Python script: Změna časů chainů a markerů mlt souboru pro zdrojové video 2x zrychlené

 

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
fix_times_one_script_fixed.py
Opravená verze — škáluje jen to, co se smí (bez double-scalingu a bez škálování length média)
"""

from xml.etree import ElementTree as ET
from pathlib import Path
from decimal import Decimal, getcontext, ROUND_HALF_UP
import re, shutil, sys

# ======= NASTAVENÍ =======
INPUT_FILE  = Path("./Jede vlak.mlt")
OUTPUT_FILE = Path("./Jede vlak_fixed.mlt")
SCALE = Decimal("0.5")                          # 0.5 = polovina času
RESOURCE_FROM = "/1/"                           # nebo None
RESOURCE_TO   = "/2/"
# ==================================================

getcontext().prec = 28
getcontext().rounding = ROUND_HALF_UP

TIME_RE = re.compile(r'^(?P<h>\d{2}):(?P<m>\d{2}):(?P<s>\d{2})(?:\.(?P<frac>\d+))?$')

def parse_time_to_decimal(text):
    if text is None:
        return None, 0
    t = text.strip()
    m = TIME_RE.match(t)
    if not m:
        return None, 0
    h = int(m.group('h'))
    mm = int(m.group('m'))
    ss = int(m.group('s'))
    frac = m.group('frac') or ""
    frac_len = len(frac)
    frac_dec = Decimal("0." + frac) if frac_len > 0 else Decimal(0)
    total = Decimal(h)*3600 + Decimal(mm)*60 + Decimal(ss) + frac_dec
    return total, frac_len

def format_decimal_seconds(total_seconds: Decimal, frac_len: int = 3):
    if total_seconds < 0:
        total_seconds = Decimal(0)
    hours = int(total_seconds // 3600)
    rem = total_seconds - Decimal(hours)*3600
    minutes = int(rem // 60)
    sec_dec = rem - Decimal(minutes)*60
    if frac_len > 0:
        q = Decimal(1).scaleb(-frac_len)
        sec_q = sec_dec.quantize(q, rounding=ROUND_HALF_UP)
        if sec_q >= 60:
            sec_q -= 60
            minutes += 1
            if minutes >= 60:
                minutes -= 60
                hours += 1
        frac_part = f"{sec_q - int(sec_q):.{frac_len}f}"[1:]
        sec_str = f"{int(sec_q):02d}{frac_part}"
    else:
        sec_str = f"{int(sec_dec):02d}"
    return f"{hours:02d}:{minutes:02d}:{sec_str}"

def scale_time_text(txt, scale):
    total, frac_len = parse_time_to_decimal(txt)
    if total is None:
        return None
    new_total = total * scale
    target_frac = frac_len if frac_len > 0 else 3
    return format_decimal_seconds(new_total, target_frac)

def backup_file(p: Path):
    bak = p.with_suffix(p.suffix + ".bak")
    if not bak.exists():
        shutil.copy2(p, bak)
    return bak

def main():
    if not INPUT_FILE.exists():
        print("Chyba: vstupní soubor nenalezen:", INPUT_FILE)
        sys.exit(1)
    xml = INPUT_FILE.read_text(encoding="utf-8")
    root = ET.fromstring(xml)

    counts = {"tractor":0, "chain_out":0, "playlist_entry":0, "markers":0, "resource_repl":0}
    samples = []

    # 1. playlist entry in/out
    for playlist in root.findall(".//playlist"):
        for entry in playlist.findall("entry"):
            for a in ("in", "out"):
                v = entry.get(a)
                new = scale_time_text(v, SCALE) if v else None
                if new:
                    entry.set(a, new)
                    counts["playlist_entry"] += 1
                    samples.append(("playlist_entry", entry.get("producer"), a, v, new))

    # 2. tractor in/out
    for tractor in root.findall(".//tractor"):
        for a in ("in", "out"):
            v = tractor.get(a)
            new = scale_time_text(v, SCALE) if v else None
            if new:
                tractor.set(a, new)
                counts["tractor"] += 1
                samples.append(("tractor", tractor.get("id"), a, v, new))

    # 3. chains: ŠKÁLUJEME POUZE out atribut (NE length property!)
    for chain in root.findall(".//chain"):
        for a in ("in", "out"):   # in obvykle není, ale pro jistotu
            v = chain.get(a)
            new = scale_time_text(v, SCALE) if v else None
            if new:
                chain.set(a, new)
                counts["chain_out"] += 1
                samples.append(("chain_out", chain.get("id"), a, v, new))
        # ŽÁDNÉ škálování <property name="length"> !!!

        # resource replacement (pokud chceš)
        if RESOURCE_FROM:
            for prop in chain.findall("property[@name='resource']"):
                if prop.text:
                    old = prop.text
                    newres = old.replace(RESOURCE_FROM, RESOURCE_TO)
                    if newres != old:
                        prop.text = newres
                        counts["resource_repl"] += 1
                        samples.append(("resource", chain.get("id"), old, newres))

    # 4. markery – jen jednou!
    for props in root.findall(".//properties[@name='shotcut:markers']"):
        for marker in props.findall("properties"):
            for prop_name in ("start", "end"):
                prop = marker.find(f"property[@name='{prop_name}']")
                if prop is not None and prop.text:
                    new = scale_time_text(prop.text, SCALE)
                    if new:
                        prop.text = new
                        counts["markers"] += 1
                        samples.append((f"marker_{prop_name}", marker.get("name"), prop.text, new))

    # ZÁLOHA + ZÁPIS
    bak = backup_file(INPUT_FILE)
    print("Záloha:", bak)
    OUTPUT_FILE.write_text(ET.tostring(root, encoding="utf-8", method="xml").decode("utf-8"), encoding="utf-8")
    print("Uloženo:", OUTPUT_FILE)

    # Souhrn
    print("\nZměny:")
    for k, v in counts.items():
        print(f" - {k}: {v}")
    print("\nUkázka (prvních 30):")
    for s in samples[:30]:
        print(s)

if __name__ == "__main__":
    main()