Abstract: Instead of using a single LUT to model a processing function, it is proposed to use another smaller LUT, i.e. an iterative LUT, such that, when applied at least two times in succession to data to process, the same processing function is modeled with at least the same accuracy. A specific way to compute this iterative LUT is given. Specific applications are given in the field of color processing. Modeling is more accurate and/or less bins are needed to model complex functions.

Abstract: A method for generating a fourth color transform is disclosed, wherein said fourth color transform transforms an original picture into a target color graded version of said original picture.

Abstract: The present invention relates to a method for estimating cast shadow regions and highlight regions in a scene, said scene being represented by a low dynamic range image, called LDR image, and a high dynamic range, called HDR image, said method comprising the steps of: —computing (S1) a detail map, called LDR detail map, of the LDR image, said LDR detail map associating a detail level to each pixel of the LDR image, —computing (S2) a detail map, called HDR detail map, of the HDR image, said HDR detail map associating a detail level to each pixel of the HDR image, and —Computing a detecting (S3) regions of the scene where the detail level in the HDR detail map is greater than the detail level in the LDR detail map, said detected regions corresponding to cast shadow regions or highlights region of the scene.

Abstract: According to this method, upon reception of a color transform associated with a main sequence, a transition sequence is generated from successive images of this main sequence such that the first image of this transition sequence is an image received after reception of this color transform, transition color transforms associated with images of said transition sequence are generated by blending a color transform associated with a previous main sequence or no color transform with the second color transform, and each image of this transition sequence is processed using the transition color transform associated with said image.

Abstract: Method wherein each image of the content is transformed using at least one pre-transformed image which is associated with a key image of this content wherein, from each key image and an associated pre-transformed image, a color transform is derived, and wherein each color transform is applied to a selection of images of this content which is associated with said key image. Applied to a content broadcast system comprising a server and a receiver to which are connected several types of display devices, the invention advantageously makes it possible to adapt the content to these different types.

Abstract: Said method comprises a first cusp-oriented lightness-mapping step and a second lightness-mapping step in which a source color (N) is mapped into a mapped color (N?) having the same hue (H?=H) and the same chroma (C?=C) as the source color, where the second mapping step is defined such as to bring more colors in a target color gamut and more colors closer to the boundary of this target gamut.

Abstract: An aspect of present principles is directed to methods and systems for gamut mapping source colors into target colors from a source color gamut towards a target color gamut. A difference may be determined source specific colors and corresponding target specific colors. A source hue of the source specific colors is adaptively changed towards a target hue of the corresponding target specific colors based on the difference to determine mapped specific colors. Color gamut mapping is performed for the source colors of the source color gamut towards the target color gamut based on the mapped specific colors. The specific colors are selected from primary colors, secondary colors, a group of primary colors and secondary colors. The difference is based on at least one selected from the group of hue, saturation and lightness of the source specific colors and the corresponding target specific colors.

Abstract: Source colors are mapped within a mapping segment starting at a preserved gamut boundary color (PC) and ending at a target gamut boundary color (IT-C) of the chromaticity plane, corresponding, in a linear 3D color space, to an intersection of the target color gamut (TCG) with a plane of constant luminance and with a mapping plane (MKO) comprising said source color (M), a black point (K) and a white point (O).

Abstract: Method comprising: first mapping, in a reference color space, said source colors from a source color gamut into a reference color gamut, resulting in intermediate colors, second mapping said intermediate colors from said reference color gamut into said target color gamut, resulting in target colors forming at least one mapped image, wherein said first mapping is defined through information representing said second mapping.

Abstract: In a situation where a capturing device is capturing a first image of a scene comprising a display device displaying a second image, a salient idea is to send both the captured first image and the second image, being displayed by the display device to a processing device, for comparatively processing the first and the second image to determine a characteristic associated with the display device. Being able to process the first image (comprising a displayed second image) together with the original second image advantageously allows to determine various characteristics associated with the display device that altered the displayed second image within the first image, making it different from the initial second image. Characteristics associated with the display device are for example a specular reflection occurring on the display device in the scene and disturbing the capture of the scene.

Abstract: The present invention provides a method and system for determining and providing color metadata for a downlink data channel. In accordance with the present invention color metadata is determined such that gamut mapping is defined by a transmitted source gamut which enables adapted mapping that preserves saturation and contrast levels of the source for a downlink data channel. The metadata is then provided to a downlink data channel for color management.

Abstract: An aspect of present principles is directed to methods and systems for gamut mapping source colors into target colors from a source color gamut towards a target color gamut. A difference may be determined source specific colors and corresponding target specific colors. A source hue of the source specific colors is adaptively changed towards a target hue of the corresponding target specific colors based on the difference to determine mapped specific colors. Color gamut mapping is performed for the source colors of the source color gamut towards the target color gamut based on the mapped specific colors. The specific colors are selected from primary colors, secondary colors, a group of primary colors and secondary colors. The difference is based on at least one selected from the group of hue, saturation and lightness of the source specific colors and the corresponding target specific colors.

