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Mindreading Machines Rana El Kaliouby and Peter Robinson Contact: [email protected] www.cl.cam.ac.uk/~re227 RTV4HCI 2004

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Page 1: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

Outline

Mindreading Machines

Rana El Kaliouby and Peter Robinson

Contact: [email protected]

www.cl.cam.ac.uk/~re227

RTV4HCI 2004

Page 2: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Mindreading Machines

Mindreading: is the ability to attribute mental states to others given non-verbal communication cues (e.g. Baron-Cohen et. Al, 1996)

Essential to understanding behaviour, predicting actions in a social environment

AutomatedMindreading

System

Video of the face

A mental state class

intention-aware, context-aware

technology

Page 3: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

More faces?!! What’s new?Mindreading Inferring Cognitive

Mental StatesApplicationsExperimental

EvaluationConclusions

Inspiring progress on automated facial expression analysis

Mostly on automated facial action analysisOr recognition of the set of basic emotions

Beyond the basic emotions:

complex (cognitive) mental states

Page 4: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Complex Mental StatesMindreading Inferring Cognitive

Mental StatesApplicationsExperimental

EvaluationConclusions

• Agreement

(convinced, committed, encouraging, persuaded, agreeing, decided,

sure, willing)

• Concentrating(absorbed, concentrating)

• Disagreement(contradictory, disagreeing, discouraging, disapproving)

• Interested(interested, asking)

• Thinking(brooding, calculating, thinking, thoughtful, fantasizing, choosing)

• Unsure(confused, baffled, puzzled, unsure, undecided)

Page 5: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Complex Mental States

Why?more frequent (Rozin and Cohen, Emotion 2003)

play an important role in predicting people’s intentions and actions than basic emotions (Baron-Cohen, 2001)

Do we need a different approach?(El Kaliouby, Robinson and Keates HCII 2003)

Multiple asynchronous information sourcesMulti-level temporal abstractions (real time at 29fps)

Page 6: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

The mindreading DVD

• 412 mental states (or emotions)• 6 videos per mental state• 24 groups

• meta-groups• fine shades of the same mental state

• Posed• Most comprehensive, labelled dataset available•Resolution: 320x240• duration 6-8sec

• Variables:• 20 different actors• varying head + body pose• doesn’t start with a neutral

• http://www.jkp.com/mindreading/

Mindreading DVD (Jessica Kingsley Publishers), courtesy of the Autism Research Centre, University of Cambridge

Page 7: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

AutomatedMindreadingSystem

Page 8: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Overview

Facial feature extraction

Feature point tracking

Head pose estimation

Head & facial action unit recognition

Head & facial display recognition

Mental state inference

Hmm … Let me think about this

Page 9: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Head Pose Estimation

Use expression-invariant feature points to estimate pitch (50°), yaw(50°) and roll(30° ).Output is head action unit

Page 10: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Facial Feature ExtractionMindreading Inferring Cognitive

Mental StatesApplicationsExperimental

EvaluationConclusions

Colour, shape and motion analysis (Tian et al, 2001)

Output is facial action units (+intensity)

Aperture Teeth

Page 11: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Overview

Facial feature extraction

Feature point tracking

Head pose estimation

Head & facial action unit recognition

Head & facial display recognition

Mental state inference

Hmm … Let me think about this

Page 12: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Facial and Head Display Recognition

N o s e Tip D is p lac e me nt s ( C o nv inc e d )

-10

-5

0

5

10

15

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93 97 101 105 109 113 117 121 125 129 133 1

Fr a m e N o .

A head nod is an alternating series of head up and head down movements.

Lip corner pull

-20

0

20

40

60

80

1 10 19 28 37 46 55 64 73 82 91 100 109 118 127 136 145 154 163 172 181 190

frame no.

%in

crea

se in

dis

tanc

e

DIST(L)*RDIST(R)/RAV

Onset of a smile Smile Peak

Page 13: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Facial and Head Display RecognitionMindreading Inferring Cognitive

Mental StatesApplicationsExperimental

EvaluationConclusions

Left-right HMMs 4 state, 3 symbols for nod, shake, mouth displays2 state, 7 symbol for tilt, turn displays

Page 14: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Facial and Head Display Recognition

TrainingMaximum likelihood training30-50 samples for each head/facial display

Page 15: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Facial and Head Display Recognition

Evaluation (12900 frames)• Live demo:

• Royal Institution of Great Britain (Feb 2004)• CVPR

Page 16: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Complex Mental State InferenceMindreading Inferring Cognitive

Mental StatesApplicationsExperimental

EvaluationConclusions

Facial feature extraction

Feature point tracking

Head pose estimation

Head & facial action unit recognition

Head & facial display recognition

Mental state inference

Hmm … Let me think about this

Page 17: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Complex Mental State Inference*

Mindreading Inferring Cognitive Mental States

ApplicationsExperimental Evaluation

Conclusions

Dynamic Bayesian Networks (DBNs)A model per mental state

Hidden mental state

Ct

Nod

Teeth

Nod

Teeth

Smile

Observeddisplays

Ct+1

Turn Smile Turn

*

Page 18: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Complex Mental State Inference

Parameter learningMaximum likelihood estimatesAround 270 samples per classDiscriminative power of display d for each mental state m:

Interested Thinking

ConcentratingAgreement

Disagreement Unsure

Page 19: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Complex Mental State Inference

Structure learningFor each mental state find optimal subset of displaysSequential backward elimination

Page 20: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Complex Mental State Inference

