overlay

Overlay Foreground onto Background

Description

Composite a PNG (with alpha) or video over a background video or image using FFmpeg’s overlay filter.

Usage

overlay(background, foreground, output, x = 0, y = 0, scale = NULL,
        shortest = TRUE, overwrite = TRUE, dry_run = FALSE)

Arguments

  • background: Path to background video or image.
  • foreground: Path to foreground video or PNG (alpha supported).
  • output: Path for output video file.
  • x: Horizontal offset for overlay placement (default 0).
  • y: Vertical offset for overlay placement (default 0).
  • scale: Optional scale string for the foreground (e.g. “320:240” or “iw/2:ih/2”).
  • shortest: If TRUE (default), end output when the shortest input ends.
  • overwrite: If TRUE (default), overwrite output file.
  • dry_run: If TRUE, return the FFmpeg command without executing.

Value

Invisibly returns the output path. If dry_run, returns command string.

Examples

overlay("bg.mp4", "character.png", "out.mp4", x = 312, y = 580)
overlay("bg.mp4", "logo.png", "out.mp4", x = 10, y = 10, scale = "100:100")