timecodes ¶

@classmethod
def from_clip(
    cls: type[KeyframesBoundT], clip: vs.VideoNode, mode: SceneChangeMode | int = WWXD, height: int | None = 360,
    **kwargs: Any
) -> KeyframesBoundT:

    mode = SceneChangeMode(mode)

    clip = mode.prepare_clip(clip, height)

    frames = clip_async_render(clip, None, 'Detecting scene changes...', mode.lambda_cb(), **kwargs)

    return cls(Sentinel.filter(frames))

@classmethod
def from_file(cls: type[KeyframesBoundT], file: FilePathType, **kwargs: Any) -> KeyframesBoundT:
    file = SPath(str(file)).resolve()

    if not file.exists():
        raise FileNotFoundError

    if file.stat().st_size <= 0:
        raise OSError('File is empty!')

    lines = [
        line.strip() for line in file.read_lines('utf-8')
        if line and not line.startswith('#')
    ]

    if not lines:
        raise ValueError('No keyframe could be found!')

    kf_type: int | None = None

    line = lines[0].lower()

    if line.startswith('fps'):
        kf_type = Keyframes.XVID
    elif line.startswith(('i', 'b', 'p', 'n')):
        kf_type = Keyframes.V1

    if kf_type is None:
        raise ValueError('Could not determine keyframe file type!')

    if kf_type == Keyframes.V1:
        return cls(i for i, line in enumerate(lines) if line.startswith('i'))

    if kf_type == Keyframes.XVID:
        split_lines = [line.split(' ') for line in lines]

        return cls(int(n) for n, t, *_ in split_lines if t.lower() == 'i')

    raise ValueError('Invalid keyframe file type!')

@classmethod
def from_param(cls: type[KeyframesBoundT], clip: vs.VideoNode, param: KeyframesBoundT | str) -> KeyframesBoundT:
    if isinstance(param, str):
        return cls.unique(clip, param)

    if isinstance(param, cls):
        return param

    return cls(param)

@inject_self.with_args(_dummy=True)
def to_clip(
    self, clip: vs.VideoNode, *, mode: SceneChangeMode | int = WWXD, height: int | None = 360,
    prop_key: str = next(iter(SceneChangeMode.SCXVID.prop_keys)), scene_idx_prop: bool = False
) -> vs.VideoNode:
    from ..utils import replace_ranges

    propset_clip = clip.std.SetFrameProp(prop_key, True)

    if self._dummy:
        mode = SceneChangeMode(mode)

        prop_clip, callback = mode.prepare_clip(clip, height), mode.check_cb()

        out = replace_ranges(clip, propset_clip, callback, prop_src=prop_clip)
    else:
        out = replace_ranges(clip, propset_clip, self)

    if not scene_idx_prop:
        return out

    def _add_scene_idx(n: int, f: vs.VideoFrame) -> vs.VideoFrame:
        f = f.copy()

        f.props._SceneIdx = self.scenes.indices[n]

        return f

    return out.std.ModifyFrame(out, _add_scene_idx)

def to_file(
    self, out: FilePathType, format: int = V1, func: FuncExceptT | None = None,
    header: bool = True, force: bool = False
) -> None:
    from ..utils import check_perms

    func = func or self.to_file

    out_path = Path(str(out)).resolve()

    if out_path.exists():
        if not force and out_path.stat().st_size > 0:
            return

        out_path.unlink()

    out_path.parent.mkdir(parents=True, exist_ok=True)

    check_perms(out_path, 'w+', func=func)

    if format == Keyframes.V1:
        out_text = [
            *(['# keyframe format v1', 'fps 0', ''] if header else []),
            *(f'{n} I -1' for n in self), ''
        ]
    elif format == Keyframes.XVID:
        lut_self = set(self)
        out_text = [
            *(['# XviD 2pass stat file', '',] if header else []),
            *(
                (lut_self.remove(i) or 'i') if i in lut_self else 'b'  # type: ignore
                for i in range(max(self))
            )
        ]

    out_path.unlink(True)
    out_path.touch()
    out_path.write_text('\n'.join(out_text))

@classmethod
def unique(
    cls: type[KeyframesBoundT], clip: vs.VideoNode, key: str, **kwargs: Any
) -> KeyframesBoundT:
    file = cls._get_unique_path(clip, key)

    if file.exists():
        if file.stat().st_size > 0:
            return cls.from_file(file, **kwargs)

        file.unlink()

    keyframes = cls.from_clip(clip, **kwargs)
    keyframes.to_file(file, force=True)

    return keyframes

@classmethod
def from_file(
    cls, file: FilePathType, ref_or_length: int | vs.VideoNode | None = None, *, func: FuncExceptT | None = None
) -> LWIndex:
    func = func or cls.from_file

    file = Path(str(file)).resolve()

    length = ref_or_length.num_frames if isinstance(ref_or_length, vs.VideoNode) else ref_or_length

    data = file.read_text('latin1').splitlines()

