[video inclusion in Manim] Include video objects picture-in-picture. #manim #animate #video #opencv #videomobject

20240309_opencv.py

import cv2 # needs opencv-python https://pypi.org/project/opencv-python/
from PIL import Image, ImageOps
from dataclasses import dataclass

@dataclass
class VideoStatus:
    time: float = 0
    videoObject: cv2.VideoCapture = None
    def __deepcopy__(self, memo):
        return self

class VideoMobject(ImageMobject):
    '''
    Following a discussion on Discord about animated GIF images.
    Modified for videos

    Parameters
    ----------
    filename
        the filename of the video file

    imageops
        (optional) possibility to include a PIL.ImageOps operation, e.g.
        PIL.ImageOps.mirror

    speed
        (optional) speed-up/slow-down the playback

    loop
        (optional) replay the video from the start in an endless loop

    https://discord.com/channels/581738731934056449/1126245755607339250/1126245755607339250
    2023-07-06 Uwe Zimmermann & Abulafia
    2024-03-09 Uwe Zimmermann
    '''
    def __init__(self, filename=None, imageops=None, speed=1.0, loop=False, **kwargs):
        self.filename = filename
        self.imageops = imageops
        self.speed    = speed
        self.loop     = loop
        self._id = id(self)
        self.status = VideoStatus()
        self.status.videoObject = cv2.VideoCapture(filename)

        self.status.videoObject.set(cv2.CAP_PROP_POS_FRAMES, 1)
        ret, frame = self.status.videoObject.read()
        if ret:
            frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)            
            img = Image.fromarray(frame)

            if imageops != None:
                img = imageops(img)
        else:
            img = Image.fromarray(np.uint8([[63, 0, 0, 0],
                                        [0, 127, 0, 0],
                                        [0, 0, 191, 0],
                                        [0, 0, 0, 255]
                                        ]))
        super().__init__(img, **kwargs)
        if ret:
            self.add_updater(self.videoUpdater)

    def videoUpdater(self, mobj, dt):
        if dt == 0:
            return
        status = self.status
        status.time += 1000*dt*mobj.speed
        self.status.videoObject.set(cv2.CAP_PROP_POS_MSEC, status.time)
        ret, frame = self.status.videoObject.read()
        if (ret == False) and self.loop:
            status.time = 0
            self.status.videoObject.set(cv2.CAP_PROP_POS_MSEC, status.time)
            ret, frame = self.status.videoObject.read()
        if ret:
            frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)  # needed here?        
            img = Image.fromarray(frame)

            if mobj.imageops != None:
                img = mobj.imageops(img)
            mobj.pixel_array = change_to_rgba_array(
                np.asarray(img), mobj.pixel_array_dtype
            )

class test(Scene):
    def construct(self):
        video1 = VideoMobject(
            filename=r"D:\Programming\Python\manim\discord\media\videos\20240304_01\480p15\Countdown.mp4",
            speed=1.0
        ).scale_to_fit_width(5).to_corner(UL)
        video2 = VideoMobject(
            filename=r"D:\Programming\Python\manim\discord\media\videos\20240304_01\480p15\Countdown.mp4",
            speed=3.0,
            loop=True,
            imageops=ImageOps.mirror
        ).scale_to_fit_width(5).to_corner(UR)
        v1 = Group(video1, SurroundingRectangle(video1))
        v2 = Group(video2, SurroundingRectangle(video2))
        self.add(v1,v2)
        self.wait(2)
        self.play(v2.animate.shift(3*DL), run_time=6)
        self.wait(2)

readme.md

How to play a GIF with alpha channel? I have no experience with OpenCV and I am a newbie in Manim.

For GIF images I have another code using PIL rather than OpenCV:
https://gist.github.com/uwezi/87a65edf71adbe7a6767a67f01434625/revisions
it should handle transparent GIF images just find.

Even though my individual GISTs don't have individual licenses attached you can see all my stuff on Github as MIT licensed
https://github.com/uwezi/manim-related?tab=MIT-1-ov-file#readme