feat: object locator

src/UseCases/ObjectLocator.ts

@@ -0,0 +1,37 @@
+import PredictedObject from "../Models/PredictedObject"
+import Video from "../Models/Video"
+
+interface Offset {
+  x: number,
+  y: number,
+  hypotenuse: number
+}
+
+class ObjectLocator {
+  private video: Video
+  constructor (video: Video) {
+    this.video = video
+  }
+
+  detectPredictedObjectLocationFromVideo = (predictedObject: PredictedObject): Offset => {
+    const videoCenter = { x: this.video.width / 2, y: this.video.height / 2 }
+    const objectCenter = {
+      x: predictedObject.xOrigin + (predictedObject.width / 2),
+      y: predictedObject.yOrigin + (predictedObject.height / 2)
+    }
+
+
+    const xOffset = videoCenter.x - objectCenter.x
+    const yOffset = videoCenter.y - objectCenter.y
+
+    const objectOffsetFromVideoCenter = {
+      x: xOffset,
+      y: yOffset,
+      hypotenuse: Math.sqrt((xOffset * xOffset) + (yOffset * yOffset))
+    }
+
+    return objectOffsetFromVideoCenter
+  }
+}
+
+export default ObjectLocator

src/app.ts

@@ -2,21 +2,24 @@ import { DetectedObject } from "@tensorflow-models/coco-ssd"
 import PredictedObjectCollectionController from "./Controllers/PredictedObjectCollectionController"
 import VideoController from './Controllers/VideoController'
 import ObjectDetector from './UseCases/ObjectDetector'
+import ObjectLocator from "./UseCases/ObjectLocator"
 
 const defaultPredictions = [
   (prediction: DetectedObject) => prediction.score > 0.6,
-  (prediction: DetectedObject) => prediction.class === 'cat',
+  (prediction: DetectedObject) => prediction.class === 'person', // TODO: change to cat
 ]
 
 class App {
   private predictedObjectCollectionController: PredictedObjectCollectionController
   private videoController: VideoController
   private objectDetector: ObjectDetector
+  private objectLocator: ObjectLocator
 
   constructor () {
     this.objectDetector = new ObjectDetector({ filterPredicates: defaultPredictions })
     this.predictedObjectCollectionController = new PredictedObjectCollectionController()
     this.videoController = new VideoController({  width: 640, height: 480 })
+    this.objectLocator = new ObjectLocator(this.videoController.model)
     this.predictImage()
   }
 
@@ -30,6 +33,11 @@ class App {
 
     const predictedObjects = await this.objectDetector.predictImageStream(imageData)
     this.predictedObjectCollectionController.predictedObjects = predictedObjects
+    const offsets = predictedObjects.map(obj => {
+      return this.objectLocator.detectPredictedObjectLocationFromVideo(obj)
+    })
+
+    console.log(offsets)
 
     window.requestAnimationFrame(this.predictImage)
   }