Preprocessing of multi-line rotated electronic ink
View Patent ↗An electronic ink object is preprocessed for improving handwriting recognition results. An electronic ink object, possibly having multiple lines of non-horizontal ink, is preprocessed by segmenting or separating the electronic ink object into one or more lines, computing a writing angle of each line, and rotating each line so that it is horizontal.
1. A method of preprocessing an electronic ink object comprising the steps of:
(a) segmenting the electronic ink object comprising at least one ink stroke into at least one line by performing the steps of:
(i) identifying a plurality of features for each ink stroke of the electronic ink object; and
(ii) classifying each ink stroke as part of a new line, a current line, or a previous line;
(b) estimating a writing angle of each line;
(c) rotating each line to make horizontal a centerline of the line; and
wherein if the ink stroke is part of the current line, the step of estimating includes the step of re-computing a slope of the current line.
2. A method of preprocessing an electronic ink object comprising the steps of:
(a) segmenting the electronic ink object comprising at least one ink stroke into at least one line by performing the steps of:
(i) identifying a plurality of features for each ink stroke of the electronic ink object; and
(ii) classifying each ink stroke as part of a new line,current line; or a previous line
(b) estimating a writing angle of each line;
(c) rotating each line to make horizontal a centerline of the line; and
wherein if the ink stroke is part of the current line, the step of estimating includes the step of re-computing a slope of a centerline of the current line using a Least Mean Squares algorithm.
3. A method of preprocessing an electronic ink object comprising the steps of:
(a) segmenting the electronic ink object comprising at least one ink stroke into at least one line by performing the steps of:
(i) identifying a plurality of features for each ink stroke of the electronic ink object; and
(ii) classifying each ink stroke as part of a new line, a current line; or a previous line
(b) estimating a writing angle of each line;
(c) rotating each line to make horizontal a centerline of the line; and
wherein if the ink stroke is part of the previous line, the step of estimating includes the step of re-computing a slope of the previous line.
4. A method of preprocessing an electronic ink object comprising the steps of:
(a) segmenting the electronic ink object comprising at least one ink stoke into at least one line by performing the steps of:
(i) identifying a plurality of features for each ink stroke of the electronic ink object; and
(ii) classifying each ink stroke as part of a new line, a current line, or a previous line
(b) estimating a writing angle of each line;
(c) rotating each line to make horizontal a centerline of the line; and
wherein if the ink stroke is part of the previous line, the step of estimating includes the step of re-computing a slope of a centerline of the previous line using a Least Mean Squares algorithm.