If you don't have Photoshop, or want a one-click solution:
Transparency Handling: Excellent at maintaining the transparency of objects like shadows or smoke.
Adobe has integrated these masking capabilities directly into Photoshop: knockout photoshop plugin free download full
It is considered legacy software and was originally released for systems like Windows XP and Mac OS X (versions 8.6 to 9.1). Availability:
If you really want the old Knockout for nostalgia or legacy projects, check the Internet Archive or oldversion.com, but expect compatibility issues on Windows 10/11 or macOS. Alternative 2: Remove
that performs the same complex masking and transparency tasks as the old plugin. Deep Knockout
Corel KnockOut 2 was specifically designed to handle "impossible" masks. It uses a unique "transition area" method where you define the foreground, background, and the fuzzy edges (like flyaway hair) for high-precision extraction. Note on Availability: that performs the same complex masking and transparency
Remove.bg: A popular AI-based web tool that handles the "knockout" process automatically in seconds.