Dynamic range converter with reconfigurable architecture and methods for use therewith

Patent metadata

Field	Value
Publication number	US-2016205368-A1
Application number	US-201514867205-A
Country	US
Kind code	A1
Filing date	Sep 28, 2015
Priority date	Jan 9, 2015
Publication date	Jul 14, 2016
Grant date	—

Abstract

In various embodiments, a dynamic range converter includes a plurality of circuits, including at least one configurable circuit that operates based on configuration data. The plurality of circuits include a first color space converter to convert a source color space of a source video having a source dynamic range to nonlinear color space signals. A linearizer configured converts the nonlinear color space signals to linearized color space signals having a mastering dynamic range via a piecewise linear interpolation of a transfer function. A color volume transformer applies dynamic color transform metadata associated with the source video to generate master adjusted color space signals from the linearized color space signals. A delinearizer converts the master adjusted color space signals to nonlinearized color space signals via a piecewise linear interpolation of an inverse transfer function in accordance with a display dynamic range. A second color space converter converts the nonlinearized color space signals to display domain signals. Other embodiments are disclosed.

First claim

What is claimed is:

1 . A dynamic range converter comprising:
a plurality of circuits, including at least one configurable circuit that operates based on configuration data, wherein the plurality of circuits include:
a first color space converter configured to convert a source color space of a source video having a source dynamic range to nonlinear color space signals;
a linearizer configured to convert the nonlinear color space signals to linearized color space signals having a mastering dynamic range via a piecewise linear interpolation of a transfer function;
a color volume transformer configured to apply dynamic color transform metadata associated with the source video to generate master adjusted color space signals from the linearized color space signals;
a delinearizer configured to convert the master adjusted color space signals to nonlinearized color space signals via a piecewise linear interpolation of an inverse transfer function in accordance with a display dynamic range; and
a second color space converter configured to convert the nonlinearized color space signals to display domain signals.

2 . The dynamic range converter of claim 1 wherein the configuration data indicates the source dynamic range, the master dynamic range and the display dynamic range.

3 . The dynamic range converter of claim 1 wherein the transfer function is configured based the configuration data as one of: a electro-optical transfer function or a gamma function and the inverse transfer function is configured based the configuration data as a corresponding one of: an inverse of the electro-optical transfer function or an inverse of the gamma function.

4 . The dynamic range converter of claim 1 wherein the plurality of circuits further comprise:
a compositer, configurable based on the configuration data, to layer the master adjusted color space signals with one or more further data planes indicated by the configuration data, prior to delinearization by the delinearizer.

5 . The dynamic range converter of claim 1 wherein the plurality of circuits further comprise:
a third color space converter, configurable based on the configuration data, to color convert the master adjusted color space signals prior to delinearization by the delinearizer.

6 . The dynamic range converter of claim 1 wherein the color volume transformer applies luminance tone mapping and chrominance tone mapping in accordance with a color component space indicated by the configuration data.

7 . The dynamic range converter of claim 1 wherein the color volume transformer applies gamut shaping, color remapping and additional color space conversion in accordance with a color component space indicated by the configuration data.

8 . The dynamic range converter of claim 7 wherein the color component space sets an input color component set for at least one of: the gamut shaping, the color remapping or the additional color space conversion, based on the color component space indicated by the configuration data.

9 . The dynamic range converter of claim 7 wherein the color component space sets an output color component set for at least one of: the gamut shaping, the color remapping or the additional color space conversion, based on the color component space indicated by the configuration data.

10 . The dynamic range converter of claim 1 wherein the color volume transformer applies luminance tone mapping and chrominance tone mapping based on a plurality of lookup tables that are separately programmable based on the configuration data.

11 . The dynamic range converter of claim 10 wherein the plurality of lookup tables are configured based on the configuration data to one of: a translation mode that directly outputs a first value from an input, or a scale mode that retrieves a second value from the input and outputs a scaled value based on multiplication of the input by the second value.

12 . The dynamic range converter of claim 1 wherein the plurality of circuits further comprise at least one of:
a dithering limiter, configurable based on the configuration data, to reduce a number of bits in display domain signals to generate video display data; or
a display encoder, configurable based on the configuration data, to generate encoded video display data, based on the display domain signals.

13 . A method comprising:
configuring at least one configurable circuit based on configuration data, to perform the following:
converting a source color space of a source video having a source dynamic range to nonlinear color space signals;
converting the nonlinear color space signals to linearized color space signals having a mastering dynamic range via a piecewise linear interpolation of a transfer function;
color volume transforming the linearized color space signals based on dynamic color transform metadata associated with the source video to generate master adjusted color space signals;
delinearizing the master adjusted color space signals to nonlinearized color space signals via a piecewise linear interpolation of an inverse transfer function in accordance with a display dynamic range; and
converting the nonlinearized color space signals to display domain signals.

14 . The method of claim 13 , wherein the configuration data indicates the source dynamic range, the master dynamic range and the display dynamic range.

15 . The method of claim 13 , wherein the transfer function is configured based the configuration data as one of: a electro-optical transfer function or a gamma function and the inverse transfer function is configured based the configuration data as a corresponding one of: an inverse of the electro-optical transfer function or an inverse of the gamma function.

16 . The method of claim 13 , wherein the color volume transforming applies luminance tone mapping and chrominance tone mapping in accordance with a color component space indicated by the configuration data.

17 . The method of claim 13 , wherein the color volume transforming applies gamut shaping, color remapping and additional color space conversion in accordance with a color component space indicated by the configuration data.

Assignees

• Vixs Systems Inc

Inventors

• Wallace Bradley Arthur
• Wu Xiaowen
• Feng Jie
• Li Xinghai

Classifications

• H04N9/64 Primary

  Circuits for processing colour signals (H04N9/77 takes precedence; camera processing pipelines for processing colour signals H04N23/84) · CPC title

• G06T2207/20208

  High dynamic range [HDR] image processing · CPC title

• G06T2207/10016

  Video; Image sequence · CPC title

• G06T5/92

  based on global image properties · CPC title

• G06T5/90

  Dynamic range modification of images or parts thereof · CPC title