How to create comparison video for two videos with ffmpeg

• simplest with hstack (1)
• simplest with hstack (2)
• simplest with vstack (1)
• simplest with vstack (2)
• Using crop, and hstack (or vstack)
• Using `alphamerge’
  • using a non-rectangular division
    • Example 1
    • Example 2
  • swapping two videos sequentially
    • Example 1
    • Example 2
    • Example 3
    • Example 4
    • Example 5
• simplest with overlay
• overlapping (insufficient)
• _expr of blend (complex, and slow)
• Using pad, overlay and blend … (1)
• Using pad, overlay and blend … (2)
• Using pad, overlay and blend … (3)
• Showing pixel value difference between two video streams
  • Show differences as values
  • Emphasize whether there is a difference
• Showing the difference by lining up multiple frames at once