faceclaw/app/native/image-files.ts at main · hmmhmmhm/faceclaw

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10 6D92

/**

* Image-file decoding for the on-glasses image viewer, backed by the Java

* ImageFileLoader (BitmapFactory handles PNG/JPEG/GIF/BMP/WebP/HEIC).

import { GrayImage } from "../graphics/image";

import { toUint8Array } from "../util/array-util";

declare const com: any;

declare const global: any;

/** File extensions BitmapFactory can decode (no SVG). */

export function isDecodableImageFile(name: string): boolean {

return DECODABLE_IMAGE.test(name);

}

/**

* Decode a gray packet ([widthLo, widthHi, heightLo, heightHi, pixels...],

* the format the Java helpers return) into a GrayImage; null when empty or

* malformed.

export function grayImageFromPacket(raw: ArrayLike<number> | null | undefined): GrayImage | null {

const bytes = toUint8Array(raw);

if (bytes.length < 4) return null;

const width = bytes[0]! | (bytes[1]! << 8);

const height = bytes[2]! | (bytes[3]! << 8);

if (width <= 0 || height <= 0 || bytes.length < 4 + width * height) return null;

const image = new GrayImage(width, height, 0);

image.pixels.set(bytes.subarray(4, 4 + width * height));

return image;

}

/**

* Load an image file as grayscale, downscaled to fit maxWidth x maxHeight

* (aspect preserved, never upscaled); null when unreadable or undecodable.

export function loadImageFileAsGray(path: string, maxWidth: number, maxHeight: number): GrayImage | null {

if (!global.isAndroid) return null;

try {

return grayImageFromPacket(

com.faceclaw.app.ImageFileLoader.loadGray(path, Math.round(maxWidth), Math.round(maxHeight)),

);

} catch (error) {

console.warn(`loadImageFileAsGray failed for ${path}: ${error}`);

return null;

}