With the ever growing use of social media platforms like FaceBook, Twitter, Linked In to promote business, analyzing what the users feel and what feedback they share regarding the business is going to be of paramount importance. One such scenario is where the users post there feedback in images on the concerned company's social media pages. It is of great importance that the companies analyze what the users post on their social media pages as it will give them an overall idea of the sentiment of the users towards the services offered by the company, which in turn will help them plan their marketing strategies accordingly.
As per MicroSoft,
Microsoft Cognitive Services( formerly Project Oxford) are a set of APIs, SDKs and services available to the developers to make their applications more intelligent, engaging and discover able. Microsoft Cognitive Services expands on Microsoft's evolving portfolio of machine learning APIs and enables developers to easily add intelligent features such as emotion and video detection; facial, speech and vision recognition; and speech and language understanding - into their applications. Our vision is for more personal computing experiences and enhanced productivity aided by systems that increasingly can see hear, speak, understand and even begin to reason.
This article explains the concept of the Sentiment analysis of the text detected from an Image using a Sample Console Application. The article assumes that the user is familiar with the basic concepts of C# and know how to consume the REST Apis in the C# code. In This Sample Application, images from a SampleImage folder are read and then the image is sent to the Computer Vision Api to detect the text from the image. Once the Computer Vision api returns the json payload, the detected text is sent to the Text Analytics Api to detect the sentiment score.
In order to use the Computer Vision Api in the Sample Application, first an Api account for the Computer Vision Api needs to be created. Once this is done, the Api will be available to integrate the Computer Vision Api in the Sample Application. Following screenshot shows the process to do so.
Once the API account is created, select the account from the dashboard and following window is visible, the access keys and end point are required from this window which will be used to create a connection to the Computer Vision Api.
Text Analytics Api Account
In order to use the Text Analytics Api in the Sample Application, first an Api account for the Text Analytics Api needs to be created. Once this is done, the Api will be available to integrate the Text Analytics in the Sample Application. Following screenshot shows the process to do so.
Once the API account is created, select the account from the dashboard and following window is visible, the access keys and end point are required from this window which will be used to create a connection to the Text Analytics API.
The constants class is used to store the constant values that are used across the application. Following is the constants class used in the application.
01.using
System;02.using
System.Collections.Generic;03.using
System.Linq;04.using
System.Text;05.using
System.Threading.Tasks;06. 07.namespace
ImageTextSentimentDetection08.{09. public
class
Constants10. {11. /// <summary>12. /// Key
Name that is used to pass the subscrption Key Value in the Request Headers13. /// </summary>14. /// <summary>12. /// Key
Name that is used to pass the subscrption Key Value in the Request Headers13. public
static
string SubscriptionKeyName = "Ocp-Apim-Subscription-Key";15. 16. /// <summary>17. /// Uri
for the Computer Vision APi to which the Request Will be routed18. /// </summary>19. public
static
string VisionApiUri = "https://southeastasia.api.cognitive.microsoft.com/vision/v1.0";20. 21. /// <summary>22. /// Uri
for the Text Analytics Api to which the Request will be routed.23. /// </summary>24. public
static
string TextAnalyticsApiUri = "https://southeastasia.api.cognitive.microsoft.com/text/analytics/v2.0";25. 26. /// <summary>27. /// Path
to the SampleImages Folder28. /// </summary>29. public
static
string SampleImagesFolderPath = @"..\..\SampleImages";30. 28.31. /// <summary>32. /// Vision
APi Subscription Key Value. This needs to be populated before Starting the Sample33. /// </summary>34. public
static
string VisionApiSubcriptionKey = "Enter key here";35. 36. /// <summary>37. /// Text
Analytics Subscription Key value. This Needs to be Populated before Starting the Sample38. /// </summary>39. // public