    indexstart, indexend = data.index("</StreamInfo>") + 1, data.index("</LibavReaderIndex>")

    if length and (idxlen := ((indexend - indexstart) // 2)) != length:
        raise FramesLengthError(
            func, '', 'index file length mismatch with specified length!',
            reason=dict(index=idxlen, clip=length)
        )

    sinfomatch = LWIndex.Regex.streaminfo.match(data[indexstart - 2])

    timebase_num, timebase_den = [
        int(i) for i in sinfomatch.group("TimeBase").split("/")  # type: ignore
    ]

    streaminfo = LWIndex.StreamInfo(
        int(sinfomatch.group("Codec")),  # type: ignore
        Fraction(timebase_num, timebase_den),
        int(sinfomatch.group("Width")),  # type: ignore
        int(sinfomatch.group("Height")),  # type: ignore
        sinfomatch.group("Format"),  # type: ignore
        Matrix(int(sinfomatch.group("ColorSpace"))),  # type: ignore
    )

    frames = sorted([
        LWIndex.Frame(*(
            int(x) for x in (
                match[0].group(key) for match in [  # type: ignore
                    (LWIndex.Regex.frame_first.match(data[i]), ['Index', 'POS', 'PTS', 'DTS', 'EDI']),
                    (LWIndex.Regex.frame_second.match(data[i + 1]), ['Key', 'Pic', 'POC', 'Repeat', 'Field'])
                ] for key in match[1]
            )
        ))
        for i in range(indexstart, indexend, 2)
    ], key=lambda x: x.pts)

    keyframes = Keyframes(i for i, f in enumerate(frames) if f.key)

    return LWIndex(streaminfo, frames, keyframes)

def to_fraction(self) -> Fraction:
    """Convert the Timecode to a Fraction that represents the FPS."""

    return Fraction(self.numerator, self.denominator)

@classmethod
def accumulate_norm_timecodes(cls, timecodes: Timecodes | dict[tuple[int, int], Fraction]) -> tuple[
    Fraction, dict[Fraction, list[tuple[int, int]]]
]:
    if isinstance(timecodes, Timecodes):
        timecodes = timecodes.to_normalized_ranges()

    major_time, minor_fps = cls.separate_norm_timecodes(timecodes)

    acc_ranges = dict[Fraction, list[tuple[int, int]]]()

    for k, v in minor_fps.items():
        if v not in acc_ranges:
            acc_ranges[v] = []

        acc_ranges[v].append(k)

    return major_time, acc_ranges

def assume_vfr(self, clip: vs.VideoNode, func: FuncExceptT | None = None) -> vs.VideoNode:
    """
    Force the given clip to be assumed to be vfr by other applications.

    :param clip:        Clip to process.
    :param func:        Function returned for custom error handling.
                        This should only be set by VS package developers.

    :return:            Clip that should always be assumed to be vfr by other applications.
    """
    from ..utils import replace_ranges

    func = func or self.assume_vfr

    major_time, minor_fps = self.accumulate_norm_timecodes(self)

    assumed_clip = clip.std.AssumeFPS(None, major_time.numerator, major_time.denominator)

    for other_fps, fps_ranges in minor_fps.items():
        assumed_clip = replace_ranges(
            assumed_clip, clip.std.AssumeFPS(None, other_fps.numerator, other_fps.denominator),
            fps_ranges, mismatch=True
        )

    return assumed_clip

@classmethod
def from_clip(cls: type[TimecodesBoundT], clip: vs.VideoNode, **kwargs: Any) -> TimecodesBoundT:
    """
    Get the timecodes from a given clip.

    :param clip:        Clip to gather metrics from.
    :param kwargs:      Keyword arguments to pass on to `clip_async_render`.
    """
    def _get_timecode(n: int, f: vs.VideoFrame) -> Timecode:
        return Timecode(n, f.props._DurationNum, f.props._DurationDen)

    return cls(clip_async_render(clip, None, 'Fetching timecodes...', _get_timecode, **kwargs))

@classmethod  # type: ignore
def from_file(
    cls: type[TimecodesBoundT], file: FilePathType, ref_or_length: int | vs.VideoNode, den: int | None = None,
    *, func: FuncExceptT | None = None
) -> TimecodesBoundT:
    """
    Read the timecodes from a given file.

