import { Observable } from 'rxjs';
export declare class ItFileUtils {
    /**
     * Return the file size string
     * @param file the file
     * @param decimals decimal to show
     */
    static getFileSizeString(file: File, decimals?: number): string;
    /**
     * Convert a file to base64 string
     * @param file the base64 string
     */
    static fileToBase64(file: File): Observable<string>;
    /**
     * Convert base64 to Blob
     * @param base64 the base64 string
     * @param mimeType the <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types">MIME type</a> (example 'application/pdf')
     */
    static base64ToBlob(base64: string, mimeType: string): Blob;
    /**
     * Convert base64 to File
     * @param base64 the base64 string
     * @param mimeType the <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types">MIME type</a> (example 'application/pdf')
     * @param filename the file name
     */
    static base64ToFile(base64: string, mimeType: string, filename: string): File;
    /**
     * Extract the MIME type from base64 string
     * @param base64 the base64 string
     */
    static getMimeTypeFromBase64(base64: string): string | undefined;
}