static string TextAnalyticsApiSubscriptionKey = "Enter key here";40. 41. 42. }43.}This class is used to convert the json payload received from the Computer Vision Api into a C# class which can be used later on for extracting text. The class is generated using the sample json payload received from the Computer Vision Api. The class structure will change if the response received is change,
01.// To parse this JSON data, add NuGet
'Newtonsoft.Json' then do:02.//03.// using ImageTextSentimentDetection;04.//05.// var data = ComputerVisionSuccessFullResponseClass.FromJson(jsonString);06. 07.namespace
ImageTextSentimentDetection08.{09. using
System;10. using
System.Net;11. using
System.Collections.Generic;12. 13. using
Newtonsoft.Json;14. 15. public
partial
class ComputerVisionSuccessFullResponseClass16. {17. [JsonProperty("language")]18. public
string
Language { get;
set; }19. 20. [JsonProperty("textAngle")]string
Language { get;
set; }19. 21. public
double
TextAngle { get;
set; }22. 23. [JsonProperty("orientation")]24. public
string
Orientation { get;
set; }25. 26. [JsonProperty("regions")]27. public
Region[] Regions { get;
set; }28. }29. 30. public
partial
class Region31. {32. [JsonProperty("boundingBox")]33. public
string
BoundingBox { get;
set; }34. 35. [JsonProperty("lines")]36. public
Line[] Lines { get;
set; }37. }38. 39. public
partial
class Line40. {41. [JsonProperty("boundingBox")]42. public
string
BoundingBox { get;
set; }43. 44. [JsonProperty("words")]45. public
Word[] Words { get;
set; }46. }47. 48. public
partial
class Word49. {50. [JsonProperty("boundingBox")]51. public
string
BoundingBox { get;
set; }52. 53. [JsonProperty("text")]54. public
string
Text { get;
set; }55. }56. 57. public
partial
class ComputerVisionSuccessFullResponseClass58. {59. public
static
ComputerVisionSuccessFullResponseClass FromJson(string
json)60. {61. return
JsonConvert.DeserializeObject<ComputerVisionSuccessFullResponseClass>(json, Converter.Settings);62. }63. }64. 65. public
static
class Serialize66. 63. }64. /code>{67. public
static
string ToJson(this
ComputerVisionSuccessFullResponseClass self)68. {69. return
JsonConvert.SerializeObject(self, Converter.Settings);70. }71. }72. 73. public
class
Converter74. {75. public
static
readonly JsonSerializerSettings Settings =
new
JsonSerializerSettings76. {77. MetadataPropertyHandling
= MetadataPropertyHandling.Ignore,78. DateParseHandling
= DateParseHandling.None,79. };80. }81.}This class is used to convert the json payload received from the Text Analytics Api into a C# class which can be used later on for extracting text. The class is generated using the sample json payload received from the Text Analytics Api. The class structure will change if the response received is change,
}01.// To parse this JSON data, add NuGet
'Newtonsoft.Json' then do:02.//03.// using ImageTextSentimentDetection;04.//05.// var data = TextAnalyticsResponseClass.FromJson(jsonString);06. 07.namespace
ImageTextSentimentDetection08.{09. using
System;10. using
System.Net;11. using
System.Collections.Generic;12. 13. using
Newtonsoft.Json;14. 15. public
partial
class TextAnalyticsResponseClass16. {17. [JsonProperty("documents")]18. public
Document[] Documents { get;
set; }19. 20. [JsonProperty("errors")]21. public
Error[] Errors { get;
set; }22. }23. 24. public
partial
class Document25. {26. [JsonProperty("score")]27. public
long
Score { get;
set; }28. 29. [JsonProperty("id")]30. public
string
Id { get;
set; }31. }32. 33. public
partial
class Error31. }32. {35. [JsonProperty("id")]36. public
string
Id { get;
set; }37. 38. [JsonProperty("message")]39. public
string
Message { get;
set; }40. }41. 42. public
partial
class TextAnalyticsResponseClass43. {44. public
static
TextAnalyticsResponseClass FromJson(string
json)45. {46. return
JsonConvert.DeserializeObject<TextAnalyticsResponseClass>(json, Converter.Settings);47. }48. }49. 50.}47. }
Helper classes are created to cater to each of the Cognitive Api calls. One class caters to the Computer Vision Api call while other class caters to the Text Analytics Api call. Each of them is discussed below.
This class caters to the calls made to the Computer Vision Api. In this current Sample the DetectTextInImage method in the class is used to call the Computer Vision Api. This method passes the image to the api in 'application/octet-stream' format. It deserializes the json payload into the class created earlier and extracts out the detected text. The class is as follows.
