Introduction
Microsoft Cognitive Services offer awesome APIs and services for developers to create more intelligent applications. You can add interesting features, like people's emotions and video detection, face, speech, and vision recognition and speech and language understanding into your application.
The Emotion API takes a facial expression in an image stream as an input, and returns confidence levels across a set of emotions for each face in the image, like anger, contempt, disgust, fear, happiness, neutral, sadness, and surprise, in a facial expression
Where we can implement it
There is no single unifying definition or theory of emotion. Nevertheless, several characteristics of an emotional reaction are frequently mentioned. Nowadays, feedback is more important for product promotion and review of the article and store, etc. Manual entry of emotion maybe wrong, so we automate the feedback and review.
In this article, we will learn how to implement Emotion Recognition in Xamarin.Forms with Microsoft Cognitive Services.
Getting Started with the Emotion API
The Emotion API can detect anger, contempt, disgust, fear, happiness, neutral, sadness, and surprise, as a facial expression, as well as, it returns an emotion result for a facial expression. The Emotion API also returns a bounding box for detected faces using the Face API. If a user has already called the Face API, he/she can submit the face rectangle as an optional input. Note that an API key must be obtained to use the Emotion API.
You can follow the below steps for obtaining a free API key on Microsoft.com
Step 1
Click here for generating Subscriber Key, and click on "Create".
Step 2
Agree to the terms and Microsoft privacy statement, select the country, and click on "Next".
Step 3
Login with Microsoft /LinkedIn /Facebook /GitHub for creating your application.
Step 4
You should see the keys and the below information available for your subscriptions.
We will use Emotion API key in the following Xamarin application. Before that, let's test the API key.
Test your Emotion Key
Navigate to the Emotion API online console application and provide the subscription key and image url. If your provided key is valid, you will get its JSon data as output or relevant error.
Create New Xamarin.Forms Application
You can refer to my previous article for setting up and creating new Xamarin.Forms application.
If you have already installed VS on your machine, open Visual Studio >> Create New Xamarin Forms application like below.
Solution will be created with all the platform and PCL projects.
In this solution, we are going to create demo application for Article review automate based on the emotion.
Camera in Xamarin. Forms
We can use Media.Plugin Nuget package for Capture image or select image gallery from all the mobile platform (iOS,Android,Windows)
Right Click on Solution > Type “xam.plugin” in the search box > Select all the project (PCL, iOS, Android and UWP) > Click on Install
Emotion Nuget Package
This client library is a thin C# client wrapper for the Microsoft Emotion API.The easiest way to use this client library is to get microsoft.projectoxford.emotion package from nuget .
Right Click on Solution > Type “Microsoft Emotion” in the search box > Select all the project (PCL, iOS, Android and UWP) > Click on Install
UI Design
After successfully install above two nuget package. Let start UI design from PCL project
In PCL Project > Open MainPage.Xaml page and design following xaml code
- <?xml version="1.0" encoding="utf-8" ?>
- <ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
- xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
- xmlns:local="clr-namespace:DevEnvExeEmotion"
- x:Class="DevEnvExeEmotion.MainPage">
- <StackLayout Margin="20">
- <StackLayout Orientation="Horizontal" Padding="30" HorizontalOptions="CenterAndExpand" >
- <StackLayout x:Name="emotion">
- <Label Text="Reader is :" FontSize="Large"/>
- <Label x:Name="emotionResultLabel" FontSize="Large" />
- </StackLayout>
- <Button Text="Share Your FeedBack" Clicked="OnFeedBackClicked"></Button>
- </StackLayout>
- <Image x:Name="image" Source="article.png" />
- <ActivityIndicator x:Name="activityIndicator" />
- </StackLayout>
-
- </ContentPage>
- In mainPage.xaml.cs file add your logic.
- public partial class MainPage : ContentPage
- {
- EmotionServiceClient emotionClient;
- MediaFile photo;
-
- public MainPage()
- {
- InitializeComponent();
- emotion.IsVisible = false;
- emotionClient = new EmotionServiceClient("7f495be5faf643adbeead444d5b79a13");
- }
- For capture image, write the following code
- public async Task CaptureImage()
- {
- await CrossMedia.Current.Initialize();
- emotion.IsVisible = false;
-
- if (CrossMedia.Current.IsCameraAvailable || CrossMedia.Current.IsTakePhotoSupported)
- {
- photo = await CrossMedia.Current.TakePhotoAsync(new StoreCameraMediaOptions
- {
- SaveToAlbum = false
-
- });
-
- }
- else
- {
- await DisplayAlert("No Camera", "Camera unavailable.", "OK");
- }
- }
- For Recognize emotion, write the following code
- public async Task Recognizeemotion()
- {
- try
- {
- if (photo != null)
- {
- using (var photoStream = photo.GetStream())
- {
-
- Emotion[] emotionResult = await emotionClient.RecognizeAsync(photoStream);
- if (emotionResult.Any())
- {
-
- emotionResultLabel.Text = emotionResult.FirstOrDefault().Scores.ToRankedList().FirstOrDefault().Key;
- emotion.IsVisible = true;
- }
- photo.Dispose();
- }
- }
- }
- catch (Exception ex)
- {
- Debug.WriteLine(ex.Message);
- }
- }
- While click on Feedback button, call the above two methods
- async void OnFeedBackClicked(object sender, EventArgs e)
- {
-
- await CaptureImage();
- ((Button)sender).IsEnabled = false;
-
- await Recognizeemotion();
- ((Button)sender).IsEnabled = true;
- }
Run the Application
Select the iOS /Android /Windows and install into the device and click on ‘Share your Feedback ‘button
The device should be camera so after click on the button, capture your face for Recognize emotion.
Summary
In this article, you learned how to generate Emotion API key and implement Emotion Recognition in Xamarin.Forms with Microsoft Cognitive Services.
If you have any questions/ feedback/ issues, please write in the comment box.