ocrText

Object for storing OCR results

Description

ocrText object contains recognized text and metadata collected during optical character recognition (OCR). You can access the information contained in the object with the ocrText properties. You can also locate text that matches a specific pattern with the locateText function.

Creation

Create an ocrText object using the ocr function.

Properties

Text — Text recognized by OCR

array of characters

Text recognized by OCR, specified as an array of characters. The text includes white space and new line characters.

CharacterBoundingBoxes — Bounding box locations

M-by-4 matrix

Bounding box locations, stored as an M-by-4 matrix. Each row of the matrix contains a four-element vector, [x y width height]. The [x y] elements correspond to the upper-left corner of the bounding box. The [width height] elements correspond to the size of the rectangular region in pixels. The bounding boxes enclose text found in an image using the ocr function. Bounding boxes width and height that correspond to new line characters are set to zero. Character modifiers found in languages, such as Hindi, Tamil, and Bangalese, are also contained in a zero width and height bounding box.

CharacterConfidences — Character recognition confidence

array

Character recognition confidence, specified as an array. The confidence values are in the range [0, 1]. A confidence value, set by the ocr function, should be interpreted as a probability. The ocr function sets confidence values for spaces between words and sets new line characters to NaN. Spaces and new line characters are not explicitly recognized during OCR. You can use the confidence values to identify the location of misclassified text within the image by eliminating characters with low confidence.

Words — Recognized words

cell array

Recognized words, specified as a cell array.

WordBoundingBoxes — Bounding box location and size

M-by-4 matrix

Bounding box location and size, stored as an M-by-4 matrix. Each row of the matrix contains a four-element vector, [x y width height], that specifies the upper left corner and size of a rectangular region in pixels.

WordConfidences — Recognition confidence

array

Recognition confidence, specified as an array. The confidence values are in the range [0, 1]. A confidence value, set by the ocr function, should be interpreted as a probability. The ocr function sets confidence values for spaces between words and sets new line characters to NaN. Spaces and new line characters are not explicitly recognized during OCR. You can use the confidence values to identify the location of misclassified text within the image by eliminating words with low confidence.

Object Functions

locateText

Locate text pattern

Examples

Find and Highlight Text in an Image

businessCard = imread("businessCard.png");
ocrResults = ocr(businessCard);
bboxes = locateText(ocrResults,"MathWorks",IgnoreCase=true);
Iocr = insertShape(businessCard,"FilledRectangle",bboxes);
figure; imshow(Iocr);

Find Text Using Regular Expressions

     businessCard = imread('businessCard.png');
     ocrResults   = ocr(businessCard);
     bboxes = locateText(ocrResults, 'www.*com','UseRegexp', true);
     img    = insertShape(businessCard, 'FilledRectangle', bboxes);
     figure; imshow(img);

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

Usage notes and limitations:

• Use in a MATLAB Function block is not supported.

• The Words property cannot be accessed in code generation. Use the Text property in place of the Words property to access the OCR results.

Version History

Introduced in R2014a