Highlight Texts for Debugging
using IronOcr;

IronTesseract ocrTesseract = new IronTesseract();

using var ocrInput = new OcrInput();
ocrInput.LoadPdf("document.pdf");
ocrInput.HighlightTextAndSaveAsImages(ocrTesseract, "highlight_page_", ResultHighlightType.Paragraph);
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Highlight Texts for Debugging

Highlight Texts for Debugging

IronOCR includes built-in support to visually highlight OCR-detected elements (characters, words, lines, or paragraphs) on images or pages, and export them as PNGs for debugging.

  • OCR-based region detection replaces manual rectangle definitions
  • HighlightTextAndSaveAsImages(ocr, prefix, highlightType) overlays red boxes around detected elements - paragraphs, lines, words, or characters - and saves each page as an image.
  • Uses ResultHighlightType to choose what to highlight: Character, Word, Line, or Paragraph.
  • Handles detection and drawing internally - much simpler than manually specifying rectangle coordinates.

Optional Manual Approach via StampCropRectangles

If you want to manually handle bounding boxes from OCR results:

  • result.Words (or .Lines, .Paragraphs) yields collections whose elements expose X/Y/Width/Height for each detected region.
  • StampCropRectanglesAndSaveAs(...) visualizes those rectangles and writes images to disk
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