import type { EasingType } from '@visactor/vrender-core';
import { HybridEffectBase } from './base/CustomEffectBase';
export interface ColorEffectConfig {
    effectType: 'grayscale' | 'sepia';
    strength: number;
    useWebGL: boolean;
}
export declare class Grayscale extends HybridEffectBase {
    private colorConfig;
    constructor(from: null, to: null, duration: number, easing: EasingType, params: any);
    protected getShaderSources(): {
        vertex: string;
        fragment: string;
    } | null;
    protected applyWebGLEffect(canvas: HTMLCanvasElement): HTMLCanvasElement | null;
    private setColorUniforms;
    protected applyCanvas2DEffect(canvas: HTMLCanvasElement): HTMLCanvasElement | null;
    private canUseCSSFilter;
    private applyCSSFilter;
    private applyGrayscaleEffect;
    private applySepiaEffect;
    protected afterStageRender(stage: any, canvas: HTMLCanvasElement): HTMLCanvasElement | void | null | false;
}