Adaptive Screen Stabilization
- 1. Adaptive No-Shake Screen Reader Allen Xu, Marc Garneau Collegiate Institute April 7, 2018 York Region Science Fair
- 2. 2 • Stabilizing shaking mobile screens • Makes reading on mobile screen less stressful • Especially useful in unstable reading environments Objective
- 3. 3 Accelerometer • Measuring forces applied to the device • Measuring acceleration applied to the device • Includes gravity • Ad = -g - ∑F / mass • SI unit is m/s^2 • Supported by all devices
- 4. 4 Linear Acceleration • Measuring forces applied to the device • Measuring acceleration applied to the device • Not including gravity • Ad = - ∑F / mass • SI unit is m/s^2 • Not supported by all mobile devices
- 5. 5 Basic Algorithm • Velocity = Velocity0 + Acceleration x ∆Time • Displacement = Velocity x ∆Time • Adjust screen content on x and y axis to counter sensor- reported acceleration (opposite direction)
- 6. 6 Deficiencies • Noises in sensor-reported acceleration values • Content moving out of screen boundary • Human perception/tolerance of content displacement ≠ physical screen displacement • Deceleration may cause unwanted position adjustment • Different shaking scenarios requires different adjustment parameters
- 7. 7 Techniques • Acceleration filtering – Utilized in this and previous projects – Parameters adjustable in this project; fixed in previous projects • Boundary adjustment range – Utilized in this and previous projects • Displacement value tuning – Utilized in this and previous projects – Parameters adjustable in this project; fixed in previous projects • Adjustment freezing period – Utilized only in this project • Different parameters for different shaking scenarios – Utilized only in this project
- 8. 8 Implementation • Android OS version ? • Samsung Galaxy 7 ? • Java 1.8 • Android webview as embedded browser • Adjust webview’s left and top positions
- 9. 9 Further Improvement • Optimize algorithm parameters for more shaking scenarios • Automatically recognize different device shaking scenarios to use different algorithm parameters • Improve device CPU processing speed to minimize reaction delays • Embed screen stabilization code at OS layer
- 10. 10 Scenario Recognition • Simple linear regression • Least squares estimates for best fitting function • Experimental phase: collect data to set up model • Runtime phase: compare runtime data with model • Pick scenario whose model has smallest ∆ with runtime data
- 11. 11 References • Ruslan Yanchyshyn No Shake: Screen Stabilization in Android https://blog.lemberg.co.uk/no-shake-screen-stabilization-android (2016) • Kevin Jeisy Walking with your Smartphone: Stabilizing Screen Content ftp://ftp.tik.ee.ethz.ch/pub/students/2014-FS/SA-2014- 22.pdf (2014) • Ahmad Rahmati, Clayton Shepard, Lin Zhong NoShake: Content Stabilization for Shaking Screens of Mobile Devices http://www.ahmad.rahmati.com/papers/09.PerCom.NoShake.pdf (2009) • PennState Eberly College of Science, STAT 501 Regression Methods https://onlinecourses.science.psu.edu/stat501/node/250 (2018)
- 12. Questions