separate most Quagga module code outside of the static interface to a…

… class - after this commit, there should be no functional change, but the bulk of the code outside the static interface has been moved to a class, instead of global variables. An instance of that class is created at the top as a global.
ericblade · Apr 16, 2020 · b9cade6 · b9cade6
1 parent 73f9762
commit b9cade6
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Showing 8 changed files with 266 additions and 240 deletions.
diff --git a/src/config/config.ts b/src/config/config.ts
@@ -5,6 +5,7 @@ import * as ProdConfig from './config.prod';
 
 declare var ENV: QuaggaBuildEnvironment;
 
+// @ts-ignore // TODO: this produces a bizarre typescript error
 const QuaggaConfig: QuaggaJSConfigObject = ENV.development
     ? DevConfig
     : ENV.node

diff --git a/src/input/camera_access.ts b/src/input/camera_access.ts
@@ -69,7 +69,7 @@ function deprecatedConstraints(videoConstraints: MediaTrackConstraintsWithDeprec
     return normalized;
 }
 
-export function pickConstraints(videoConstraints: MediaTrackConstraintsWithDeprecated): Promise<MediaStreamConstraints> {
+export function pickConstraints(videoConstraints: MediaTrackConstraintsWithDeprecated = {}): Promise<MediaStreamConstraints> {
     const video = deprecatedConstraints(videoConstraints);
 
     if (video && video.deviceId && video.facingMode) {
@@ -95,7 +95,7 @@ function getActiveTrack(): MediaStreamTrack | null {
  * Used for accessing information about the active stream track and available video devices.
  */
 const QuaggaJSCameraAccess = {
-    request: function(video: HTMLVideoElement, videoConstraints: MediaTrackConstraintsWithDeprecated): Promise<any> {
+    request: function(video: HTMLVideoElement, videoConstraints?: MediaTrackConstraintsWithDeprecated): Promise<any> {
         return pickConstraints(videoConstraints)
             .then((newConstraints) => initCamera(video, newConstraints))
             .catch(err => {

diff --git a/src/quagga.js b/src/quagga.js
@@ -1,240 +1,18 @@
 import TypeDefs from './common/typedefs'; // eslint-disable-line no-unused-vars
 import ImageWrapper from './common/image_wrapper';
-import BarcodeLocator from './locator/barcode_locator';
-import BarcodeDecoder from './decoder/barcode_decoder';
 import BarcodeReader from './reader/barcode_reader';
 import Events from './common/events';
 import CameraAccess from './input/camera_access';
 import ImageDebug from './common/image_debug';
 import ResultCollector from './analytics/result_collector';
 import Config from './config/config';
-import BrowserInputStream, { NodeInputStream } from './input/input_stream';
-import BrowserFrameGrabber, { NodeFrameGrabber } from './input/frame_grabber';
 import { merge } from 'lodash';
-import { clone } from 'gl-vec2';
-import { QuaggaContext } from './QuaggaContext';
-
-import setupInputStream from './quagga/setupInputStream.ts';
-import _getViewPort from './quagga/getViewPort.ts';
-import _initBuffers from './quagga/initBuffers.ts';
-import _initCanvas from './quagga/initCanvas';
-import { moveBox, moveLine } from './quagga/transform';
 import * as QWorkers from './quagga/qworker.ts';
 
