find_text — Find text in an image.
find_text finds text specified by the TextModel in the Image and returns the result in TextResultID. Specific results of TextResultID can be obtained with get_text_result and get_text_object.
The text results in TextResultID differ, depending on how Mode was set when creating the TextModel with create_text_model_reader.
For a text model with Mode = 'auto' find_text extracts and classifies text of arbitrary size within the Image. It is possible to restrict the search to characters with specific attributes, see set_text_model_param for details.
For a text model with Mode = 'manual' reasonable parameters for the text model, including the expected character height and width, need to be set using set_text_model_param. Furthermore, the Image is preprocessed such that character like structures are enhanced. The resulting compensated image can be queried from TextResultID if 'persistence' was set to 'true' in TextModel.
Both the text models with Mode = 'auto' and Mode = 'manual' apply various thresholds to the input image and segment character candidates based on region and gray value features. These candidates are further clustered to lines. Each line is individually completed and tested if it fulfills the constraints of a text line. Text models with Mode set to 'auto' require a text line to consist of at least two characters, whereas text models with Mode set to 'manual' require a text line to consist of at least three characters. In a further step, punctuations and separators are added if the correspondent parameters were set via set_text_model_param. Finally, if TextModel contains 'text_line_structure' entries, the completed line is fitted to these structures.
find_text finds text which is roughly horizontally aligned in Image. text_line_orientation and rotate_image can be used to achieve this alignment.
Since memory is allocated for the text result during the call of find_text and during the following operations, the text result should be freed explicitly by the operator clear_text_result as soon as it is no longer used.
This operator returns a handle. Note that the state of an instance of this handle type may be changed by specific operators even though the handle is used as an input parameter by those operators.
Text model specifying the text to be segmented.
Result of the segmentation.
read_image (Image, 'numbers_scale') create_text_model_reader ('auto', 'Document_Rej.omc', TextModel) * Optionally specify text properties set_text_model_param (TextModel, 'min_char_height', 20) find_text (Image, TextModel, TextResultID) * Return character regions and corresponding classification results get_text_object (Characters, TextResultID, 'all_lines') get_text_result (TextResultID, 'class', Class) clear_text_result (TextResultID) clear_text_model (TextModel)
If the parameters are valid, the operator find_text returns the value 2 (H_MSG_TRUE). If necessary, an exception is raised.
create_text_model_reader, set_text_model_param, text_line_orientation, text_line_slant