MagicMirror² v2.13.0 is available! For more information about this release, check out this topic.

MMM-Face-Reco-DNN receiving PythonShellError: TypeError

  • I am trying to get facial recognition working but it is not happening. Here is what I have found. Any advice on how to get this to work?

    I have loaded the MMM-Face-Reco-DNN and even used the from with the encodings file generated from the MMM-Face-Reco-DNN instructions and had that .py file recognize faces. So I backed everything out of my config file except the default MMM-Face-Reco-DNN settings from the instructions and when I manually start MM2 everything looks fine. I am running on a Raspberry Pi 4. I did install a different facial recognition module, but it was not in the config file and decided not to use it when I saw it only recognized 1 person. When I step in front of the camera, this comes up in the terminal where I manually started MM2:

    [2020-08-09 00:59:28.399] [ERROR]  Whoops! There was an uncaught exception...
    [2020-08-09 00:59:28.400] [ERROR]  PythonShellError: TypeError: ' (/home/pi/MagicMirror/modules/MMM-Face-Reco-DNN/node_modules/python-shell/index.js:121:13)
        at ChildProcess.emit (events.js:200:13)
        at Process.ChildProcess._handle.onexit (internal/child_process.js:272:12)
        ----- Python Traceback -----
        File "modules/MMM-Face-Reco-DNN/tools/", line 143, in 
          if minDistance < args["tolerance"]: {
      traceback: 'Traceback (most recent call last):\n  File ' +
        '"modules/MMM-Face-Reco-DNN/tools/", line ' +
        '143, in \n    if minDistance < args["tolerance"]:\n' +
        "TypeError: '< ' not supported between instances of " +
        "'numpy.ndarray' and 'str'\n",
      executable: 'python3',
      options: null,
      script: 'modules/MMM-Face-Reco-DNN/tools/',
      args: [
      exitCode: 1
    [2020-08-09 00:59:28.409] [ERROR]  MagicMirror will not quit, but it might be a good idea to check why this happened. Maybe no internet connection?
    [2020-08-09 00:59:28.409] [ERROR]  If you think this really is an issue, please open an issue on GitHub:

    Here is my config.js

    /* Magic Mirror Config Sample
     * By Michael Teeuw
     * MIT Licensed.
     * For more information on how you can configure this file
     * See
    var config = {
    	address: "",
    	port: 8080,
    	basePath: "/", 	// The URL path where MagicMirror is hosted. If you are using a Reverse proxy
    					// you must set the sub path here. basePath must end with a /
    	ipWhitelist: [],
    	useHttps: false, 		// Support HTTPS or not, default "false" will use HTTP
    	httpsPrivateKey: "", 	// HTTPS private key path, only require when useHttps is true
    	httpsCertificate: "", 	// HTTPS Certificate path, only require when useHttps is true
    	language: "en",
    	logLevel: ["INFO", "LOG", "WARN", "ERROR"],
    	timeFormat: 12,
    	units: "imperial",
    	// serverOnly:  true/false/"local" ,
    	// local for armv6l processors, default
    	//   starts serveronly and then starts chrome browser
    	// false, default for all NON-armv6l devices
    	// true, force serveronly mode, because you want to.. no UI on this device
    	modules: [
    			module: "alert",
    			classes: 'default everyone',
    			module: "updatenotification",
    			classes: 'default everyone',
    			position: "top_bar"
    			module: "clock",
    			classes: 'default everyone',
    			position: "top_left"
    			module: 'MMM-Face-Reco-DNN',
    			config: {
    			  // Logout 15 seconds after user was not detected any more
    			  // If they are detected within this period, the delay will start again
    			  logoutDelay: 15000,
    			  // How often the recognition starts in milliseconds
    			  // With a Raspberry Pi 3+ it works well every 2 seconds
    			  checkInterval: 2000,
    			  // Module set used for strangers or if no user is detected
    			  defaultClass: 'default',
    			  // Set of modules which should be shown for every recognised user
    			  everyoneClass: 'everyone',
    			  // XML to recognize with haarcascade
    			  cascade: 'modules/MMM-Face-Reco-DNN/tools/haarcascade_frontalface_default.xml',
    			  // Pre-encoded pickle with the faces
    			  encodings: 'modules/MMM-Face-Reco-DNN/tools/encodings.pickle',
    			  // Use Raspberry Pi camera or another type
    			  // 1 = RasPi camera, 0 = other camera
    			  usePiCamera: 1,
    			  // If using another type of camera, you can choose
    			  // i.e. 0 = /dev/video0 or ''
    			  source: 0,
    			  // Rotate camera
    			  rotateCamera: 0,
    			  // Method of facial recognition
    			  // dnn = deep neural network, haar = haarcascade
    			  method: 'dnn',
    			  // Which face detection model to use
    			  // "hog" is less accurate but faster on CPUs
    			  // "cnn" is a more accurate deep-learning model which is GPU/CUDA accelerated
    			  detectionMethod: 'hog',
    			  // How long in milliseconds modules take to hide and show
    			  animationSpeed: 0,
    			  // Path to Python to run the face recognition
    			  // null or '' means default path
    			  pythonPath: null,
    			  // Should a welcome message be shown using the MagicMirror alerts module?
    			  welcomeMessage: true,
    			  // Capture new pictures of recognized people, if unknown we save it in folder "unknown"
    			  // So you can extend your dataset and retrain it afterwards for better recognitions
    			  extendDataset: false,
    			  // If extendDataset is true, you need to set the full path of the dataset
    			  dataset: 'modules/MMM-Face-Reco-DNN/dataset/',
    			  // How much distance between faces to consider it a match. Lower is more strict.
    			  tolerance: 0.6
    /*************** DO NOT EDIT THE LINE BELOW ***************/
    if (typeof module !== "undefined") {module.exports = config;}

    And here is everything in the terminal before stepping in front of the camera:

    pi@raspberrypi:~/MagicMirror $ npm start
    > magicmirror@2.12.0 start /home/pi/MagicMirror
    > DISPLAY="${DISPLAY:=:0}" ./node_modules/.bin/electron js/electron.js
    [2020-08-09 00:58:21.215] [LOG]    Starting MagicMirror: v2.12.0
    [2020-08-09 00:58:21.240] [LOG]    Loading config ...
    [2020-08-09 00:58:21.248] [LOG]    Loading module helpers ...
    [2020-08-09 00:58:21.251] [LOG]    No helper found for module: alert.
    [2020-08-09 00:58:21.325] [LOG]    Initializing new module helper ...
    [2020-08-09 00:58:21.326] [LOG]    Module helper loaded: updatenotification
    [2020-08-09 00:58:21.328] [LOG]    No helper found for module: clock.
    [2020-08-09 00:58:21.354] [LOG]    Initializing new module helper ...
    [2020-08-09 00:58:21.355] [LOG]    Module helper loaded: MMM-Face-Reco-DNN
    [2020-08-09 00:58:21.355] [LOG]    All module helpers loaded.
    [2020-08-09 00:58:21.566] [LOG]    Starting server on port 8080 ... 
    [2020-08-09 00:58:21.574] [INFO]   You're using a full whitelist configuration to allow for all IPs
    [2020-08-09 00:58:21.580] [LOG]    Server started ...
    [2020-08-09 00:58:21.581] [LOG]    Connecting socket for: updatenotification
    [2020-08-09 00:58:21.583] [LOG]    Connecting socket for: MMM-Face-Reco-DNN
    [2020-08-09 00:58:21.583] [LOG]    Starting module helper: MMM-Face-Reco-DNN
    [2020-08-09 00:58:21.584] [LOG]    Sockets connected & modules started ...
    [2020-08-09 00:58:21.891] [LOG]    Launching application.
    [2020-08-09 00:58:25.058] [INFO]   Checking git for module: MMM-Face-Reco-DNN
    [2020-08-09 00:58:32.928] [LOG]    [MMM-Face-Reco-DNN] loading encodings + face detector...
    [2020-08-09 00:58:33.177] [LOG]    [MMM-Face-Reco-DNN] starting video stream...

  • @KSumwalt it seems that python has added type checking, which it wasn’t using before.

    there was another python related type checking problem a few days ago…

    looks like the node_helper has launched the python script to compare the face files, and run into a problem checking the parms passed to it.

  • @sdetweil Thank you. I have passed this on as an issue on the github site for the plugin.

  • @KSumwalt , hi! Check the module update.

  • Beautiful! I updated and it appears to be working fine. Thank you, @x3mEr !!!

Log in to reply