01.using
System;02.using
System.Collections.Generic;03.using
System.Linq;04.using
System.Text;05.using
System.Threading.Tasks;06.using
Newtonsoft.Json.Serialization;07.using
System.Net.Http;08.using
System.Net.Http.Headers;09.using
System.Web;10. 11.namespace
ImageTextSentimentDetection12.{13. public
class
VisionHelper14. {15. public
static
string DetectTextInImage(byte[] imageBytes)16. {17. string
detectedText = String.Empty;18. 19. var
queryString = HttpUtility.ParseQueryString(String.Empty);20. 21. HttpClient
client = new
HttpClient();22. 23. using
(var content = new
ByteArrayContent(imageBytes))24. {25. client.DefaultRequestHeaders.Add(Constants.SubscriptionKeyName,
Constants.VisionApiSubcriptionKey);26. 27. queryString["language"]
= "unk";28. queryString["detectOrientation
"] = "false";29. content.Headers.ContentType
= new
MediaTypeHeaderValue("application/octet-stream");30. var
uriString = Constants.VisionApiUri + "/ocr?"
+ queryString;31. HttpResponseMessage
response = new
HttpResponseMessage();32. response
= client.PostAsync(uriString, content).Result;33. 34. var
responseJson = response.Content.ReadAsStringAsync().Result;35. 36. if
(response.StatusCode == System.Net.HttpStatusCode.OK)37. {38. var
data = ComputerVisionSuccessFullResponseClass.FromJson(responseJson);39. 40. foreach
(Region region in
data.Regions)41. {42. foreach
(Line line in
region.Lines)43. {44. foreach
(Word word in
line.Words)45. {46. detectedText
= detectedText + " "
+ word.Text;47. }48. }49. }50. }51. else52. {53. detectedText
= "Error Occured While Calling Computer Vision Api";54. }55. return
detectedText;56. }57. 58. }59. }60.}This class caters to the Text Analytics Api call from the Sample Application. In current context, the DetectSentiment method in the class accepts the detected string as input. It then creates the json payload and then invokes the Text Analytics Api. It Deserializes the json payload received from the api call into the response class and extracts out the sentiment score. This method is designed to pass only one detected text at a time to the Text Analytics Api, but it can be modified as required. The class is as follows.
01.using
System;02.using
System.Collections.Generic;03.using
System.Linq;04.using
System.Text;05.using
System.Threading.Tasks;06.using
Newtonsoft.Json;07.using
System.Net.Http;08.using
System.Net.Http.Headers;09.using
System.Web;10. 11.namespace
ImageTextSentimentDetection12.{13. public
class
SentimentHelper14. {15. public
static
string 13. public
class
SentimentHelper14. {15. public
static DetectSentiment(string
detectedText)16. {17. string
sentimentScore = String.Empty;18. string
jsonText = "{\"documents\":[{\"language\":\"en\",\"id\":\"1\",\"text\":\""
+ detectedText + "\"}]}";19. 20. HttpClient
client = new
HttpClient();21. byte[]
detectedTextBytes = Encoding.UTF8.GetBytes(jsonText);22. using
(var content = new
ByteArrayContent(detectedTextBytes))23. {24. var
queryString = HttpUtility.ParseQueryString(String.Empty);25. client.DefaultRequestHeaders.Add(Constants.SubscriptionKeyName,
Constants.TextAnalyticsApiSubscriptionKey);26. var
uriString = Constants.TextAnalyticsApiUri + "/sentiment?"
+ queryString;27. content.Headers.ContentType
= new
MediaTypeHeaderValue("application/json");28. &="color:#000000;">var
uriString = Constants.TextAnalyticsApiUri + "/sentiment?"