Abstract: The present invention generally relates to a method and arrangement for estimating said at least one cross-channel color mapping model from a set of tuples of corresponding colors relative to at least two images. The method is characterized in that it uses a processor for selecting at least one intermediate tuple of corresponding colors from the set of tuples of corresponding colors by using at least one channel-wise color mapping model, and for estimating the at least one cross-channel color mapping model from the at least one intermediate selected tuple of corresponding colors.

Abstract: A method and apparatus for inverse tone mapping of an LDR image with computer generated imagery components, such components being also called visual effects, are disclosed. The disclosed method includes accessing a first LDR image, the first LDR image being obtained from at least one computer generated imagery component rendered and composited into an LDR reference image or background plate; determining an HDR lighting indication responsive to information extracted from a part of the first LDR image and a respective part of a first intermediate HDR image obtained by applying a first pass inverse tone mapping to the first LDR image; obtaining a second intermediate HDR image by applying a second pass inverse tone mapping to the LDR reference image; obtaining the first HDR image from the computer generated imagery components rendered using HDR lighting indication and composited into the second intermediate HDR image.

Abstract: For the mapping in a non-linear color space of source colors belonging to a same constant-hue leaf, instead of using a lightness mapping function based only on a cusp lightness condition stating that a source cusp color of this leaf should be mapped into a corresponding target cusp color of this leaf, it is proposed to build such a function also on other source cusp color(s) and other target cusp color(s) having hues different from that of said leaf. Preferably, the hue interval in which these other colors are considered is representative of the curvature of the non-linear color space at the position of colors of this constant-hue leaf.

Abstract: The method comprises segmenting lines into regions of saturated pixels, and, for each of these saturated regions, selecting at least one color channel that is not saturated, then, for each pixel of said region, adding to the color information provided by the saturated color channel for said pixel a difference between the color information provided by the selected non-saturated color channel for said pixel and a baseline color value computed for the region of this pixel.

Abstract: An adaptive color grade interpolation method is disclosed. The method comprises interpolating from a first color graded version of a picture adapted to first viewing conditions and a second color graded version of said picture different from the first color graded version and adapted to second viewing conditions in order to obtain a third color graded version of the picture adapted to third viewing conditions wherein said interpolating is obtained from said first color graded version, a first mapped color version of said first color graded version adapted to said third viewing conditions and to a second mapped color version of said first color graded version adapted to said second viewing conditions such that said first color graded version and second mapped color version are interpolated into said first mapped color version.

Abstract: The present principles are directed to a parameterized OETF/EOTF for processing images and video. The present principles provide a method for encoding a picture, comprising: applying a parameterized transfer function to a luminance (L) signal of the picture to determine a resulting V(L) transformed signal; encoding the resulting V(L); wherein the parameterized transfer function is adjusted based on a plurality of parameters to model one of a plurality of transfer functions. The present principles also provide for a method for decoding a digital picture, the method comprising: receiving the digital picture; applying a parameterized transfer function to the digital picture to determine a luminance (L) signal of the digital picture, the parameterized transfer function being based on a plurality of parameters; wherein the parameterized transfer function is adjusted based on a plurality of parameters to model one of a plurality of transfer functions.

Abstract: A method for creating a pair of stereoscopic images is described. The method includes using at least one lightfield camera which receives respective required camera parameters for a left view and a right view. The required camera parameters define a theoretical stereo image pair to acquire respective actual camera parameters for respective sub aperture images that are generated based on the captured image by the lightfield cameras, to determine a best matching sub aperture image for the left view by comparing the required camera parameter for the left view with the actual camera parameters for the respective sub aperture images, to determine a best matching sub aperture image for right view by comparing the required camera parameter for right view with the actual camera parameters for the respective sub aperture images, and to associate the best matching sub aperture image for left view and the best matching sub aperture image for right view as a pair of stereoscopic images.

Abstract: There are provided a method and system for color correcting displays with different color gamuts. The method includes performing color correction on source picture content, using at least one of a non-reference type display having a non-reference color gamut and a reference type display having a reference color gamut. The performing step includes mastering the source picture content to provide mastered color corrected picture content for display on the reference type displays having a reference color gamut. The performing step further includes generating metadata for a subsequent inverse color gamut mapping that color transforms the mastered color corrected picture content for display on non-reference type displays having a non-reference color gamut. The subsequent inverse color gamut mapping is an inverse operation of a color gamut mapping applied during the color correction to obtain the mastered color corrected picture content for display on the reference type displays having the reference color gamut.