Abstract: Two corresponding color patches are displayed on two image displays until adjusted by a viewer to match visually to a common color. Two sets of code values rendered on the two corresponding color patches on the two image displays are identified. Two sets of tristimulus values for the viewer are determined based on the two sets of code values rendered on the two corresponding color patches on the two image displays. The viewer's color matching function are generated based on the two sets of tristimulus values. The viewer's CMF is used in image rendering operations on a target image display.

Abstract: Systems and methods for adjusting video processing curves are disclosed herein. In one embodiment a method for applying an adjustment to an original curve derived from a set of input image data is disclosed, comprising: receiving a set of input image data to be adjusted; calculating an original curve from the set of input image data; receiving an adjustment curve, the adjustment curve based upon a desired image parameter; and applying the adjustment curve to the original curve to produce a resulting curve. In another embodiment, a display management unit (DMU) comprising a processor is disclosed that, upon receiving a set of input image data, processes the original curve according to: calculating an original curve from the set of input image data; receiving an adjustment curve, the adjustment curve based upon a desired image parameter; and applying the adjustment curve to the original curve to produce a resulting curve.

Abstract: Methods and systems for mapping images from a first dynamic range to a second dynamic on a target display with power limitations are described. Given: an input image in a first dynamic range, input metadata (Smin, Smid, Smax), power-independent luminance characteristics of a target display (Tmin, reference Tmax), and an APL function of the target display, wherein the APL function determines output luminance in the target display as a function of average picture level (APL) input in the target display, a processor generates an adaptive output of the maximum luminance level for the target display (Tmax) so that when mapping the image from the first dynamic range to the second dynamic range, the anchor points of the tone-mapping function are adjusted according to the APL function of the target display.

Abstract: Methods and systems for the display management of HDR video signals are presented. The mapping is based on tone mapping and color volume mapping which map an input signal with an input dynamic range and color volume to a target display with a target dynamic range and color volume. Both a global tone-mapping and precision-mapping methods using pyramid filtering are presented.

Abstract: A display apparatus, a display management module and a method for ambient light compensation are described. The display management module is configured to receive an input video signal comprising a sequence of video frames and to determine whether a current video frame of the sequence of video frames immediately follows a scene change. The display management module is further configured to adjust ambient light compensation applied to the input signal in dependence on the signal indicative of intensity of ambient light only in response to determining that the current video frame of the sequence of video frames immediately follows a scene change.

Abstract: In a method for dithering image data, a processor receives an input image in a first color space and a first bit depth larger than 8 bits. The processor converts the input image into a first image in a perceptually uniform color space, such as the BT. 2100 ICtCp color space, with pixel values scaled to be within a target bit depth, it quantizes the first image to generate a quantized image, it generates an error image between the first image and the quantized image, and using a random threshold, it generates a dithered image based on the random threshold, the error image, and the quantized image, allowing to reduce the bit-depth representation for visually consistent reproduction by two bits.

Abstract: Methods and systems for mapping images from a first dynamic range to a second dynamic on a target display with power limitations are described. Given: an input image in a first dynamic range, input metadata (Smin, Smid, Smax), power-independent luminance characteristics of a target display (Tmin, reference Tmax), and an APL function of the target display, wherein the APL function determines output luminance in the target display as a function of average picture level (APL) input in the target display, a processor generates an adaptive output of the maximum luminance level for the target display (Tmax) so that when mapping the image from the first dynamic range to the second dynamic range, the anchor points of the tone-mapping function are adjusted according to the APL function of the target display.

Abstract: Input scene images are captured from an original scene. The input scene images may be represented in an input color space. The input scene images are converted into color-space-converted scene images in one of an LMS color space, an ICtCp color space, etc. Scene light levels represented in the color-space-converted scene images are mapped, based at least in part on an optical transfer function, to mapped light levels. A tone mapping is applied to the mapped light levels to generate corresponding display light levels to be represented in display images. The display images may be rendered on a target display.

Abstract: Methods and systems are described for processing an image captured with an image sensor, such as a camera. In one embodiment, an estimated ambient light level of the captured image is determined and used to compute an optical-optical transfer function (OOTF) that is used to correct the image to preserve an apparent contrast of the image under the estimated ambient light level in a viewing environment. The estimated ambient light level is determined by scaling pixel values from the image sensor using a function that includes exposure parameters and a camera specific parameter derived from a camera calibration.

Abstract: In a method to improve backwards compatibility when decoding high-dynamic range images coded in a wide color gamut (WCG) space which may not be compatible with legacy color spaces, hue and/or saturation values of images in an image database are computed for both a legacy color space (say, YCbCr-gamma) and a preferred WCG color space (say, IPT-PQ). Based on a cost function, a reshaped color space is computed so that the distance between the hue values in the legacy color space and rotated hue values in the preferred color space is minimized HDR images are coded in the reshaped color space. Legacy devices can still decode standard dynamic range images assuming they are coded in the legacy color space, while updated devices can use color reshaping information to decode HDR images in the preferred color space at full dynamic range.

Abstract: In a method to improve backwards compatibility when decoding high-dynamic range images coded in a wide color gamut (WCG) space which may not be compatible with legacy color spaces, hue and/or saturation values of images in an image database are computed for both a legacy color space (say, YCbCr-gamma) and a preferred WCG color space (say, IPT-PQ). Based on a cost function, a reshaped color space is computed so that the distance between the hue values in the legacy color space and rotated hue values in the preferred color space is minimized. HDR images are coded in the reshaped color space. Legacy devices can still decode standard dynamic range images assuming they are coded in the legacy color space, while updated devices can use color reshaping information to decode HDR images in the preferred color space at full dynamic range.

