diff --git a/README.md b/README.md
index f9f4c948..8ff7ba16 100644
--- a/README.md
+++ b/README.md
@@ -300,7 +300,7 @@ Default models in Human library are:
 - **Body Analysis**: MoveNet - Lightning variation
 - **Hand Analysis**: MediaPipe Hands
 - **Body Segmentation**: Google Selfie
-- **Object Detection**: CenterNet
+- **Object Detection**: MB3 CenterNet
 - **Body Segmentation**: Google Selfie
 
 Note that alternative models are provided and can be enabled via configuration  
diff --git a/demo/nodejs/node-canvas.js b/demo/nodejs/node-canvas.js
index 8b80c42f..72469477 100644
--- a/demo/nodejs/node-canvas.js
+++ b/demo/nodejs/node-canvas.js
@@ -1,159 +1,68 @@
 /**
- * Human demo for NodeJS
+ * Human demo for NodeJS using Canvas library
  */
 
-const log = require('@vladmandic/pilogger');
 const fs = require('fs');
 const process = require('process');
+const log = require('@vladmandic/pilogger');
 const canvas = require('canvas');
+require('@tensorflow/tfjs-node'); // for nodejs, `tfjs-node` or `tfjs-node-gpu` should be loaded before using Human
+const Human = require('../../dist/human.node.js'); // this is 'const Human = require('../dist/human.node-gpu.js').default;'
 
-// for NodeJS, `tfjs-node` or `tfjs-node-gpu` should be loaded before using Human
-// eslint-disable-next-line no-unused-vars, @typescript-eslint/no-unused-vars
-const tf = require('@tensorflow/tfjs-node'); // or const tf = require('@tensorflow/tfjs-node-gpu');
-
-// load specific version of Human library that matches TensorFlow mode
-const Human = require('../../dist/human.node.js').default; // or const Human = require('../dist/human.node-gpu.js').default;
-
-let human = null;
-
-const myConfig = {
-  backend: 'tensorflow',
-  modelBasePath: 'file://models/',
+const config = { // just enable all and leave default settings
   debug: false,
-  async: true,
-  filter: { enabled: false },
-  face: {
-    enabled: true,
-    detector: { enabled: true },
-    mesh: { enabled: true },
-    iris: { enabled: true },
-    description: { enabled: true },
-    emotion: { enabled: true },
-  },
+  face: { enabled: true }, // includes mesh, iris, emotion, descriptor
   hand: { enabled: true },
   body: { enabled: true },
   object: { enabled: true },
+  gestures: { enabled: true },
 };
 
-async function init() {
-  // create instance of human
-  human = new Human(myConfig);
-  // wait until tf is ready
-  await human.tf.ready();
-  // pre-load models
+async function main() {
+  log.header();
+
+  // init
+  const human = new Human.Human(config); // create instance of human
   log.info('Human:', human.version);
-  await human.load();
-  const loaded = Object.keys(human.models).filter((a) => human.models[a]);
-  log.info('Loaded:', loaded);
+  // @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());
-}
 
-async function detect(input, output) {
-  // read input image from file or url into buffer
-  let buffer;
-  log.info('Loading image:', input);
-  if (input.startsWith('http:') || input.startsWith('https:')) {
-    const fetch = (await import('node-fetch')).default;
-    const res = await fetch(input);
-    if (res && res.ok) buffer = await res.buffer();
-    else log.error('Invalid image URL:', input, res.status, res.statusText, res.headers.get('content-type'));
-  } else {
-    buffer = fs.readFileSync(input);
-  }
-  if (!buffer) return {};
+  // parse cmdline
+  const input = process.argv[2];
+  const output = process.argv[3];
+  if (process.argv.length !== 4) log.error('Parameters: <input-image> <output-image> missing');
+  else if (!fs.existsSync(input) && !input.startsWith('http')) log.error(`File not found: ${process.argv[2]}`);
+  else {
+    // everything seems ok
+    const inputImage = await canvas.loadImage(input); // load image using canvas library
+    log.info('Loaded image', input, inputImage.width, inputImage.height);
+    const inputCanvas = new canvas.Canvas(inputImage.width, inputImage.height); // create canvas
+    const ctx = inputCanvas.getContext('2d');
+    ctx.drawImage(inputImage, 0, 0); // draw input image onto canvas
 
