OPENCV-如何创建具有透明背景的WebM？

Question

当我使用color_rgba2bgr都可以正常工作时，
但是，gif的透明背景成为黑色

示例gif grl： https://i.sstatic.net/wyoqb.gif

当我使用code> color_rgba2bgra 时， opencv 将生成无效的视频。

如何编写具有透明背景的WebM？

转换在这里起作用 https://www.aconvert.com/vide.com/video/gif-to-to-to-to-to-to-to-to--to-to--to--to--to--to--to-to--to--to--to--to--to--to--to-to---------- WebM/ 所以有可能以某种方式

import cv2
import imageio as imageio

fourcc = cv2.VideoWriter_fourcc(*'vp09')
output = cv2.VideoWriter("video.webm", fourcc, 30.0, (512, 500))

frames_ = imageio.mimread("crazy.gif")

# frames = [cv2.cvtColor(frame, cv2.COLOR_RGBA2BGRA) for frame in frames_]
frames = [cv2.cvtColor(frame, cv2.COLOR_RGBA2BGR) for frame in frames_]

for frame in frames:
    frame = cv2.resize(frame, (512, 500))
    output.write(frame)
output.release()