PDFOffice_Windows_exe/PDF Office/ViewModels/Scan/ScanViwerViewModel.cs

using ComDocumentAIKit;
using ComPDFKit.PDFDocument;
using ComPDFKit.PDFPage;
using ComPDFKitViewer;
using ComPDFKitViewer.PdfViewer;
using PDF_Office.EventAggregators;
using PDF_Office.Helper;
using PDF_Office.Model;
using Prism.Events;
using Prism.Mvvm;
using Prism.Regions;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Imaging;

namespace PDF_Office.ViewModels.Scan
{
    class ScanViwerViewModel : BindableBase, INavigationAware
    {
        private CPDFViewer PDFViewer;

        private WriteableBitmap bgImage;

        public WriteableBitmap BgImage
        {
            get { return bgImage; }
            set
            {
                SetProperty(ref bgImage, value);
            }
        }

        private List<KeyValuePair<Rect, string>> textRectList;

        public List<KeyValuePair<Rect, string>> TextRectList
        {
            get { return textRectList; }
            set
            {
                SetProperty(ref textRectList, value);
            }
        }

        private Dictionary<int, List<KeyValuePair<Rect, string>>> cacahe;


        public bool IsNavigationTarget(NavigationContext navigationContext)
        {
            return true;
        }

        public void OnNavigatedFrom(NavigationContext navigationContext)
        {
            return;
        }

        public void OnNavigatedTo(NavigationContext navigationContext)
        {
            navigationContext.Parameters.TryGetValue<CPDFViewer>(ParameterNames.PDFViewer, out PDFViewer);
            if (PDFViewer == null)
            {
                return;
            }
            else
            {
                PDFViewer.InfoChanged += PDFViewer_InfoChanged;

                PDFViewer.ChangeViewMode(ViewMode.Single);
                //第一次进入获取当前预览显示内容
                CPDFPage pdfPage = PDFViewer.Document.PageAtIndex(PDFViewer.CurrentIndex);
                float zoom = (float)(DpiHelpers.Dpi / 72D);
                int renderWidth = (int)(pdfPage.PageSize.Width * zoom);
                int renderHeight = (int)(pdfPage.PageSize.Height * zoom);
                byte[] renderData = new byte[renderWidth * renderHeight * 4];
                pdfPage.RenderPageBitmapWithMatrix(zoom, new Rect(0, 0, renderWidth, renderHeight), 0xFFFFFFFF, renderData, 0);
                BgImage = new WriteableBitmap(renderWidth, renderHeight, DpiHelpers.Dpi, DpiHelpers.Dpi, PixelFormats.Bgra32, null);
                BgImage.WritePixels(new Int32Rect(0, 0, renderWidth, renderHeight), renderData, BgImage.BackBufferStride, 0);
            }
        }

        private void PDFViewer_InfoChanged(object sender, KeyValuePair<string, object> e)
        {
            if (e.Key == "PageNum")
            {
                RenderData renderData = e.Value as RenderData;
                if (renderData != null)
                {
                    CPDFPage pdfPage = PDFViewer.Document.PageAtIndex(renderData.PageIndex - 1);
                    float zoom = (float)(DpiHelpers.Dpi / 72D);
                    int renderWidth = (int)(pdfPage.PageSize.Width * zoom);
                    int renderHeight = (int)(pdfPage.PageSize.Height * zoom);
                    byte[] Data = new byte[renderWidth * renderHeight * 4];
                    pdfPage.RenderPageBitmapWithMatrix(zoom, new Rect(0, 0, renderWidth, renderHeight), 0xFFFFFFFF, Data, 0);
                    BgImage = new WriteableBitmap(renderWidth, renderHeight, DpiHelpers.Dpi, DpiHelpers.Dpi, PixelFormats.Bgra32, null);
                    BgImage.WritePixels(new Int32Rect(0, 0, renderWidth, renderHeight), Data, BgImage.BackBufferStride, 0);

                    if (cacahe.Count > 0)
                    {
                        if (cacahe.ContainsKey(renderData.PageIndex - 1))
                        {
                            TextRectList = cacahe[renderData.PageIndex - 1];
                        }
                        else
                        {
                            TextRectList = null;
                        }
                    }
                }
            }
        }

