CAD/Graphics 2013, Hong Kong An Image-space Energy-saving Visualization Scheme for OLED Displays Haidong Chen 1, Ji Wang 2, Weifeng Chen 3, Huamin Qu 4,

CAD/Graphics 2013, Hong Kong

An Image-space Energy-saving Visualization Scheme for OLED Displays

Haidong Chen1, Ji Wang2, Weifeng Chen3, Huamin Qu4, Wei Chen1

1Zhejiang University, CHINA, 2Virginia Tech, U.S., 3Zhejiang University of Finance & Economics, CHINA,

4Hong Kong Universityof Science and Technology, HONGKONG

2

Background

CAD/Graphics 2013 Hong Kong

LCD Display OLED Display• High-intensity backlight• Consume a constant energy

• Self-emissive• Energy consumption is

dependent on the shown content

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Current Energy Reduction Techniques

• Device-level – Dynamic voltage scaling [Shin et al. 2011]

• Context-aware Dimming – Tracking user interactions and behaviors

[Moshnyaga et al. 2005, Betts-LaCroix 2010]• Color Remapping– Changing color [Chuang et al. 2009, Wang et al.

2012, Dong et al. 2012]

CAD/Graphics 2013Hong Kong

Neglect the issue of perceptual quality loss

Not feasible to many applications

4

Our Contributions• An adaptive color dimming scheme– Energy reduction– Minimization of perceptual quality loss

• A GPU-friendly visual saliency computation algorithm


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Two Observations• Dimming remains an effective energy saving

scheme• Perceptual quality loss can be remedied by

explicit highlighting visual salient features


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Our Approach


The pipeline of our approach

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Our ApproachStep1: Suppress undesired details (Abstraction)


Solved with the bilateral grid data structure [Chen et al. 2007]

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Our ApproachStep2: Compute edge-oriented saliency map


Visually salient feature detector:

Saliency map:

S (p) = (1− τ) Md(p) + τMc(p)

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Our ApproachStep3: Dimming


Energy-saving result

Input

AbstractedSaliency map

Dimming function:

Preservation of details Global luminance

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Experiments• Measuring energy consumption model


[Dong et al. 2012]

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Experiments• 3D volumetric data visualization

α=0.65 β=0.75


Original Simulated uniform dimming16.1% energy reduction

Our result17.9% energy reduction

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Experiments• 2D geo visualization

α=0.75 β=0.5


Original Our result642.2% energy reduction

Simulated uniform dimming63.7% energy reduction

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Experiments• Performance– Collected from a PC with NV GTX580, Intel Core2

Duo3.0GHz CPU, 4GB host memory


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User Study• 24 Participants– Age 22-29; 9 females, 15 males; 4 undergraduates,

20 graduate students


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User Study• Tasks– [T1] Visual Search• Identify “street map” in the maps processed with three

schemes (NC: normal color scheme; SGD: our saliency guided color scheme; UD: simulated uniform dimming scheme )• 8 participants for each scheme• 2 trials for each participants


Given street map

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User Study• Tasks– [T2] Preference Ranking• Criterion: clarity, local contrast, blurriness, energy

consumption• Rank each image with 1st, 2nd, 3rd


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User Study• Result analysis– Completion time


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User Study• Result analysis– Preference ranking for Geo-Vis application


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User Study• Result analysis– Preference ranking for volumetric data vis


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Conclusions• Introduce a novel saliency-guided color

dimming scheme for OLED displays– simultaneous saving energy consumption and

improving perceptual quality los issue• A preliminary user study to testify the

acceptance of our method


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Acknowledgements• This work is partially supported by the NSF of

China (61003193), the National High Technology Research and Development Program of China (2012AA12090), the Major Program of National Natural Science Foundation of China (61232012), and the National Natural Science Foundation of China (81172124).


22

Thanks


Original Simulated uniform dimming16.1% energy reduction

Our result17.9% energy reduction

Documents

CAD/Graphics 2013, Hong Kong An Image-space Energy-saving Visualization Scheme for OLED Displays Haidong Chen 1, Ji Wang 2, Weifeng Chen 3, Huamin Qu 4,