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📄 Pdf Extract QGIS Plugin

Pdf Extract is a QGIS plugin that extracts vector data and text from PDF files and converts them to multiple vector formats including DXF, Shapefile, and GeoJSON. It uses PyMuPDF (fitz) to read PDF content and ezdxf to generate DXF files. The plugin supports multi-page PDFs and offers options to extract geometry and text separately, making it suitable for converting PDF maps or drawings into editable GIS layers.

✨ Features​

  • Vector Conversion: Converts PDF vector graphics (lines, curves, polygons) into editable vector formats including DXF, Shapefile, and GeoJSON.
  • Crop Region Selection: Interactively select a rectangular region on the PDF preview to extract only the content within that area. Perfect for isolating specific sections of large drawings.
  • Geometry Filtering: Filter extracted geometries by minimum size or exclude curve types (Bezier/Splines) to clean up noisy data or focus on specific features.
  • Batch Processing: Select and convert multiple PDF files simultaneously. Each file is processed sequentially, and results are grouped for easy management.
  • Text Extraction: Extracts text from PDF files and converts them into DXF MTEXT entities or vector text layers in Shapefile/GeoJSON, preserving position and size.
  • Layer Separation: Automatically organizes output into distinct layers or files:
    • Geometry layers contain vector shapes (lines, curves, rectangles).
    • Text layers contain all text elements (labels and annotations).
  • Multi-page Support: Handles multi-page PDFs by generating separate files for each page and content type. For example:
    • output_p1_geom.dxf / .shp / .geojson for page 1 geometry
    • output_p1_text.dxf / .shp / .geojson for page 1 text
  • Output Formats: Supports exporting to DXF, Shapefile, and GeoJSON formats.
  • Automated Loading: Option to automatically load the generated output files into the current QGIS project.

⚙️ Installation​

Prerequisites​

The plugin relies on two Python libraries, which are automatically installed by qpip:

  • pymupdf (fitz)
  • ezdxf

Installation Steps​

  1. Install PdfExtract Plugin:

    • Download the plugin zip file (PdfExtract.zip).
    • Go to Plugins > Manage and Install Plugins....
    • Select Install from Zip.
    • Browse to the PdfExtract.zip file and click Install Plugin.
    • Note: If qpip is not installed, QGIS will prompt you to install it automatically. Click Yes to install qpip.

  2. Install Dependencies (Automatic):

    • Restart QGIS completely.
    • Upon restart, the qpip plugin will automatically detect the requirements.txt file in the plugin directory.
    • It will download and install the required libraries (pymupdf, ezdxf).
    • If prompted, confirm the installation.

  3. Manual Installation (If Automatic Installation Fails):

    If qpip does not prompt you or installation fails, you can install the dependencies manually using the OS Command Shell or QGIS Python Console.

    Method A: OS Command Shell (Recommended) Open the OSGeo4W Shell (Windows) or Terminal (macOS/Linux) and run: Common Path: C:\Program Files\QGIS 3.xx\OSGeo4W.bat

    pip install pymupdf ezdxf

    Note: Ensure you are using the python environment associated with your QGIS installation.

    Method B: QGIS Python Console

    1. Open QGIS.

    2. Go to Plugins > Python Console (or press Ctrl+Alt+P).

    3. Copy and run the following command to install pymupdf:

      import pip
      pip.main(['install', 'pymupdf'])

    4. Then run this command to install ezdxf:

      import pip
      pip.main(['install', 'ezdxf'])

    5. Restart QGIS after installation.

  4. Verify Installation:

    • Once QGIS is open, the plugin should be ready to use.

🧭 Usage Guide​

💬 Using the Dialog Interface​

  1. Open the Pdf Extract dialog from the QGIS main window via toolbar or menu.

  2. In the Input tab:

    • Click Browse... to open the file selection dialog (titled "Select PDF(s)").
    • Select one or more PDF files. You can hold Ctrl or Shift to select multiple files at once.
    • Selected files will be listed in the input field separated by semicolons (;).
    • Click Browse... to select the output folder.
    • Select the output format from the dropdown: Shapefile (.shp), GeoJSON (.geojson), or DXF (.dxf).
    • Optionally, check Load results into QGIS to load outputs automatically.

