public void GetBlocks(string name, string[] expected)
{
if (name == "90 180 270 rotated.pdf")
{
// The 'TimesNewRomanPSMT' font is used by this particular document. Thus, results cannot be trusted on
// platforms where this font isn't generally available (e.g. OSX, Linux, etc.), so we skip it!
var font = SystemFontFinder.Instance.GetTrueTypeFont("TimesNewRomanPSMT");
Skip.If(font == null, "Skipped because the font TimesNewRomanPSMT could not be found in the execution environment.");
}
var options = new DocstrumBoundingBoxes.DocstrumBoundingBoxesOptions()
{
LineSeparator = " "
};
using (var document = PdfDocument.Open(DlaHelper.GetDocumentPath(name)))
{
var page = document.GetPage(1);
var words = NearestNeighbourWordExtractor.Instance.GetWords(page.Letters);
var blocks = new DocstrumBoundingBoxes(options).GetBlocks(words);
Assert.Equal(expected.Length, blocks.Count);
var orderedBlocks = blocks.OrderBy(b => b.BoundingBox.BottomLeft.X)
.ThenByDescending(b => b.BoundingBox.BottomLeft.Y).ToList();
for (int i = 0; i < orderedBlocks.Count; i++)
{
Assert.Equal(expected[i], orderedBlocks[i].Text);
}
}
}
public void GetBlocksStatic(string name, string[] expected)
{
if (name == "90 180 270 rotated.pdf")
{
// The 'TimesNewRomanPSMT' font is used by this particular document. Thus, results cannot be trusted on
// platforms where this font isn't generally available (e.g. OSX, Linux, etc.), so we skip it!
var font = SystemFontFinder.Instance.GetTrueTypeFont("TimesNewRomanPSMT");
Skip.If(font == null, "Skipped because the font TimesNewRomanPSMT could not be found in the execution environment.");
}
var options = new DocstrumBoundingBoxes.DocstrumBoundingBoxesOptions()
{
LineSeparator = " "
};
using (var document = PdfDocument.Open(DlaHelper.GetDocumentPath(name)))
{
var page = document.GetPage(1);
var words = NearestNeighbourWordExtractor.Instance.GetWords(page.Letters).ToList();
// Docstrum using static methods
// Filter out white spaces
words = words.Where(w => !string.IsNullOrWhiteSpace(w.Text)).ToList();
var wlBounds = options.WithinLineBounds;
var wlBinSize = options.WithinLineBinSize;
var wlMultiplier = options.WithinLineMultiplier;
var blBounds = options.BetweenLineBounds;
var blBinSize = options.BetweenLineBinSize;
var blMultiplier = options.BetweenLineMultiplier;
var maxDegreeOfParallelism = options.MaxDegreeOfParallelism;
var angularDifferenceBounds = options.AngularDifferenceBounds;
var wordSeparator = options.WordSeparator;
var lineSeparator = options.LineSeparator;
var epsilon = options.Epsilon;
// 1. Estimate within line and between line spacing
if (!DocstrumBoundingBoxes.GetSpacingEstimation(words, wlBounds, wlBinSize, blBounds, blBinSize,
maxDegreeOfParallelism,
out double withinLineDistance, out double betweenLineDistance))
{
if (double.IsNaN(withinLineDistance))
{
withinLineDistance = 0;
}
if (double.IsNaN(betweenLineDistance))
{
betweenLineDistance = 0;
}
}
// 2. Determination of Text Lines
double maxWithinLineDistance = wlMultiplier * withinLineDistance;
var lines = DocstrumBoundingBoxes.GetLines(words, maxWithinLineDistance, wlBounds, wordSeparator, maxDegreeOfParallelism).ToArray();
// 3. Structural Block Determination
double maxBetweenLineDistance = blMultiplier * betweenLineDistance;
var blocks = DocstrumBoundingBoxes.GetStructuralBlocks(lines, maxBetweenLineDistance, angularDifferenceBounds, epsilon, lineSeparator, maxDegreeOfParallelism).ToList();
Assert.Equal(expected.Length, blocks.Count);
var orderedBlocks = blocks.OrderBy(b => b.BoundingBox.BottomLeft.X)
.ThenByDescending(b => b.BoundingBox.BottomLeft.Y).ToList();
for (int i = 0; i < orderedBlocks.Count; i++)
{
Assert.Equal(expected[i], orderedBlocks[i].Text);
}
}
}
//https://github.com/pdfminer/pdfminer.six/blob/f389b97923c7a847bc9c6f4c3374951e1a7ff764/pdfminer/layout.py#L593
/// <summary>
/// group_objects: group text object to textlines.
/// </summary>
/// <param name="laparams"></param>
/// <param name="objs"></param>
/// <returns></returns>
public IEnumerable <TextLine> group_objects(LAParams laparams, IEnumerable <Letter> objs)
{
Letter obj0 = null;
TextLine line = null;
foreach (var obj1 in objs)
{
if (obj0 != null)
{
// halign: obj0 and obj1 is horizontally aligned.
//
// +------+ - - -
// | obj0 | - - +------+ -
// | | | obj1 | | (line_overlap)
// +------+ - - | | -
// - - - +------+
//
// |<--->|
// (char_margin)
var halign = obj0.is_compatible(obj1) && obj0.is_voverlap(obj1) &&
Math.Min(obj0.GlyphRectangle.Height, obj1.GlyphRectangle.Height) * laparams.line_overlap < obj0.voverlap(obj1) &&
obj0.hdistance(obj1) < Math.Max(obj0.GlyphRectangle.Width, obj1.GlyphRectangle.Width) * laparams.char_margin;
var is_hoverlap = DocstrumBoundingBoxes.GetStructuralBlockingParameters(new PdfLine(obj0.StartBaseLine, obj0.EndBaseLine), new PdfLine(obj1.StartBaseLine, obj1.EndBaseLine), 1e-3,
out double angularDifference, out double normalisedOverlap, out double perpendicularDistance);
// valign: obj0 and obj1 is vertically aligned.
//
// +------+
// | obj0 |
// | |
// +------+ - - -
// | | | (char_margin)
// +------+ - -
// | obj1 |
// | |
// +------+
//
// |<-->|
// (line_overlap)
var valign = laparams.detect_vertical && obj0.is_compatible(obj1) && obj0.is_hoverlap(obj1) &&
Math.Min(obj0.GlyphRectangle.Width, obj1.GlyphRectangle.Width) * laparams.line_overlap < obj0.hoverlap(obj1) &&
obj0.vdistance(obj1) < Math.Max(obj0.GlyphRectangle.Height, obj1.GlyphRectangle.Height) * laparams.char_margin;
if ((halign && line.isHorizontal()) || (valign && line.isVertical()))
{
//line.Add(obj1);
throw new NotImplementedException();
}
else if (line != null)
{
yield return(line);
line = null;
}
else
{
if (valign && !halign)
{
throw new NotImplementedException();
}
else if (halign && !valign)
{
throw new NotImplementedException();
}
else
{
throw new NotImplementedException();
}
}
}
}
if (line == null)
{
//line = LTTextLineHorizontal(laparams.word_margin)
//line.add(obj0)
}
yield return(line);
}
