How LiteParse's Grid Projection Algorithm Parses PDFs

PDFs store text in a manner that focuses on content placement rather than reading order, presenting challenges in text extraction due to their lack of structural organization. LiteParse addresses these challenges by utilizing a grid projection algorithm that projects text onto a monospace character grid, preserving alignment and structure without attempting to understand the layout as tables or columns. The algorithm works through several steps, including grouping text fragments into lines based on Y coordinates and extracting alignment anchors from recurring X positions. It classifies text items by their anchor type (left, right, center), ensuring that text is projected onto a grid while maintaining structural integrity. This approach is complemented by a debugging system that traces decision chains and allows for visual debugging, providing transparency and facilitating improvements. LiteParse's grid projection algorithm is open-source, offering users a tool for extracting spatially organized text from PDFs while maintaining the document's visual structure.