  3. Configure extraction options:

    • Crop Region (Optional): Click "Set Crop Region..." to interactively select a specific area:
      • A preview dialog opens showing the first page of the PDF.
      • Click and drag with the crosshair cursor to draw a rectangular selection.
      • Click "OK" to confirm or "Clear Selection" to reset.
      • The crop region applies to all pages being processed.
      • Only geometry and text fully contained within the crop region will be extracted.
      • Status label shows crop coordinates or "Full Page" if no crop is set.
    • Page Range: Navigate to the Advanced tab:
      • Choose to process All pages or specify a Page Range by entering the start and end page numbers. Selecting a page range allows you to convert only specific pages from the PDF.
    • Content Selection: Select what to extract:
      • Geometry: Extracts vector shapes such as lines, curves, and rectangles from the PDF.
      • Text: Extracts text elements including labels and annotations.
      • Both: Extracts both geometry and text for comprehensive conversion.
    • Filter Geometries:
      • Skip Curved Geometries: Check this option to exclude Bezier curves and splines from the extraction. Useful for simplifying output or removing decorative elements.
      • Minimum Size: Set a threshold (in points) to exclude small geometries such as dots, noise, or minor details. Geometries with a bounding box dimension smaller than this value will be skipped.

  4. Click Convert ▶️ to start processing.

    • The progress bar displays the status of the batch operation.
    • A confirmation message appears upon completion showing how many layers were loaded across all files.
    • If multiple files were processed, loaded layers are grouped under a "PDF_Batch_Import" group in the Layers panel.

📐 Crop Region Tips​

  • Isolate Sections: Use crop region to extract only a specific area of interest, such as a detail from a large plan drawing.
  • Remove Borders: Crop out title blocks, legends, or page borders by selecting only the main drawing area.
  • Multi-page Consistency: The selected crop region from the first page preview is applied to all pages in the batch.
  • Containment Filter: Only objects completely inside the crop region are extracted. Objects that extend beyond the boundary are excluded.

⚙️ Running the Algorithm Directly​

  1. Open the QGIS Processing Toolbox.

  2. Search for Pdf Extract.

  3. Configure the algorithm parameters:

    • Input PDF file path.
    • Output format (Shapefile or GeoJSON or DXF).
    • Output base path.
    • Option to load output into the project.
    • Skip Curved Geometries: Boolean flag to skip curves.
    • Minimum Size: Double value to set minimum geometry size threshold.

  4. Run the algorithm to process the PDF and generate vector output layers.

🐞 Troubleshooting​

"Missing dependencies" Error

If you see an error about missing pymupdf or ezdxf, ensure that the qpip plugin is installed and active. Restart QGIS to allow qpip to detect and install the missing packages.

Text not appearing​

  • Ensure the PDF actually contains text objects and not just images of text. You can verify this by trying to select text in a PDF viewer.
  • Check the PDF_TEXT layer or equivalent text layer in QGIS or your CAD software.

Distorted Geometry or Missing Features​

  • The converter supports standard PDF vector commands. Complex clipping paths, transparency groups, or unusual drawing commands might be simplified or ignored.
  • DXF output depends on ezdxf and its support capabilities.

Output Files Not Found or Not Loading​

  • Check the output folder path and file naming.
  • Confirm that the supported output formats are DXF, Shapefile, and GeoJSON.
  • Ensure output layers are loaded if the "Load results into QGIS" option is enabled.

🕵️‍♂️ Technical Details​

  • Coordinate System: PDF coordinates have their origin at the top-left with Y axis increasing downward. The plugin transforms these to GIS-compatible coordinates by flipping the Y axis to origin at bottom-left.
  • Units: The conversion preserves PDF point units (1/72 inch). Scale adjustments may be needed in QGIS based on your project's Coordinate Reference System (CRS).
  • Output File Naming: For multi-page PDFs, separate output files are created per page and content type with names like:
    • output_p1_geom.dxf / .shp / .geojson — Geometry layer for page 1
    • output_p1_text.dxf / .shp / .geojson — Text layer for page 1
  • Layer Separation: The plugin creates separate layers for geometry (lines, curves, rectangles) and text (labels, annotations) to aid editing and styling in GIS software.
  • Supported Output Formats: DXF (via ezdxf), Shapefile, and GeoJSON are supported as export formats.