dlib-correlation-tracker-js

Track moving objects in videos in Javascript using dlib's correlation tracker. These bindings compile the module using emscripten, providing the raw interface as well as a utility class to simplify working with an HTML <video> element.

Usage

$ npm install --save dlib-correlation-tracker-js

To use the DOM interface, create a new VideoCorrelationTracker with an HTMLVideoElement and the position of the object to track. A new prediction can be generated based on the video's current frame at any time by referring to tracker.prediction. The tracker can be fine-tuned by updating it with a user-specified rect using tracker.update(rect).

import { VideoCorrelationTracker } from 'dlib-correlation-tracker';
 
// begin by passing a video and a bounding box of what you want to track
const tracker = new VideoCorrelationTracker(document.querySelector('video'), { x, y, width, height });
 
// update the tracker with a specified rect when the video updates
tracker.update({ x, y, width, height });
 
// get the tracker's prediction for the current video frame
const { x, y, width, height } = tracker.prediction;
 
// if the video dimensions change, memory must be manually re-allocated
function onVideoDimensionsChange(video) {
  VideoCorrelationTracker.reserveMemory(video);
}
 
// memory must also be manually freed when done!
function onUnload() {
  VideoCorrelationTracker.freeMemory();
}