页面文本绝对坐标转相对定位：文本块分组构建行列布局解决方案问询

Hey there, let's break this down into actionable search queries and a practical approach to solve your problem.

These precise titles will help you find relevant algorithms and implementations in document layout processing:

• "How to group absolute-positioned text bounding boxes into layout islands for relative-flow document conversion (supports single/multi-column, paragraphs + figures)"
• "Algorithm to cluster text rectangles (absolute coordinates) into row/column layout islands for relative positioning in generic documents"
• "Document layout analysis: Convert absolute text bounding boxes to relative flow via island grouping"

Here's a step-by-step workflow to group your text rectangles into layout islands and build the relative flow structure:

1. Optional (but recommended): Normalize Coordinates
   Convert all absolute rectangle coordinates to a normalized scale relative to the page dimensions. This makes your logic consistent across different page sizes:

   # Example normalization in Python
   normalized_rects = []
   page_width, page_height = 800, 1200  # Replace with actual page size
   for rect in original_rects:
       norm_x = rect.x / page_width
       norm_y = rect.y / page_height
       norm_w = rect.width / page_width
       norm_h = rect.height / page_height
       normalized_rects.append((norm_x, norm_y, norm_w, norm_h))
   

2. Cluster into Row Candidates
   Sort all rectangles by their vertical center (or top y-coordinate), then group them into rows using a vertical proximity threshold. For example, if two rectangles' vertical centers are within 1/3 of the average text block height, they belong to the same row. This helps you capture horizontal lines of text or adjacent elements.

3. Split Rows into Layout Islands
   For each row candidate group, sort rectangles by their horizontal x-coordinate. Then split the row into islands by checking horizontal gaps: if the gap between two adjacent rectangles is significantly larger than typical intra-paragraph spacing (e.g., >50% of the average text block width), split them into separate islands. This handles multi-column layouts and separates paragraphs from side-by-side figures.

4. Merge Vertical Islands into Layout Blocks
   Associate islands that belong to the same vertical region. For example, if two islands (from consecutive rows) have overlapping horizontal ranges (overlap >70%) and their vertical gap is within twice the average line spacing, merge them into a single layout block. This builds complete paragraphs, figure captions, or multi-row elements.

5. Generate Relative Positioning
   For each finalized layout block, calculate its relative position (either relative to the page origin or the previous block). Then arrange the text blocks within each block in row-column order to form the relative text flow.

Key Notes #

• Use dynamic thresholds (calculated from your document's average text block size, line spacing) instead of fixed values for better adaptability to different document types.
• Since you don't need to handle overlapping rectangles, you can skip collision detection and focus solely on proximity-based clustering.
• For non-text elements (like figures), you can flag them early (via size or metadata) and treat them as separate islands to avoid mixing with text paragraphs.

内容的提问来源于stack exchange，提问作者Chpokeridze