do_ocr_multi_class_cnn🔗
Short description🔗
do_ocr_multi_class_cnn — Classify multiple characters with an CNN-based OCR classifier.
Signature🔗
do_ocr_multi_class_cnn( region Character, image Image, ocr_cnn OCRHandle, out string Class, out real Confidence )
Description🔗
do_ocr_multi_class_cnn computes the best class for each of
the characters given by the regions Character and the gray
values Image with the OCR classifier OCRHandle and
returns the classes in Class and the corresponding
confidences (probabilities) of the classes in Confidence.
In contrast to do_ocr_single_class_cnn,
do_ocr_multi_class_cnn can classify multiple characters in
one call, and therefore typically is faster than a loop that uses
do_ocr_single_class_cnn to classify single characters.
However, do_ocr_multi_class_cnn can only return the best
class of each character. Because the confidences can be interpreted as
probabilities, it is easier to check whether a character has been
classified with too much uncertainty. This is usually not a disadvantage,
except in cases where the classes overlap so much that in many cases the
second best class must be examined to be able to decide the class of the
character. In these cases, do_ocr_single_class_cnn should be used.
A string of the number
\('\backslash 032'\) (alternatively
displayed as \('\backslash 0x1A'\)) in
Class signifies that the region has been classified as rejection
class.
Execution information🔗
Execution information
-
Multithreading type: reentrant (runs in parallel with non-exclusive operators).
-
Multithreading scope: global (may be called from any thread).
-
Automatically parallelized on internal data level.
Parameters🔗
Character (input_object) region(-array) → object
Characters to be recognized.
Image (input_object) singlechannelimage → object (byte / uint2)
Gray values of the characters.
OCRHandle (input_control) ocr_cnn → (handle)
Handle of the OCR classifier.
Class (output_control) string(-array) → (string)
Result of classifying the characters with the CNN.
Number of elements: Class == Character
Confidence (output_control) real(-array) → (real)
Confidence of the class of the characters.
Number of elements: Confidence == Character
Result🔗
If the parameters are valid, the operator
do_ocr_multi_class_cnn returns the value 2 (H_MSG_TRUE). If
necessary, an exception is raised.
Combinations with other operators🔗
Combinations
Possible predecessors
Alternatives
Module🔗
OCR/OCV