Techniques for improving stereo block matching with the pyramid method

Abstract

Techniques to determine a search range for a stereo based matching pyramid. A first disparity estimation value for a first level in a stereo based matching pyramid based on an image may be received. A search range for a second level may be determined using the first disparity estimation value. The search range based on a pyramid level of a second level may be increased. The search range may be increased based on a pyramid level of the second level. A second disparity estimation value may be selected from the search area for the second level. A depth map for the second level may be determined based on the second disparity estimation value. Other embodiments are described and claimed.

1 . An article of manufacture comprising a storage medium containing instructions that when executed cause a system to:
 receive a first disparity estimation value for a first level in a stereo based matching pyramid based on an image;   determine a search range for a second level based on the first disparity estimation value;   increase the search range based on a pyramid level of the second level; and   select a second disparity estimation value from the search range for the second level.   
     
     
         2 . The article of manufacture of  claim 1 , comprising instructions that when executed cause the system to determine a depth map for the second level based on the second disparity estimation value. 
     
     
         3 . The article of manufacture of  claim 1 , comprising instructions that when executed cause the system to:
 calculate a Laplacian value; and   determine the search range within the second level based on the Laplacian value.   
     
     
         4 . The article of manufacture of  claim 1 , comprising instructions that when executed cause the system to select the second disparity estimation value based on a correlation score. 
     
     
         5 . The article of manufacture of  claim 1 , comprising instructions that when executed cause the system to determine that a second level image on the second level includes a thin object that was not included on a first level image on the first level. 
     
     
         6 . The article of manufacture of  claim 1 , comprising instructions that when executed cause the system to select the second disparity estimation value based on a sum of absolute differences on a gradient times an absolute difference of a gray. 
     
     
         7 . The article of manufacture of  claim 1 , comprising instructions that when executed cause the system to select the second disparity estimation value based on a local binary pattern. 
     
     
         8 . An apparatus, comprising:
 a processing unit; and   a pyramid level search range component operatively coupled to the processing unit to:
 determine a search range for a second level based on a first disparity estimation value from a first level; 
 increase the search range based on a pyramid level of the second level; and 
 select a second disparity estimation value from the search range for the second level. 
   
     
     
         9 . The apparatus of  claim 8 , comprising:
 a digital display operatively coupled to the processing unit.   
     
     
         10 . The apparatus of  claim 8 , comprising:
 a pixel search range component to:
 calculate a Laplacian value; and 
 determine the search range within the second level based on the Laplacian value. 
   
     
     
         11 . The apparatus of  claim 8 , comprising:
 a pixel search range component to:
 determine that a target object is in the search range for the second level; 
 determine that the target object is not presented in the first level; and 
 increase the search range within the second level. 
   
     
     
         12 . The apparatus of  claim 8 , comprising:
 a pixel search range component to increase the search range within the second level when the search range comprises edges.   
     
     
         13 . The apparatus of  claim 8 , comprising:
 a correlation component to determine a correlation score based on a sum of absolute differences on a gradient times an absolute difference of a gray.   
     
     
         14 . The apparatus of  claim 8 , comprising:
 a correlation component to determine a correlation score based on a local binary pattern.   
     
     
         15 . A method, comprising:
 receiving a first disparity estimation value for a first level in a stereo based matching pyramid based on an image;   determining a search range for a second level based on the first disparity estimation value;   increasing the search range based on a pyramid level of a second level;   selecting a second disparity estimation value from the search range for the second level; and   determining a depth map for the second level based on the second disparity estimation value.   
     
     
         16 . The method of  claim 15 , comprising:
 calculating a Laplacian value; and   determining the search range within the second level based on the Laplacian value.   
     
     
         17 . The method of  claim 15 , comprising:
 selecting a second disparity estimation value from the search range for the second level based on a correlation score.   
     
     
         18 . The method of  claim 15 , comprising:
 increasing the search range within the second level when the search range comprises edges.   
     
     
         19 . The method of  claim 15 , comprising:
 determining a correlation score based on a sum of absolute differences on a gradient times an absolute difference of a gray.   
     
     
         20 . The method of  claim 15 , comprising:
 determining a correlation score based on a local binary pattern.   
     
     
         21 . A system, comprising:
 a processing unit;   a memory to store a depth extraction application;   an operating system to load the stereo block matching pyramid application on the processing unit, the stereo block matching pyramid application operative on the processing unit to:
 determine a search range for a second level based on the first disparity estimation value; 
 increase the search range based on a pyramid level of a second level; 
 select a second disparity estimation value from the search range for the second level, and 
 determine a depth map for the second level based on the second disparity estimation value; and 
   an interface to communicate information between the processing unit and the operating system.   
     
     
         22 . The system of  claim 21 , comprising a pixel search range component in the stereo block matching application operating on the processing unit to:
 determine that a target object is in the search range for the second level;   determine that the target object is not presented in the first level; and   increase the search range within the second level.   
     
     
         23 . The system of  claim 21 , comprising a pixel search range component in the stereo block matching application operating on the processing unit to:
 increase the search range within the second level when the search range comprises edges.   
     
     
         24 . The system of  claim 21 , comprising a correlation component in the stereo block matching application operating on the processing unit to:
 determine a correlation score based on a sum of absolute differences on a gradient times an absolute difference of a gray.   
     
     
         25 . The system of  claim 21 , comprising a correlation component in the stereo block matching application operating on the processing unit to:
 determine a correlation score based on a local binary pattern.