"""Decorators used by moviepy."""
import inspect
import os
import decorator
from moviepy.tools import convert_to_seconds
@decorator.decorator
def outplace(func, clip, *args, **kwargs):
"""Applies ``func(clip.copy(), *args, **kwargs)`` and returns ``clip.copy()``."""
new_clip = clip.copy()
func(new_clip, *args, **kwargs)
return new_clip
@decorator.decorator
def convert_masks_to_RGB(func, clip, *args, **kwargs):
"""If the clip is a mask, convert it to RGB before running the function."""
if clip.is_mask:
clip = clip.to_RGB()
return func(clip, *args, **kwargs)
@decorator.decorator
def apply_to_mask(func, clip, *args, **kwargs):
"""Applies the same function ``func`` to the mask of the clip created with
``func``.
"""
new_clip = func(clip, *args, **kwargs)
if getattr(new_clip, "mask", None):
new_clip.mask = func(new_clip.mask, *args, **kwargs)
return new_clip
@decorator.decorator
def apply_to_audio(func, clip, *args, **kwargs):
"""Applies the function ``func`` to the audio of the clip created with ``func``."""
new_clip = func(clip, *args, **kwargs)
if getattr(new_clip, "audio", None):
new_clip.audio = func(new_clip.audio, *args, **kwargs)
return new_clip
@decorator.decorator
def requires_duration(func, clip, *args, **kwargs):
"""Raises an error if the clip has no duration."""
if clip.duration is None:
raise ValueError("Attribute 'duration' not set")
else:
return func(clip, *args, **kwargs)
@decorator.decorator
def requires_fps(func, clip, *args, **kwargs):
"""Raises an error if the clip has no fps."""
if not hasattr(clip, "fps") or clip.fps is None:
raise ValueError("Attribute 'fps' not set")
else:
return func(clip, *args, **kwargs)
@decorator.decorator
def audio_video_effect(func, effect, clip, *args, **kwargs):
"""Use an audio function on a video/audio clip.
This decorator tells that the function func (audioclip -> audioclip)
can be also used on a video clip, at which case it returns a
videoclip with unmodified video and modified audio.
"""
if hasattr(clip, "audio"):
if clip.audio is not None:
clip.audio = func(effect, clip.audio, *args, **kwargs)
return clip
else:
return func(effect, clip, *args, **kwargs)
[docs]
def preprocess_args(preprocess_func, varnames):
"""Applies preprocess_func to variables in varnames before launching
the function.
"""
def decor(func):
argnames = inspect.getfullargspec(func).args
def wrapper(func, *args, **kwargs):
new_args = [
(
preprocess_func(arg)
if (name in varnames) and (arg is not None)
else arg
)
for (arg, name) in zip(args, argnames)
]
new_kwargs = {
kwarg: preprocess_func(value) if kwarg in varnames else value
for (kwarg, value) in kwargs.items()
}
return func(*new_args, **new_kwargs)
return decorator.decorate(func, wrapper)
return decor
[docs]
def convert_parameter_to_seconds(varnames):
"""Converts the specified variables to seconds."""
return preprocess_args(convert_to_seconds, varnames)
[docs]
def convert_path_to_string(varnames):
"""Converts the specified variables to a path string."""
return preprocess_args(os.fspath, varnames)
@decorator.decorator
def add_mask_if_none(func, clip, *args, **kwargs):
"""Add a mask to the clip if there is none."""
if clip.mask is None:
clip = clip.with_mask()
return func(clip, *args, **kwargs)
[docs]
def use_clip_fps_by_default(func):
"""Will use ``clip.fps`` if no ``fps=...`` is provided in **kwargs**."""
argnames = inspect.getfullargspec(func).args[1:]
def find_fps(clip, fps):
if fps is not None:
return fps
elif getattr(clip, "fps", None):
return clip.fps
raise AttributeError(
"No 'fps' (frames per second) attribute specified"
" for function %s and the clip has no 'fps' attribute. Either"
" provide e.g. fps=24 in the arguments of the function, or define"
" the clip's fps with `clip.fps=24`" % func.__name__
)
def wrapper(func, clip, *args, **kwargs):
new_args = [
find_fps(clip, arg) if name == "fps" else arg
for (arg, name) in zip(args, argnames)
]
new_kwargs = {
kwarg: find_fps(clip, kwarg) if kwarg == "fps" else value
for (kwarg, value) in kwargs.items()
}
return func(clip, *new_args, **new_kwargs)
return decorator.decorate(func, wrapper)
