Image processing device, image processing method, program, and integrated circuit

Patent metadata

Field	Value
Publication number	US-9235872-B2
Application number	US-201214131045-A
Country	US
Kind code	B2
Filing date	May 8, 2012
Priority date	Aug 11, 2011
Publication date	Jan 12, 2016
Grant date	Jan 12, 2016

Abstract

An image processing device ( 10 ) includes: a representative pixel value storage unit ( 12 ) which selects one of plural sub-pixels as a representative sub-pixel, and store, into a representative pixel value storage area, a representative pixel value which is a pixel value of the representative sub-pixel; and a sub-pixel value storage unit ( 13 ) which stores, into a sub-pixel value storage area, pixel values of sub-pixels other than the representative sub-pixel, wherein the sub-pixel value storage area stores one or more sets corresponding to N number of pixels, the one or more sets each including a pixel position and a pixel value of each sub-pixel other than the representative sub-pixel of a pixel at the pixel position, N being a natural number smaller than a total number of the plural pixels in the unit of processing for an edge determination unit ( 11 ).

First claim

The invention claimed is:

1. An image processing device for processing pixels in image data, wherein the unit size of the processing is a unit of processing including plural pixels, said image processing device comprising:
an edge determination unit configured to determine, for each of the plural pixels in the unit of processing, whether the pixel includes a predetermined edge;
a representative pixel value storage unit configured to, for each of the plural pixels, select one of plural sub-pixels obtained by dividing the pixel, as a representative sub-pixel, and store, into a representative pixel value storage area, a representative pixel value which is a pixel value of the representative sub-pixel; and
a sub-pixel value storage unit configured to store, into a sub-pixel value storage area, pixel values of two or more of the plural sub-pixels in each of pixels determined by the edge determination unit to include the predetermined edge, the two or more of the plural sub-pixels being other than the representative sub-pixel selected by the representative pixel value storage unit,
wherein the sub-pixel value storage area stores one or more sets corresponding to N number of pixels, the one or more sets each including a pixel position and a pixel value of each sub-pixel other than the representative sub-pixel of a pixel at the pixel position, N being a natural number greater than zero and smaller than a total number of the plural pixels in the unit of processing for the edge determination unit.

2. The image processing device according to claim 1 , further comprising:
a first memory which stores, as image data, pixel values of plural sub-pixels obtained by dividing each of pixels included in an image;
a second memory which includes the representative pixel value storage area and the sub-pixel value storage area;
an image processing unit configured to perform image processing on the image data stored in the first memory; and
a transfer unit configured to transfer at least a portion of the image data stored in the first memory between the first memory and the second memory, the transfer unit including:
the edge determination unit;
the representative pixel value storage unit; and
the sub-pixel value storage unit.

3. The image processing device according to claim 1 ,
wherein the edge determination unit is configured to calculate a total number of the pixels in the unit of processing that include the predetermined edge, and
the sub-pixel value storage unit is configured to increase N, with an increase in the total number of the pixels calculated by the edge determination unit, in exchange for decreasing a total number of bits in each pixel value to be stored in at least one of the representative pixel value storage area or the sub-pixel value storage area, N indicating a total number of pixels that the sub-pixel value storage area is able to store.

4. The image processing device according to claim 1 , further comprising
a pixel selection unit configured to select N pixels from among the pixels determined to include the predetermined edge, when the edge determination unit has determined that more than N pixels include the predetermined edge,
wherein for each of one or more pixels that are not selected as the N pixels by the pixel selection unit from among the more than N pixels, the representative pixel value storage unit is configured to generate the representative sub-pixel by mixing pixel values of the plural sub-pixels, and store a pixel value of the generated representative sub-pixel into the representative pixel value storage area, and
for each of the N pixels selected by the pixel selection unit, the sub-pixel value storage unit is configured to store the pixel value of each sub-pixel other than the representative sub-pixel of the pixel into the sub-pixel value storage area.

5. The image processing device according to claim 4 ,
wherein the pixel selection unit is configured to calculate, for each of the pixels determined by the edge determination unit to include the predetermined edge, a greatest color difference between the sub-pixels included in the pixel, and select N pixels in descending order of the calculated greatest color difference.

6. The image processing device according to claim 4 ,
wherein the pixel value of each of the sub-pixels includes a color value indicating a color of a pixel which includes the sub-pixel, and a depth value indicating a position of the sub-pixel in a depth direction, and
the pixel selection unit is configured to select N pixels from among the pixels determined by the edge determination unit to include the predetermined edge, in descending order of a greatest difference in the depth value between the sub-pixels.

7. The image processing device according to claim 4 ,
wherein the pixel value of each of the sub-pixels includes a color value indicating a color of a pixel which includes the sub-pixel, and a depth value indicating a position of the sub-pixel in a depth direction,
the pixel selection unit is configured to, for each of the pixels determined by the edge determination unit to include the predetermined edge, calculate a greatest color difference between the sub-pixels included in the pixel, select N pixels in descending order of the calculated greatest color difference, and select N pixels from among the pixels determined by the edge determination unit to include the predetermined edge, in descending order of a greatest difference in the depth value between the sub-pixels, and
the sub-pixel value storage unit is configured to store, into different areas of the sub-pixel value storage area, a color value of each sub-pixel other than the representative sub-pixel of each of the N pixels selected by the pixel selection unit in descending order of the greatest color difference, and a depth value of each sub-pixel other than the representative sub-pixel of each of the N pixels selected by the pixel selection unit in descending order of the greatest difference in the depth value.

8. The image processing device according to claim 4 ,
wherein each of pixels included in the image data is associated with a combination completed bit set to one of a first value and a second value, the first value indicating that the representative sub-pixel has been generated by mixing pixel values of plural sub-pixels included in the pixel, the second value indicating that pixel values of plural sub-pixels included in the pixel are not yet mixed, and
the pixel selection unit is configured to select N pixels from among pixels determined by the edge determination unit to include the predetermined edge and associated with the combination completed bit set to the second value.

9. The image processing device according to claim 8 , further comprising:
a first memory which stores, as image data, the pixel values of the sub-pixels obtained by dividing each of the pixels included in the image; and
an image processing unit configured to perform image processing on the image data stored in the first memory,
wherein for each of the sub-pixels, the first memory further stores a write-enable bit set to one of a third value and a fourth value, the third value indicating that the sub-pixel is used to render a polygon in immediately preceding rendering processing by the image processing unit, the fourth value indicating that the sub-pixel is not used to render a polygon in the immediately preceding rendering processing by the image processing unit, and
for each of the pixels determined by the edge determination unit to include the predetermined edge and associated with the combination completed bit set to the second value, the representative pixel value storage unit is configured to select a sub-pixel associated with th

Assignees

• Yuda Masato
• Ootani Naoki
• Panasonic Ip Man Co Ltd

Inventors

• Yuda Masato
• Ootani Naoki

Classifications

• G06T11/23

  using straight lines or curves · CPC title

• G06T1/60 Primary

  Memory management · CPC title

• G06T2200/12

  involving antialiasing · CPC title

• G06T15/503

  Blending, e.g. for anti-aliasing · CPC title

• G06T5/002

  Physics · mapped topic