-const vec2 = { clone };
-
-const InputStream = typeof window === 'undefined' ? NodeInputStream : BrowserInputStream;
-const FrameGrabber = typeof window === 'undefined' ? NodeFrameGrabber : BrowserFrameGrabber;
-
-// export BarcodeReader and other utilities for external plugins
-export { BarcodeReader, BarcodeDecoder, ImageWrapper, ImageDebug, ResultCollector, CameraAccess };
-
-const _context = new QuaggaContext();
-
-function initBuffers(imageWrapper) {
-    const { inputImageWrapper, boxSize } = _initBuffers(_context.inputStream, imageWrapper, _context.config.locator);
-    _context.inputImageWrapper = inputImageWrapper;
-    _context.boxSize = boxSize;
-}
-
-function initializeData(imageWrapper) {
-    initBuffers(imageWrapper);
-    _context.decoder = BarcodeDecoder.create(_context.config.decoder, _context.inputImageWrapper);
-}
-
-function getViewPort() {
-    const { target } = _context.config.inputStream;
-    return _getViewPort(target);
-}
-
-function ready(cb) {
-    _context.inputStream.play();
-    cb();
-}
-
-function initCanvas() {
-    _context.canvasContainer = _initCanvas(_context);
-}
-
-function canRecord(cb) {
-    BarcodeLocator.checkImageConstraints(_context.inputStream, _context.config.locator);
-    initCanvas(_context.config);
-    _context.framegrabber = FrameGrabber.create(_context.inputStream, _context.canvasContainer.dom.image);
-
-    QWorkers.adjustWorkerPool(_context.config.numOfWorkers, _context.config, _context.inputStream, function () {
-        if (_context.config.numOfWorkers === 0) {
-            initializeData();
-        }
-        ready(cb);
-    });
-}
-
-function initInputStream(cb) {
-    const { type: inputType, constraints } = _context.config.inputStream;
-    const { video, inputStream } = setupInputStream(inputType, getViewPort(), InputStream);
-
-    if (inputType === 'LiveStream') {
-        CameraAccess.request(video, constraints)
-            .then(() => inputStream.trigger('canrecord'))
-            .catch((err) => cb(err));
-    }
-
-    inputStream.setAttribute('preload', 'auto');
-    inputStream.setInputStream(_context.config.inputStream);
-    inputStream.addEventListener('canrecord', canRecord.bind(undefined, cb));
-
-    _context.inputStream = inputStream;
-}
-
-function getBoundingBoxes() {
-    if (_context.config.locate) {
-        return BarcodeLocator.locate();
-    } else {
-        return [[
-            vec2.clone(_context.boxSize[0]),
-            vec2.clone(_context.boxSize[1]),
-            vec2.clone(_context.boxSize[2]),
-            vec2.clone(_context.boxSize[3])]];
-    }
-}
-
-function transformResult(result) {
-    const topRight = _context.inputStream.getTopRight();
-    const xOffset = topRight.x;
-    const yOffset = topRight.y;
-
-    if (xOffset === 0 && yOffset === 0) {
-        return;
-    }
-
-    if (result.barcodes) {
-        result.barcodes.forEach((barcode) => transformResult(barcode));
-    }
-
-    if (result.line && result.line.length === 2) {
-        moveLine(result.line, xOffset, yOffset);
-    }
-
-    if (result.box) {
-        moveBox(result.box, xOffset, yOffset);
-    }
-
-    if (result.boxes && result.boxes.length > 0) {
-        for (let i = 0; i < result.boxes.length; i++) {
-            moveBox(result.boxes[i], xOffset, yOffset);
-        }
-    }
-}
-
-function addResult(result, imageData) {
-    if (!imageData || !_context.resultCollector) {
-        return;
-    }
-
-    if (result.barcodes) {
-        result.barcodes.filter(barcode => barcode.codeResult)
-            .forEach(barcode => addResult(barcode, imageData));
-    } else if (result.codeResult) {
-        _context.resultCollector.addResult(imageData, _context.inputStream.getCanvasSize(), result.codeResult);
-    }
-}
-
-function hasCodeResult(result) {
-    return result && (result.barcodes ?
-        result.barcodes.some(barcode => barcode.codeResult) :
-        result.codeResult);
-}
-
-function publishResult(result, imageData) {
-    let resultToPublish = result;
-
-    if (result && _context.onUIThread) {
-        transformResult(result);
-        addResult(result, imageData);
-        resultToPublish = result.barcodes || result;
-    }
-
-    Events.publish('processed', resultToPublish);
-    if (hasCodeResult(result)) {
-        Events.publish('detected', resultToPublish);
-    }
-}
-
-function locateAndDecode() {
-    const boxes = getBoundingBoxes();
-    if (boxes) {
-        const decodeResult = _context.decoder.decodeFromBoundingBoxes(boxes) || {};
-        decodeResult.boxes = boxes;
-        publishResult(decodeResult, _context.inputImageWrapper.data);
-    } else {
-        const imageResult = _context.decoder.decodeFromImage(_context.inputImageWrapper);
-        if (imageResult) {
-            publishResult(imageResult, _context.inputImageWrapper.data);
-        } else {
-            publishResult({ codeResult: { code: null } });
-        }
-    }
-}
-
-function update() {
-    if (_context.onUIThread) {
-        const workersUpdated = QWorkers.updateWorkers(_context.framegrabber);
-        if (!workersUpdated) {
-            _context.framegrabber.attachData(_context.inputImageWrapper.data);
-            if (_context.framegrabber.grab()) {
-                if (!workersUpdated) {
-                    locateAndDecode();
-                }
-            }
-        }
-    } else {
-        _context.framegrabber.attachData(_context.inputImageWrapper.data);
-        _context. _framegrabber.grab();
-        locateAndDecode();
-    }
-}
-
-function startContinuousUpdate() {
-    var next = null,
-        delay = 1000 / (_context.config.frequency || 60);
-
-    _context.stopped = false;
-    (function frame(timestamp) {
-        next = next || timestamp;
-        if (!_context.stopped) {
-            if (timestamp >= next) {
-                next += delay;
-                update();
-            }
-            window.requestAnimFrame(frame);
-        }
-    }(performance.now()));
-}
-
-function start() {
-    if (_context.onUIThread && _context.config.inputStream.type === 'LiveStream') {
-        startContinuousUpdate();
-    } else {
-        update();
-    }
-}
-
-function setReaders(readers) {
-    if (_context.decoder) {
-        _context.decoder.setReaders(readers);
-    }
-    QWorkers.setReaders(readers);
-}
+import Quagga from './quagga/quagga';
 
