Grok Bot
77 lines
3.0 KiB
Python
77 lines
3.0 KiB
Python
"""Read a PDF's text layer and image positions with poppler. No guessing: coordinates in, text out."""
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import os
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import re
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import subprocess
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import tempfile
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import xml.etree.ElementTree as ET
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def _run(cmd):
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return subprocess.run(cmd, check=True, capture_output=True, text=True).stdout
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def page_geometry(pdf):
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"""[(width, height)] per page as displayed (rotation applied)."""
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n = int(re.search(r"^Pages:\s+(\d+)", _run(["pdfinfo", pdf]), re.M).group(1))
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out = _run(["pdfinfo", "-f", "1", "-l", str(n), pdf])
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sizes = {int(m[0]): (float(m[1]), float(m[2])) for m in re.findall(r"^Page\s+(\d+) size:\s+([\d.]+) x ([\d.]+)", out, re.M)}
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rots = {int(m[0]): int(m[1]) for m in re.findall(r"^Page\s+(\d+) rot:\s+(\d+)", out, re.M)}
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geo = []
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for p in range(1, n + 1):
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w, h = sizes[p]
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if rots.get(p, 0) in (90, 270):
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w, h = h, w
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geo.append((w, h))
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return geo
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def halves(width, height):
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"""A landscape page that holds two book pages is read as two units, left then right."""
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if width > height * 1.2:
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return [("L", 0, width / 2), ("R", width / 2, width / 2)]
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return [(None, 0, width)]
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def chars_per_page(pdf):
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"""Number of non-space characters in the text layer of each page."""
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n = len(page_geometry(pdf))
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out = []
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for p in range(1, n + 1):
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txt = _run(["pdftotext", "-f", str(p), "-l", str(p), pdf, "-"])
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out.append(len(re.sub(r"\s", "", txt)))
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return out
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def units(pdf):
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"""Reading units in order: [{'pdf_page', 'half', 'text'}]. Text keeps the layout (indentation, hyphens)."""
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result = []
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for p, (w, h) in enumerate(page_geometry(pdf), start=1):
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for half, x, width in halves(w, h):
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text = _run(["pdftotext", "-layout", "-f", str(p), "-l", str(p),
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"-x", str(int(x)), "-y", "0", "-W", str(int(width)), "-H", str(int(h)), pdf, "-"])
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result.append({"pdf_page": p, "half": half, "text": text.replace("\f", "")})
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return result
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def images(pdf):
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"""Images with their page, half and pixel size: [{'pdf_page', 'half', 'width', 'height'}]."""
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geo = page_geometry(pdf)
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found = []
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with tempfile.TemporaryDirectory() as tmp:
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subprocess.run(["pdftohtml", "-xml", "-q", pdf, os.path.join(tmp, "o")], check=True, capture_output=True)
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root = ET.parse(os.path.join(tmp, "o.xml")).getroot()
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for page in root.iter("page"):
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p = int(page.get("number"))
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w, h = geo[p - 1]
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scale = float(page.get("width")) / w
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for img in page.iter("image"):
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cx = (float(img.get("left")) + float(img.get("width")) / 2) / scale
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half = None
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for name, x, width in halves(w, h):
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if x <= cx < x + width:
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half = name
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found.append({"pdf_page": p, "half": half,
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"width": round(float(img.get("width")) / scale),
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"height": round(float(img.get("height")) / scale)})
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return found
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