TENNIS REAL PLAY: AN INTERACTIVE TENNIS GAME WITH MODELS FROM REAL VIDEOS JUI-HSIN LAI ET AL., NTU ACM MM 2011

THE IDEA

THE GOAL

THE CHALLENGES 1.Player Database - Auto Video Analysis - Auto Clip Collection 2.Player Rendering - Realtime Clip Editing - Player Strategy Analysis 3.The Game System - Background/Foreground Rendering - Realtime Processing

THE CHALLENGES 1.Player Database - Auto Video Analysis - Auto Clip Collection 2.Player Rendering - Realtime Clip Editing - Player Strategy Analysis 3.The Game System - Background/Foreground Rendering - Realtime Processing

PLAYER DB: FOREGROUND SEGMENTATION PROBLEM: THE FIGURES ARE NOT IN THE SAME SIZE…

SOLUTION: FIDUCIAL COORDINATE Fiducial (adj.) 基準的 (m0~m7: homography parameters, can be determined by trigonometrics)

PLAYER DB: HIT STATISTICS Jui-Hsin Lai et al., “Tennis Video 2.0: A New Presentation of Sports Videos with Content Separation and Rendering”, JVCI Forehand volley 2.Backhand volley 3.Forehand stroke 4.Backhand stroke 5.Drop shot

PLAYER DB: BEHAVIOR MODEL The final piece of the DB that combines other pieces Players speed, hit trajectory, reaction time…etc. Can create ‘virtual ’matches between players (like fantasy baseball!) kcir: In other words, the gamer actually plays minor role in this ‘game’. Whether a player can catch up (speed/direction); how does one choose to hit (force/angle), these are pre-determined.

THE CHALLENGES 1.Player Database - Auto Video Analysis - Auto Clip Collection 2.Player Rendering - Realtime Clip Editing - Player Strategy Analysis 3.The Game System - Background/Foreground Rendering - Realtime Processing

PLAYER RENDERING: CLIP SELECTION If the player decides (how?) to go from point A to point B: The system automatically choose the “suitable” clips and seam them together. Suitable: 1. shortens the distance 2. runs along the path 3. min # of clips

FROM “MOTION” TO “HIT” kcir: So the swing of the gamer is meaningless. What only matters is the timing of swing.

FROM “MOTION” TO “HIT” In order to look good: They want to use “view morphing” in between the transition PROBLEM: YOU NEED ‘LABELS’ BEFORE YOU CAN MORPH Solution: [JCV09] and [JCV04] on Auto Labeling for morphing

THE CHALLENGES 1.Player Database - Auto Video Analysis - Auto Clip Collection 2.Player Rendering - Realtime Clip Editing - Player Strategy Analysis 3.The Game System - Background/Foreground Rendering - Realtime Processing

TO CONSTRUCT 3D FROM 2D

3D GAMING (FUTURE WORK)

EVALUATION Computation Analysis Prediction of Game Result - Virtual Match Subjective Evaluation - Compares to Wii and xbox - Interactivity - Immersive Experience

COMPUTATION ANALYSIS Intel i7 2.6 GHz CPU with 4GB RAM Rendering resolution: 720 x 480 => Frame rate: 30 fps (standard mpeg1 requirement) Basis You can offline- computed these two

PREDICTION OF GAME RESULT

SUBJECTIVE EXPERIMENTS 20 undergrads 5-point scoring system Q1. Interaction Q2. Immersive Experience Q3. Interesting Q4. Innovative application (huh?) Q5. Willing to play TRP after watching videos?

SUBJECTIVE EXP: COMPARES TO OTHERS Participants played TRP, Wii tennis, and TP3 xbox Q6. Entertainment levels Q7. Realism of visual effects Q8. Interactiveness (didn't you just ask this in Q1?) Q9. Preference

RESULTS Using Wii as the comparison basis (score=3) Q1. Interaction Q2. Immersive Experience Q3. Interesting Q4. Innovative application (huh?) Q5. Willing to play TRP after watching videos? Q6. Entertainment levels Q7. Realism of visual effects Q8. Interactiveness Q9. Preference

PUBLIC DEMO People are asking: “How can I get this feature on my own TV?”

CONCLUSION 1.The first work to integrate video-based rendering and interactive sports game running in realtime 2.Without motion capture system, construct game from video without much human assistance 3.Game results can reflect the match results in real world and predict match results

COMMENTS 1.The value of this work is its auto process of video->game, which includes: - video analysis - auto editing of the clips - realtime rendering - computational complexity to overcome with 2.The game itself, although put in the title, is just a bonus 3.How can this be better than Wii !?!?!? - gamer cannot control how they hit. The hitting result is determined by the player DB. (Williams always wins) - gamer don't have to chase the ball. The player will instantly know where to go. (this is cheating!) - You will always win if you know which player to pick ….And you call this FUN? Poor consumers