Implementing OCR Using Azure Cognitive Services with HTML5 Media Capture API

process-text.cs

[Route("api")]
public class ApiController : Controller
{
  ...

  [Route("ocr")]
  [HttpPost]
  public async Task<IActionResult> ProcessText(IFormFile file)
  {
    // Retrives the file data from Request.Form instance,
    // in case the file instance is null
    if (file == null)
    {
      file = this.Request.Form.Files.FirstOrDefault();
    }

    OcrResults result;
    string imagePath;
    using (var stream = file.OpenReadStream())
    {
      // Puts the API key here
      var client = new VisionServiceClient("[VISION_API_KEY_HERE]");
      try
      {
        // Gets the OCR result from Cognitive Services Vision API
        result = await client.RecognizeTextAsync(stream, languageCode: "en", detectOrientation: true);

        // Gets the image data back
        using (var ms = new MemoryStream())
        {
          await file.CopyToAsync(ms).ConfigureAwait(false);
          var base64 = Convert.ToBase64String(ms.ToArray());
          var value = $"data:{file.ContentType};base64,{base64}";
          imagePath = value;
        }
      }
      catch (Exception e)
      {
        Console.WriteLine(e);
        throw;
      }
    }

    var settings = new JsonSerializerSettings() { Formatting = Formatting.Indented };
    return Json(new { Result = result, ImagePath = imagePath }, settings);
  }

  ...
}