has_songs = "op/ed" in lower_text or "song" in lower_text or "lyric" in lower_text
    has_signs = "sign" in lower_text                                       
    custom = "[" in lower_text or "(" in lower_text
    vendor = "bd" in lower_text or "retail" in lower_text
    weight = 900

    if not (has_songs or has_signs):
        return 0
    if has_songs:
        weight -= 200
    if has_signs:
        weight -= 300
    if custom:
        weight -= 100
    if vendor:
        weight += 50
    return weight

metadata = json.loads(subprocess.check_output(["mkvmerge","-J",fname]).decode())

is_english = False
sign_track = None
sign_track_weight = 1000
forced_uid = None

for track in metadata["tracks"]:
    props = track["properties"]
    if track["type"] == "audio" and props["language"] == "eng":
        is_english = True
    if track["type"] == "subtitles":
        if props.get("language") == "eng":
            untagged = False
            eng_subs = True
        elif "english" in (props.get("track_name") or "").lower():
            untagged = True
            eng_subs = True
        else:
            untagged = False
            eng_subs = False
        weight = sign_weight(props.get("track_name"))        
        if weight and eng_subs:
            if sign_track_weight > weight:
                sign_track_weight = weight
                sign_track = props["uid"]
        if props["forced_track"]:
            if forced_uid != None:
                print("Fatal error",fname,"Multiple forced tracks!")
                sys.exit(1)
            forced_uid = props["uid"]

if not is_english:
    print("Skipping file",fname,"Not in english!")
    sys.exit(0)

if forced_uid != None and sign_track == forced_uid:
    print("Skipping file",fname,"Already forced.")
    sys.exit(0)

if sign_track == None:
    print("Skipping file",fname,"No sign track.")
    sys.exit(0)

if forced_uid != None:
    print("Remove forced",fname,forced_uid)
    subprocess.Popen(["mkvpropedit",fname,"--edit","track:="+str(forced_uid),"--set","flag-forced=false"])

print("Set forced",fname,sign_track)
subprocess.Popen(["mkvpropedit",fname,"--edit","track:="+str(sign_track),"--set","flag-forced=true"])