Method and system for displaying an image

Abstract

A method and system for displaying an image, includes steps and means for: storing image data in a manner that enables retrieval of different spatial regions of an image at different fidelities; determining an viewer's point of gaze on a display; retrieving image data for each spatial region of an image at a fidelity that is a decreasing function of the distance of the regions from the point of gaze; and displaying the retrieved image data on the display;

What is claimed is:  
     
         1 . A method for displaying an image, comprising the steps of: 
 a) storing image data in a manner that enables retrieval of different spatial regions of an image at different fidelities;    b) determining an viewer's point of gaze on a display;    c) retrieving image data for each spatial region of an image at a fidelity that is a decreasing function of the distance of the region from the point of gaze; and    d) displaying the retrieved image data on the display;    
     
     
         2 . The method claimed in  claim 1 , wherein the function is derived from an eccentricity dependent model of the contrast threshold function of the human visual system.  
     
     
         3 . The method claimed in  claim 1 , wherein the size of the highest fidelity portion of the image is varied as a function of the accuracy of point of gaze determination.  
     
     
         4 . The method claimed in  claim 1 , wherein the decreasing function is also dependent upon the retrieval rate of the image data.  
     
     
         5 . The method claimed in  claim 1 , further including the step of the viewer adjusting the fidelity of the image to obtain lower display update rates or smaller fields of view when the retrieval rate of image data is limited.  
     
     
         6 . The method claimed in  claim 1 , wherein the decreasing function is also a function of the viewer's viewing distance.  
     
     
         7 . The method claimed in  claim 1 , wherein the decreasing function is also a function of the ambient display environment.  
     
     
         8 . The method claimed in  claim 1 , wherein the decreasing function is also a function of one or more display characteristics selected from the group comprising display resolution, maximum display luminance; minimum display luminance; display reflectance; and display size.  
     
     
         9 . The method claimed in  claim 1 , wherein the step of determining an viewer's point of gaze includes determining the points of gaze for a plurality of viewers and retrieving and displaying image data as a function of the plurality of points of gaze.  
     
     
         10 . The method claimed in  claim 1 , wherein the point of gaze of an viewer is determined by tracking an viewer's point of gaze with an eye tracking device.  
     
     
         11 . The method claimed in  claim 1 , wherein the point of gaze of an viewer is determined by estimating the point of gaze from the image content.  
     
     
         12 . The method claimed in  claim 1 , wherein the point of gaze of an viewer is determined by measuring the points of gaze of a plurality of viewers of an image and determining the point of gaze as a function of the measured points.  
     
     
         13 . The method claimed in  claim 1 , further comprising the steps of compressing the image data prior to storage and decompressing the retrieved image data prior to display.  
     
     
         14 . The method claimed in  claim 13 , wherein the compressed image data is compressed using wavelet based compression.  
     
     
         15 . The method claimed in  claim 13 , wherein the compressed image data is compressed using Gaussian pyramid based compression.  
     
     
         16 . A method for processing a digital image, comprising the steps of: 
 a) determining a plurality of likely points of gaze on the image; and    b) processing the digital image such that each spatial region of the image is represented at a fidelity that is a decreasing function of the distance of each region from the likely points of gaze.    
     
     
         17 . The method claimed in  claim 16 , wherein the likely points of gaze are determined by measuring the points of gaze of a plurality of viewers of the image and determining the points of gaze as a function of the measured points.  
     
     
         18 . The method claimed in  claim 16 , wherein the likely points of gaze are determined by estimating the points of gaze from the image content.  
     
     
         19 . The method claimed in  claim 16 , wherein the likely points of gaze are determined by tracking one or more viewer's points of gaze with an eye tracking device.  
     
     
         20 . The method claimed in  claim 16 , wherein the decreasing function is derived from an eccentricity dependent model of the contrast threshold function of the human visual system.  
     
     
         21 . The method claimed in  claim 16 , wherein the size of the highest fidelity portion of the image is varied as a function of the accuracy of point of gaze determination.  
     
     
         22 . The method claimed in  claim 16 , wherein the decreasing function is also a function of a viewing distance.  
     
     
         23 . The method claimed in  claim 16 , further comprising the step of compressing the image data after processing.  
     
     
         24 . The method claimed in  claim 23 , wherein the compressed image data is compressed using wavelet based compression.  
     
     
         25 . The method claimed in  claim 23 , wherein the compressed image data is compressed using Gaussian pyramid based compression.  
     
