support segmentation for nodejs

CHANGELOG.md

@@ -11,6 +11,7 @@
   
 ### **HEAD -> main** 2021/09/22 mandic00@live.com
 
+- redo segmentation and handtracking
 - prototype handtracking
 - automated browser tests
 - support for dynamic backend switching

TODO.md

@@ -13,11 +13,6 @@
 
 <br>
 
-### Segmentation
-
-- Implement `NodeJS` support
-- Test for leaks
-
 ### Backends
 
 - Optimize shader packing for WebGL backend:  

demo/index.js

@@ -245,14 +245,14 @@ async function drawResults(input) {
   if (userConfig.segmentation.enabled && ui.buffered) { // refresh segmentation if using buffered output
     const seg = await human.segmentation(input, ui.background);
     if (seg.alpha) {
-      let c = document.getElementById('segmentation-mask');
+      const canvasSegMask = document.getElementById('segmentation-mask');
-      let ctx = c.getContext('2d');
+      const ctxSegMask = canvasSegMask.getContext('2d');
-      ctx.clearRect(0, 0, c.width, c.height); // need to clear as seg.alpha is alpha based canvas so it adds
+      ctxSegMask.clearRect(0, 0, canvasSegMask.width, canvasSegMask.height); // need to clear as seg.alpha is alpha based canvas so it adds
-      ctx.drawImage(seg.alpha, 0, 0, seg.alpha.width, seg.alpha.height, 0, 0, c.width, c.height);
+      ctxSegMask.drawImage(seg.alpha, 0, 0, seg.alpha.width, seg.alpha.height, 0, 0, canvasSegMask.width, canvasSegMask.height);
-      c = document.getElementById('segmentation-canvas');
+      const canvasSegCanvas = document.getElementById('segmentation-canvas');
-      ctx = c.getContext('2d');
+      const ctxSegCanvas = canvasSegCanvas.getContext('2d');
-      ctx.clearRect(0, 0, c.width, c.height); // need to clear as seg.alpha is alpha based canvas so it adds
+      ctxSegCanvas.clearRect(0, 0, canvasSegCanvas.width, canvasSegCanvas.height); // need to clear as seg.alpha is alpha based canvas so it adds
-      ctx.drawImage(seg.canvas, 0, 0, seg.alpha.width, seg.alpha.height, 0, 0, c.width, c.height);
+      ctxSegCanvas.drawImage(seg.canvas, 0, 0, seg.alpha.width, seg.alpha.height, 0, 0, canvasSegCanvas.width, canvasSegCanvas.height);
     }
     // result.canvas = seg.alpha;
   } else if (!result.canvas || ui.buffered) { // refresh with input if using buffered output or if missing canvas

demo/nodejs/node-canvas.js

@@ -21,11 +21,15 @@ const config = { // just enable all and leave default settings
 async function main() {
   log.header();
 
+  globalThis.Canvas = canvas.Canvas; // patch global namespace with canvas library
+  globalThis.ImageData = canvas.ImageData; // patch global namespace with canvas library
+  // human.env.Canvas = canvas.Canvas; // alternatively monkey-patch human to use external canvas library
+  // human.env.ImageData = canvas.ImageData; // alternatively monkey-patch human to use external canvas library
+
   // init
   const human = new Human.Human(config); // create instance of human
   log.info('Human:', human.version);
-  // @ts-ignore
+
-  human.env.Canvas = canvas.Canvas; // monkey-patch human to use external canvas library
   await human.load(); // pre-load models
   log.info('Loaded models:', Object.keys(human.models).filter((a) => human.models[a]));
   log.info('Memory state:', human.tf.engine().memory());
@@ -46,6 +50,10 @@ async function main() {
     // run detection
     const result = await human.detect(inputCanvas);
 
+    // run segmentation
+    // const seg = await human.segmentation(inputCanvas);
+    // log.data('Segmentation:', { data: seg.data.length, alpha: typeof seg.alpha, canvas: typeof seg.canvas });
+
     // print results summary
     const persons = result.persons; // invoke persons getter, only used to print summary on console
     for (let i = 0; i < persons.length; i++) {

src/env.ts

@@ -34,6 +34,7 @@ export type Env = {
   kernels: string[],
   Canvas: undefined,
   Image: undefined,
+  ImageData: undefined,
 }
 
