Avisynth+: how to fade out an overlay image to transparency?

[elektro]

I don't need fade to black or white but fade out to transparency (basically the overlay image to gradually disappear). Can anyone help me with a working script?

[jagabo]

The Animate() filter lets you vary settings over a number of frames. You can use that along with Overlay().

function MyOverlay(clip v1, clip v2, float alpha) # overlay v2, onto v1, with the given transparency
{
    Overlay(v1, v2, opacity=alpha) # overlay v2, onto v1 with specified opacity
}

# create a couple video streams
background = ColorBars(pixel_type="YV12")
foreground = BilinearResize(background, background.width/2, background.height/2)

# fade out over frames 0 to 30
Animate(0, 30, "MyOverlay",    background, foreground, 1.0,    background, foreground, 0.0)

[elektro]

The Animate() filter lets you vary settings over a number of frames. You can use that along with Overlay().

function MyOverlay(clip v1, clip v2, float alpha) # overlay v2, onto v1, with the given transparency
{
    Overlay(v1, v2, opacity=alpha) # overlay v2, onto v1 with specified opacity
}

# create a couple video streams
background = ColorBars(pixel_type="YV12")
foreground = BilinearResize(background, background.width/2, background.height/2)

# fade out over frames 0 to 30
Animate(0, 30, "MyOverlay",    background, foreground, 1.0,    background, foreground, 0.0)

Thanks, it worked! For future reference, I adapted this script to set the x and y coordinates of the overlay:

function OverlayImage(clip v1, clip v2, int x, int y, float alpha) # overlay v2, onto v1, with the given transparency
{
    Overlay(v1, v2, x, y, opacity=alpha) # overlay v2, onto v1 at x, y coordinates with specified opacity
}

img=ImageSource("overlay.png")
Animate(0, 10, "OverlayImage", last, img, 500, 420, 1.0, last, img, 500, 420, 0.0)