Method and apparatus for scaling down a bayer domain image

An image processor, comprising:

• a central processing unit (CPU) core;
• and
• a scaling engine coupled to the CPU core, the scaling engine capable of performing a method of scaling down a Bayer domain image made up of a number of 2×2 basic units, each having a Red (R) pixel, a Blue (B) pixel, and two green (C) pixels arranged in a fixed configuration and replicated throughout the image, the method comprising:
• partitioning the image into 2M×2N input blocks, where M and N are integers greater than or equal to 1;
• for each 2M×2N input block,
• averaging a selection of R pixels in the block to produce a R pixel in a scaled down image corresponding to the Bayer domain image;
• averaging a selection of B pixels in the block to produce a B pixel in the scaled down image;
• and
• partitioning the 2M×2N input block into first and second triangular regions, and averaging a selection of pixels in the first triangular region to produce a first G pixel in the scaled down image, and averaging a selection of pixels in the second triangular region to produce a second G pixel in the scaled down image.

An image processing system, comprising:

• an image sensor;
• and
• an image processor to process data from the image sensor, the image processor comprising a central processing unit (CPU) core;
• and a scaling engine coupled to the CPU core, the scaling engine capable of performing a method of scaling down a Bayer domain image made up of a number of 2×basic units, each having a Red (R) pixel, a Blue (B) pixel, and two green (G) pixels arranged in a fixed configuration and replicated throughout the image, the method comprising:
• partitioning the image into 2M×2N input blocks, where M and N are integers greater than or equal to 1;
• for each 2M×2N input block,
• averaging a selection of R pixels in the block to produce a R pixel in a scaled down image corresponding to the Bayer domain image;
• averaging a selection of B pixels in the block to produce a B pixel in the scaled down image;
• and
• partitioning the 2M×2N input block into first and second triangular regions, and averaging a selection of pixels in the first triangular region to produce a first G pixel in the scaled down image, and averaging a selection of pixels in the second triangular region to produce a second G pixel in the scaled down image.

A computer readable recordable type medium having stored thereon, a sequence of instructions which when executing by a processing system, cause the processing system to perform a method for scaling down a Bayer domain image made up of a number of 2×2 basic units, each having a Red (R) pixel, a Blue (B) pixel, and two green (G) pixels arranged in a fixed configuration and replicated throughout the image, the method comprising:

• partitioning the image into 2M×2N input blocks, where M and N are integers greater than or equal to 1;
• for each 2M×2N input block,
• averaging a selection of R pixels in the block to produce a R pixel in a scaled down image corresponding to the Bayer domain image;
• averaging a selection of B pixels in the block to produce a B pixel in the scaled down image;
• and
• partitioning the 2N×2N input block into first and second triangular regions, and averaging a selection of pixels in the first triangular region to produce a first G pixel in the scaled down image, and averaging a selection of pixels in the second triangular region to produce a second G pixel in the scaled down image.

An image processor, comprising:

• a central processing unit (CPU) core;
• and
• a scaling engine coupled to the CPU core, the scaling engine capable of performing a method of scaling down a Bayer domain image to produce a scaled down image comprising a repeating pattern of a 2×2 basic pixel block having four color pixels, the method comprising:
• defining an area of support comprising first and second triangular regions in the Bayer domain input image for each color pixel of each 2×2 basic pixel block in the scaled down image, each area of support including pixels of the Bayer domain image that are spatially related to the color pixel;
• and
• generating each color pixel for each 2×2 basic pixel block in the output image by averaging a selection of pixels of the Bayer domain image within the area of support for the color pixel.

An image processing system, comprising:

• an image sensor;
• and
• an image processor to process data from the image sensor, the image processor comprising a central processing unit (CPU) core;
• and a scaling engine coupled to the CPU core, the scaling engine capable of performing a method for processing a Bayer domain image to produce a scaled down image comprising a repeating pattern of a 2×2 basic pixel block having four color pixels, the method comprising:
• defining an area of support comprising first and second triangular regions in the Bayer domain input image for each color pixel of each 2×2 basic pixel block in the scaled down image, each area of support including pixels of the Bayer domain image that are spatially related to the color pixel;
• and
• generating each color pixel for each 2×2 basic pixel block in the output image by averaging a selection of pixels of the Bayer domain image within the area of support for the color pixel.