Here is the script I used for Emotion Recognition in Unity [Microsoft Cognitive Services]

EmotionService.cs

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Globalization;
using System;

public class EmotionService : MonoBehaviour {

    WebCamTexture webCamTexture;
    public float photoInterval = 1.0f;
    public float time;
    public int num = 0;
    public string aiUrl = "https://westus.api.cognitive.microsoft.com/emotion/v1.0/recognize";
    public string secretKey = "YOUR-SECRET-KEY";
    private byte[] lastPhoto;
    public bool isActive = true;

    public Texture2D[] textures;


    void Awake()
    {
        time = photoInterval;
        isActive = SceneInteractions.isEmotionServiceActive;
    }
    void Start()
    {

        if (isActive)
        {
            if (WebCamTexture.devices.Length > 1)
			    webCamTexture = new WebCamTexture(WebCamTexture.devices[1].name);
            else
                webCamTexture = new WebCamTexture();
            webCamTexture.Play();
			
        }
        
        //TakePhoto();
    }
    void Update()
    {
        transform.position = new Vector3(transform.position.x, GameObject.Find("Main Camera").GetComponent<Camera>().ViewportToWorldPoint(new Vector3(0.8f, 0.92f, 0)).y, transform.position.z);

        if (isActive)
        {
            time -= Time.deltaTime;
            if (time < 0)
            {
                StartCoroutine(TakePhoto());
                time = photoInterval;

            }
        }
            
    }

    IEnumerator TakePhoto()
    {

        // NOTE - you almost certainly have to do this here:

        yield return new WaitForEndOfFrame();

        

        Texture2D photo = new Texture2D(webCamTexture.width, webCamTexture.height);
        photo.SetPixels(webCamTexture.GetPixels());
        photo.Apply();
        if (WebCamTexture.devices.Length > 1)
            photo = rotateTexture(photo);
        //GameObject.Find("front").GetComponent<Renderer>().material.mainTexture = photo;
        //Encode to a JPG for upload speed
        lastPhoto = photo.EncodeToJPG(30);
        //File.WriteAllBytes("photo" + num +".jpg", lastPhoto);
        sendPhoto();
        Debug.Log("took photo");
        
        num++;
    }

    void sendPhoto()
    {

        Dictionary<string, string> headers = new Dictionary<string, string>();
        headers["Content-Type"] = "application/octet-stream";
        headers["Ocp-Apim-Subscription-Key"] = secretKey;
        WWW www = new WWW(aiUrl, lastPhoto, headers);
        StartCoroutine(WaitForRequest(www));
    }
    IEnumerator WaitForRequest(WWW www)
    {
        Debug.Log("started to send");
        yield return www;
        Debug.Log("came back");
        // check for errors
        if (www.error == null)
        {
            if (www.text.Length > 100)
            {
                string happiness = www.text.Substring(www.text.IndexOf("happiness") + 11, www.text.IndexOf("neutral") - (www.text.IndexOf("happiness") + 13));

                float happinessIndex = float.Parse(happiness, CultureInfo.InvariantCulture.NumberFormat);
                broadcastEmotion(happinessIndex);
            }else
            {
                Debug.Log(www.text);
            }
            
        }
        else
        {
            Debug.Log("WWW Error: " + www.error);
        }
    }

    void broadcastEmotion(float happinessIndex)
    {
        //score
        string stringOnScene = string.Format("{0:0}", happinessIndex * 10);
        int integerFormat = Convert.ToInt32(stringOnScene);
        SceneInteractions.score += integerFormat;
        Debug.Log("brd: " + happinessIndex + "form" + integerFormat);

        //smiley update
        if (integerFormat <= 2)
            GetComponent<Renderer>().material.mainTexture = textures[0];
        else if (integerFormat <= 4)
            GetComponent<Renderer>().material.mainTexture = textures[1];
        else if (integerFormat <= 6)
            GetComponent<Renderer>().material.mainTexture = textures[2];
        else if (integerFormat <= 8)
            GetComponent<Renderer>().material.mainTexture = textures[3];
        else if (integerFormat <= 10)
            GetComponent<Renderer>().material.mainTexture = textures[4];
        
        //speed
        GameObject.Find("Player").GetComponent<PlayerRun>().takeHappinessIndex(happinessIndex);

    }


    public Texture2D rotateTexture(Texture2D image)
    {

        Texture2D target = new Texture2D(image.height, image.width, image.format, false);    //flip image width<>height, as we rotated the image, it might be a rect. not a square image

        Color32[] pixels = image.GetPixels32(0);
        pixels = rotateTextureGrid(pixels, image.width, image.height);
        target.SetPixels32(pixels);
        target.Apply();

        //flip image width<>height, as we rotated the image, it might be a rect. not a square image

        return target;
    }

    public Color32[] rotateTextureGrid(Color32[] tex, int wid, int hi)
    {
        Color32[] ret = new Color32[wid * hi];      //reminder we are flipping these in the target

        for (int y = 0; y < hi; y++)
        {
            for (int x = 0; x < wid; x++)
            {
                ret[(hi - 1) - y + x * hi] = tex[x + y * wid];         //juggle the pixels around

            }
        }

        return ret;
    }
}

@SouhaF I don't know. This is from 2016, likely everything has changed.