import type { InferenceSession } from "onnxruntime-common";
import type { PaddleOptions, RecognizeOptions } from "../interface.js";
import { BaseDetectionService } from "./base-detection.service.js";
import { BaseRecognitionService, type RecognitionResult } from "./base-recognition.service.js";
import type { CoreCanvas, PlatformProvider } from "./platform.js";
/**
 * OCR result grouped by detected text lines.
 *
 * Each entry in `lines` is an array of recognized words on the same line,
 * sorted left-to-right.
 */
export interface PaddleOcrResult {
    /** Full extracted text with lines separated by newlines. */
    text: string;
    /** Recognition results grouped by line, in reading order. */
    lines: RecognitionResult[][];
    /** Average confidence across all recognized items (0–1). */
    confidence: number;
}
/**
 * OCR result as a flat list of recognized text items.
 *
 * Convenience alternative to {@link PaddleOcrResult} when line grouping
 * is not needed (e.g. for search indexing or simple display).
 */
export interface FlattenedPaddleOcrResult {
    /** Full extracted text as a single space-separated string. */
    text: string;
    /** All recognized items in reading order. */
    results: RecognitionResult[];
    /** Average confidence across all recognized items (0–1). */
    confidence: number;
}
/** Base URL for downloading default PaddleOCR model files from GitHub. */
export declare const MODEL_BASE_URL = "https://media.githubusercontent.com/media/PT-Perkasa-Pilar-Utama/ppu-paddle-ocr-models/main";
/** Base URL for downloading default PaddleOCR dictionary files from GitHub. */
export declare const DICT_BASE_URL = "https://raw.githubusercontent.com/PT-Perkasa-Pilar-Utama/ppu-paddle-ocr-models/main";
/**
 * Abstract base class for platform-agnostic PaddleOCR service.
 *
 * Concrete implementations (`PaddleOcrService` for Node, Web, etc.)
 * extend this class and provide a {@link PlatformProvider}.
 */
export declare abstract class BasePaddleOcrService {
    protected options: PaddleOptions;
    protected detectionSession: InferenceSession | null;
    protected recognitionSession: InferenceSession | null;
    protected detector: BaseDetectionService | null;
    protected recognitor: BaseRecognitionService | null;
    protected readonly platform: PlatformProvider;
    constructor(platform: PlatformProvider, options?: PaddleOptions);
    protected log(message: string): void;
    protected abstract initSessions(): Promise<void>;
    /**
     * Run the full OCR pipeline (detection → recognition) on an image.
     *
     * @param image - The source image as an `ArrayBuffer`, platform canvas, or URL/path string.
     * @param options - Per-call options such as `flatten`, `noCache`, and custom `dictionary`.
     * @returns Grouped or flattened OCR results depending on `options.flatten`.
     */
    recognize(image: ArrayBuffer | CoreCanvas | string, options?: RecognizeOptions): Promise<PaddleOcrResult | FlattenedPaddleOcrResult>;
    private flattenResults;
    private groupResultsByLine;
}