C# Google Cloud Vision API - 구글 클라우드 비전 API 3

C# WinForm 으로 구글 클라우드 비전 API를 이용해 Detect localized objects in a single image 를 진행해 보자. 아래 링크를 참고해 기본 준비를 한다.

2022.02.11 - [C#] - C# Google Cloud Vision API - 구글 클라우드 비전 API 2

 

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
 
using Google.Cloud.Vision.V1;
 
namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        ImageAnnotatorClient client;
 
        public Form1()
        {
            InitializeComponent();
 
            try
            {
                client = new ImageAnnotatorClientBuilder
                {
                    CredentialsPath = "your_credentials.json"
                }.Build();
            }
            catch (Exception exc)
            {
                MessageBox.Show(exc.Message);
                Close();
            }
        }
 
        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                System.Drawing.Image systemImage;
 
                OpenFileDialog dlg = new OpenFileDialog();
                if (dlg.ShowDialog() == DialogResult.OK)
                {
                    systemImage = System.Drawing.Image.FromFile(dlg.FileName);
                    pictureBox1.Image = systemImage;
 
                    pictureBox1.Refresh();
 
                    Graphics graphics = pictureBox1.CreateGraphics();
 
                    Google.Cloud.Vision.V1.Image visionImage = Google.Cloud.Vision.V1.Image.FromFile(dlg.FileName);
 
                    IReadOnlyList<LocalizedObjectAnnotation> annotations = client.DetectLocalizedObjects(visionImage);
                    foreach (LocalizedObjectAnnotation annotation in annotations)
                    {
                        Google.Protobuf.Collections.RepeatedField<NormalizedVertex> normalizedVertices =
                            annotation.BoundingPoly.NormalizedVertices;
 
                        int imageWidth = systemImage.Width;
                        int imageHeight = systemImage.Height;
                        // Google.Cloud.Vision.V1.Image 는 Width, Height 필드가 없다.
 
                        Rectangle rectangle = new Rectangle(
                            (int)(normalizedVertices[0].X * imageWidth),
                            (int)(normalizedVertices[0].Y * imageHeight),
                            (int)((normalizedVertices[2].X - normalizedVertices[0].X) * imageWidth),
                            (int)((normalizedVertices[2].Y - normalizedVertices[0].Y) * imageHeight)
                            );
                        // BoundingPoly.NormalizedVertices 는 0~1의 범위를 가지는 값이다.
 
                        StringFormat stringFormat = new StringFormat
                        {
                            Alignment = StringAlignment.Center,
                            LineAlignment = StringAlignment.Center
                        };
 
                        graphics.DrawRectangle(System.Drawing.Pens.Red, rectangle);
                        graphics.DrawString($"Name: {annotation.Name}\n ID: {annotation.Mid}\n Score: {annotation.Score}",
                            Font, Brushes.Red, rectangle, stringFormat);
                    }
 
                    graphics.Dispose();
                }
            }
            catch (Exception exc)
            {
                MessageBox.Show(exc.Message);
            }
        }
    }
}

 

소스를 입력하고 빌드한다.