 // eslint-disable-next-line import/no-mutable-exports
@@ -69,6 +70,7 @@ export let env: Env = {
   kernels: [],
   Canvas: undefined,
   Image: undefined,
+  ImageData: undefined,
 };
 
 export async function cpuInfo() {

src/human.ts

@@ -297,7 +297,7 @@ export class Human {
    * @param background?: {@link Input}
    * @returns { data, canvas, alpha }
    */
-  async segmentation(input: Input, background?: Input): Promise<{ data: Uint8ClampedArray | null, canvas: HTMLCanvasElement | OffscreenCanvas | null, alpha: HTMLCanvasElement | OffscreenCanvas | null }> {
+  async segmentation(input: Input, background?: Input): Promise<{ data: number[], canvas: HTMLCanvasElement | OffscreenCanvas | null, alpha: HTMLCanvasElement | OffscreenCanvas | null }> {
     return segmentation.process(input, background, this.config);
   }
 
@@ -441,20 +441,6 @@ export class Human {
       this.performance.image = Math.trunc(now() - timeStamp);
       this.analyze('Get Image:');
 
-      // segmentation is only run explicitly via human.segmentation() which calls segmentation.process()
-      /*
-      if (this.config.segmentation.enabled && process && img.tensor && img.canvas) {
-        this.analyze('Start Segmentation:');
-        this.state = 'detect:segmentation';
-        timeStamp = now();
-        const seg = await segmentation.predict(img, this.config);
-        img = { canvas: seg.canvas, tensor: seg.tensor };
-        elapsedTime = Math.trunc(now() - timeStamp);
-        if (elapsedTime > 0) this.performance.segmentation = elapsedTime;
-        this.analyze('End Segmentation:');
-      }
-      */
-
       if (!img.tensor) {
         if (this.config.debug) log('could not convert input to tensor');
         resolve({ error: 'could not convert input to tensor' });

src/image/image.ts

@@ -30,7 +30,8 @@ export function canvas(width, height): HTMLCanvasElement | OffscreenCanvas {
     }
   } else {
     // @ts-ignore // env.canvas is an external monkey-patch
-    c = (typeof env.Canvas !== 'undefined') ? new env.Canvas(width, height) : null;
+    if (typeof env.Canvas !== 'undefined') c = new env.Canvas(width, height);
+    else if (typeof globalThis.Canvas !== 'undefined') c = new globalThis.Canvas(width, height);
   }
   // if (!c) throw new Error('cannot create canvas');
   return c;
@@ -51,6 +52,7 @@ export function process(input: Input, config: Config): { tensor: Tensor | null,
     !(input instanceof tf.Tensor)
     && !(typeof Image !== 'undefined' && input instanceof Image)
     && !(typeof env.Canvas !== 'undefined' && input instanceof env.Canvas)
+    && !(typeof globalThis.Canvas !== 'undefined' && input instanceof globalThis.Canvas)
     && !(typeof ImageData !== 'undefined' && input instanceof ImageData)
     && !(typeof ImageBitmap !== 'undefined' && input instanceof ImageBitmap)
     && !(typeof HTMLImageElement !== 'undefined' && input instanceof HTMLImageElement)

test/test-main.js

@@ -327,7 +327,8 @@ async function test(Human, inputConfig) {
   ]);
 
   // test monkey-patch
-  human.env.Canvas = canvasJS.Canvas; // monkey-patch human to use external canvas library
+  globalThis.Canvas = canvasJS.Canvas; // monkey-patch to use external canvas library
+  globalThis.ImageData = canvasJS.ImageData; // monkey-patch to use external canvas library
   const inputImage = await canvasJS.loadImage('samples/ai-face.jpg'); // load image using canvas library
   const inputCanvas = new canvasJS.Canvas(inputImage.width, inputImage.height); // create canvas
   const ctx = inputCanvas.getContext('2d');
@@ -338,7 +339,7 @@ async function test(Human, inputConfig) {
 
   // test segmentation
   res = await human.segmentation(inputCanvas, inputCanvas);
-  if (!res || !res.data) log('error', 'failed: segmentation', res);
+  if (!res || !res.data || !res.canvas) log('error', 'failed: segmentation');
   else log('state', 'passed: segmentation', [res.data.length]);
   human.env.Canvas = undefined;
 

test/test-node-wasm.js

@@ -5,9 +5,9 @@ const Human = require('../dist/human.node-wasm.js');
 const test = require('./test-main.js').test;
 
 // @ts-ignore
-Human.env.Canvas = Canvas;
+Human.env.Canvas = Canvas; // requires monkey-patch as wasm does not have tf.browser namespace
 // @ts-ignore
-Human.env.Image = Image;
+Human.env.Image = Image; // requires monkey-patch as wasm does not have tf.browser namespace
 
 const config = {
   // modelBasePath: 'http://localhost:10030/models/',