Method of selecting colors for pixels within blocks for block truncation encoding

Claim 1

A method of selecting colors to be assigned to pixels in an image, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels and each pixel has a value that represents the luminance, chrominance and hue at a discrete location in an image; identifying at least one largest pixel cluster in a block, wherein said largest pixel cluster includes a plurality of pixels that have substantially the same luminance, chrominance and hue value, and said largest pixel cluster including the largest number of pixels; designating a signal value associated with said largest pixel cluster for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster signal value; calculating an average luminance, chrominance and hue value for pixels outside of said largest pixel cluster, and designating said average outside pixel signal value for a next assignment to said block; selecting a next largest pixel cluster that includes a number of pixels second in size to said largest pixel cluster; setting a value of all pixels in said next largest pixel cluster equal to said next largest pixel cluster signal value; and in said step of calculating an average luminance, chrominance and hue value for pixels outside of said largest pixel cluster, performing said calculation for pixels outside of said largest pixel cluster and said next largest pixel cluster, and setting a value of all pixels located outside of said largest cluster and said next largest pixel cluster equal to said average luminance, chrominance and hue value.

Claim 2

A method of selecting colors to be assigned to pixels in an image, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels and each pixel has a value that represents the luminance, chrominance and hue at a discrete location in an image; identifying at least one largest pixel cluster in a block, wherein said largest pixel cluster includes a plurality of pixels that have substantially the same luminance, chrominance and hue value, and said largest pixel cluster including the largest number of pixels; designating a signal value associated with said largest pixel cluster for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster signal value; calculating an average luminance, chrominance and hue value for pixels outside of said largest pixel cluster, and designating said average outside pixel signal value for a next assignment to said block; selecting a next largest pixel cluster that includes a number of pixels second in size to said largest pixel cluster; setting a value of all pixels in said next largest pixel cluster equal to said next largest pixel cluster signal value; and in said step of calculating an average luminance, chrominance and hue value for pixels outside of said largest pixel cluster, performing said calculation for pixels outside of said largest pixel cluster and said next largest pixel cluster, and setting a value of all pixels located outside of said largest cluster and said next largest pixel cluster equal to said average luminance, chrominance and hue value.

Claim 3

A method of selecting colors to be assigned to pixels in an image, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels and each pixel has a value that represents the luminance, chrominance, and hue at a discrete location in an image; dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels and each pixel has a value that represents the luminance, chrominance and hue at a discrete location in an image; identifying at least one largest pixel cluster in a block, wherein said largest pixel cluster includes a plurality of pixels that have substantially the same luminance, chrominance and hue value, and said largest pixel cluster including the largest number of pixels; designating a signal value associated with said largest pixel cluster for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster signal value; calculating an average luminance, chrominance and hue value for pixels outside of said largest pixel cluster, and designating said average outside pixel signal value for a next assignment to said block; identifying a plurality of remaining pixel clusters, wherein each of said pixel clusters consists of a plurality of pixels that have substantially the same luminance, chrominance and hue value; sequentially ordering said remaining pixel clusters based upon a number of pixels contained therein; setting a value of all pixels in each of said remaining pixel clusters equal to a signal value of a pixel inside said respective pixel clusters; and in said step of calculating an average luminance, chrominance, and hue value for pixels outside of said largest pixel cluster, calculating an average luminance, chrominance, and hue value for pixels outside of said largest pixel cluster and said sequentially ordered pixel clusters and setting a value of all pixels located outside of said sequentially ordered pixel clusters equal to said average luminance, chrominance, and hue value.

