import type { InferenceSession } from "onnxruntime-common";
import type { BatchRecognizeOptions, PaddleOptions, RecognizeOptions } from "../interface.js";
import type { BaseDetectionService } from "./base-detection.service.js";
import type { BaseRecognitionService, RecognitionResult } from "./base-recognition.service.js";
import type { BatchItemResult } from "./batch.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 type 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 type 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;
};
/** A single OCR result, grouped or flattened depending on `flatten`. */
export type AnyOcrResult = PaddleOcrResult | FlattenedPaddleOcrResult;
/** Accepted source for a single image in a batch. */
export type BatchRecognizeInput = ArrayBuffer | CoreCanvas | string;
/**
 * 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>;
    /**
     * Run {@link recognize} over many images with bounded concurrency.
     *
     * Results are returned index-aligned to the inputs regardless of completion
     * order. Memory stays bounded: at most `concurrency` images are decoded and
     * in flight at once, so a large (or streamed) input set never materializes
     * all at once. See {@link BatchRecognizeOptions} for `settle`, `signal`, and
     * `onProgress`.
     *
     * @param images - An array or (async) iterable of image sources.
     * @param options - Per-image recognize options plus batch controls.
     */
    batchRecognize(images: Iterable<BatchRecognizeInput> | AsyncIterable<BatchRecognizeInput>, options: BatchRecognizeOptions & {
        settle: true;
    }): Promise<BatchItemResult<AnyOcrResult>[]>;
    batchRecognize(images: Iterable<BatchRecognizeInput> | AsyncIterable<BatchRecognizeInput>, options?: BatchRecognizeOptions): Promise<AnyOcrResult[]>;
    /**
     * Streaming variant of {@link batchRecognize}: yields each image's result as
     * soon as it finishes (completion order), so callers needn't buffer the whole
     * batch. Each item carries its input `index` for reordering.
     *
     * With `settle: false` (default) the generator throws on the first image
     * failure; with `settle: true` failures arrive as `{ status: "rejected" }`.
     */
    batchRecognizeStream(images: Iterable<BatchRecognizeInput> | AsyncIterable<BatchRecognizeInput>, options?: BatchRecognizeOptions): AsyncGenerator<BatchItemResult<AnyOcrResult>>;
    /**
     * Resolve the effective concurrency. `"auto"` (or unset) yields `1` when an
     * accelerator execution provider is configured, else a small CPU default.
     */
    private resolveConcurrency;
    private flattenResults;
    private groupResultsByLine;
}