Method and system for histogram calculation using a graphics processing unit

A method for histogram calculation using a graphics processing unit (GPU), comprising:

• storing input data in a two-dimensional (2D) texture domain;
• subdividing said domain into evenly sized sections;
• deriving, in parallel entirely within said GPU, a set of histograms comprising a histogram for each of said sections;
• summing said set of histograms entirely within said GPU to derive a final histogram;
• and
• wherein said step of deriving a set of histograms comprises:
• determining for each texel a corresponding bin by using texture coordinates.

A method for image histogram calculation, using a graphics processing unit (GPU), comprising:

• storing image input data in a two-dimensional (2D) texture domain;
• subdividing said domain into evenly sized sections;
• deriving, in parallel entirely within said GPU, a set of image histograms comprising a histogram for each of said sections;
• summing said set of image histograms entirely within said GPU to derive a final histogram;
• and
• wherein said step of deriving a set of image histograms comprises:
• determining for each texel a corresponding bin by using texture coordinates.

A method for histogram calculation using a graphics processing unit (GPU), comprising:

• storing image data in a two-dimensional (2D) texture domain;
• subdividing said domain into independent regions or tiles by subdividing said domain into evenly sized and independent tiles;
• calculating in parallel, in said GPU, a plurality of tile histograms, one for each tile and determining for each texel a corresponding bin by using texture coordinates by counting for each texel the occurrence of values inside its appurtenant tile for said corresponding histogram bin;
• and
• summing up in parallel, in said GPU, said tile histograms so as to derive a final image histogram, by applying a texture reduce operation by carrying out a rendering pass for halving texture size by summing the ith texel of a given histogram with the ith texel of the three tiles adjacent in a positive texture coordinate direction.

A system for histogram calculation using a graphics processing unit (GPU), comprising:

• memory means for storing a program and other data;
• and
• processor means in communication with said memory device, said processor being operative with said program to perform:
• storing image data in a two-dimensional (2D) texture domain;
• subdividing said domain into independent regions or tiles;
• calculating in parallel, entirely within said GPU, a plurality of tile histograms, one for each tile;
• summing up in parallel entirely within said GPU, said tile histograms so as to derive a final image histogram;
• and wherein
• said processor means is operative with said program to perform counting intensity in a texel determined by texel texture coordinates, the number of histogram bins, and the size of said image data.

A computer program product comprising a computer useable medium having computer program logic recorded thereon for program code for histogram calculation using a graphics processing unit (GPU), by:

• storing image data in a two-dimensional (2D) texture domain;
• subdividing said domain into independent regions or tiles;
• calculating in parallel, entirely within said GPU, a plurality of tile histograms, one for each tile;
• summing up in parallel, entirely within said GPU, said tile histograms so as to derive a final image histogram;
• and wherein:
• said step of calculating a plurality of tile histograms comprises:
• counting intensity in a texel determined by texel texture coordinates, the number of histogram bins, and the size of said image data.