-  // decode image using tfjs-node so we don't need external depenencies
-  /*
-  const tensor = human.tf.tidy(() => {
-    const decode = human.tf.node.decodeImage(buffer, 3);
-    let expand;
-    if (decode.shape[2] === 4) { // input is in rgba format, need to convert to rgb
-      const channels = human.tf.split(decode, 4, 2); // split rgba to channels
-      const rgb = human.tf.stack([channels[0], channels[1], channels[2]], 2); // stack channels back to rgb and ignore alpha
-      expand = human.tf.reshape(rgb, [1, decode.shape[0], decode.shape[1], 3]); // move extra dim from the end of tensor and use it as batch number instead
-    } else {
-      expand = human.tf.expandDims(decode, 0);
-    }
-    const cast = human.tf.cast(expand, 'float32');
-    return cast;
-  });
-  */
+    // run detection
+    const result = await human.detect(inputCanvas);
 
-  // decode image using canvas library
-  const inputImage = await canvas.loadImage(input);
-  const inputCanvas = new canvas.Canvas(inputImage.width, inputImage.height, 'image');
-  const inputCtx = inputCanvas.getContext('2d');
-  inputCtx.drawImage(inputImage, 0, 0);
-  const inputData = inputCtx.getImageData(0, 0, inputImage.width, inputImage.height);
-  const tensor = human.tf.tidy(() => {
-    const data = tf.tensor(Array.from(inputData.data), [inputImage.width, inputImage.height, 4]);
-    const channels = human.tf.split(data, 4, 2); // split rgba to channels
-    const rgb = human.tf.stack([channels[0], channels[1], channels[2]], 2); // stack channels back to rgb and ignore alpha
-    const expand = human.tf.reshape(rgb, [1, data.shape[0], data.shape[1], 3]); // move extra dim from the end of tensor and use it as batch number instead
-    const cast = human.tf.cast(expand, 'float32');
-    return cast;
-  });
-
-  // image shape contains image dimensions and depth
-  log.state('Processing:', tensor['shape']);
-
-  // run actual detection
-  let result;
-  try {
-    result = await human.detect(tensor, myConfig);
-  } catch (err) {
-    log.error('caught');
-  }
-
-  // dispose image tensor as we no longer need it
-  human.tf.dispose(tensor);
-
-  // print data to console
-  if (result) {
-    // invoke persons getter
-    const persons = result.persons;
-    log.data('Detected:');
+    // 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++) {
       const face = persons[i].face;
       const faceTxt = face ? `score:${face.score} age:${face.age} gender:${face.gender} iris:${face.iris}` : null;
       const body = persons[i].body;
       const bodyTxt = body ? `score:${body.score} keypoints:${body.keypoints?.length}` : null;
-      log.data(`  #${i}: Face:${faceTxt} Body:${bodyTxt} LeftHand:${persons[i].hands.left ? 'yes' : 'no'} RightHand:${persons[i].hands.right ? 'yes' : 'no'} Gestures:${persons[i].gestures.length}`);
+      log.data(`Detected: #${i}: Face:${faceTxt} Body:${bodyTxt} LeftHand:${persons[i].hands.left ? 'yes' : 'no'} RightHand:${persons[i].hands.right ? 'yes' : 'no'} Gestures:${persons[i].gestures.length}`);
     }
-  }
 
-  // load and draw original image
-  const outputCanvas = new canvas.Canvas(tensor.shape[2], tensor.shape[1], 'image'); // decoded tensor shape tells us width and height
-  const ctx = outputCanvas.getContext('2d');
-  const original = await canvas.loadImage(buffer); // we already have input as buffer, so lets reuse it
-  ctx.drawImage(original, 0, 0, outputCanvas.width, outputCanvas.height); // draw original to new canvas
-
-  // draw human results on canvas
-  // human.setCanvas(outputCanvas); // tell human to use this canvas
-  human.draw.all(outputCanvas, result); // human will draw results as overlays on canvas
-
-  // write canvas to new image file
-  const out = fs.createWriteStream(output);
-  out.on('finish', () => log.state('Created output image:', output));
-  out.on('error', (err) => log.error('Error creating image:', output, err));
-  const stream = outputCanvas.createJPEGStream({ quality: 0.5, progressive: true, chromaSubsampling: true });
-  stream.pipe(out);
-
-  return result;
-}
-
-async function main() {
-  log.header();
-  log.info('Current folder:', process.env.PWD);
-  await init();
-  const input = process.argv[2];
-  const output = process.argv[3];
-  if (process.argv.length !== 4) {
-    log.error('Parameters: <input-image> <output-image> missing');
-  } else if (!fs.existsSync(input) && !input.startsWith('http')) {
-    log.error(`File not found: ${process.argv[2]}`);
-  } else {
-    await detect(input, output);
+    // draw detected results onto canvas and save it to a file
+    human.draw.all(inputCanvas, result); // use human build-in method to draw results as overlays on canvas
+    const outFile = fs.createWriteStream(output); // write canvas to new image file
+    outFile.on('finish', () => log.state('Output image:', output, inputCanvas.width, inputCanvas.height));
+    outFile.on('error', (err) => log.error('Output error:', output, err));
+    const stream = inputCanvas.createJPEGStream({ quality: 0.5, progressive: true, chromaSubsampling: true });
+    stream.pipe(outFile);
   }
 }
 
