Successfully performing OCR on the captcha image and autofilling it for login.

1 files changed, 43 insertions, 0 deletions

diff --git a/src/offscreen/ocr/index.js b/src/offscreen/ocr/index.js
new file mode 100644
index 0000000..7390bbf
--- /dev/null
+++ b/src/offscreen/ocr/index.js
@@ -0,0 +1,43 @@
+import Tesseract from "./tesseract.esm.min.js";
+
+let ocrWorker = null;
+
+async function performOcrInOffscreen(dataURL) {
+	if (!ocrWorker) {
+		ocrWorker = await Tesseract.createWorker("eng", 1, {
+			workerPath: chrome.runtime.getURL("/offscreen/ocr/worker.min.js"),
+			corePath: chrome.runtime.getURL("/offscreen/ocr"),
+			workerBlobURL: false,
+		});
+
+		await ocrWorker.setParameters({
+			// The only characters that appears
+			tessedit_char_whitelist: "ABCDEFGHJKLMNPQRSTUVWXYZ23456789",
+		});
+	}
+
+	const { data } = await ocrWorker.recognize(dataURL);
+	return data;
+}
+
+// Listen for messages from the Service Worker
+chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
+	if (message.type === "OFFSCREEN_OCR_REQUEST" && message.dataURL) {
+		performOcrInOffscreen(message.dataURL)
+			.then(({ text, confidence }) => {
+				sendResponse({ success: true, text, confidence });
+			})
+			.catch(error => {
+				sendResponse({ success: false, error: error.message });
+			});
+		return true;
+	}
+
+	if (message.type === "OFFSCREEN_TERMINATE_OCR_WORKER") {
+		if (ocrWorker) {
+			ocrWorker.terminate();
+			ocrWorker = null;
+		}
+		sendResponse({ success: true });
+	}
+});