A process and system automatically tracking a region-of-interest for a color correction system

Abstract

A system and methods for creating user definable windows for applying image processing, particularly useful in a post-production color correction equipment. The system allows a user of an image processing system such as a scene by scene color corrector to define a color region of interest in an image for purposes of applying image processing only to the region of interest, with automatic tracking of that region of interest over a plurality of frames in a scene. The user defined window, comprising a closed polygon, is converted on a frame-by-frame basis to a matte that is keyed with image processing such as color correction values. The user defined windows can be edited and stored and recalled for use in other frames. The color region of interest is automatically tracked from a beginning frame to the ending frame of a scene, with a vector window defined for each frame, so as to adapt to and compensate for changes in shape, size, and geometry of the region of interest during the succession of frames in the scene.

1 . A computer-implemented process for defining a selected region of a second image from a user defined window corresponding to a selected region of a first image, comprising the steps of: 
 determining a seed point in the second image corresponding to the selected region of the first image;    determining a calculated parameter corresponding to attributes of the selected region of the first image;    starting at a point in the second image associated with the seed point, searching according to a predetermined methodology for picture elements that fall within a predetermined range of the calculated parameter;    defining a boundary in the second image based on a point in the second image at which the located picture elements fall outside of the predetermined range of the calculated parameter;    vectorizing the boundary to derive a user defined window defining the selected region of the second image.    
   
   
       2 . The process of  claim 1 , wherein the calculated parameter comprises the mean of the color value of the selected one or more picture elements.  
   
   
       3 . The process of  claim 2 , wherein the type of calculated parameter is selected from the group comprising hue, saturation, luminance, and RGB.  
   
   
       4 . The process of  claim 3 , wherein the color value of the selected one or more picture elements comprises the red (R), green (G), and blue (B) color values in an RGB color representation.  
   
   
       5 . The process of  claim 1 , wherein the predetermined range of the calculated parameter comprises a user selectable variance.  
   
   
       6 . The process of  claim 1 , wherein the step of vectorizing comprises drawing a continuous polygon drawn around the boundary, the continuous polygon comprising a predetermined number of points specified by the user.  
   
   
       7 . The process of  claim 1 , further comprising the step of: in response to user commands, editing characteristics of the user defined window to allow the user to adapt the window to the image.  
   
   
       8 . The process of  claim 1 , further comprising the step of defining a plurality of user defined windows corresponding to a plurality of regions in the second image.  
   
   
       9 . The process of claim  66 , further comprising the step of applying image processing to the selected region of the second image.  
   
   
       10 . The process of  claim 9 , wherein the image processing is selected from the group color correction, image compression, noise reduction, colorization, and animation.  
   
   
       11 . The process of  claim 1 , wherein the step of determining a seed point comprises determining a point that corresponds to the center of gravity of the selected region of the first image.  
   
   
       12 . A system for defining a selected region of a second image from a user defined window corresponding to a selected region of a first image, comprising the steps of: 
 a component for determining a calculated parameter corresponding to attributes of the selected region of the first image;    a component for determining a calculated parameter corresponding to attributes of the selected region of the first image;    a searching component operative for, starting at a point in the second image associated with the seed point, searching for picture elements that fall within a predetermined range of the calculated parameter;    a component for defining a boundary in the second image based on a point in the second image at which the located picture elements fall outside of the predetermined range of the calculated parameter; and    a vectorizing component for vectorizing the boundary to derive a user defined window defining the selected region of the second image.    
   
   
       13 . The system of  claim 12 , wherein the calculated parameter comprises the mean of the color value of the selected one or more picture elements.  
   
   
       14 . The system of  claim 13 , wherein the type of calculated parameter is selected from the group comprising hue, saturation, luminance, and RGB.  
   
   
       15 . The system of  claim 13 , wherein the color value of the selected one or more picture elements comprises the red (R), green (G), and blue (B) color values in an RGB color representation.  
   
   
       16 . The system of  claim 12 , wherein the predetermined range of the calculated parameter comprises a user selectable variance.  
   
   
       17 . The system of  claim 12 , wherein the vectorizing component is operative for drawing a continuous polygon drawn around the boundary, the continuous polygon comprising a predetermined number of points specified by the user.  
   
   
       18 . The system of  claim 12 , further user control that allow operator editing of characteristics of the user defined window to allow the user to adapt the window to the image.  
   
   
       19 . The system of  claim 12 , wherein the system is operative for defining a plurality of user defined windows corresponding to a plurality of regions in the second image.  
   
   
       20 . The system of  claim 12 , further comprising a component for applying image processing to the selected region of the second image.  
   
   
       21 . The system of  claim 20 , wherein the image processing is selected from the group color correction, image compression, noise reduction, colorization, and animation.