Claim 4

A method of selecting colors to be assigned to pixels in an image, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels and each pixel has a value that represents the luminance, chrominance, and hue at a discrete location in an image; dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels and each pixel has a value that represents the luminance, chrominance and hue at a discrete location in an image; identifying at least one largest pixel cluster in a block, wherein said largest pixel cluster includes a plurality of pixels that have substantially the same luminance, chrominance and hue value, and said largest pixel cluster including the largest number of pixels; designating a signal value associated with said largest pixel cluster for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster signal value; calculating an average luminance, chrominance and hue value for pixels outside of said largest pixel cluster, and designating said average outside pixel signal value for a next assignment to said block; identifying a plurality of remaining pixel clusters, wherein each of said pixel clusters consists of a plurality of pixels that have substantially the same luminance, chrominance and hue value; sequentially ordering said remaining pixel clusters based upon a number of pixels contained therein; setting a value of all pixels in each of said remaining pixel clusters equal to a signal value of a pixel inside said respective pixel clusters; and in said step of calculating an average luminance, chrominance, and hue value for pixels outside of said largest pixel cluster, calculating an average luminance, chrominance, and hue value for pixels outside of said largest pixel cluster and said sequentially ordered pixel clusters and setting a value of all pixels located outside of said sequentially ordered pixel clusters equal to said average luminance, chrominance, and hue value.

Claim 5

A method of selecting colors to be assigned to pixels in an image, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels and each pixel has a value that represents the luminance, chrominance and hue at a discrete location in an image; identifying at least one largest pixel cluster in a block, wherein said largest pixel cluster includes a plurality of pixels that have substantially the same luminance, chrominance and hue value, and said largest pixel cluster including the largest number of pixels; designating a signal value associated with said largest pixel cluster for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster signal value; calculating an average luminance, chrominance and hue value for pixels outside of said largest pixel cluster, and designating said average outside pixel signal value for a next assignment to said block; altering said selected colors by extrapolating along a line between them to provide a form of edge enhancement.

Claim 6

A method of selecting colors to be assigned to pixels in an image, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels and each pixel has a value that represents the luminance, chrominance and hue at a discrete location in an image; identifying at least one largest pixel cluster in a block, wherein said largest pixel cluster includes a plurality of pixels that have substantially the same luminance, chrominance and hue value, and said largest pixel cluster including the largest number of pixels; designating a signal value associated with said largest pixel cluster for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster signal value; calculating an average luminance, chrominance and hue value for pixels outside of said largest pixel cluster, and designating said average outside pixel signal value for a next assignment to said block; altering said selected colors by extrapolating along a line between them to provide a form of edge enhancement.

Claim 7

A method of encoding an image at a first resolution for storing in an image buffer at a second resolution, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels; identifying a number of pixel clusters present in each of said plurality of blocks, wherein a pixel cluster includes a plurality of pixels that have substantially the same color; selecting a largest pixel cluster for each block that includes the largest number of pixels in said block and designating said largest pixel cluster color for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster color value; calculating an average color value for pixels in said block outside of said largest pixel cluster, and designating said average outside pixel color value for a next assignment to said block; storing said plurality of blocks in said reduced image buffer; selecting a next largest pixel cluster that includes a number of pixels second in size to said largest cluster; setting a value of all pixels in said largest cluster equal to said largest pixel cluster color value; and setting a value of all pixels in said next largest cluster equal to said next largest pixel cluster color value; and in said step of calculating an average color value for pixels in said block outside of said largest pixel cluster, performing said calculation for pixels in said block outside of said largest pixel cluster and said next largest color pixel cluster, and setting a value of all pixels located in said block outside of said largest pixel cluster and said next largest cluster equal to said average color value.

Claim 8

A method of encoding an image at a first resolution for storing in an image buffer at a second resolution, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels; identifying a number of pixel clusters present in each of said plurality of blocks, wherein a pixel cluster includes a plurality of pixels that have substantially the same color; selecting a largest pixel cluster for each block that includes the largest number of pixels in said block and designating said largest pixel cluster color for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster color value; calculating an average color value for pixels in said block outside of said largest pixel cluster, and designating said average outside pixel color value for a next assignment to said block; storing said plurality of blocks in said reduced image buffer; selecting a next largest pixel cluster that includes a number of pixels second in size to said largest cluster; setting a value of all pixels in said largest cluster equal to said largest pixel cluster color value; and setting a value of all pixels in said next largest cluster equal to said next largest pixel cluster color value; and in said step of calculating an average color value for pixels in said block outside of said largest pixel cluster, performing said calculation for pixels in said block outside of said largest pixel cluster and said next largest color pixel cluster, and setting a value of all pixels located in said block outside of said largest pixel cluster and said next largest cluster equal to said average color value.

