export declare const labelx264Preset: (profile: "fast" | "faster" | "medium" | "placebo" | "slow" | "slower" | "superfast" | "ultrafast" | "veryfast" | "veryslow") => "fast" | "faster" | "medium" | "placebo" | "slow" | "slower" | "superfast" | "ultrafast" | "veryfast" | "veryslow";