Your personal data shared with us through this form will only be used for the intended purpose. The data will be protected and will not be shared with any third party.
OCR requires data annotation to be done to meet the requirement of designing and improving OCR systems. OCR is termed as optical character recognition which employs ML and Computer vision to translate image, scanned documents or handwritten text to machine readable text. Good annotation of data is critical when training neural networks in OCR so that the models can effectively identify and extricate information from such sources. Here's how data annotation helps in building and enhancing OCR systems:
1. Text Localization
Bounding Box Annotation for Text Regions : The first process in OCR is to identify is where text is located within an image or document. By labeling the text regions using bounding box, OCR systems are easily able to recognize areas containing texts. This assists the model in picking relevant parts and leaving out other parts such as images or graphics parts and white spaces.
Text Line and Word Segmentation : From the annotated image, one can segment the text to individual lines or words for better meaning structure of the image by the model. This is very helpful on thick documents, receipts or any form where characters might be closely grouped or of unequal interval.
2. Character-Level Annotation
Character Labeling : Every symbol within the text should be characterized independently if we are going to training OCR models based on handwriting or cursive script. Small-level annotations allow the model to distinguish between different letters numbers or the symbols, which assist the model to read written text better especially in situations where the text might be obscured or has some level of distortion.
Font and Style Annotation : Adding tags to characters with font attributes such as type (serif/sans-serif), and style (bold/italic) enhances the understanding by OCR systems of formatting, crucial when working with documents organized as legal contracts, research papers, or books.
3. Word Recognition
Word-Level Annotation : This is done by providing labels on every word in an image hence improving on the chances of the OCR system to read whole words rather than individual characters. This is especially important where context helps in decoding in that area especially in differentiating between characters such as “1”, “l”, or “O”, “0”.
Contextual Word Annotation : If words are annotated according to the context in which they are written – titles, headers, body text – then the OCR systems can get a better idea of how all the different parts of ‘text’ fit together as well as the function of the words within the document in question. This might be too important for enhancing the analysis of text layout and gaining knowledge of the structure of documents.
4. Language-Specific Annotation
Multilingual Text Annotation : The idea is that for OCR systems to work across multiple languages it is necessary to annotate text with language specific tags. This facilitates the model to appropriately tender between closely related languages that use different alphanumeric set (Latin, Cyrillic, Arabic, Chinese etc.). It also enables the system to translate between the languages in the documents that comprise more than one language.
Script-Specific Annotation : Transcribing the text based on particular script (Devanagari, Hangul or Greek, etc.) help to deal with multiple written languages by the OCR system. This is especially relevant for initiatives that require the usage of a single, interoperation system, like passports’ scan, legal documentation, and text in multiple languages.
5. Noise and Distortion Handling
Low-Resolution Text Annotation : Using text from images of low quality (e.g., captured from video surveillance cameras or scanned documents) to teach OCR models additionally includes recognizing low-quality text. If the characters are distorted caused by blur or pixelization of the image, the system learns how to label it correctly.
Noisy Background Annotation : Pictures or any type of papers may have noise in the form of ink marks, blurred texts or overlapping of a message. It also helps the OCR model to distinguish texts from the noise as well as from the texts in a complex background. This is important in OCR for documents that have faded over time in document archival or for receipts where the receipt background is busy with many designs.
6. Handwritten Text Annotation
Character and Word-Level Handwriting Annotation : Closely labeling characters, words on the handwriting also improves the OCR models specifically designed for handwriting. Text written by hand can be narrower, wider, of uneven spacing or of different style and angle; character level avoids such problems by providing immediate annotations for the neuromorphic model to learn from.
Cursive Text Annotation : As with decisions on letter configurations, annotations as to how the letters connect give models insight into the overall structure of cursive text. This is very handy while reading hand written letters, legal papers, documents or historical manuscripts.
7. Structure and Layout of documents.
Page Layout Annotation : Heads, foots, paragraphs, columns and etc. with the help of annotation are used to maintain the structure of the layout of the Document by OCR system. This is especially crucial in the digitization of all complicated documents for instance newspapers, forms and multi-column report.
Table and Chart Annotation : OCR systems sometimes meet tables or charts in the documents which they are scanning. Adding structural information to these elements allows for rows, columns, cells or other graphical content to be correctly identified and exploited for structured data extraction.
8. Special Character and Symbol Stamping
Non-Alphanumeric Character Annotation : Special marks, including but not limited to mathematical symbols like ∑, π, ÷, the currency symbols like $, €, ¥, and character punctuation like ‘,’ etc. creates a distinction that makes the OCR systems perceive non-forms of letters. This is important for financial, educational and technical writing as these denote certain symbols.
Logo and Stamp Annotation : On documents such as stamps or logos/ watermarks describing the location of such raster graphics enables the OCR system to differentiate between text and image. This brings the advantage of conserving the genuineness of records and stamping being mistaken as text.
9. Image and Graphic Embedding
Embedded Image Annotation : In documents there are frequently inserted images, graphs, or icons. A desirable property for the appearance of these regions is achieved by annotating the extent that OCR system does not attempt to texturize non-patterned areas. This is especially true on mixed media documents, the brochures, and reports obtained by scanning.
Text Overlay on Images : When it is necessary to search through images with text – icons, signs, product labels, stickers – the text annotation lets the model differentiate objects and find a text in overlays. This is very important especially for purposes of LPR, packaging features’ identification as well as the interpretation of signs.
10. Text Orientation and Skew
Rotated and Skewed Text Annotation : It indicates text occurrence at various angles in images or scanning the document inappropriately or capturing its photograph at an improper angle. Rotated or skewed text annotations enable the OCR system to identify and rectify text so that mere extraction can occur.
Vertical and Non-Linear Text Annotation : Many fonts are vertically oriented (Asian languages or stylized headings) or nonlinear (curved or circular text in logos); annotating them tells the model how to interpret these orientations.
11. Document Types and Formats
Structured vs. Unstructured Documents : Scenarios include annotating augmentation of various document types like invoices, legal contracts, handwritten notes, business cards enable the OCR systems to address both structured document and unstructured document type inputs differing in a specific pattern of layouts from that of free form text inputs. This enhance the performance of OCR across various application.
Form Field Annotation : Documents such as tax forms, questionnaires, etc., where form fields are present, it assists the OCR systems by writing labels of expected data on form fields.
12. These categories include Quality Control and Benchmarking in relation to cost control.
Correct vs. Incorrect Annotation : Getting a pass or a failure rate to the text indicates the effectiveness of OCR models and allows comparing the results. This annotated data is crucial for the further cycles of improvements, while the high error rate may be minimized by the experienced developers.
Ground Truth Annotation : This paper uses the human-created transcription of the textual descriptions of images (ground truth) to compare with descriptions generated by the OCR model. This aids in measuring the efficiency of OCR and is employed in training and validation phases to enhance the performance of a model.
Conclusion
A significance of the data annotation process is to enable AI models to parse, identify and extract text from various sources in OCR systems. When text is annotated at such granularities as character and word level as well as at layout and structure levels, OCR models can support many applications, including but not limited to digitization, preservation of documents and real-time OCR for dynamic environments.
Any Questions? Contact / Call / Email Us Right Away!
Get in touch