    :param file:            File to read.
    :param ref_or_length:   Reference clip to get the total number of frames from.
                            If int, take that as the total number of frames.
    :param den:             The denominator. If None, try to obtain it from the ref if possible,
                            else fall back to 1001.
    :param func:            Function returned for custom error handling.
                            This should only be set by VS package developers.
    """
    func = func or cls.from_file

    file = Path(str(file)).resolve()

    length = ref_or_length if isinstance(ref_or_length, int) else ref_or_length.num_frames

    fb_den = (
        None if ref_or_length.fps_den in {0, 1} else ref_or_length.fps_den
    ) if isinstance(ref_or_length, vs.VideoNode) else None

    denominator = den or fb_den or 1001

    version, *_timecodes = file.read_text().splitlines()

    if 'v1' in version:
        def _norm(xd: str) -> Fraction:
            return Fraction(round(denominator / float(xd)), denominator)

        assume = None

        timecodes_d = dict[tuple[int | None, int | None], Fraction]()

        for line in _timecodes:
            if line.startswith('#'):
                continue

            if line.startswith('Assume'):
                assume = _norm(_timecodes[0][7:])
                continue

            starts, ends, _fps = line.split(',')
            timecodes_d[(int(starts), int(ends) + 1)] = _norm(_fps)

        norm_timecodes = cls.normalize_range_timecodes(timecodes_d, length, assume)
    elif 'v2' in version:
        timecodes_l = [float(t) for t in _timecodes if not t.startswith('#')]
        norm_timecodes = [
            Fraction(int(denominator * float(f'{round((x - y) * 100, 4) / 100000:.08f}'[:-1])), denominator)
            for x, y in zip(timecodes_l[1:], timecodes_l[:-1])
        ]
    else:
        raise CustomValueError('timecodes file not supported!', func, file)

    if len(norm_timecodes) != length:
        raise FramesLengthError(
            func, '', 'timecodes file length mismatch with specified length!',
            reason=dict(timecodes=len(norm_timecodes), clip=length)
        )

    return cls(
        Timecode(i, f.numerator, f.denominator) for i, f in enumerate(norm_timecodes)
    )

@classmethod
def normalize_range_timecodes(
    cls, timecodes: dict[tuple[int | None, int | None], Fraction], length: int, assume: Fraction | None = None
) -> list[Fraction]:
    """Convert from normalized ranges to a list of Fractions."""

    from .funcs import fallback

    norm_timecodes = [assume] * length if assume else list[Fraction]()

    for (startn, endn), fps in timecodes.items():
        start = max(fallback(startn, 0), 0)
        end = fallback(endn, length)

        if end > len(norm_timecodes):
            norm_timecodes += [fps] * (end - len(norm_timecodes))

        norm_timecodes[start:end] = [fps] * (end - start)

    return norm_timecodes

@classmethod
def separate_norm_timecodes(cls, timecodes: Timecodes | dict[tuple[int, int], Fraction]) -> tuple[
    Fraction, dict[tuple[int, int], Fraction]
]:
    if isinstance(timecodes, Timecodes):
        timecodes = timecodes.to_normalized_ranges()

    times_count = {k: 0 for k in timecodes.values()}

    for v in timecodes.values():
        times_count[v] += 1

    major_count = max(times_count.values())
    major_time = next(t for t, c in times_count.items() if c == major_count)
    minor_fps = {r: v for r, v in timecodes.items() if v != major_time}

    return major_time, minor_fps

def to_file(self, out: FilePathType, format: int = V2, func: FuncExceptT | None = None) -> None:
    """
    Write timecodes to a file.

    This file should always be muxed into the video container when working with Variable Frame Rate video.

    :param out:         Path to write the file to.
    :param format:      Format to write the file to.
    """
    from ..utils import check_perms

    func = func or self.to_file

    out_path = Path(str(out)).resolve()

    check_perms(out_path, 'w+', func=func)

    InvalidTimecodeVersionError.check(self.to_file, format)

    out_text = [
        f'# timecode format v{format}'
    ]

    if format == Timecodes.V1:
        major_time, minor_fps = self.separate_norm_timecodes(self)

        out_text.append(f'Assume {round(float(major_time), 12)}')

        out_text.extend([
            ','.join(map(str, [*frange, round(float(fps), 12)]))
            for frange, fps in minor_fps.items()
        ])
    elif format == Timecodes.V2:
        acc = Fraction()    # in milliseconds

        for time in self + [Fraction()]:
            ns = round(acc * 10 ** 6)
            ms, dec = divmod(ns, 10 ** 6)
            out_text.append(f"{ms}.{dec:06}")
            acc += Fraction(time.numerator * 1000, time.denominator)

    out_path.unlink(True)
    out_path.touch()
    out_path.write_text('\n'.join(out_text + ['']))

def to_fractions(self) -> list[Fraction]:
    """Convert to a list of frame lengths, representing the individual framerates."""

    return list(
        Fraction(x.numerator, x.denominator)
        for x in self
    )

def to_normalized_ranges(self) -> dict[tuple[int, int], Fraction]:
    """Convert to a list of normalized frame ranges and their assigned framerate."""

    timecodes_ranges = dict[tuple[int, int], Fraction]()

    last_i = len(self) - 1
    last_tcode: tuple[int, Timecode] = (0, self[0])

    for tcode in self[1:]:
        start, ltcode = last_tcode

        if tcode != ltcode:
            timecodes_ranges[start, tcode.frame - 1] = 1 / ltcode.to_fraction()
            last_tcode = (tcode.frame, tcode)
        elif tcode.frame == last_i:
            timecodes_ranges[start, tcode.frame] = 1 / tcode.to_fraction()

    return timecodes_ranges