Claim 9

A method of encoding an image at a first resolution for storing in an image buffer at a second resolution, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels; identifying a number of pixel clusters present in each of said plurality of blocks, wherein a pixel cluster includes a plurality of pixels that have substantially the same color; selecting a largest pixel cluster for each block that includes the largest number of pixels in said block and designating said largest pixel cluster color for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster color value; calculating an average color value for pixels in said block outside of said largest pixel cluster, and designating said average outside pixel color value for a next assignment to said block; storing said plurality of blocks in said reduced image buffer; altering said selected colors by extrapolating along a line between them to provide a form of edge enhancement.

Claim 10

A method of encoding an image at a first resolution for storing in an image buffer at a second resolution, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels; identifying a number of pixel clusters present in each of said plurality of blocks, wherein a pixel cluster includes a plurality of pixels that have substantially the same color; selecting a largest pixel cluster for each block that includes the largest number of pixels in said block and designating said largest pixel cluster color for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster color value; calculating an average color value for pixels in said block outside of said largest pixel cluster, and designating said average outside pixel color value for a next assignment to said block; storing said plurality of blocks in said reduced image buffer; altering said selected colors by extrapolating along a line between them to provide a form of edge enhancement.

Claim 11

A method of encoding an image at a first resolution for storing in an image buffer at a second resolution, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels; identifying a number of pixel clusters present in each of said plurality of blocks, wherein a pixel cluster includes a plurality of pixels that have substantially the same color; selecting a largest pixel cluster for each block that includes the largest number of pixels in said block and designating said largest pixel cluster color for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster color value; calculating an average color value for pixels in said block outside of said largest pixel cluster, and designating said average outside pixel color value for a next assignment to said block; storing said plurality of blocks in said reduced image buffer; identifying a plurality of remaining pixel clusters in said block, wherein each of said pixel clusters consists of a plurality of pixels that have substantially the same luminance, chrominance and hue value; sequentially ordering said remaining pixel clusters based upon a number of pixels contained therein; setting a value of all pixels in each of said remaining pixel clusters equal to a signal value of a pixel inside said respective pixel clusters; and in said step of calculating an average luminance, chrominance, and hue value for pixels in said block outside of said largest pixel cluster, performing said calculation for pixels in said block outside of said largest pixel cluster and said sequentially ordered pixel clusters and setting a value of all pixels located in said block and outside of said largest pixel cluster and said sequentially ordered pixel clusters equal to said average luminance, chrominance, and hue value.

Claim 12

A method of encoding an image at a first resolution for storing in an image buffer at a second resolution, the method comprising: dividing the image into a plurality of blocks wherein each block is comprised of a plurality of pixels; identifying a number of pixel clusters present in each of said plurality of blocks, wherein a pixel cluster includes a plurality of pixels that have substantially the same color; selecting a largest pixel cluster for each block that includes the largest number of pixels in said block and designating said largest pixel cluster color for an assignment to said block and setting a value of all pixels in said largest cluster equal to said largest pixel cluster color value; calculating an average color value for pixels in said block outside of said largest pixel cluster, and designating said average outside pixel color value for a next assignment to said block; storing said plurality of blocks in said reduced image buffer; identifying a plurality of remaining pixel clusters in said block, wherein each of said pixel clusters consists of a plurality of pixels that have substantially the same luminance, chrominance and hue value; sequentially ordering said remaining pixel clusters based upon a number of pixels contained therein; setting a value of all pixels in each of said remaining pixel clusters equal to a signal value of a pixel inside said respective pixel clusters; and in said step of calculating an average luminance, chrominance, and hue value for pixels in said block outside of said largest pixel cluster, performing said calculation for pixels in said block outside of said largest pixel cluster and said sequentially ordered pixel clusters and setting a value of all pixels located in said block and outside of said largest pixel cluster and said sequentially ordered pixel clusters equal to said average luminance, chrominance, and hue value.