diff --git a/src/env.ts b/src/env.ts
index ce7b3d6a..221d8c03 100644
--- a/src/env.ts
+++ b/src/env.ts
@@ -1,4 +1,5 @@
 import * as tf from '../dist/tfjs.esm.js';
+import * as image from './image/image';
 
 export interface Env {
   browser: undefined | boolean,
@@ -9,20 +10,22 @@ export interface Env {
   backends: string[],
   tfjs: {
     version: undefined | string,
-    external: undefined | boolean,
   },
   wasm: {
     supported: undefined | boolean,
+    backend: undefined | boolean,
     simd: undefined | boolean,
     multithread: undefined | boolean,
   },
   webgl: {
     supported: undefined | boolean,
+    backend: undefined | boolean,
     version: undefined | string,
     renderer: undefined | string,
   },
   webgpu: {
     supported: undefined | boolean,
+    backend: undefined | boolean,
     adapter: undefined | string,
   },
   kernels: string[],
@@ -39,20 +42,22 @@ export const env: Env = {
   backends: [],
   tfjs: {
     version: undefined,
-    external: undefined,
   },
   wasm: {
     supported: undefined,
+    backend: undefined,
     simd: undefined,
     multithread: undefined,
   },
   webgl: {
     supported: undefined,
+    backend: undefined,
     version: undefined,
     renderer: undefined,
   },
   webgpu: {
     supported: undefined,
+    backend: undefined,
     adapter: undefined,
   },
   kernels: [],
@@ -60,7 +65,7 @@ export const env: Env = {
   Image: undefined,
 };
 
-export function cpuinfo() {
+export async function cpuInfo() {
   const cpu = { model: '', flags: [] };
   if (env.node && env.platform?.startsWith('linux')) {
     // eslint-disable-next-line global-require
@@ -81,6 +86,37 @@ export function cpuinfo() {
   else env['cpu'] = cpu;
 }
 
+export async function backendInfo() {
+  // analyze backends
+  env.backends = Object.keys(tf.engine().registryFactory);
+  env.wasm.supported = typeof WebAssembly !== 'undefined';
+  env.wasm.backend = env.backends.includes('wasm');
+  if (env.wasm.supported && env.wasm.backend) {
+    env.wasm.simd = await tf.env().getAsync('WASM_HAS_SIMD_SUPPORT');
+    env.wasm.multithread = await tf.env().getAsync('WASM_HAS_MULTITHREAD_SUPPORT');
+  }
+
+  const c = image.canvas(100, 100);
+  const ctx = c ? c.getContext('webgl2') : undefined;
+  env.webgl.supported = typeof ctx !== 'undefined';
+  env.webgl.backend = env.backends.includes('webgl');
+  if (env.webgl.supported && env.webgl.backend) {
+    // @ts-ignore getGPGPUContext only exists on WebGL backend
+    const gl = tf.backend().gpgpu !== 'undefined' ? await tf.backend().getGPGPUContext().gl : null;
+    if (gl) {
+      env.webgl.version = gl.getParameter(gl.VERSION);
+      env.webgl.renderer = gl.getParameter(gl.RENDERER);
+    }
+  }
+
+  env.webgpu.supported = env.browser && typeof navigator['gpu'] !== 'undefined';
+  env.webgpu.backend = env.backends.includes('webgpu');
+  if (env.webgpu.supported) env.webgpu.adapter = (await navigator['gpu'].requestAdapter())?.name;
+
+  // enumerate kernels
+  env.kernels = tf.getKernelsForBackend(tf.getBackend()).map((kernel) => kernel.kernelName.toLowerCase());
+}
+
 export async function get() {
   env.browser = typeof navigator !== 'undefined';
   env.node = typeof process !== 'undefined';
@@ -103,30 +139,8 @@ export async function get() {
     env.agent = `NodeJS ${process.version}`;
   }
 
