HIGH DYNAMIC RANGE TONE MAPPING

Number: 20170070719
Published: 2017-03-09
Filed: 2015-11-25
Assignee: Disney Enterprises, Inc.
Inventors: SMOLIC; Aljosa Aleksej Andrej et al.
CPC: G06T5/50; G06T5/92; H04N1/4072; H04N23/741
Verdict: Low Notable software
Source: Google Patents · FreePatentsOnline

The keeper's note

High-dynamic-range tone-mapping technique — novel imaging/rendering method.

Abstract

Embodiments herein disclose a tone mapping system that generates a base layer by filtering a frame in an HDR video. The tone mapping system then generates a tone curve using a tone mapping parameter derived from the base layer—e.g., a mean or maximum luminance value. Once the tone curve parameter is identified, the system performs temporal filtering to smooth out inconsistencies between the current value of the tone curve parameter and the values of tone curve parameter of at least one previous frame in the HDR video. The tone mapping systemapplies the temporally filtered tone curve to the base layer to generate a temporally coherent layer. The temporally coherent base layer can be combined with a detail layer derived from the HDR video to generate a frame of a tone mapped video.

Background

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited aspects are attained and can be understood in detail, a more particular description of embodiments of the invention, briefly summarized above, may be had by reference to the appended drawings.

It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

FIG. 1 is a flowchart for converting HDR video into tone mapped video, according to one embodiment described herein.

FIG. 2 is a flowchart for temporally filtering tone curves, according to one embodiment described herein.

FIG. 3 is a flowchart for converting HDR video into tone mapped video, according to one embodiment described herein.

FIG. 4 illustrates a visual comparison of tone mapping techniques, according to one embodiment described herein.

FIG. 5 illustrates a block diagram of a computing system for performing tone mapping, according to one embodiment described herein.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specificrecitation.DETAILED DESCRIPTION

Temporal coherency has been a chron

Claims

1. A method, comprising: generating a base layer using a frame of a high dynamic range (HDR) video; deriving a tone curve parameter from the base layer; temporally filtering the tone curve parameter; and generating a temporally coherent base layer using a tone curve derived from the temporally filtered tone curve parameter. 9. A computer-readable storage medium comprisingcomputer-readable program code embodied therewith, the computer-readable program code executable by a processor to: generate a base layer using a frame of a high dynamic range (HDR) video; derive a tone curve parameter from the base layer; temporally filter the tone curve parameter; and generate a temporally coherent base layer using a tone curve derived from the temporally filtered tone curve parameter. 15. A tone mapping system, comprising: a computer processor; and one or more memories containing a program which, when executed on the computer processor, performs an operation comprising: generating a base layer using a frame of a high dynamic range (HDR) video; deriving a tone curve parameter from the base layer; temporally filtering the tone curve parameter; and generating a temporally coherent base layer using a tone curve derived from the temporally filtered tone curve parameter.