added tesseract package, trying to recognize text from base64 image

src/utils/tesseract.ts

@@ -0,0 +1,53 @@
+import {
+  createWorker,
+  Worker as TesseractWorker,
+  ConfigResult,
+} from 'tesseract.js'
+
+import logger from './logger'
+import { isMainThread, workerData } from 'worker_threads'
+
+// https://github.com/naptha/tesseract.js/blob/master/docs/api.md
+let tesseractWorker: TesseractWorker = null
+export async function initTesseractWorker(): Promise<TesseractWorker> {
+  const worker = createWorker({
+    cacheMethod: 'refresh',
+    // logger: (m) => console.log(m),
+  })
+  await worker.load()
+  await worker.loadLanguage('hun+eng')
+  await worker.initialize('hun+eng')
+  return worker
+  // await worker.terminate();
+}
+
+let resolveLoaded: () => void = null
+export const tesseractLoaded: Promise<void> = new Promise((resolve) => {
+  resolveLoaded = resolve
+})
+
+initTesseractWorker().then((worker) => {
+  tesseractWorker = worker
+
+  if (isMainThread) {
+    logger.Log('Tesseract loaded on main thread')
+  } else {
+    const { workerIndex }: { workerIndex: number } = workerData
+    logger.Log(`[THREAD #${workerIndex}]: Tesseract loaded`)
+  }
+  resolveLoaded()
+})
+
+export async function recognizeTextFromBase64(base64: string): Promise<string> {
+  const {
+    data: { text },
+  } = await tesseractWorker.recognize(base64)
+  return text
+}
+
+export async function terminateWorker(): Promise<void | ConfigResult> {
+  if (tesseractWorker) {
+    return tesseractWorker.terminate()
+  }
+  return
+}