UnsatisfiedLinkError: Could not load library: gstreamer

[chestic3211]

import processing.video.*;

Capture cam;

void setup() {
size(640, 480);

String[] cameras = Capture.list();

if (cameras.length == 0) {
println("There are no cameras available for capture.");
exit();
} else {
println("Available cameras:");
for (int i = 0; i < cameras.length; i++) {
println(cameras[i]);
}

cam = new Capture(this, cameras[0]);
cam.start();     

}
}

void draw() {
if (cam.available() == true) {
cam.read();
}
image(cam, 0, 0);
}

Environment
Win10
Processing 4.0b2

It keeps saying error and I can't understand why?