How is OCR accuracy calculated?

Measuring OCR accuracy is done by taking the output of an OCR run for an image and comparing it to the original version of the same text. You can then either count how many characters were detected correctly (character level accuracy), or count how many words were recognized correctly (word level accuracy).

How do I increase my accuracy in OCR?

5 Ways to Improve OCR Accuracy

1. Good Quality of Source Images. Before using OCR, make sure you can read the images with your own eyes.
2. Right Size of Images.
3. Remove Noise / Denoise.
4. Increase Image Contrast.
5. De-skew Original Source.

What are the factors that affect the accuracy of OCR?

What are the factors that affect the accuracy of OCR?

• The Quality of the Original Document. Receipts often are priting on thermal paper by a low qualtiy printer.
• The Quality of the Scan. Scanners make a digital representation of visual input.
• The OCR Engine.
• Auto-matching.

How do you find the accuracy of the Tesseract OCR?

13 Answers

1. fix DPI (if needed) 300 DPI is minimum.
2. fix text size (e.g. 12 pt should be ok)
3. try to fix text lines (deskew and dewarp text)
4. try to fix illumination of image (e.g. no dark part of image)
5. binarize and de-noise image.

What is Python Tesseract?

Python-tesseract is an optical character recognition (OCR) tool for python. It is also useful as a stand-alone invocation script to tesseract, as it can read all image types supported by the Pillow and Leptonica imaging libraries, including jpeg, png, gif, bmp, tiff, and others.

Why is OCR difficult?

Lack of Scalability. Due to the issues present, OCR requires large amounts of both technical and human resources. OCR will often require huge volumes of memory and processing speed. This slows down the system and makes it more difficult to scan large volumes of documents.

How do I get Adobe Acrobat to recognize text?

Open a PDF file containing a scanned image in Acrobat for Mac or PC. Click on the “Edit PDF” tool in the right pane. Acrobat automatically applies optical character recognition (OCR) to your document and converts it to a fully editable copy of your PDF. Click the text element you wish to edit and start typing.

Can Tesseract read PDF?

Tesseract is an excellent open-source engine for OCR. But it can’t read PDFs on its own. Convert the PDF into images; Use OCR to extract text from those images.