@evocount/react-code-scanner
Version:
A react module for scanning codes like barcodes and QR codes.
136 lines • 7.03 kB
JavaScript
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (_) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
if (t[2]) _.ops.pop();
_.trys.pop(); continue;
}
op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
import "image-capture";
import { MultiFormatReader } from "@zxing/library";
import { NotFoundException } from "@zxing/library";
import { HTMLCanvasElementLuminanceSource } from "@zxing/library";
import { HybridBinarizer } from "@zxing/library";
import { BinaryBitmap } from "@zxing/library";
var Scanner = /** @class */ (function () {
function Scanner(timeout) {
this.timeout = timeout;
this.reader = new MultiFormatReader;
this.canvas = document.createElement("canvas");
}
Scanner.prototype.draw = function (capture) {
return __awaiter(this, void 0, void 0, function () {
var photo, image;
var _this = this;
return __generator(this, function (_a) {
switch (_a.label) {
case 0: return [4 /*yield*/, capture.takePhoto()];
case 1:
photo = _a.sent();
image = new Image();
image.src = URL.createObjectURL(photo);
return [2 /*return*/, new Promise(function (resolve) {
image.onload = function () {
_this.canvas.width = image.width;
_this.canvas.height = image.height;
var context = _this.canvas.getContext("2d");
if (context) {
context.drawImage(image, 0, 0);
resolve();
}
};
})];
}
});
});
};
Scanner.prototype.decode = function (media, callback) {
return __awaiter(this, void 0, void 0, function () {
var track, capture, luminanceSource, hybridBinarizer, bitmap, result, exception_1;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
track = media.getVideoTracks()[0];
capture = new ImageCapture(track);
return [4 /*yield*/, this.draw(capture)];
case 1:
_a.sent();
luminanceSource = new HTMLCanvasElementLuminanceSource(this.canvas);
hybridBinarizer = new HybridBinarizer(luminanceSource);
bitmap = new BinaryBitmap(hybridBinarizer);
_a.label = 2;
case 2:
_a.trys.push([2, 4, , 5]);
result = this.reader.decode(bitmap);
return [4 /*yield*/, callback(result.getText())];
case 3:
_a.sent();
return [3 /*break*/, 5];
case 4:
exception_1 = _a.sent();
if (!(exception_1 instanceof NotFoundException)) {
throw exception_1;
}
return [3 /*break*/, 5];
case 5: return [2 /*return*/];
}
});
});
};
Scanner.prototype.scan = function (cancel, media, callback) {
return __awaiter(this, void 0, void 0, function () {
var _this = this;
return __generator(this, function (_a) {
switch (_a.label) {
case 0: return [4 /*yield*/, cancel.repeat(function () { return __awaiter(_this, void 0, void 0, function () {
return __generator(this, function (_a) {
switch (_a.label) {
case 0: return [4 /*yield*/, this.decode(media, callback)];
case 1:
_a.sent();
return [4 /*yield*/, cancel.timeout(this.timeout)];
case 2:
_a.sent();
return [2 /*return*/];
}
});
}); })];
case 1:
_a.sent();
return [2 /*return*/];
}
});
});
};
return Scanner;
}());
export default Scanner;
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