Structure learning

Page 21: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Complex Mental State Inference

InferenceJunction tree inferenceForward-backward algorithm

Page 22: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Accumulating symbolsMental state (DBN)

Facial/Head display (HMM)

Facial/Head AU

Frame

Page 23: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Tying it altogether: Multi-level Temporal Abstraction

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Accumulating symbolsMental state (DBN)

Facial/Head display (HMM)

Facial/Head AU

Frame

Page 24: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Accumulating symbolsMental state (DBN)

Facial/Head display (HMM)

Facial/Head AU

Frame

Page 25: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Accumulating symbolsMental state (DBN)

Facial/Head display (HMM)

Facial/Head AU

Frame

Page 26: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Accumulating symbolsMental state (DBN)

Facial/Head display (HMM)

Facial/Head AU

Frame

Page 27: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

Accumulating HMM evidence

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 28: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

Accumulating HMM evidence

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 29: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

Accumulating HMM evidence

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 30: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

Accumulating HMM evidence

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 31: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

Accumulating HMM evidence

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 32: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

DBN inference

Accumulating HMM evidence

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 33: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

HMM evidenceSliding window

DBN inference

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 34: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

DBN inference

HMM evidenceSliding window

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 35: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

DBN inference

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

HMM evidenceSliding window

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 36: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

HMM evidenceSliding window

DBN inference

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 37: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

HMM evidenceSliding window

DBN inference

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

Symbol sliding windowMental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 38: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Multi-level Temporal Abstraction

60 65 70 75 80 85 90 95 100 105

HMM evidenceSliding window

DBN inference

5 10 15 20 25 30 35 40 45 50 55

Symbol sliding window Mental state (DBN)

Facial/head display (HMM)

Facial/head AU

Frame

Page 39: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

ExperimentalEvaluation

Mindreading DVD (Jessica Kingsley Publishers), courtesy of the Autism Research Centre, University of Cambridge

Page 40: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Demo: test yourself!!

Mindreading Inferring Cognitive Mental States

ApplicationsExperimental Evaluation

Conclusions

Can you guess which group the video belongs to?AgreementConcentratingDisagreementInterestedThinkingUnsure

video

Page 41: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Demo: test the mindreading machine!!

Objective: calculate a probability for each mental stateGiven: evidence nodesColour coding Notes:

previous states affect current onesLikelihoods do not add up to 100% (not mutually exclusive)

Demo

Opent

Unsuret43%

Unsuret-152%

Nodt

Smilet

Puckert

Thinkingt86%

Turnt

PuckertNodt

Thinkingt-182%

Shaket

Tiltt

0 10020 40 60 80

Likelihood legend(%)

Page 42: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Demo: The results

Mindreading Inferring Cognitive Mental States

ApplicationsExperimental Evaluation

Conclusions

This was a video of choosing (thinking group)

-0.1

0.1

0.3

0.5

0.7

0.9

1.1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Inference instance

Men

tal s

tate

like

lihoo

d AgreementDisagreementThinkingComprehendingConcentratingUnsureInterested

Page 43: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Experimental ResultsMindreading Inferring Cognitive

Mental StatesApplicationsExperimental

EvaluationConclusions

Group Mental State #videos %CorrectAgreement Assertive 3 66.7

Committed 5 100Convinced 4 100Decided 4 50Encouraging 3 100Sure 4 100Willing 2 100Total 25 88.1

Concentrating Absorbed 4 100Concentrating 6 100Total 10 100

Disagreement Contradictory 3 100Disapproving 5 40Discouraging 5 100Total 13 80

Interested Asking 5 80Interested 5 100Total 10 90

Thinking Brooding 3 66.7Calculating 4 75Choosing 5 100Fantasising 4 100Thinking 2 100Total 18 88.9

Unsure Baffled 6 100Confused 6 83.3Puzzled 6 83.3Undecided 6 83.3Unsure 6 100Total 30 90

106 89.5Overall Recognition Rate

Leave-5-out cross validation106 videos (12900 frames)Out of the 24 groups, currently support six (24 mental states)Leaves another 12 complex groups

Priority ones: bored, comprehendingNot really interested in: flirtatious, sneaky!

Recognition rate: 89.5% of the videos were correctly classifiedFalse positive rate for class m (given by the percentage of files misclassified as m):

• highest for agreement (16%) • lowest for thinking (0%)

Interesting ResultsMental state overlap?onset

Open questions:How well does this generalise to spontaneous (unlabelled) datasets

Page 44: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Temporal Smoothing vs. Sliding window size

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

HMM evidenceSliding window(size=10)

DBN inference

Symbol sliding window Mental state (DBN)The effect of the sliding window

size (sw) on temporal smoothing:

Large sw size: over-smoothingSmall size: spiky inferences

Facial/head display (HMM)

Facial/head symbol

Frame

Page 45: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

Conclusions Mindreading Inferring Cognitive

Mental StatesApplicationsExperimental

EvaluationConclusions

1. Mindreading machines: 1. Beyond the basic emotions!2. Fully automated3. Supports moderate out of plane head motion

2. We tried only one possible approach ...3. Applications

To do: Cluster analysis to measure similarity / distance between the classesTry the CVPR demo data

Page 46: Is Your Machine Emotionally Intelligent?rtv4hci.rutgers.edu/04/talks/relkaliouby.pdf · RTV4HCI 2004 Mindreading Machines Mindreading: is the ability to attribute mental states to

RTV4HCI 2004

BIG thank you :)

A BIG thank you to everyone who took part in our demo (especially those who did some acting)