Use AWS Rekognition & Wia to Detect Faces, Labels & Text

Detect Faces

Get Number of Faces

Create a Flow with the following nodes:

• Event

• Detect Faces (by AWS)

• Run Function

• Send Email

It should look like the one below.

In the Event node, set the Event Name to photo and add the Devices you would like the Flow to be triggered by.

In the Run Function node, add the following code to get the number of faces in the image.

• Run Function Node

if (input.body.faceDetails) {  var faceCount = input.body.faceDetails.length;  output.body.faceCount = faceCount;} else {   output.body.faceCount = 0;}

In the Send Email node, set the To Address and Subject line. In the Body of the email, add the following text.

• Send Email Node

Found ${input.body.faceCount} faces.

Publish an Event to Wia with the following parameters:

• name - photo

• file - Buffer of your file

After a few seconds you should be able to see the Event in your dashboard and receive an email to your To Address in the Send Email node.

Get Details of a Face

To access the details of a face, edit the code in the Run Function node.

You can get a particular face using the code input.body.faceDetails[i] where i is the face instance you would like to get.

The following variables are available:

Example: How to check if someone is smiling

Build a Flow the same way as in the Get Number of Faces example above. In the Run Function node, change the code to the following:

• Run Function Node

if (input.body.faceDetails) {  if (input.body.faceDetails.length > 0) {    var face = input.body.faceDetails[0];    output.body.isSmiling = face.smile.value;  }} else {  output.body.isSmiling = false;}

In the Send Email node, set the To Address and Subject line. In the Body of the email, add the following text.

• Send Email Node

Person smiling: ${input.body.isSmiling}

Detect Labels

This detects instances of real-world entities within an image. This includes objects like flower, tree, and table; events like wedding, graduation, and birthday party; and concepts like landscape, evening, and nature.

Get a List of Labels

Create a Flow with the following nodes:

• Event

• Detect Labels (by AWS)

• Run Function

• Send Email

It should look like the one below.

In the Event node, set the Event Name to photo and add the Devices you would like the Flow to be triggered by.

In the Run Function node the following variables are available in the input variable.

Field NameType

labels

Array

labels[i].confidence Replace i by instance number you would like to return e.g. 0, 1, etc.

Number

labels[i].nameReplace i by instance numberyou would like to return e.g. 0, 1, etc.

String

orientationCorrection

String

Add the following code to get the labels of the photo:

• Run Function Node

output.body = JSON.stringify(input.body, null, 2);

In the Send Email node, set the To Address to your email address and Subject line to 'Detect Labels'. In the Body of the email, add the following text.

• Send Email Node

Got labels: ${input.body}

Publish an Event to Wia with the following parameters:

• name - photo

• file - Buffer of your file

After a few seconds you should be able to see the Event in your dashboard and receive an email to your To Address in the Send Email node.

Detect Text

Detects text in the input image and converts it into machine-readable text.

Get a List of Texts

Create a Flow with the following nodes:

• Event

• Detect Text (by AWS)

• Run Function

• Send Email

It should look like the one below.

In the Event node, set the Event Name to photo and add the Devices you would like the Flow to be triggered by.

In the Run Function node the following variables are available in the input variable.

Add the following code to get the texts of the photo:

• Run Function Node

var textList = [];input.body.textDetections.forEach(function(td) {	textList.push({  	confidence: td.confidence,    detectedText: td.detectedText  });});output.body = JSON.stringify(textList, null, 2);

In the Send Email node, set the To Address to your email address and Subject line to 'Detect Text'. In the Body of the email, add the following text.

• Send Email Node

Got texts: ${input.body}

Publish an Event to Wia with the following parameters:

• name - photo

• file - Buffer of your file

After a few seconds you should be able to see the Event in your dashboard and receive an email to your To Address in the Send Email node.

*Amazon Rekognition makes it easy to add image to your applications. You just provide an image to the Rekognition API, and the service can identify the objects, people, text, scenes, and activities, as well as detect any inappropriate content. Amazon Rekognition also provides highly accurate facial analysis and facial recognition. You can detect, analyze, and compare faces for a wide variety of user verification, cataloging, people counting, and public safety use cases.