Azure Cognitive Service\Computer Visio\OCR - Can I use it into into WebSite C# - azure

Question

I'm trying to use Azure Ocr into my website c#.
I added the package Microsoft.Azure.CognitiveServices.Vision.ComputerVision and I wrote code, with key and endpoint of my subscription.
static string subscriptionKey = "mykey";
static string endpoint = "https://myocr.cognitiveservices.azure.com/";
private const string ANALYZE_URL_IMAGE = "https://raw.githubusercontent.com/Azure-Samples/cognitive-services-sample-data-files/master/ComputerVision/Images/printed_text.jpg";
protected void Page_Load(object sender, EventArgs e)
{
// Create a client
ComputerVisionClient client = Authenticate(endpoint, subscriptionKey);
// Analyze an image to get features and other properties.
AnalyzeImageUrl(client, ANALYZE_URL_IMAGE).Wait();
}
public static ComputerVisionClient Authenticate(string endpoint, string key)
{
ComputerVisionClient client =
new ComputerVisionClient(new ApiKeyServiceClientCredentials(key))
{ Endpoint = endpoint };
return client;
}
public static async Task AnalyzeImageUrl(ComputerVisionClient client, string imageUrl)
{
// Read text from URL
var textHeaders = await client.ReadAsync(imageUrl);
...
}
It seems all ok, but at line
var textHeaders = await client.ReadAsync(urlFile);
website crashes.
I don't understand why. No error, it's just stopped.
So I ask: azure ocr can to be use only with console app?
EDIT
The code is ok for ConsoleApp and WebApp but not working for my asp.net WEBSITE.
Could be a problem with async?

Answer 1

We can use OCR with web app also,I have taken the .net core 3.1 webapp in Visual Studio and installed the dependency of Microsoft.Azure.CognitiveServices.Vision.ComputerVision by selecting the check mark of include prerelease as shown in the below image:
After creating computer vision resource in Azure Portal, copied the key and endpoint from there and used inside the c# code.
using System;
using System.Collections.Generic;
using Microsoft.Azure.CognitiveServices.Vision.ComputerVision;
using Microsoft.Azure.CognitiveServices.Vision.ComputerVision.Models;
using System.Threading.Tasks;
using System.IO;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using System.Threading;
using System.Linq;
namespace ComputerVisionQuickstart
{
class Program
{
// Add your Computer Vision subscription key and endpoint
static string subscriptionKey = "c1****b********";
static string endpoint = ".abc.cognitiveservices.azure.com/";
private const string READ_TEXT_URL_IMAGE = "https://raw.githubusercontent.com/Azure-Samples/cognitive-services-sample-data-files/master/ComputerVision/Images/printed_text.jpg";
static void Main(string[] args)
{
Console.WriteLine("Azure Cognitive Services Computer Vision - .NET quickstart example");
Console.WriteLine();
ComputerVisionClient client = Authenticate(endpoint, subscriptionKey);
// Extract text (OCR) from a URL image using the Read API
ReadFileUrl(client, READ_TEXT_URL_IMAGE).Wait();
}
public static ComputerVisionClient Authenticate(string endpoint, string key)
{
ComputerVisionClient client =
new ComputerVisionClient(new ApiKeyServiceClientCredentials(key))
{ Endpoint = endpoint };
return client;
}
public static async Task ReadFileUrl(ComputerVisionClient client, string urlFile)
{
Console.WriteLine("----------------------------------------------------------");
Console.WriteLine("READ FILE FROM URL");
Console.WriteLine();
// Read text from URL
var textHeaders = await client.ReadAsync(urlFile);
// After the request, get the operation location (operation ID)
string operationLocation = textHeaders.OperationLocation;
Thread.Sleep(2000);
// Retrieve the URI where the extracted text will be stored from the Operation-Location header.
// We only need the ID and not the full URL
const int numberOfCharsInOperationId = 36;
string operationId = operationLocation.Substring(operationLocation.Length - numberOfCharsInOperationId);
// Extract the text
ReadOperationResult results;
Console.WriteLine($"Extracting text from URL file {Path.GetFileName(urlFile)}...");
Console.WriteLine();
do
{
results = await client.GetReadResultAsync(Guid.Parse(operationId));
}
while ((results.Status == OperationStatusCodes.Running ||
results.Status == OperationStatusCodes.NotStarted));
// Display the found text.
Console.WriteLine();
var textUrlFileResults = results.AnalyzeResult.ReadResults;
foreach (ReadResult page in textUrlFileResults)
{
foreach (Line line in page.Lines)
{
Console.WriteLine(line.Text);
}
}
Console.WriteLine();
}
}
}
The above code is taken from the Microsoft Document.
I can be able to read the text inside the image successfully as shown in the below screenshot: