mirror of
https://github.com/wmjordan/PDFPatcher.git
synced 2026-10-18 13:42:28 +08:00
WMJ
749 lines
26 KiB
C#
749 lines
26 KiB
C#
using System;
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using System.Collections.Generic;
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using System.Xml;
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using iTextSharp.text;
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using iTextSharp.text.pdf;
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using iTextSharp.text.pdf.parser;
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using PDFPatcher.Common;
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using PDFPatcher.Model;
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namespace PDFPatcher.Processor
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{
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sealed class AutoBookmarkCreator
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{
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sealed class SizeOccurrence(float size, int page, string instance)
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{
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public float Size { get; set; } = size;
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public int FirstPage { get; set; } = page;
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public string FirstInstance { get; set; } = instance.Length > 50 ? instance.Substring(0, 50) : instance;
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public int Occurrence { get; set; } = 1;
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}
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sealed class FontOccurrence
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{
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readonly Dictionary<string, List<SizeOccurrence>> oc = [];
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internal List<SizeOccurrence> GetOccurrence(string fontName) {
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return oc.TryGetValue(fontName, out List<SizeOccurrence> s) ? s : null;
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}
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internal void AddOccurrence(string fontName, float size, int page, string instance) {
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if (!oc.ContainsKey(fontName)) {
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oc.Add(fontName, [new SizeOccurrence(size, page, instance)]);
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}
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else {
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var o = oc[fontName].Find((s) => s.Size == size);
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if (o != null) {
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o.Occurrence++;
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}
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else {
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oc[fontName].Add(new SizeOccurrence(size, page, instance));
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}
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}
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}
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}
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const string __AddSpaceAfterCharacters = ":.,\"'?!)]};";
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const string __InsertSpaceBeforeCharacters = "\"'([{";
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readonly PdfReader _reader;
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readonly AutoBookmarkOptions _options;
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const int OpenWorkload = 10;
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public AutoBookmarkCreator(PdfReader reader, AutoBookmarkOptions options) {
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_reader = reader;
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_options = options;
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TextLine.DefaultDirection = options.WritingDirection;
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}
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internal int EstimateWorkload() {
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var n = _reader.NumberOfPages;
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var load = 0;
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load += OpenWorkload;
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var t = PageRangeCollection.Parse(_options.PageRanges, 1, n, true).TotalPages;
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load += t > 0 ? t : n;
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return load;
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}
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internal void ExportAutoBookmarks(XmlWriter w, AutoBookmarkOptions options) {
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AutoCreateBookmarks(w, _reader, options);
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}
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internal void AutoCreateBookmarks(XmlWriter writer, PdfReader reader, AutoBookmarkOptions options) {
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Tracker.IncrementProgress(OpenWorkload);
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int pn = reader.NumberOfPages + 1;
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var c = new AutoBookmarkContext() { TotalPageNumber = reader.NumberOfPages };
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var p = new TextToBookmarkProcessor(options, c);
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var lp = new LevelProcessor(options.LevelAdjustment);
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var ranges = PageRangeCollection.Parse(options.PageRanges, 1, reader.NumberOfPages, true);
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var doc = new XmlDocument();
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var be = doc.AppendChild(doc.CreateElement(Constants.Bookmark)) as XmlElement;
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float size = -1;
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var sizes = new Stack<float>();
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float yOffset = 1 + options.YOffset;
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int level = 0;
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const string indentString = " ";
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List<MatchPattern.IMatcher> ig;
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var fontOccurrences = new FontOccurrence();
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if (options.IgnorePatterns.Count == 0) {
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ig = null;
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}
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else {
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ig = [];
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foreach (var item in options.IgnorePatterns) {
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if (String.IsNullOrEmpty(item.Text)) {
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continue;
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}
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try {
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ig.Add(item.CreateMatcher());
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}
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catch (ArgumentException ex) {
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Tracker.TraceMessage(Tracker.Category.Alert, (String.Concat("忽略文本（", item, "）无效：", ex.Message)));
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}
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}
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}
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XmlWriter oldWriter = null;
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if (!options.ExportTextCoordinates) {
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oldWriter = writer;
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writer = new NullXmlWriter();
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}
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foreach (PageRange r in ranges) {
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for (int i = r.StartValue; i <= r.EndValue && i < pn; i++) {
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if (i == 1 && options.CreateBookmarkForFirstPage) {
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continue;
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}
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//Tracker.TraceMessage (String.Concat ("分析第 ", i, " 页。"));
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var box = reader.GetCropBox(i);
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p.Reset();
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c.PageBox = box;
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c.CurrentPageNumber = i;
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var pr = reader.GetPageRotation(i);
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pr = PdfHelper.NormalizeRotationNumber(pr);
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if (pr != 0) {
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p.RotationMatrix = pr switch {
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90 => new Matrix(0, 1, -1, 0, 0, 0),
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180 => new Matrix(0, -1, -1, 0, 0, 0),
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270 => new Matrix(0, -1, 1, 0, 0, 0),
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_ => p.RotationMatrix
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};
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}
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p.ProcessContent(reader.GetPageContent(i), reader.GetPageNRelease(i).GetAsDict(PdfName.RESOURCES));
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c.IsTextMerged = false;
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c.TextLine = null;
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// TODO: 自动根据已知排版方向比例修正排版方向
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// 合并前筛选文本
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var ptl = p.TextList;
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for (int li = ptl.Count - 1; li >= 0; li--) {
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c.TextInfo = ptl[li];
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if (lp.ChangeSizeLevel(c) < options.TitleThreshold) {
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ptl.RemoveAt(li);
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}
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}
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var tl = MergeTextInfoList(box, ptl, _options);
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// TODO: 筛选文本
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c.IsTextMerged = true;
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for (int li = tl.Count - 1; li >= 0; li--) {
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c.TextLine = tl[li];
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c.TextInfo = c.TextLine.FirstText;
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if ((c.TextInfo.Size = lp.ChangeSizeLevel(c)) < options.TitleThreshold) {
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tl.RemoveAt(li);
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}
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}
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var tr = MergeTextLines(box, tl);
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if (tr != null && tr.Count > 0) {
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if (options.WritingDirection != WritingDirection.Unknown) {
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tr.Sort((a, b) => {
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var ra = a.Region;
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var rb = b.Region;
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if (ra.Middle < rb.Middle) return 1;
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else if (ra.Middle > rb.Middle) return -1;
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else if (ra.Center > rb.Center) return 1;
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else if (ra.Center < rb.Center) return -1;
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else return 0;
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});
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}
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writer.WriteStartElement(Constants.Content.Texts);
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writer.WriteValue(Constants.Content.PageNumber, i);
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foreach (var item in tr) {
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var t = PdfHelper.GetValidXmlString(ConcatRegionText(item)).Trim();
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var f = item.Lines[0].FirstText.Font;
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var s = item.Lines[0].FirstText.Size;
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writer.WriteStartElement("文本");
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writer.WriteAttributeString(Constants.Font.ThisName, f != null ? f.FontID.ToText() : "OCR");
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writer.WriteValue(Constants.Coordinates.Top, item.Region.Top);
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writer.WriteValue(Constants.Coordinates.Bottom, item.Region.Bottom);
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writer.WriteValue(Constants.Coordinates.Left, item.Region.Left);
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writer.WriteValue(Constants.Coordinates.Width, item.Region.Width);
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writer.WriteValue(Constants.Coordinates.Height, item.Region.Height);
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writer.WriteValue("尺寸", s);
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writer.WriteString(t);
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writer.WriteEndElement();
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if (t.Length == 0
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|| (t.Length == 1 && options.IgnoreSingleCharacterTitle)
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|| (options.IgnoreNumericTitle && AutoBookmarkOptions.NumericPattern.IsMatch(t))
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) {
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continue;
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}
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if (ig != null) {
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bool ignore = false;
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foreach (var rg in ig) {
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if (rg.Matches(t)) {
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ignore = true;
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continue;
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}
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}
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if (ignore) {
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continue;
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}
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}
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if (options.AutoHierarchicalArrangement) {
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do {
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if (sizes.Count == 0 || s < (size = sizes.Peek())) {
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be = be.AppendChild(doc.CreateElement(Constants.Bookmark)) as XmlElement;
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sizes.Push(s);
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level++;
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break;
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}
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else if (s == size) {
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be = (be.ParentNode ?? be).AppendChild(doc.CreateElement(Constants.Bookmark)) as XmlElement;
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break;
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}
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be = be.ParentNode as XmlElement;
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sizes.Pop();
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level--;
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} while (s > size && be.NodeType == XmlNodeType.Element);
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}
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else {
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be = doc.DocumentElement.AppendChild(doc.CreateElement(Constants.Bookmark)) as XmlElement;
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}
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be.SetAttribute(Constants.BookmarkAttributes.Title, t);
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be.SetAttribute(Constants.DestinationAttributes.Page, i.ToText());
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be.SetAttribute(Constants.DestinationAttributes.View, Constants.DestinationAttributes.ViewType.XYZ);
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be.SetAttribute(Constants.Coordinates.Top, ValueHelper.ToText(item.Region.Top + s * yOffset));
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be.SetAttribute(Constants.Font.Size, s.ToText());
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if (f != null) {
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be.SetAttribute(Constants.Font.ThisName, f.FontID.ToText());
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}
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CountFontOccurrenceInRegion(fontOccurrences, i, item);
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#if DEBUG
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Tracker.TraceMessage(String.Concat(item.Direction.ToString()[0], ':', level < 11 ? indentString.Substring(0, level) : indentString, t, " .... ", i.ToText()));
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#else
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Tracker.TraceMessage (String.Concat (level < 11 ? indentString.Substring (0, level) : indentString, t, " .... ", ValueHelper.ToText (i)));
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#endif
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}
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writer.WriteEndElement();
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}
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Tracker.IncrementProgress(1);
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}
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}
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if (oldWriter != null) {
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writer = oldWriter;
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}
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WriteDocumentFontOccurrences(writer, options, p, fontOccurrences);
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SetGoToTop(options, doc);
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writer.WriteStartElement(Constants.DocumentBookmark);
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if (options.CreateBookmarkForFirstPage && !String.IsNullOrEmpty(options.FirstPageTitle)) {
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writer.WriteStartElement(Constants.Bookmark);
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writer.WriteAttributeString(Constants.BookmarkAttributes.Title, options.FirstPageTitle);
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writer.WriteAttributeString(Constants.DestinationAttributes.Page, "1");
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writer.WriteAttributeString(Constants.DestinationAttributes.Action, Constants.ActionType.Goto);
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writer.WriteEndElement();
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}
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doc.DocumentElement.WriteContentTo(writer);
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writer.WriteEndElement();
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}
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static void SetGoToTop(AutoBookmarkOptions options, XmlDocument doc) {
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if (options.PageTopForLevel > 0) {
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var topics = doc.DocumentElement.SelectNodes(".//书签[count(ancestor::书签) < " + (options.PageTopForLevel + 1) + "]");
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foreach (XmlElement t in topics) {
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t.RemoveAttribute(Constants.Coordinates.Top);
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}
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}
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}
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static void WriteDocumentFontOccurrences(XmlWriter writer, AutoBookmarkOptions options, TextToBookmarkProcessor p, FontOccurrence fontOccurrences) {
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writer.WriteStartElement(Constants.Font.DocumentFont);
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Tracker.TraceMessage("\n文档所用的字体");
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var dl = new List<String>();
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foreach (var item in p.FontList) {
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var fo = "0";
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var sl = fontOccurrences.GetOccurrence(item.Value);
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if (sl != null) {
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if (!dl.Contains(item.Value)) {
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int o = 0;
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foreach (var s in sl) {
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o += s.Occurrence;
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}
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fo = o.ToText();
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dl.Add(item.Value);
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}
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else {
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sl = null;
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}
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}
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if (options.DisplayFontStatistics && (sl != null || options.DisplayAllFonts)) {
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Tracker.TraceMessage(String.Concat("编号：", item.Key, "\t出现次数：", fo, "\t名称：", item.Value));
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}
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writer.WriteStartElement(Constants.Font.ThisName);
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writer.WriteAttributeString(Constants.Font.ID, item.Key.ToText());
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writer.WriteAttributeString(Constants.Font.Name, item.Value);
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writer.WriteAttributeString(Constants.FontOccurrence.Count, fo);
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if (sl != null) {
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foreach (var s in sl) {
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writer.WriteStartElement(Constants.Font.Size);
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writer.WriteAttributeString(Constants.Font.Size, s.Size.ToText());
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writer.WriteAttributeString(Constants.FontOccurrence.Count, s.Occurrence.ToText());
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writer.WriteAttributeString(Constants.FontOccurrence.FirstText, s.FirstInstance);
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writer.WriteAttributeString(Constants.FontOccurrence.FirstPage, s.FirstPage.ToText());
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if (options.DisplayFontStatistics && (s.Occurrence > 0 || options.DisplayAllFonts)) {
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Tracker.TraceMessage($"\t尺寸：{s.Size.ToText()}\t出现次数：{s.Occurrence.ToText()}\t首次出现于第{s.FirstPage.ToText()}页（{s.FirstInstance}）");
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}
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writer.WriteEndElement();
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}
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}
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writer.WriteEndElement();
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}
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writer.WriteEndElement();
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}
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static void CountFontOccurrenceInRegion(FontOccurrence fontOccurrences, int i, TextRegion item) {
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FontInfo f = null;
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foreach (var il in item.Lines) {
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foreach (var ii in il.Texts) {
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if (ii.Font != null && (f == null || ii.Font.FontID != f.FontID)) {
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fontOccurrences.AddOccurrence(ii.Font.FontName, ii.Size, i, il.Text);
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f = ii.Font;
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}
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}
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}
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}
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static string ConcatRegionText(TextRegion region) {
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var ls = region.Lines;
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if (ls.Count == 0) {
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return String.Empty;
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}
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else if (ls.Count == 1) {
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return ls[0].Text;
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}
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ls = new List<TextLine>(ls);
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if (region.Direction == WritingDirection.Vertical) {
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ls.Sort((a, b) => {
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if (a.Region.Middle < b.Region.Middle) {
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return 1;
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}
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if (a.Region.Middle > b.Region.Middle) {
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return -1;
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}
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return 0;
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});
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}
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var sb = StringBuilderCache.Acquire();
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sb.Append(ls[0].Text);
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for (int i = 1; i < ls.Count; i++) {
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var l = ls[i].Text;
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var ll = ls[i - 1].Text;
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if (ll.Length > 0 && l.Length > 0) {
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var c1 = l[l.Length - 1];
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var c2 = ll[0];
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if ((__AddSpaceAfterCharacters.IndexOf(c1) != -1
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|| (Char.IsLetterOrDigit(c1) && c1 < 0x4E00 /*非中文字符*/))
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&& (__InsertSpaceBeforeCharacters.IndexOf(c2) != -1
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|| (Char.IsLetterOrDigit(c2) && c2 < 0x4E00))) {
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sb.Append(' ');
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}
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}
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sb.Append(l);
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}
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return StringBuilderCache.GetStringAndRelease(sb);
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}
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/// <summary>
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/// 使用最小距离法将 <paramref name="textInfos"/> 的文本聚类为 <see cref="TextLine"/> 列表。
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/// </summary>
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/// <param name="textInfos">包含文本位置及尺寸信息的 <see cref="TextInfo"/> 集合。</param>
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/// <returns>聚类后所得的 <see cref="TextLine"/> 列表。</returns>
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internal static List<TextLine> MergeTextInfoList(Rectangle pageBox, IList<TextInfo> textInfos, AutoBookmarkOptions options) {
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var ll = new List<TextLine>();
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// 同行合并宽度最小值
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var cw = pageBox.Width / 6;
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var ch = pageBox.Height / 6;
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var dirCount = new int[4];
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// 遍历识别所得的各 TextInfo，使用最小距离聚类方法将其聚类为行
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foreach (var item in textInfos) {
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var ir = item.Region;
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DistanceInfo cd = null; // TextInfo 到 TextLine 的距离
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var md = new DistanceInfo(DistanceInfo.Placement.Unknown, float.MaxValue, float.MaxValue); // 最小距离
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TextLine ml = null; // 最小距离的 TextLine
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// 求最小距离的 TextLine
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float ds = item.Size / 10;
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// 循环只包含了 TextLine，未包含文本 TextInfo 的其余文本
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var end = ll.Count > 5 ? ll.Count - 5 : 0;
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for (int i = ll.Count - 1; i >= end; i--) {
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var li = ll[i];
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// 文本尺寸应在误差范围之内
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if (Math.Abs(item.Size - li.FirstText.Size) > ds && !options.MergeDifferentSizeTitles) {
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continue;
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}
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if (!options.MergeDifferentFontTitles && li.FirstText.Font.FontID != item.Font.FontID) {
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break;
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}
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cd = li.GetDistance(ir);
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if ((cd.IsOverlapping // 当前项与文本行交叠
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&& (!md.IsOverlapping // 最小距离不是交叠
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|| cd.DistanceRadial < md.DistanceRadial) // 当前项与文本行的交叠中心距离小于最小距离
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)
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//&& (options.MergeDifferentFontTitles || li.FirstText.Font.FontID == item.Font.FontID)
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|| ((md.Location == DistanceInfo.Placement.Unknown // 未知最小距离
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|| (!cd.IsOverlapping
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&& !md.IsOverlapping
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&& cd.MinDistance < md.MinDistance) // 当前项与文本行的距离小于最小距离
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)
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&& (((cd.IsHorizontallyAligned) // 相对位置为水平
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&& li.Direction != WritingDirection.Vertical // 文本行方向不为纵向
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&& item.Region.IsAlignedWith(li.Region, WritingDirection.Horizontal) // 两者处于同一横行
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)
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|| ((cd.IsVerticallyAligned) // 相对位置为垂直
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&& li.Direction != WritingDirection.Horizontal // 文本行方向不为横向
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&& item.Region.IsAlignedWith(li.Region, WritingDirection.Vertical) // 两者处于同一纵行
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// && Math.Abs (item.Region.Middle - li.Region.Middle) < li.Region.Height // 行间距离小于行高
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)
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)
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&& (!options.DetectColumns || cd.MinDistance < cw)
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&& (options.MergeDifferentFontTitles || li.FirstText.Font.FontID == item.Font.FontID)
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)
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) {
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md = cd;
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ml = li;
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if (cd.IsLeft) {
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dirCount[0]++;
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}
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else if (cd.IsRight) {
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dirCount[1]++;
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}
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else if (cd.IsAbove) {
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dirCount[2]++;
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}
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else if (cd.IsBelow) {
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dirCount[3]++;
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}
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}
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}
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// 否则，用 item 创建新的 TextLine
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if (item.Text.Length == 0) {
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item.Text = " ";
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}
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if (ml != null) {
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// 若存在最小距离的 TextLine 且可合并，则将 item 归入 TextLine
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||
if (md.IsOverlapping && options.IgnoreOverlappedText) {
|
||
// 检查是否存在交叠重复的文本
|
||
foreach (var t in ml.Texts) {
|
||
if (t.Region.IntersectWith(item.Region) // item 与 TextLine 中某项交叠
|
||
&& (t.Text.Contains(item.Text) || item.Text.Contains(t.Text) // 交叠的项文本和 item 的文本相同
|
||
)
|
||
) {
|
||
goto Next; // 忽略此项目
|
||
}
|
||
}
|
||
}
|
||
ml.AddText(item);
|
||
}
|
||
else {
|
||
ll.Add(new TextLine(item));
|
||
}
|
||
Next:
|
||
continue;
|
||
}
|
||
return ll;
|
||
}
|
||
|
||
internal List<TextRegion> MergeTextLines(Rectangle pageBox, IList<TextLine> textLines) {
|
||
var ll = new List<TextRegion>();
|
||
// 同行合并宽度最小值
|
||
var cw = pageBox.Width / 6;
|
||
var ch = pageBox.Height / 6;
|
||
|
||
// 遍历识别所得的各 TextInfo，使用最小距离聚类方法将其聚类为行
|
||
foreach (var item in textLines) {
|
||
var ir = item.Region;
|
||
DistanceInfo cd = null; // TextInfo 到 TextLine 的距离
|
||
var md = new DistanceInfo(DistanceInfo.Placement.Unknown, float.MaxValue, float.MaxValue); // 最小距离
|
||
TextRegion mr = null; // 最小距离的 TextRegion
|
||
|
||
// 求最小距离的 TextLine
|
||
float ds = item.FirstText.Size / 10;
|
||
// 循环只包含了 TextLine，未包含文本 TextInfo 的其余文本
|
||
for (int i = ll.Count - 1; i >= 0; i--) {
|
||
var li = ll[i];
|
||
// 文本尺寸应在误差范围之内
|
||
if (Math.Abs(item.FirstText.Size - li.Lines[0].FirstText.Size) > ds && _options.MergeAdjacentTitles) {
|
||
continue;
|
||
}
|
||
if (!_options.MergeDifferentFontTitles && li.Lines[0].FirstText.Font.FontID != item.FirstText.Font.FontID) {
|
||
break;
|
||
}
|
||
cd = li.Region.GetDistance(ir, li.Direction);
|
||
if ((cd.IsOverlapping // 当前项与文本行交叠
|
||
&& (!md.IsOverlapping // 最小距离不是交叠
|
||
|| cd.DistanceRadial < md.DistanceRadial) // 当前项与文本行的交叠中心距离小于最小距离
|
||
)
|
||
|| ((md.Location == DistanceInfo.Placement.Unknown // 未知最小距离
|
||
|| (!cd.IsOverlapping
|
||
&& !md.IsOverlapping
|
||
&& cd.MinDistance < md.MinDistance) // 当前项与文本行的距离小于最小距离
|
||
)
|
||
&& (((cd.IsHorizontallyAligned) // 相对位置为水平
|
||
&& li.Direction != WritingDirection.Vertical // 文本行方向不为纵向
|
||
&& item.Region.IsAlignedWith(li.Region, WritingDirection.Horizontal) // 两者处于同一横行
|
||
&& cd.MinDistance < item.Region.Width * _options.MaxDistanceBetweenLines // 行间距离小于指定行宽
|
||
&& _options.MergeAdjacentTitles
|
||
&& (_options.MergeDifferentSizeTitles || li.Lines[0].Region.Width == item.Region.Width) // 合并相同尺寸的标题
|
||
)
|
||
|| ((cd.IsVerticallyAligned) // 相对位置为垂直
|
||
&& li.Direction != WritingDirection.Horizontal // 文本行方向不为横向
|
||
&& item.Region.IsAlignedWith(li.Region, WritingDirection.Vertical) // 两者处于同一纵行
|
||
&& cd.MinDistance < item.Region.Height * _options.MaxDistanceBetweenLines // 行间距离小于指定行高
|
||
&& _options.MergeAdjacentTitles
|
||
&& (_options.MergeDifferentSizeTitles || li.Lines[0].Region.Height == item.Region.Height) // 合并相同尺寸的标题
|
||
)
|
||
)
|
||
&& cd.MinDistance < cw
|
||
)
|
||
) {
|
||
md = cd;
|
||
mr = li;
|
||
}
|
||
}
|
||
|
||
// 否则，用 item 创建新的 TextLine
|
||
if (mr != null) {
|
||
// 若存在最小距离的 TextLine 且可合并，则将 item 归入 TextLine
|
||
mr.AddLine(item);
|
||
}
|
||
else {
|
||
ll.Add(new TextRegion(item));
|
||
}
|
||
}
|
||
return ll;
|
||
}
|
||
|
||
sealed class TextToBookmarkProcessor : PdfContentStreamProcessor
|
||
{
|
||
readonly float _fontSizeThreshold;
|
||
|
||
//Rectangle _positionRectangle;
|
||
readonly bool _mergeAdjacentTitles;
|
||
readonly bool _mergeDifferentSizeTitles;
|
||
float _textWidth, _charWidth;
|
||
readonly List<TextInfo> _TextList;
|
||
readonly LevelProcessor _levelProcessor;
|
||
readonly AutoBookmarkContext _context;
|
||
|
||
public TextToBookmarkProcessor(AutoBookmarkOptions options, AutoBookmarkContext context) {
|
||
_fontSizeThreshold = options.TitleThreshold;
|
||
_mergeAdjacentTitles = options.MergeAdjacentTitles;
|
||
_mergeDifferentSizeTitles = options.MergeDifferentSizeTitles;
|
||
_levelProcessor = new LevelProcessor(options.LevelAdjustment);
|
||
_TextList = [];
|
||
PopulateOperators();
|
||
RegisterContentOperator("TJ", new AccumulatedShowTextArray());
|
||
_context = context;
|
||
}
|
||
|
||
/// <summary>
|
||
/// 获取页面内容的文本。
|
||
/// </summary>
|
||
internal List<TextInfo> TextList => _TextList;
|
||
/// <summary>
|
||
/// 获取字体列表。
|
||
/// </summary>
|
||
internal IDictionary<int, string> FontList => Fonts;
|
||
|
||
public Matrix RotationMatrix { get; set; }
|
||
|
||
internal override void Reset() {
|
||
base.Reset();
|
||
_TextList?.Clear();
|
||
}
|
||
|
||
protected override void DisplayPdfString(PdfString str) {
|
||
var gs = CurrentGraphicState;
|
||
var font = gs.Font;
|
||
var chars = font.DecodeText(str);
|
||
float totalWidth = 0, charWidth = 0;
|
||
foreach (var c in chars) {
|
||
float w = font.GetWidth(c) / 1000.0f;
|
||
if (w == 0 && (font.CjkType & FontInfo.CjkFontType.CJK) > 0) {
|
||
w = c < 0xFF ? 0.5f : 1f;
|
||
}
|
||
float wordSpacing = c == ' ' ? gs.WordSpacing : 0f;
|
||
if (Char.IsLetterOrDigit(c)) {
|
||
charWidth += w * gs.FontSize * gs.HorizontalScaling;
|
||
}
|
||
totalWidth += (w * gs.FontSize + gs.CharacterSpacing + wordSpacing) * gs.HorizontalScaling;
|
||
}
|
||
|
||
_textWidth = totalWidth;
|
||
_charWidth = charWidth;
|
||
AdjustTextMatrixX(totalWidth);
|
||
}
|
||
|
||
protected override void InvokeOperator(PdfLiteral oper, List<PdfObject> operands) {
|
||
var o = oper.ToString();
|
||
string text;
|
||
float size;
|
||
Matrix tm;
|
||
switch (o) {
|
||
case "TJ":
|
||
tm = GetTextMatrix();
|
||
size = GetFontSize(tm);
|
||
text = DecodeTJText(operands, size);
|
||
break;
|
||
case "Tj":
|
||
case "'":
|
||
case "\"":
|
||
tm = GetTextMatrix();
|
||
size = GetFontSize(tm);
|
||
if (size < 0) {
|
||
size = -size;
|
||
}
|
||
text = CurrentGraphicState.Font.DecodeText(operands[0] as PdfString);
|
||
break;
|
||
default:
|
||
// 执行默认的操作指令
|
||
base.InvokeOperator(oper, operands);
|
||
return;
|
||
}
|
||
|
||
// 处理文本
|
||
base.InvokeOperator(oper, operands);
|
||
//if (tm[Matrix.I12] != 0 || tm[Matrix.I21] != 0) {
|
||
// // 忽略非横向文本
|
||
// goto Exit;
|
||
//}
|
||
if (size < 0.0001) {
|
||
size = 0.0001f;
|
||
}
|
||
else {
|
||
size = (float)Math.Round(size, 4);
|
||
}
|
||
var ti = new TextInfo() {
|
||
Text = text.Length > 1 ? text.TrimEnd(' ') : text,
|
||
Size = size,
|
||
Region = CreateBoundFromMatrix(tm, _textWidth, size),
|
||
Font = CurrentGraphicState.Font,
|
||
LetterWidth = _charWidth * tm[Matrix.I22]
|
||
};
|
||
if (ti.LetterWidth < 0) {
|
||
ti.LetterWidth = -ti.LetterWidth;
|
||
}
|
||
if (IsBoundOutOfRectangle(_context.PageBox, ti.Region)) {
|
||
// 文本落在页面之外
|
||
goto Exit;
|
||
}
|
||
//TODO: 筛选文本
|
||
_TextList.Add(ti);
|
||
Exit:
|
||
return;
|
||
}
|
||
|
||
string DecodeTJText(List<PdfObject> operands, float size) {
|
||
var array = (PdfArray)operands[0];
|
||
float d = size * CurrentGraphicState.HorizontalScaling * 4f / 1000f;
|
||
var t = new string[array.Size];
|
||
int i = 0;
|
||
foreach (PdfObject item in array.ArrayList) {
|
||
if (item.Type == PdfObject.STRING) {
|
||
t[i++] = CurrentGraphicState.Font.DecodeText(item as PdfString);
|
||
}
|
||
else if (item.Type == PdfObject.NUMBER) {
|
||
if (-(item as PdfNumber).FloatValue * d > size) {
|
||
t[i++] = " ";
|
||
}
|
||
}
|
||
}
|
||
return String.Concat(t);
|
||
}
|
||
|
||
float GetFontSize(Matrix tm) {
|
||
float size = CurrentGraphicState.FontSize * tm[Matrix.I22];
|
||
if (size < 0) {
|
||
size = -size;
|
||
}
|
||
return size;
|
||
}
|
||
|
||
Matrix GetTextMatrix() {
|
||
return RotationMatrix != null
|
||
? RotationMatrix.Multiply(TextMatrix).Multiply(CurrentGraphicState.TransMatrix)
|
||
: TextMatrix.Multiply(CurrentGraphicState.TransMatrix);
|
||
}
|
||
|
||
static Bound CreateBoundFromMatrix(Matrix tm, float textWidth, float size) {
|
||
var l = tm[Matrix.I31];
|
||
var b = tm[Matrix.I32];
|
||
var r = tm[Matrix.I31] + textWidth * tm[Matrix.I11];
|
||
var t = tm[Matrix.I32] + size;
|
||
float x;
|
||
if (l > r) {
|
||
x = r; r = l; l = x;
|
||
}
|
||
if (b > t) {
|
||
x = t; t = b; b = x;
|
||
}
|
||
return new Bound(l, b, r, t);
|
||
}
|
||
|
||
/// <summary>
|
||
/// 检查 <paramref name="b"/> 是否处于 <paramref name="a"/> 之内。
|
||
/// </summary>
|
||
/// <param name="a">大边框。</param>
|
||
/// <param name="b">小边框。</param>
|
||
/// <returns>小边框完全处于大边框内，则返回 true。</returns>
|
||
internal static bool IsBoundOutOfRectangle(Rectangle a, Bound b) {
|
||
return b.Right < a.Left
|
||
|| b.Top < a.Bottom
|
||
|| b.Bottom > a.Top
|
||
|| b.Left > a.Right;
|
||
}
|
||
|
||
}
|
||
|
||
sealed class LevelProcessor
|
||
{
|
||
readonly AutoBookmarkFilter[] _filters;
|
||
readonly AutoBookmarkOptions.LevelAdjustmentOption[] _options;
|
||
|
||
internal LevelProcessor(IList<AutoBookmarkOptions.LevelAdjustmentOption> options) {
|
||
var l = options.Count;
|
||
_filters = new AutoBookmarkFilter[l];
|
||
_options = new AutoBookmarkOptions.LevelAdjustmentOption[l];
|
||
for (int i = 0; i < l; i++) {
|
||
_filters[i] = options[i].Condition.CreateFilter();
|
||
_options[i] = options[i];
|
||
}
|
||
}
|
||
|
||
internal float ChangeSizeLevel(AutoBookmarkContext context) {
|
||
for (int i = 0; i < _options.Length; i++) {
|
||
var o = _options[i];
|
||
if (o.FilterBeforeMergeTitle && context.IsTextMerged) {
|
||
continue;
|
||
}
|
||
if (_filters[i].Matches(context)) {
|
||
return o.RelativeAdjustment ? o.AdjustmentLevel + context.TextInfo.Size : o.AdjustmentLevel;
|
||
}
|
||
}
|
||
return context.TextInfo.Size;
|
||
}
|
||
}
|
||
}
|
||
}
|