Invoice OCR API

This project is an OCR data extraction from Invoices or bills. This project utilizes TensorFlow, Pytesseract, Ollama, and Gemma_2b.

Identifiable parameters

Company Name, Company Address, Customer Name, Customer Address, Invoice Number, Invoice Date, Due Date, Description, Quantity, Unit Price, Taxes, Amount, Total

Working

This project mainly consists of three parts

1. Tensorflow Model: this model finds the ROI(region of interest) from the invoice Image. the ROI is given to Tesseract.
2. Tesseract: Pytessract extracts text from the image(ocr engine).
3. NLP: Gemma_2b is used with Ollama for NLP which corrects the text extracted by Tesseract

Note

• Tensorflow model is stored in models/saved_model folder

Installation

Note

• python3 -m venv venv to create python virtual env
• ./venv/scripts/activate to activate venv in Windows or source venv/bin/activate in Linux
• run pip install -r requirements.txt to install necessary packages
• Need to install Ollama as per Ollama documentation, for Linux curl -fsSL https://ollama.com/install.sh | sh
• run ollama run gemma2:2b to download NLP Gemma_2b model.
• run sudo apt install tesseract-ocr to install tesseract on Linux machines or for Windows, visit (tesseract for windows)[https://tesseract-ocr.github.io/tessdoc/Compiling.html#windows]
• To run the program python app.py

API Request Model

Sample API Request Model(POST)

• headers:

Content-Type : application/json

• body:

    {
    "image": "{image in base64 Format}"

    } 

API Response Model

Sample API Response:

{
    "Company Name": "TEMPUSTIC CONSULTORIA TECNOLOGICA SL",
    "Company Address": "C/ PIE DE ALTAR N° 7\n28229 VILLANUEVA DEL PARRDILLO\nMADRID",
    "Customer Name": "SM TECNOLOGIA, S.L.U.",
    "Customer Address": "Poligono Industrial Os Airios, Sector 2 - Parcela 4\n15320 As Pontes\nA Corufia",
    "Invoice Number": "2023.11",
    "Invoice Date": "31/05/2023",
    "Due Date": null,
    "Description": "Hora Programador Java Junior",
    "Quantity": 30,
    "Unit Price": 176.00,
    "Taxes": 1108.80,
    "Amount": 5280.00,
    "Total": 6388.80
}