+ queryString;27. HttpResponseMessage
response = new
HttpResponseMessage();29. response
= client.PostAsync(uriString, content).Result;30. 31. if
(response.StatusCode == System.Net.HttpStatusCode.OK)32. {33. var
data = TextAnalyticsResponseClass.FromJson(response.Content.ReadAsStringAsync().Result);34. foreach
(var document in
data.Documents)35. {36. sentimentScore
= Convert.ToString(document.Score);37. }38. }39. else40. {41. sentimentScore
= "Error";42. }43. 44. }45. 46. 47. return
sentimentScore;48. }49. 50. }51.}The console application, greets the user and advises user to ensure that the Subscription keys for the Computewr Vision Api and Text Analytics Api are generated and added to the Constants class. It then asks the user to confirm to proceed by Accepting [Y/N] input. Once done, it reads the files stored in the SampleImages projects and calls the helpers on each of the images. Following is the Console Application class.
01.using
System;02.using
System.Collections.Generic;03.using
System.Linq;04.using
System.Text;05.using
System.Threading.Tasks;06.using
System.IO;07.using
System.Reflection;08.using
System.Globalization;09.namespace
ImageTextSentimentDetection10.{11. public
class
ImageTextSentimentDetctionApp12. {13. static
void
Main(string[] args)14. {15. string
visionApiSubcriptionKey = String.Empty;16. string
textAnalyticsApiSubscriptionKey = String.Empty;17. 18. Console.WriteLine("Welcome
to the Image Text Detection Sample Application");19. Console.WriteLine("This
Application will Get the Images From the SampleImages Folder");20. Console.WriteLine("Once
the Image is read, the Sample APplication Will call Computer Vision Api and Try to Detect Text in the Image"); ;21. Console.WriteLine("ON
SuccessFull Detection of text, the Application will use Text Analystics To Detect The Sentiment of APi");22. Console.WriteLine("To
Run this Sample Application, You need to generate the Subscription Key for the Computer Vision and Text Analytics Api.");23. Console.WriteLine("ON
SuccessFull Detection of text, the Application will use Text Analystics To Detect The Sentiment of APi");22. Console.WriteLine(Console.WriteLine("Do
You Wish To Continue? Press Y for yes and N for No");24. try25. {26. if
(Convert.ToString(Console.ReadKey().Key).ToUpper() ==
"Y")27. {28. Console.WriteLine(Environment.NewLine);29. Console.WriteLine("Starting
The Application Flow");30. 31. foreach
(string
imageFile in
Directory.GetFiles(Constants.SampleImagesFolderPath,
"*.jpg"))32. {33. var
imageFileInfo = new
FileInfo(imageFile);34. 35. byte[]
imageBytes = File.ReadAllBytes(imageFileInfo.FullName);36. 37. Console.WriteLine("File
Name of the FileRead :" + imageFileInfo.Name);38. Console.WriteLine("Initiating
the Image TextDetection");39. string
detectedText = VisionHelper.DetectTextInImage(imageBytes);40. if
(detectedText.Contains("Error"))41. break;42. Console.WriteLine("Text
Detected in Image:" + detectedText);43. Console.WriteLine("Starting
Sentiment Score analysis for the detected text");44. string
sentimentScore = SentimentHelper.DetectSentiment(detectedText);45. if
(sentimentScore.Contains("Error"))46. break;47. Console.WriteLine("Sentiment
Score for the Detected Text is :" + sentimentScore);48. }49. }50. else51. {52. Console.WriteLine("Thank
You For Visiting the Application Will Exit Now.");53. }54. }55. catch
(Exception ex)56. {57. Console.WriteLine("Sorry
an Exception Was Caught!!");58. Console.WriteLine("Following
are the Exception Details");59. Console.WriteLine(ex.Message);60. }61. Console.WriteLine("Press
Any Key To Exit");62. Console.ReadKey();63. 64. }65. }66.}Following are the images that were used to test the Sample application.
The Result obtained from the Test Console Application is as follows
Actual result for the text analysis for the text detected from above test messages when done on the Microsoft Demo Page ( For Details See References) are shown below.
Visual result for the sentiment analysis of the text in the first test image is as shown below.
Visual result for the sentiment analysis of the text in the second test image is as shown below.
The test results as observed from the Sample Console Application as well as from the Microsoft Demo Tool are exactly the same proving the successful consumption of the Computer Vision Api and Text Analytics Api.
The source code can be found at the TechNet Gallery at Source Code For Image Text Sentiment Analysis using Vision and Text Analytics Api
Following material was referred to while writing this article.