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Error: When running in node, pixels must be an HTMLCanvasElement like the one returned by the `canvas` npm package

See original GitHub issue

To get help from the community, we encourage using Stack Overflow and the tensorflow.js tag.

TensorFlow.js version

latest version in package.json

Browser version

node.js

Describe the problem or feature request

I get this error whe calling tf.browser.fromPixels

Code to reproduce the bug / link to feature request

const tf = require('@tensorflow/tfjs');
require('@tensorflow/tfjs-node');
//...
img = tf.browser.fromPixels(img);

Full stacktrace:

(node:48448) UnhandledPromiseRejectionWarning: Error: When running in node, pixels must be an HTMLCanvasElement like the one returned by the `canvas` npm package
    at NodeJSKernelBackend.fromPixels (/Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/node_modules/@tensorflow/tfjs-node/dist/nodejs_kernel_backend.js:1306:19)
    at Engine.fromPixels (/Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/node_modules/@tensorflow/tfjs-core/dist/engine.js:498:29)
    at fromPixels_ (/Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/node_modules/@tensorflow/tfjs-core/dist/ops/browser.js:83:37)
    at Object.fromPixels (/Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/node_modules/@tensorflow/tfjs-core/dist/ops/operation.js:46:29)
    at /Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/lib/index.js:112:34
    at /Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/node_modules/@tensorflow/tfjs-core/dist/engine.js:114:22
    at Engine.scopedRun (/Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/node_modules/@tensorflow/tfjs-core/dist/engine.js:124:23)
    at Engine.tidy (/Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/node_modules/@tensorflow/tfjs-core/dist/engine.js:113:21)
    at Object.Environment.tidy (/Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/node_modules/@tensorflow/tfjs-core/dist/environment.js:170:35)
    at NSFWJS.infer (/Users/loretoparisi/Documents/Projects/AI/nsfwjs-node/lib/index.js:110:19)
(node:48448) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 2)
(node:48448) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

My package.json

{
  "name": "nsfw-node-test",
  "description": "test",
  "version": "1.1.3",
  "author": {
    "name": "Loreto Parisi",
    "email": "loretoparisi@gmail.com"
  },
  "main": "lib/index",
  "engines": {
    "node": "*"
  },
  "scripts": {},
  "devDependencies": {},
  "keywords": [],
  "dependencies": {
    "@tensorflow/tfjs-node": "latest",
    "node-fetch": "^2.2.0"
  }
}

Issue Analytics

State:
Created 5 years ago
Comments:9

Top GitHub Comments

6reactions

nsthoratcommented, Mar 19, 2019

+1 we will prioritize it, it should be pretty simple!

2reactions

nsthoratcommented, Mar 19, 2019

I think the issue is you need to pass a canvas object to tf.browser.fromPixels, but you are passing an Image object. If you look at the node-canvas documentation you can draw the image to the canvas with:

const canvas = createCanvas(width, height);
const ctx = canvas.getContext('2d');
...
ctx.drawImage(image, 0, 0, width, height);
tf.browser.fromPixels(canvas).print();