Video Timing & Duration Control | Remove Video Background

// Layer appears at 2 seconds
comp.add(transparent).start(2.0)

// Layer appears immediately (default)
comp.add(transparent).start(0.0)

// Show for exactly 5 seconds
comp.add(transparent).start(2.0).duration(5.0)
// Appears at 2s, disappears at 7s

// Show from 10s to 15s
comp.add(transparent).start(10.0).end(15.0)
// Appears at 10s, disappears at 15s

// Show from start time until end of composition
comp.add(transparent).start(5.0)
// Appears at 5s, continues until composition ends

// Use seconds 5-10 of the source video
const trimmed = transparent.subclip(5, 10)
comp.add(trimmed)

// Use from 3 seconds to end of source
const fromMiddle = transparent.subclip(3)
comp.add(fromMiddle)

// Or trim directly in composition
comp.add(transparent).subclip(2, 8)

// Use seconds 1-4 of source (3 seconds of content)
// Show it at 10-13 seconds in the final video
comp.add(transparent)
  .subclip(1, 4)      // Source: use 1-4s (3s of content)
  .start(10)          // Composition: show at 10s
  .duration(3)        // Composition: show for 3s (10-13s)

const videos = [transparent1, transparent2, transparent3, transparent4]
const positions = [
  Anchor.TOP_LEFT, Anchor.TOP_RIGHT,
  Anchor.BOTTOM_LEFT, Anchor.BOTTOM_RIGHT
]

videos.forEach((vid, i) => {
  comp.add(vid)
    .at(positions[i], 50, 50)
    .size(SizeMode.CANVAS_PERCENT, { percent: 40 })
    .start(i * 2)        // Start every 2 seconds: 0s, 2s, 4s, 6s
    .duration(6)         // Each visible for 6 seconds
    .opacity(0.8)
})

// Layer with full audio
comp.add(transparent1)
  .start(0)
  .audio(true, 1.0)  // Full volume

// Layer with reduced audio
comp.add(transparent2)
  .start(5)
  .audio(true, 0.3)  // 30% volume

// Silent layer
comp.add(transparent3)
  .start(10)
  .audio(false)      // No audio

// 30-second background video = 30-second final composition
const bg = Background.fromVideo('30_second_bg.mp4')
const comp = new Composition(bg)
comp.add(transparent) // Even if foreground is 5 seconds

// Final video will be 30 seconds

// Color background adapts to content
const bg = Background.fromColor('#FF0000', 1920, 1080, 30)
const comp = new Composition(bg)
comp.add(tenSecondTransparent)    // 10-second transparent video
comp.add(fiveSecondTransparent)   // 5-second transparent video

// Final video will be 10 seconds (longest foreground)

const comp = new Composition(anyBackground)
comp.setDuration(20.0) // Force 20-second duration
comp.add(transparent)

// Final video will be exactly 20 seconds

// Method 1: Trim the foreground before adding
const trimmed = video.subclip(10, 20)  // Use seconds 10-20
comp.add(trimmed, 'segment')

// Method 2: Trim in the composition
comp.add(transparent).subclip(10, 20)

// Method 3: Open-ended trim (from 5s to end)
comp.add(transparent).subclip(5)

// Multiple segments from same source
comp.add(transparent).subclip(0, 3).start(0)      // 0-3s of source at 0s
comp.add(transparent).subclip(10, 15).start(5)   // 10-15s of source at 5s
comp.add(transparent).subclip(25, 30).start(12)   // 25-30s of source at 12s

// Re-trimming (trim a trimmed video)
const firstTrim = transparent.subclip(5, 20)    // 5-20s of original
const secondTrim = firstTrim.subclip(2, 8) // 2-8s of first trim = 7-13s of original

// Transparent video with audio that starts at 3 seconds
comp.add(transparent)
  .start(3.0)
  .audio(true, 1.0)  // Audio automatically delayed to match video

// Multiple audio sources with different timing
comp.add(transparent1).start(0).audio(true, 0.8)   // Main audio
comp.add(transparent2).start(5).audio(true, 0.3)      // Background music
comp.add(transparent3).start(10).audio(true, 0.5)   // Sound effects