效果

项目

VS2022+.net4.8+OCRV4

代码

using OpenCvSharp;
using Sdcb.PaddleInference;
using Sdcb.PaddleOCR;
using Sdcb.PaddleOCR.Models;
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 PaddleInference.OCRServiceV4
{
    public partial class frmTest : Form
    {
        public frmTest()
        {
            InitializeComponent();
        }

        String startupPath;
        public PaddleOcrAll paddleOcr;
        private string fileFilter = "*.*|*.bmp;*.jpg;*.jpeg;*.tiff;*.tiff;*.png";
        Bitmap bmp;
        PaddleOcrResult ocrResult;
        DateTime dt1 = DateTime.Now;
        DateTime dt2 = DateTime.Now;
        String imgPath;
        Mat mat;
        Pen pen = new Pen(Brushes.Red, 2);

        private void frmTest_Load(object sender, EventArgs e)
        {
            comboBox1.SelectedIndex = 0;
            startupPath = Application.StartupPath;
            rbOnnx.Checked = true;
        }

        private void btnLoadModel_Click(object sender, EventArgs e)
        {
            LoadModel();
            MessageBox.Show("加载完成");
        }

        void LoadModel()
        {
            string detectionModelDir;
            string classificationModelDir;
            string recognitionModelDir;
            string labelFilePath;

            if (comboBox1.SelectedIndex == 0)
            {
                detectionModelDir = startupPath + "\\inference\\ch_PP-OCRv4_det_infer";
                classificationModelDir = startupPath + "\\inference\\ch_ppocr_mobile_v2.0_cls_infer";
                recognitionModelDir = startupPath + "\\inference\\ch_PP-OCRv4_rec_infer";
                labelFilePath = startupPath + "\\inference\\ppocr_keys.txt";
            }
            else
            {
                detectionModelDir = startupPath + "\\inference_server\\detv4_teacher_inference";
                classificationModelDir = startupPath + "\\inference_server\\ch_ppocr_mobile_v2.0_cls_infer";
                recognitionModelDir = startupPath + "\\inference_server\\ch_PP-OCRv4_rec_server_infer";
                labelFilePath = startupPath + "\\inference_server\\ppocr_keys.txt";
            }

            FullOcrModel model = FullOcrModel.FromDirectory(detectionModelDir, classificationModelDir, recognitionModelDir, labelFilePath, ModelVersion.V4);

            if (rbOnnx.Enabled == true)
            {
                paddleOcr = new PaddleOcrAll(model, PaddleDevice.Onnx());
            }

            else if (rbOpenblas.Enabled == true)
            {
                paddleOcr = new PaddleOcrAll(model, PaddleDevice.Openblas());
            }

            else if (rbMkldnn.Enabled == true)
            {
                paddleOcr = new PaddleOcrAll(model, PaddleDevice.Mkldnn());
            }
            else
            {
                paddleOcr = new PaddleOcrAll(model);
            }

            paddleOcr.AllowRotateDetection = true;    /* 允许识别有角度的文字 */
            paddleOcr.Enable180Classification = false; /* 允许识别旋转角度大于90度的文字 */
        }


        private void btnSelect_Click(object sender, EventArgs e)
        {
            if (paddleOcr == null)
            {
                MessageBox.Show("请先加载模型");
                return;
            }


            OpenFileDialog ofd = new OpenFileDialog();
            ofd.Filter = fileFilter;
            if (ofd.ShowDialog() != DialogResult.OK) return;

            imgPath = ofd.FileName;
            bmp = new Bitmap(imgPath, true);

            RotateImage(bmp);

            pictureBox1.Image = bmp;

            richTextBox1.Clear();

            mat = new Mat(ofd.FileName);
            //pictureBox1.Image = OpenCvSharp.Extensions.BitmapConverter.ToBitmap(mat);


            dt1 = DateTime.Now;
            ocrResult = paddleOcr.Run(mat);
            dt2 = DateTime.Now;


            ShowOCRResult(ocrResult);

        }

        /// <summary>
        /// 显示结果
        /// </summary>
        private void ShowOCRResult(PaddleOcrResult ocrResult)
        {

            richTextBox1.Clear();
            Bitmap bitmap = (Bitmap)this.pictureBox1.Image;


            richTextBox1.AppendText("耗时:" + (dt2 - dt1).TotalMilliseconds + "ms\n");
            richTextBox1.AppendText("-----------------------------------\n");
            richTextBox1.AppendText(ocrResult.Text + "\n");

            using (Graphics g = Graphics.FromImage(bitmap))
            {
                foreach (var item in ocrResult.Regions)
                {
                    g.DrawRectangle(pen, item.Rect.BoundingRect().Left, item.Rect.BoundingRect().Top, item.Rect.BoundingRect().Width, item.Rect.BoundingRect().Height);
                }
            }

            pictureBox1.Image = null;
            pictureBox1.Image = bitmap;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (paddleOcr == null)
            {
                MessageBox.Show("请先加载模型");
                return;
            }

            if (pictureBox1.Image == null)
            {
                return;
            }
            richTextBox1.Clear();
            Application.DoEvents();

            dt1 = DateTime.Now;
            ocrResult = paddleOcr.Run(mat);
            dt2 = DateTime.Now;

            ShowOCRResult(ocrResult);
        }

        /// <summary>
        /// 根据图片exif调整方向
        /// </summary>
        /// <param name="img"></param>
        public void RotateImage(Bitmap img)
        {
            var exif = img.PropertyItems;
            byte orien = 0;
            var item = exif.Where(m => m.Id == 274).ToArray();
            if (item.Length > 0)
                orien = item[0].Value[0];
            switch (orien)
            {
                case 2:
                    img.RotateFlip(RotateFlipType.RotateNoneFlipX);//horizontal flip
                    break;
                case 3:
                    img.RotateFlip(RotateFlipType.Rotate180FlipNone);//right-top
                    break;
                case 4:
                    img.RotateFlip(RotateFlipType.RotateNoneFlipY);//vertical flip
                    break;
                case 5:
                    img.RotateFlip(RotateFlipType.Rotate90FlipX);
                    break;
                case 6:
                    img.RotateFlip(RotateFlipType.Rotate90FlipNone);//right-top
                    break;
                case 7:
                    img.RotateFlip(RotateFlipType.Rotate270FlipX);
                    break;
                case 8:
                    img.RotateFlip(RotateFlipType.Rotate270FlipNone);//left-bottom
                    break;
                default:
                    break;
            }
        }

    }
}

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