     
         26 . An image display system, comprising: 
 a) a memory containing image data stored in a manner that enables retrieval of different spatial regions of an image at different fidelities;    b) a display for displaying image data retrieved from the memory;    c) means for determining an viewer's point of gaze on a display; and    d) means for retrieving image data for each spatial region of an image at a fidelity that is a decreasing function of the distance of the region from the point of gaze and providing the image data to the display.    
     
     
         27 . The system claimed in  claim 26 , wherein the function is derived from an eccentricity dependent model of the contrast threshold function of the human visual system.  
     
     
         28 . The system claimed in  claim 26 , wherein the size of the highest fidelity portion of the image is varied as a function of the accuracy of point of gaze determination.  
     
     
         29 . The system claimed in  claim 26 , wherein the decreasing function is also dependent upon the retrieval rate of the image data.  
     
     
         30 . The system claimed in  claim 26 , further including means for allowing the viewer to adjust the fidelity of the image to obtain lower display update rates or smaller fields of view when the retrieval rate of image data is limited.  
     
     
         31 . The system claimed in  claim 26 , wherein the decreasing function is also a function of the viewer's viewing distance.  
     
     
         32 . The system claimed in  claim 26 , wherein the decreasing function is also a function of the ambient display environment.  
     
     
         33 . The system claimed in  claim 26 , wherein the decreasing function is also a function of one or more display characteristics selected from the group comprising display resolution, maximum display luminance; minimum display luminance; display reflectance; and display size.  
     
     
         34 . The system claimed in  claim 26 , wherein the means for determining an viewer's point of gaze determines the points of gaze for a plurality of viewers.  
     
     
         35 . The system claimed in  claim 26 , wherein the means for determining comprises an eye tracking device.  
     
     
         36 . The system claimed in  claim 26 , wherein the means for determining comprises means for analyzing the image content and estimating the point of gaze from the image content.  
     
     
         37 . The system claimed in  claim 26 , wherein the means for determining comprises means for measuring the points of gaze for a plurality of viewers of an image and determining the point of gaze as a function of the measured points.  
     
     
         38 . The system claimed in  claim 26 , further comprising means for compressing the image data.  
     
     
         39 . The system claimed in  claim 26 , wherein the means for compressing employs wavelet based compression.  
     
     
         40 . The system claimed in  claim 26 , wherein the means for compressing employs Gaussian pyramid based compression.  
     
     
         41 . A system for processing a digital image, comprising: 
 a) means for determining a plurality of likely points of gaze on the image; and    b) means for processing the digital image such that each spatial region of the image is represented at a fidelity that is a decreasing function of the distance of the region from the likely points of gaze.    
     
     
         42 . The system claimed in  claim 41 , wherein the likely points of gaze are determined by measuring the points of gaze of a plurality of viewers of an image and determining the points of gaze as a function of the measured points.  
     
     
         43 . The system claimed in  claim 41 , wherein the likely points of gaze are determined by estimating the points of gaze from the image content.  
     
     
         44 . The system claimed in  claim 41 , wherein the likely points of gaze are determined by tracking one or more viewer's points of gaze with an eye tracking device.  
     
     
         45 . The system claimed in  claim 41 , wherein the decreasing function is derived from an eccentricity dependent model of the contrast threshold function of the human visual system.  
     
     
         46 . The system claimed in  claim 41 , wherein the size of the highest fidelity portion of the image is varied as a function of the accuracy of point of gaze determination.  
     
     
         47 . The system claimed in  claim 41 , wherein the decreasing function is also a function of a viewing distance.  
     
     
         48 . The system claimed in  claim 41 , further comprising means for compressing the image data after processing.  
     
     
         49 . The system claimed in  claim 48 , wherein the means for compressing employs wavelet based compression.  
     
     
         50 . The system claimed in  claim 48 , wherein the means for compressing employs Gaussian pyramid based compression.  
     
     
         51 . The method claimed in  claim 1 , further comprising the steps of detecting a viewer's eye movement and predicting a subsequent point of gaze based on the velocity and acceleration of the viewer's eye movement and increasing the fidelity of the image data for the subsequent point of gaze.  
     
     
         52 . The system claimed in  claim 26 , further comprising means for detecting a viewer's eye movement and predicting a subsequent point of gaze based on the velocity and acceleration of the viewer's eye movement and means for increasing the fidelity of the image data for the subsequent point of gaze.