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Pdf2Parquet Transform

The Pdf2Parquet transform iterates through PDF, Docx, Pptx, Images files or zip of files and generates parquet files containing the converted document in Markdown or JSON format.

The conversion is using the Docling package.

Please see the set of transform project conventions for details on general project conventions, transform configuration, testing and IDE set up.

Contributors

  • Michele Dolfi (dol@zurich.ibm.com)

Input files

This transform supports the following input formats:

  • PDF documents
  • DOCX documents
  • PPTX presentations
  • Image files (png, jpeg, etc)
  • HTML pages
  • Markdown documents
  • ASCII Docs documents

The input documents can be provided in a folder structure, or as a zip archive. Please see the configuration section for specifying the input files.

Output format

The output table will contain following columns

output column name data type description
source_filename string the basename of the source archive or file
filename string the basename of the PDF file
contents string the content of the PDF
document_id string the document id, a random uuid4
document_hash string the document hash of the input content
ext string the detected file extension
hash string the hash of the contents column
size string the size of contents
date_acquired date the date when the transform was executing
num_pages number number of pages in the PDF
num_tables number number of tables in the PDF
num_doc_elements number number of document elements in the PDF
pdf_convert_time float time taken to convert the document in seconds

Configuration

The transform can be initialized with the following parameters.

Parameter Default Description
data_files_to_use - The files extensions to be considered when running the transform. Example value ['.pdf','.docx','.pptx','.zip']. For all the supported input formats, see the section above.
batch_size -1 Number of documents to be saved in the same result table. A value of -1 will generate one result file for each input file.
artifacts_path Path where to Docling models artifacts are located, if unset they will be downloaded and fetched from the HF_HUB_CACHE folder.
contents_type text/markdown The output type for the contents column. Valid types are text/markdown, text/plain and application/json.
do_table_structure True If true, detected tables will be processed with the table structure model.
do_ocr True If true, optical character recognition (OCR) will be used to read the content of bitmap parts of the document.
ocr_engine easyocr The OCR engine to use. Valid values are easyocr, tesseract, tesseract_cli.
bitmap_area_threshold 0.05 Threshold for running OCR on bitmap figures embedded in document. The threshold is computed as the fraction of the area covered by the bitmap, compared to the whole page area.
pdf_backend dlparse_v2 The PDF backend to use. Valid values are dlparse_v2, dlparse_v1, pypdfium2.
double_precision 8 If set, all floating points (e.g. bounding boxes) are rounded to this precision. For tests it is advised to use 0.

Example

{
    "data_files_to_use": ast.literal_eval("['.pdf','.docx','.pptx','.zip']"),
    "contents_type": "application/json",
    "do_ocr": True,
}

Usage

Launched Command Line Options

When invoking the CLI, the parameters must be set as --pdf2parquet_<name>, e.g., --pdf2parquet_do_ocr=true.

Running the samples

To run the samples, use the following make target

  • run-cli-sample - runs dpk_pdf2parquet/transform_python.py using command line args

These targets will activate the virtual environment and set up any configuration needed. Use the -n option of make to see the detail of what is done to run the sample.

For example, 

make run-cli-sample
...
Then 
ls output
To see results of the transform.

Code example

See the sample notebook for an example

Transforming data using the transform image

To use the transform image to transform your data, please refer to the running images quickstart, substituting the name of this transform image and runtime as appropriate.

Testing

Following the testing strategy of data-processing-lib

Currently we have: - Unit test - Integration test

Pdf2parquet Ray Transform

This module implements the ray version of the pdf2parquet transform.

Configuration and command line Options

Ingest PDF to Parquet configuration and command line options are the same as for the base python transform.

Running

Launched Command Line Options

When running the transform with the Ray launcher (i.e., TransformLauncher), in addition to those available to the transform for the Python version in this file, the set of launcher options are available.

Transforming data using the transform image

To use the transform image to transform your data, please refer to the running images quickstart, substituting the name of this transform image and runtime as appropriate.

Prometheus metrics

The transform will produce the following statsd metrics:

metric name Description
worker_pdf_doc_count Number of PDF documents converted by the worker
worker_pdf_pages_count Number of PDF pages converted by the worker
worker_pdf_page_avg_convert_time Average time for converting a single PDF page on each worker
worker_pdf_convert_time Time spent converting a single document

Credits

The PDF document conversion is developed by the AI for Knowledge group in IBM Research Zurich. The main package is Docling.