-function registerReader(name, reader) {
-    // load it to the module
-    BarcodeDecoder.registerReader(name, reader);
-    // then make sure any running instances of decoder and workers know about it
-    if (_context.decoder) {
-        _context.decoder.registerReader(name, reader);
-    }
-    QWorkers.registerReader(name, reader);
-}
+const instance = new Quagga();
+const _context = instance.context;
 
 export default {
     init: function (config, cb, imageWrapper) {
@@ -245,16 +23,16 @@ export default {
         }
         if (imageWrapper) {
             _context.onUIThread = false;
-            initializeData(imageWrapper);
+            instance.initializeData(imageWrapper);
             if (cb) {
                 cb();
             }
         } else {
-            initInputStream(cb);
+            instance.initInputStream(cb);
         }
     },
     start: function () {
-        start();
+        instance.start();
     },
     stop: function () {
         _context.stopped = true;
@@ -280,10 +58,10 @@ export default {
         Events.unsubscribe('processed', callback);
     },
     setReaders: function (readers) {
-        setReaders(readers);
+        instance.setReaders(readers);
     },
     registerReader: function (name, reader) {
-        registerReader(name, reader);
+        instance.registerReader(name, reader);
     },
     registerResultCollector: function (resultCollector) {
         if (resultCollector && typeof resultCollector.addResult === 'function') {
@@ -341,7 +119,7 @@ export default {
                         }
                         resolve(result);
                     }, true);
-                    start();
+                    instance.start();
                 });
             } catch (err) {
                 this.inDecodeSingle = false;

diff --git a/src/quagga/getViewPort.ts b/src/quagga/getViewPort.ts
@@ -1,4 +1,4 @@
-export default function getViewPort(target?: HTMLElement | string) {
+export default function getViewPort(target?: Element | string): Element | null {
     if (typeof document === 'undefined') {
         return null;
     }

diff --git a/src/quagga/initBuffers.ts b/src/quagga/initBuffers.ts
@@ -7,7 +7,7 @@ declare var ENV: QuaggaBuildEnvironment;
 
 // TODO: need typescript def for inputstream
 // TODO: need typescript def for BarcodeLocator
-export default function initBuffers(inputStream: any, imageWrapper: ImageWrapper, locator: any) {
+export default function initBuffers(inputStream: any, imageWrapper: ImageWrapper | undefined, locator: any) {
     const inputImageWrapper = imageWrapper ? imageWrapper : new ImageWrapper({
         x: inputStream.getWidth(),
         y: inputStream.getHeight(),