-  // analyze backends
-  env.backends = Object.keys(tf.engine().registryFactory);
-  env.wasm.supported = env.backends.includes('wasm');
-  if (env.wasm.supported) {
-    env.wasm.simd = await tf.env().getAsync('WASM_HAS_SIMD_SUPPORT');
-    env.wasm.multithread = await tf.env().getAsync('WASM_HAS_MULTITHREAD_SUPPORT');
-  }
-
-  env.webgl.supported = typeof tf.backend().gpgpu !== 'undefined';
-  if (env.webgl.supported) {
-    // @ts-ignore getGPGPUContext only exists on WebGL backend
-    const gl = await tf.backend().getGPGPUContext().gl;
-    if (gl) {
-      env.webgl.version = gl.getParameter(gl.VERSION);
-      env.webgl.renderer = gl.getParameter(gl.RENDERER);
-    }
-  }
-
-  env.webgpu.supported = env.browser && typeof navigator['gpu'] !== 'undefined';
-  if (env.webgpu.supported) env.webgpu.adapter = (await navigator['gpu'].requestAdapter())?.name;
-
-  // enumerate kernels
-  env.kernels = tf.getKernelsForBackend(tf.getBackend()).map((kernel) => kernel.kernelName.toLowerCase());
+  await backendInfo();
 
   // get cpu info
-  // cpuinfo();
+  // await cpuInfo();
 }
diff --git a/src/image/image.ts b/src/image/image.ts
index 3bf26a07..7b6e8353 100644
--- a/src/image/image.ts
+++ b/src/image/image.ts
@@ -29,10 +29,9 @@ export function canvas(width, height) {
     }
   } else {
     // @ts-ignore // env.canvas is an external monkey-patch
-    // eslint-disable-next-line new-cap
     c = (typeof env.Canvas !== 'undefined') ? new env.Canvas(width, height) : null;
   }
-  if (!c) throw new Error('Human: Cannot create canvas');
+  // if (!c) throw new Error('Human: Cannot create canvas');
   return c;
 }
 
@@ -100,7 +99,7 @@ export function process(input: Input, config: Config): { tensor: Tensor | null,
       }
     }
     // imagefx transforms using gl
-    if (config.filter.enabled) {
+    if (config.filter.enabled && env.webgl.supported) {
       if (!fx || !outCanvas || (inCanvas.width !== outCanvas.width) || (inCanvas?.height !== outCanvas?.height)) {
         outCanvas = canvas(inCanvas?.width, inCanvas?.height);
         if (outCanvas?.width !== inCanvas?.width) outCanvas.width = inCanvas?.width;
diff --git a/src/tfjs/humangl.ts b/src/tfjs/humangl.ts
index f5521338..b46e0c54 100644
--- a/src/tfjs/humangl.ts
+++ b/src/tfjs/humangl.ts
@@ -5,6 +5,7 @@
 
 import { log } from '../helpers';
 import * as tf from '../../dist/tfjs.esm.js';
+import * as image from '../image/image';
 
 export const config = {
   name: 'humangl',
@@ -46,13 +47,13 @@ export function register(): void {
   if (!tf.findBackend(config.name)) {
     // log('backend registration:', config.name);
     try {
-      config.canvas = (typeof OffscreenCanvas !== 'undefined') ? new OffscreenCanvas(config.width, config.height) : document.createElement('canvas');
+      config.canvas = image.canvas(100, 100);
     } catch (err) {
       log('error: cannot create canvas:', err);
       return;
     }
     try {
-      config.gl = config.canvas.getContext('webgl2', config.webGLattr) as WebGL2RenderingContext;
+      config.gl = config.canvas?.getContext('webgl2', config.webGLattr) as WebGL2RenderingContext;
     } catch (err) {
       log('error: cannot get WebGL2 context:', err);
       return;
diff --git a/test/test-node-wasm.js b/test/test-node-wasm.js
index c9cc53a3..3472ed8a 100644
--- a/test/test-node-wasm.js
+++ b/test/test-node-wasm.js
@@ -4,7 +4,9 @@ const { Canvas, Image } = require('canvas');
 const Human = require('../dist/human.node-wasm.js');
 const test = require('./test-main.js').test;
 
+// @ts-ignore
 Human.env.Canvas = Canvas;
+// @ts-ignore
 Human.env.Image = Image;
 
 const config = {
diff --git a/wiki b/wiki
index 0e902fcb..44b1bf12 160000
--- a/wiki
+++ b/wiki
@@ -1 +1 @@
-Subproject commit 0e902fcb57bdf9b65ed5e7ef281a699e95db6d99
+Subproject commit 44b1bf12ab5dbf4cedde34da123237b1cd02627b