export declare const SCREENSHOT_MAX_SOURCE_PIXELS = 50000000;
export interface PngDimensions {
    width: number;
    height: number;
}
export declare function hasPngSignature(bytes: Buffer): boolean;
/**
 * Read dimensions from a structurally positioned PNG IHDR without decoding.
 * CRC and complete-file validity remain the decoder's responsibility.
 */
export declare function readPngDeclaredDimensions(bytes: Buffer): PngDimensions | null;