Abstract: In a method to improve backwards compatibility when decoding high-dynamic range images coded in a wide color gamut (WCG) space which may not be compatible with legacy color spaces, hue and/or saturation values of images in an image database are computed for both a legacy color space (say, YCbCr-gamma) and a preferred WCG color space (say, IPT-PQ). Based on a cost function, a reshaped color space is computed so that the distance between the hue values in the legacy color space and rotated hue values in the preferred color space is minimized HDR images are coded in the reshaped color space. Legacy devices can still decode standard dynamic range images assuming they are coded in the legacy color space, while updated devices can use color reshaping information to decode HDR images in the preferred color space at full dynamic range.

Abstract: Methods for encoding and decoding high-dynamic range signals are presented. The signals are encoded in a high frame rate and are accompanied by frame-rate conversion metadata defining a preferred set of frame-rate down-conversion parameters, which are determined according to the maximum luminance of a target display, display playback priority modes, or judder control modes. A decoder uses the frame-rate conversion metadata to apply frame-rate down-conversion to the input high-frame-rate signal according to at least the maximum luminance of the target display and/or the characteristics of the signal itself. Frame-based and pixel-based frame-rate conversions, and judder models for judder control via metadata are also discussed.

Abstract: Methods are disclosed for ambient light-adaptive display management. Given an input image, image metadata, an ambient-light signal, and parameters characterizing a target display, a processor generates an ambient-light adjustment function which maps input luminance values in a reference viewing environment to output luminance values in a target viewing environment, wherein the target viewing environment is determined based on the ambient-light signal. The ambient-light adjustment function is applied to the input image and the input metadata to generate a virtual image and new metadata. A tone-mapping function based on the new metadata and target display parameters is applied to the virtual image to generate an output image. The parameters for the target display are computed based on the ambient-light signal, global dimming metadata, and the luminance characteristics of the target display.

Abstract: Methods for encoding and decoding high-dynamic range signals are presented. The signals are encoded in a high frame rate and are accompanied by frame-rate conversion metadata defining a preferred set of frame-rate down-conversion parameters, which are determined according to the maximum luminance of a target display, display playback priority modes, or judder control modes. A decoder uses the frame-rate conversion metadata to apply frame-rate down-conversion to the input high-frame-rate signal according to at least the maximum luminance of the target display and/or the characteristics of the signal itself. Frame-based and pixel-based frame-rate conversions, and judder models for judder control via metadata are also discussed.

Abstract: Methods for mapping an image from a first dynamic range to a second dynamic range are presented. The mapping is based on a function that includes two spline polynomials determined using three anchor points and three slopes. The first anchor N point is determined using the black point levels of the input and target output, the second anchor point is determined using the white point levels of the input and target output, and the third anchor point is determined using mid-tones information data for the input and target output. The mid-tones level of the target output is computed adaptively based on an ideal one-to-one mapping and by preserving input contrast in both the blacks and the highlights. An example tone-mapping transfer function based on third order (cubic) Hermite splines is presented.

Abstract: Downsampled video content is generated in a subsampling color space from linearized video content in the subsampling color space. The linearized video content represents a first spatial dimension, whereas the downsampled video content represents a second spatial dimension lower than the first spatial dimension. Opponent channel data is derived in a transmission color space from the downsampled video content. Output video content is generated from luminance data in the linearized video content and the opponent channel data in the transmission color space. The output video content may be decoded by a downstream recipient device to generate video content in an output color space.

Abstract: Input scene images are captured from an original scene. The input scene images may be represented in an input color space. The input scene images are converted into color-space-converted scene images in one of an LMS color space, an ICtCp color space, etc. Scene light levels represented in the color-space-converted scene images are mapped, based at least in part on an optical transfer function, to mapped light levels. A tone mapping is applied to the mapped light levels to generate corresponding display light levels to be represented in display images. The display images may be rendered on a target display.

Abstract: Methods for mapping an image from a first dynamic range to a second dynamic range are presented. The mapping is based on a function that includes two spline polynomials determined using three anchor points and three slopes. The first anchor point is determined using the black point levels of the input and target output, the second anchor point is determined using the white point levels of the input and target output, and the third anchor point is determined using mid-tones information data for the input and target output. The mid-tones level of the target output is computed adaptively based on an ideal one-to-one mapping and by preserving input contrast in both the blacks and the highlights. An example tone-mapping transfer function based on third order (cubic) Hermite splines is presented.

Abstract: In a method to improve backwards compatibility when decoding high-dynamic range images coded in a wide color gamut (WCG) space which may not be compatible with legacy color spaces, hue and/or saturation values of images in an image database are computed for both a legacy color space (say, YCbCr-gamma) and a preferred WCG color space (say, IPT-PQ). Based on a cost function, a reshaped color space is computed so that the distance between the hue values in the legacy color space and rotated hue values in the preferred color space is minimized HDR images are coded in the reshaped color space. Legacy devices can still decode standard dynamic range images assuming they are coded in the legacy color space, while updated devices can use color reshaping information to decode HDR images in the preferred color space at full dynamic range.