The Industry-Leading C# HIN (Hull Identification Number) OCR Library

// Get 200 free credits:
// 👉 https://structocr.com/register

using System;
using System.IO;
using System.Net.Http;
using System.Text;
using System.Text.Json;
using System.Threading.Tasks;

public class HinOcrExample
{
    public static async Task Main(string[] args)
    {
        string apiKey = "YOUR_API_KEY"; 
        string imagePath = "path/to/boat_hin.jpg"; 

        try
        {
            // 1. Read the hull image file and convert it to Base64
            byte[] imageArray = await File.ReadAllBytesAsync(imagePath);
            string base64Image = Convert.ToBase64String(imageArray);

            // 2. Create the JSON payload
            var payload = new { img = base64Image };
            string jsonPayload = JsonSerializer.Serialize(payload);

            // 3. Configure the HTTP client
            using var httpClient = new HttpClient();
            httpClient.DefaultRequestHeaders.Add("x-api-key", apiKey);
            var content = new StringContent(jsonPayload, Encoding.UTF8, "application/json");

            // 4. Send the POST request to the StructOCR HIN endpoint
            HttpResponseMessage response = await httpClient.PostAsync("https://api.structocr.com/v1/hin", content);

            // 5. Handle the response
            if (response.IsSuccessStatusCode)
            {
                string responseBody = await response.Content.ReadAsStringAsync();
                using (JsonDocument document = JsonDocument.Parse(responseBody))
                {
                    JsonElement root = document.RootElement;
                    
                    // Read outer validation and confidence
                    Console.WriteLine($"HIN: {root.GetProperty("hin_number").GetString()}");
                    Console.WriteLine($"Is Valid: {root.GetProperty("is_valid").GetBoolean()}");
                    Console.WriteLine($"Confidence: {root.GetProperty("confidence").GetString()}");
                    
                    // Read deeply parsed data
                    JsonElement parsed = root.GetProperty("parsed");
                    Console.WriteLine($"Manufacturer: {parsed.GetProperty("manufacturer_code").GetString()}");
                    Console.WriteLine($"Year: {parsed.GetProperty("model_year").GetString()}");
                }
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine($"Exception: {ex.Message}");
        }
    }
}