效果

 项目

VS2022+.net4.8+ OpenCvSharp4+Sdcb.RotationDetector

代码

using OpenCvSharp;
using Sdcb.RotationDetector;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace RotationDetector_图片旋转角度检测
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            startupPath = Application.StartupPath;
            rd = new PaddleRotationDetector(RotationDetectionModel.EmbeddedDefault);

        }

        Bitmap bmp;
        string fileFilter = "*.*|*.bmp;*.jpg;*.jpeg;*.tiff;*.tiff;*.png";
        string img = "";
        string startupPath = "";

        DateTime dt1 = DateTime.Now;
        DateTime dt2 = DateTime.Now;

        PaddleRotationDetector rd;

        private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog ofd = new OpenFileDialog();
            ofd.Filter = fileFilter;
            if (ofd.ShowDialog() != DialogResult.OK) return;

            pictureBox1.Image = null;

            img = ofd.FileName;
            bmp = new Bitmap(img);
            pictureBox1.Image = new Bitmap(img);
            textBox1.Text = "";

        }

        private void button2_Click(object sender, EventArgs e)
        {
            if (img=="") { return; }
            Mat src = OpenCvSharp.Extensions.BitmapConverter.ToMat(new Bitmap(pictureBox1.Image));
            Cv2.CvtColor(src, src, ColorConversionCodes.RGBA2RGB);//mat转三通道mat
            dt1 = DateTime.Now;
            RotationResult r = rd.Run(src);
            dt2 = DateTime.Now;
            StringBuilder sb = new StringBuilder();
            sb.AppendLine("图片旋转角度："+ r.Rotation );
            sb.AppendLine("--------------------");
            sb.AppendLine("耗时:" + (dt2 - dt1).TotalMilliseconds + "ms");
            textBox1.Text = sb.ToString();
        }

        /// <summary>
        /// 90
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button3_Click(object sender, EventArgs e)
        {
            if (bmp==null)
            {
                return;
            }

            var mat = OpenCvSharp.Extensions.BitmapConverter.ToMat(bmp);
            Cv2.CvtColor(mat, mat, ColorConversionCodes.RGBA2RGB);
            Cv2.Rotate(mat, mat, RotateFlags.Rotate90Clockwise);
            var bitmap = OpenCvSharp.Extensions.BitmapConverter.ToBitmap(mat);
            pictureBox1.Image = bitmap;
        }

        /// <summary>
        /// 180
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button4_Click(object sender, EventArgs e)
        {

            if (bmp == null)
            {
                return;
            }

            var mat = OpenCvSharp.Extensions.BitmapConverter.ToMat(bmp);
            Cv2.CvtColor(mat, mat, ColorConversionCodes.RGBA2RGB);
            Cv2.Rotate(mat, mat, RotateFlags.Rotate180);
            var bitmap = OpenCvSharp.Extensions.BitmapConverter.ToBitmap(mat);
            pictureBox1.Image = bitmap;
        }

        /// <summary>
        /// 270
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button5_Click(object sender, EventArgs e)
        {
            if (bmp == null)
            {
                return;
            }

            var mat = OpenCvSharp.Extensions.BitmapConverter.ToMat(bmp);
            Cv2.CvtColor(mat, mat, ColorConversionCodes.RGBA2RGB);
            Cv2.Rotate(mat, mat, RotateFlags.Rotate90Counterclockwise);
            var bitmap = OpenCvSharp.Extensions.BitmapConverter.ToBitmap(mat);
            pictureBox1.Image = bitmap;
        }
    }
}

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