export declare class File { private static isURL; private static isPDF; static readFile(path: string): NonSharedBuffer; static readURL(url: string): Promise>; private static bufferChecksum; static bufferToBase64(buffer: Buffer): string; static fromBufferToHash(buffer: Buffer): string; static fromLocalToBuffer(path: string): NonSharedBuffer; static fromLocal(path: string): { base64: string; checksum: string; }; static fromLocalToHash(path: string): string; static fromRemoteToBuffer(url: string): Promise>; static fromRemote(url: string): Promise<{ base64: string; checksum: string; }>; static fromRemoteToHash(url: string): Promise; static base64ToBuffer(base64: string): Buffer; static bufferToDisk(filename: string, buffer: Buffer): void; static base64ToDisk(filename: string, base64: string): void; }