What is OCR (Optical Character Recognition)?

Written by Cláudia Gómez | 07/26/23

Optical character recognition (OCR) is a tool that uses artificial intelligence algorithms and models to convert images of printed or handwritten text into editable text.

The OCR process involves the detection and extraction of individual characters from an image and their subsequent conversion into digital text.

 

How does OCR software work?

OCR software follows a series of steps to perform character recognition on an image. First, image acquisition is performed using a scanner or digital camera. The image is then processed to remove noise and improve visual quality. This involves preprocessing techniques such as distortion correction, shadow or blemish removal and contrast enhancement.

Once the image has been preprocessed, text segmentation is performed. This involves identifying the regions of the image containing text and separating the individual characters within those regions. Segmentation can be challenging due to variability in size, font and character arrangement.

Once segmented, the individual characters are subjected to a recognition process. At this stage, classification algorithms that use previously trained machine learning or deep learning models are employed. These models analyze the visual features of the characters and compare them with known patterns to assign them a corresponding label.

 

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What is an OCR system used for?

OCR systems have diverse applications in multiple fields. In the business environment, for example, they are used for the digitization of documents, allowing the conversion of paper documents into electronic files that can be stored, searched and processed efficiently. OCR is essential for automating administrative processes, such as extracting data from invoices or forms, streamlining repetitive tasks and minimizing human error.

In the field of accessibility, OCR plays a crucial role in converting printed text into accessible formats for the visually impaired. Text images are converted into digital text, which can be read by screen readers or converted into braille.

 

The benefits of an optical character recognition system

There are many benefits to implementing an OCR system. Firstly, it improves efficiency by eliminating the need to perform manual data entry tasks. This saves valuable time and resources. In addition, OCR reduces human errors associated with manual transcription, resulting in more accurate data once extracted.

Another key benefit is the ability to search for and retrieve information. By converting paper documents into digital text, conducting quick searches is enabled, making it easier to locate and retrieve relevant information in large volumes of documents.

 

 

How AI is trained to recognize a digital image

Training models for digital image recognition is a fundamental process in the development of artificial intelligence systems. To achieve this, a significant amount of labeled image data is required. These datasets are used to feed the model during training and allow it to learn to recognize patterns and features in the images.

During training, machine learning algorithms, such as convolutional neural networks (CNNs) are used, which are particularly efficient in processing image data. These networks are composed of multiple layers of neurons, designed to extract and process specific features from images.

The training process involves adjusting the weights and internal connections of the model to minimize the difference between the predictions it makes and the actual image labels. This is achieved through the use of optimization techniques, such as gradient descent, which gradually adjust the weights to improve model accuracy.

It is important to divide the data into training and validation sets. The training set is used for the adjustment of the model weights, while the validation set is used to evaluate its performance and avoid overfitting. Overfitting occurs when the model becomes too specific and does not generalize well to new images.

During the training process, the training set is used multiple times, adjusting the weights and evaluating the performance of the model on the validation set. This allows adjustments to be made to the model architecture, using hyperparameters and regularization techniques to improve its recognition capability.

Training image recognition models requires significant computational power, as the models typically have millions of parameters and multiple passes through the data are needed to achieve optimal performance. In addition, the training process can take time, depending on the size of the dataset and the complexity of the model.

In summary, model training for image recognition involves feeding the model with labeled image data, adjusting the internal weights and connections through machine learning algorithms, and validating and tuning the model to improve its recognition capability. It is an iterative process that requires a significant amount of data and computational resources.

 

 

Image recognition with deep learning and machine learning

Deep learning, a branch of machine learning, has revolutionized image recognition and OCR. Deep neural networks, known as convolutional neural networks (CNNs), have been shown to be especially effective in recognizing characters in images.

CNNs are capable of learning hierarchical representations of visual features through multiple layers of processing. This allows them to capture the complex and subtle details of characters, which significantly improves OCR accuracy.

In addition to CNNs, more traditional machine learning approaches are also used, such as classifiers based on manually extracted features. These classifiers use image processing techniques, like edge extraction or Hough transform, to identify characteristic patterns in images.

 

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How Pangeanic can help you to implement an OCR system

Although Pangeanic is not an OCR specialist and does not offer a customizable service by default, we can help you implement an OCR system. To do this, the first thing would be to assess your specific needs and objectives for the OCR system, understanding what type of documents you want to process, the accuracy and speed required, as well as any additional features needed.

We could then research specialized OCR vendors and select those that best fit your requirements and budget. Once the right provider has been identified, we would take care of integrating their services into your existing infrastructure, working together to establish the necessary connections and ensuring a seamless integration.

Although Pangeanic's service is not customizable, we can explore the option of customizing the results obtained from the OCR system by developing additional scripts or tools to adapt the extracted data to your specific needs.

In addition, we would provide ongoing support and maintenance services to ensure the proper functioning of the system over the long run, including software upgrades, technical troubleshooting and performance monitoring.