Added automatic detection of simd support (#641)

package-lock.json

@@ -21,6 +21,7 @@
         "regenerator-runtime": "^0.13.3",
         "resolve-url": "^0.2.1",
         "tesseract.js-core": "^3.0.1",
+        "wasm-feature-detect": "^1.2.11",
         "zlibjs": "^0.3.1"
       },
       "devDependencies": {
@@ -8740,6 +8741,11 @@
         "node": ">=4.0.0"
       }
     },
+    "node_modules/wasm-feature-detect": {
+      "version": "1.2.11",
+      "resolved": "https://registry.npmjs.org/wasm-feature-detect/-/wasm-feature-detect-1.2.11.tgz",
+      "integrity": "sha512-HUqwaodrQGaZgz1lZaNioIkog9tkeEJjrM3eq4aUL04whXOVDRc/o2EGb/8kV0QX411iAYWEqq7fMBmJ6dKS6w=="
+    },
     "node_modules/watchpack": {
       "version": "2.4.0",
       "resolved": "https://registry.npmjs.org/watchpack/-/watchpack-2.4.0.tgz",
@@ -16052,6 +16058,11 @@
         "rx": "^4.1.0"
       }
     },
+    "wasm-feature-detect": {
+      "version": "1.2.11",
+      "resolved": "https://registry.npmjs.org/wasm-feature-detect/-/wasm-feature-detect-1.2.11.tgz",
+      "integrity": "sha512-HUqwaodrQGaZgz1lZaNioIkog9tkeEJjrM3eq4aUL04whXOVDRc/o2EGb/8kV0QX411iAYWEqq7fMBmJ6dKS6w=="
+    },
     "watchpack": {
       "version": "2.4.0",
       "resolved": "https://registry.npmjs.org/watchpack/-/watchpack-2.4.0.tgz",

package.json

@@ -69,6 +69,7 @@
     "regenerator-runtime": "^0.13.3",
     "resolve-url": "^0.2.1",
     "tesseract.js-core": "^3.0.1",
+    "wasm-feature-detect": "^1.2.11",
     "zlibjs": "^0.3.1"
   },
   "repository": {

src/worker-script/browser/getCore.js

@@ -1,15 +1,26 @@
-module.exports = (corePath, res) => {
+const { simd } = require('wasm-feature-detect');
+const { dependencies } = require('../../../package.json');
+
+module.exports = async (corePath, res) => {
   if (typeof global.TesseractCore === 'undefined') {
     res.progress({ status: 'loading tesseract core', progress: 0 });
-    global.importScripts(corePath);
-    /*
-     * Depending on whether the browser supports WebAssembly,
-     * the version of the TesseractCore will be different.
-     */
+
+    // If the user specifies a core path, we use that
+    // Otherwise, we detect the correct core based on SIMD support
+    let corePathImport = corePath;
+    if (!corePathImport) {
+      const simdSupport = await simd();
+      if (simdSupport) {
+        corePathImport = `https://unpkg.com/tesseract.js-core@v${dependencies['tesseract.js-core'].substring(1)}/tesseract-core.wasm.js`;
+      } else {
+        corePathImport = `https://unpkg.com/tesseract.js-core@v${dependencies['tesseract.js-core'].substring(1)}/tesseract-core-simd.wasm.js`;
+      }
+    }
+
+    global.importScripts(corePathImport);
+
     if (typeof global.TesseractCoreWASM !== 'undefined' && typeof WebAssembly === 'object') {
       global.TesseractCore = global.TesseractCoreWASM;
-    } else if (typeof global.TesseractCoreASM !== 'undefined') {
-      global.TesseractCore = global.TesseractCoreASM;
     } else {
       throw Error('Failed to load TesseractCore');
     }

src/worker-script/index.js

@@ -28,10 +28,10 @@ let latestJob;
 let adapter = {};
 let params = defaultParams;
 
-const load = ({ workerId, jobId, payload: { options: { corePath, logging } } }, res) => {
+const load = async ({ workerId, jobId, payload: { options: { corePath, logging } } }, res) => {
   setLogging(logging);
   if (!TessModule) {
-    const Core = adapter.getCore(corePath, res);
+    const Core = await adapter.getCore(corePath, res);
 
     res.progress({ workerId, status: 'initializing tesseract', progress: 0 });
 

src/worker-script/node/getCore.js

@@ -1,12 +1,19 @@
+const { simd } = require('wasm-feature-detect');
+
 let TesseractCore = null;
 /*
  * getCore is a sync function to load and return
  * TesseractCore.
  */
-module.exports = (_, res) => {
+module.exports = async (_, res) => {
   if (TesseractCore === null) {
+    const simdSupport = await simd();
     res.progress({ status: 'loading tesseract core', progress: 0 });
-    TesseractCore = require('tesseract.js-core');
+    if (simdSupport) {
+      TesseractCore = require('tesseract.js-core/tesseract-core-simd');
+    } else {
+      TesseractCore = require('tesseract.js-core/tesseract-core');
+    }
     res.progress({ status: 'loaded tesseract core', progress: 1 });
   }
   return TesseractCore;

src/worker-script/utils/setImage.js

@@ -20,9 +20,9 @@ module.exports = (TessModule, api, image) => {
   const exif = buf.slice(0, 500).toString().match(/\x01\x12\x00\x03\x00\x00\x00\x01\x00(.)/)?.[1]?.charCodeAt(0) || 1;
 
   /*
-   * Although leptonica should support reading bmp, there is a bug of "compressed BMP files".
-   * As there is no solution, we need to use bmp-js for now.
-   * @see https://groups.google.com/forum/#!topic/tesseract-ocr/4mPD9zTxdxE
+   * Leptonica supports uncompressed but not compressed bmp files
+   * @see https://github.com/DanBloomberg/leptonica/issues/607#issuecomment-1068802516
+   * We therefore use bmp-js to process all bmp files
    */
   if (type && type.mime === 'image/bmp') {
     const bmpBuf = bmp.decode(buf);

src/worker/browser/defaultOptions.js

@@ -1,5 +1,5 @@
 const resolveURL = require('resolve-url');
-const { version, dependencies } = require('../../../package.json');
+const { version } = require('../../../package.json');
 const defaultOptions = require('../../constants/defaultOptions');
 
 /*
@@ -14,5 +14,5 @@ module.exports = {
    * If browser doesn't support WebAssembly,
    * load ASM version instead
    */
-  corePath: `https://unpkg.com/tesseract.js-core@v${dependencies['tesseract.js-core'].substring(1)}/tesseract-core.${typeof WebAssembly === 'object' ? 'wasm' : 'asm'}.js`,
+  corePath: null,
 };