{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

recognition - Symbol Recognition in SketchBased Interfaces...

Info icon This preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Symbol Recognition in Sketch- Based Interfaces Lecture #10: Symbol Recognition Fall 2009 CAP 6105 – Pen-Based User Interfaces ©Joseph J. LaViola Jr. Joseph J. LaViola Jr. Fall 2009 Recall Pen-Based Interface Dataflow Raw Stroke Preprocessing Segmentation Data Feature Extraction And Analysis Classification Ink Parsing Sketch Understanding Fall 2009 CAP 6105 – Pen-Based User Interfaces ©Joseph J. LaViola Jr. Make Inferences
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2 Symbol Recognition Want to recognize handwritten symbols h t characters shapes gestures Use machine learning approach Which algorithm? Fall 2009 CAP 6105 – Pen-Based User Interfaces ©Joseph J. LaViola Jr. depends on number of symbols in alphabet complexity (i.e., similarity of symbols) distribution assumptions Recognition Algorithms Many different approaches Machine learning techniques (classification) linear classifiers k-means classifiers neural networks Hidden Markov Models template matching support vector machines AdaBoost Fall 2009 CAP 6105 – Pen-Based User Interfaces ©Joseph J. LaViola Jr. Curve matching elastic matching Primitive decomposition
Image of page 2
3 Rubine’s Gesture Recognition Algorithm (Rubine 1991) Simple linear classifier Utilizes rejection metrics Assumes normality for features Simple to implement Does not need a lot of training samples Fall 2009 CAP 6105 – Pen-Based User Interfaces ©Joseph J. LaViola Jr. Recall Rubine’s Feature Set Cosine and sine of initial angle Length and angle of bounding box diagonal Distance between first and last point Cosine and sine of angle between first and last point Total gesture length Total angle traversed Sum of absolute value of the angle at each point Fall 2009 CAP 6105 –
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern