/**
 * Language utilities for normalizing language codes across different formats
 */
/**
 * Standardized language information across all TTS engines
 */
export interface StandardizedLanguage {
    /**
     * ISO 639-3 language code (3-letter)
     */
    iso639_3: string;
    /**
     * BCP-47 language tag
     */
    bcp47: string;
    /**
     * Human-readable display name
     */
    display: string;
    /**
     * Country/region code (if applicable)
     */
    countryCode?: string;
}
/**
 * Language normalization utilities
 */
export declare class LanguageNormalizer {
    /**
     * Common language display names
     */
    private static readonly languageNames;
    /**
     * Common region display names
     */
    private static readonly regionNames;
    /**
     * ISO 639-1 to ISO 639-3 mapping
     */
    private static readonly iso1To3;
    /**
     * Normalize a language code to standard formats
     * @param langCode Input language code (can be ISO639-1/2/3, BCP47, or locale)
     * @param countryCode Optional country code to help with regionalization
     * @returns StandardizedLanguage object containing normalized codes
     */
    static normalize(langCode: string, countryCode?: string): StandardizedLanguage;
    /**
     * Get the display name for a language code
     * @param langCode Language code
     * @returns Display name
     */
    static getDisplayName(langCode: string): string;
    /**
     * Get the ISO 639-3 code for a language code
     * @param langCode Language code
     * @returns ISO 639-3 code
     */
    static getISO639_3(langCode: string): string;
    /**
     * Get the BCP-47 tag for a language code
     * @param langCode Language code
     * @param countryCode Optional country code
     * @returns BCP-47 tag
     */
    static getBCP47(langCode: string, countryCode?: string): string;
}