Method and apparatus for alpha blending images from different color formats

Patent metadata

Field	Value
Publication number	US-12033273-B2
Application number	US-202217972307-A
Country	US
Kind code	B2
Filing date	Oct 24, 2022
Priority date	Jun 28, 2019
Publication date	Jul 9, 2024
Grant date	Jul 9, 2024

Abstract

In some examples, an apparatus obtains source layer pixels, such as those of a content image and first destination layer pixels, such as those of a destination image. The first destination layer pixels have associated alpha values. The apparatus obtains information that indicates a first blending color format for the alpha values. The first blending color format is different from a first destination layer color format for the first destination layer pixels and an output color format for a display. The apparatus converts the source and/or first destination layer pixels to the first blending color format. The apparatus generates first alpha blended pixels based on alpha blending the source layer pixels with the first destination layer pixels using the associated alpha values. The apparatus provides, for display on the display, the first alpha blended pixels.

First claim

What is claimed is:

1. An apparatus comprising:
a graphics processing unit (GPU) comprising a display engine, wherein the display engine comprises alpha transparency optimization logic, wherein the alpha transparency optimization logic is configured to:
obtain a plurality of source layer pixels, a plurality of first alpha values, a plurality of first destination layer pixels associated with the plurality of first alpha values, and information indicating a first blending color format for the plurality of first alpha values, wherein the first blending color format is different from both a first destination layer color format associated with the plurality of first destination layer pixels and different from an output color format associated with a display; and
based on the information indicating the first blending color format for the plurality of first alpha values, convert at least one of the plurality of source layer pixels and the plurality of first destination layer pixels to the first blending color format for the plurality of first alpha values.

2. The apparatus of claim 1 wherein the alpha transparency optimization logic is further operative to:
convert at least one of the plurality of source layer pixels and the plurality of first destination layer pixels to the first blending color format;
in response to the converting the least one of the plurality of source layer pixels and the plurality of first destination layer pixels, generate a plurality of first alpha blended pixels based on alpha blending the plurality of source layer pixels with the plurality of first destination layer pixels using the plurality of first alpha values;
convert at least one of the plurality of first alpha blended pixels and a plurality of second destination layer pixels to a second blending color format; and
in response to converting the at least one of the plurality of first alpha blended pixels and the plurality of second destination layer pixels, generate a plurality of second alpha blended pixels based on alpha blending the plurality of first alpha blended pixels with the plurality of second destination layer pixels using a plurality of second alpha values; and
provide the plurality of second alpha blended pixels;
and wherein the apparatus comprises a display, wherein the display is coupled to the GPU and is configured to:
obtain, from the GPU, the plurality of second alpha blended pixels; and
display the plurality of second alpha blended pixels.

3. The apparatus of claim 2 , wherein the second blending color format comprises a second blending gamma space and a second blending set of color primaries, and
wherein the alpha transparency optimization logic is configured to convert the at least one of the plurality of second alpha blended pixels and the plurality of second destination layer pixels to the second blending color format by converting the at least one of the plurality of first alpha blended pixels and the plurality of second destination layer pixels to the second blending gamma space using data representing a gamma transfer function associated with the second blending gamma space.

4. The apparatus of claim 2 , wherein the first blending color format comprises a first blending gamma space and a first blending set of color primaries,
wherein the second blending color format comprises a second blending gamma space and a second blending set of color primaries, and
wherein the first blending gamma space is different from the second blending gamma space.

5. The apparatus of claim 2 , wherein the first blending color format comprises a first blending gamma space and a first blending set of color primaries,
wherein the second blending color format comprises a second blending gamma space and a second blending set of color primaries, and
wherein the second blending gamma space is a same gamma space as an output color format associated with the display.

6. The apparatus of claim 2 , wherein the second blending color format comprises a second blending gamma space and a second blending set of color primaries, and
wherein the alpha transparency optimization logic is configured to convert the at least one of the plurality of first alpha blended pixels and the plurality of second destination layer pixels to the second blending color format by converting the at least one of the plurality of first alpha blended pixels and the plurality of second destination layer pixels to the second blending set of color primaries using data representing one or more gamma transfer functions and one or more linear to linear transfer functions.

7. The apparatus of claim 2 , wherein the alpha transparency optimization logic is further configured to convert the plurality of second alpha blended pixels to an output color format associated with the display, and
wherein the alpha transparency optimization logic is configured to provide the plurality of second alpha blended pixels by providing, to the display, the plurality of converted second alpha blended pixels that are in the output color format.

8. A method for alpha blending images from different color formats comprising:
obtaining, by logic, a plurality of source layer pixels, a plurality of first alpha values, a plurality of first destination layer pixels associated with the plurality of first alpha values, and information indicating a first blending color format for the plurality of first alpha values, wherein the first blending color format is different from both a first destination layer color format associated with the plurality of first destination layer pixels and different from an output color format associated with a display; and
based on the information indicating the first blending color format for the plurality of first alpha values, converting, by the logic, at least one of the plurality of source layer pixels and the plurality of first destination layer pixels to the first blending color format for the plurality of first alpha values.

9. The method of claim 8 , wherein the first blending color format has a different luminance range than the first destination layer color format and different than the output color format and wherein the first blending color format comprises a first blending gamma space and a first blending set of color primaries, and
wherein converting the at least one of the plurality of source layer pixels and the plurality of first destination layer pixels to the first blending color format comprises converting the at least one of the plurality of source layer pixels and the plurality of first destination layer pixels to the first blending gamma space using data representing a transfer function associated with the first blending gamma space.

10. The method of claim 9 , wherein the first blending gamma space is a linear gamma space and the transfer function is a gamma transfer function.

11. The method of claim 8 , wherein the first blending color format comprises a first blending gamma space and a first blending set of color primaries, and
wherein converting the at least one of the plurality of source layer pixels and the plurality of first destination layer pixels comprises converting the at least one of the plurality of source layer pixels and the plurality of first destination layer pixels to the first blending set of color primaries using data representing one or more gamma transfer functions and one or more linear to linear transfer functions.

12. The method of claim 8 , wherein the first blending color format comprises a first blending gamma space and a first blending set of color primaries, and
wherein converting the at least one of the plurality of source layer pixels and the plurality of first destinatio

Assignees

• Ati Technologies Ulc

Inventors

• Glen David I J
• Lee Keith

Classifications

• G06T11/10

  Texturing; Colouring; Generation of textures or colours (retouching, inpainting or scratch removal G06T5/77) · CPC title

• G06T7/90

  Determination of colour characteristics · CPC title

• G06T2210/62

  Semi-transparency · CPC title

• G06T11/40

  Filling planar surfaces by adding surface attributes, e.g. adding colours or textures · CPC title

• G09G2320/0673

  for control of gamma adjustment, e.g. selecting another gamma curve · CPC title