        public ScanViwerViewModel(IEventAggregator eventAggregator)
        {
            eventAggregator.GetEvent<ScanEvent>().Subscribe(ChangeScanMode, e => e.Unicode == App.mainWindowViewModel.SelectedItem.Unicode);
            cacahe = new Dictionary<int, List<KeyValuePair<Rect, string>>>();
        }
        /// <summary>
        /// 根据Vm事件通知处理OCR与区域识别事件
        /// </summary>
        /// <param name="e"></param>
        private void ChangeScanMode(ScanEventArgs e)
        {
            switch (e.Mode)
            {
                case ScanMode.Unknown:
                    break;
                case ScanMode.OCR:
                    OCRProcess(e);
                    break;
                case ScanMode.Area:
                    break;
                default:
                    break;
            }
        }

        private void OCRProcess(ScanEventArgs args)
        {
            COCREngine imEngine = new COCREngine(App.modelFolderPath);
            //CIMEngine imEngine = new CIMEngine(App.modelFolderPath);

            string path = App.CachePath.MergeFilePath;
            string name = Guid.NewGuid().ToString();
            path = Path.Combine(path, name);
            string EnhancePath = Path.Combine(path, "Enhance");

            Directory.CreateDirectory(path);
            Directory.CreateDirectory(EnhancePath);

            CPDFDocument CurrentDoc = PDFViewer.Document;

            CErrorCode error = imEngine.SetModel((COCRLanguage)args.ScanLanguage);

            cacahe.Clear();

            for (int i = 0; i < args.PageRange.Count; i++)
            {
                string pageImagePath = Path.Combine(path, args.PageRange[i].ToString());
                string pageEnhancePath = Path.Combine(EnhancePath, args.PageRange[i].ToString() + ".png");

                CPDFPage pdfPage = CurrentDoc.PageAtIndex(args.PageRange[i]);
                float zoom = (float)(DpiHelpers.Dpi / 72D);
                int renderWidth = (int)(pdfPage.PageSize.Width * zoom);
                int renderHeight = (int)(pdfPage.PageSize.Height * zoom);
                byte[] renderData = new byte[renderWidth * renderHeight * 4];
                pdfPage.RenderPageBitmapWithMatrix(zoom, new Rect(0, 0, renderWidth, renderHeight), 0xFFFFFFFF, renderData, 0);
                WriteableBitmap bitmap = new WriteableBitmap(renderWidth, renderHeight, DpiHelpers.Dpi, DpiHelpers.Dpi, PixelFormats.Bgra32, null);
                bitmap.WritePixels(new Int32Rect(0, 0, renderWidth, renderHeight), renderData, bitmap.BackBufferStride, 0);
                BitmapEncoder encoder = new PngBitmapEncoder();
                encoder.Frames.Add(BitmapFrame.Create(bitmap));

                using (FileStream imageStream = File.Create(pageImagePath))
                {
                    encoder.Save(imageStream);
                    imageStream.Flush();
                }

                //File.Create(pageEnhancePath);
                //error = imEngine.Process(pageImagePath, pageEnhancePath);
                error = imEngine.Process(pageImagePath);

                if (imEngine.OCRResultList == null)
                    return;

                List<KeyValuePair<Rect, string>> RectList = new List<KeyValuePair<Rect, string>>();
                foreach (COCRResult ocrResult in imEngine.OCRResultList)
                {
                    List<Point> rectPoints = new List<Point>();
                    for (int j = 0; j < ocrResult.position.Length; j += 2)
                    {
                        rectPoints.Add(new Point(ocrResult.position[j], ocrResult.position[j + 1]));
                    }
                    int left = (int)rectPoints.AsEnumerable().Min(x => x.X);
                    int right = (int)rectPoints.AsEnumerable().Max(x => x.X);
                    int top = (int)rectPoints.AsEnumerable().Min(x => x.Y);
                    int bottom = (int)rectPoints.AsEnumerable().Max(x => x.Y);

                    RectList.Add(new KeyValuePair<Rect, string>(new Rect(left, top, right - left, bottom - top), ocrResult.text));
                }
                cacahe.Add(args.PageRange[i], RectList);
            }
            if (cacahe.Count > 0)
            {
                if (cacahe.ContainsKey(PDFViewer.CurrentIndex))
                {
                    TextRectList = cacahe[PDFViewer.CurrentIndex];
                }
                else
                {
                    TextRectList = null;
                }
            }
            imEngine.Release();
        }
    }
}