Abstract: To encode High Dynamic Range (HDR) images, the HDR images can be converted to Low Dynamic Range (LDR) images through tone mapping operation, and the LDR images can be encoded with an LDR encoder. The present principles formulates a rate distortion minimization problem when designing the tone mapping curve. In particular, the tone mapping curve is formulated as a function of the probability distribution function of the HDR images to be encoded and a Lagrangian multiplier that depends on encoding parameters. At the decoder, based on the parameters indicative of the tone mapping function, an inverse tone mapping function can be derived to reconstruct HDR images from decoded LDR images.

Abstract: For a picture with two or more color components, the prediction residuals for the first color component of a block to be encoded may be transformed with a first transform. The transform coefficients for the first color component may go through quantization, de-quantization and inverse transform to obtain reconstructed prediction residuals. Based on the reconstructed prediction residuals for the first color component, the phases of the transform basis function of the first transform can be adjusted to improve the sparsity of the transformed signal. The prediction residuals for the remaining color components may then be transformed with the adjusted transform. In order to determine the phase shift factor, the reconstructed prediction residuals for the first color component may be transformed with the first transform, adjusted by different candidate phase shift factors, and the candidate phase shift factor that provides a smallest sparsity measure can be selected for the block.

Abstract: A method and an apparatus for encoding a picture are disclosed. For at least one block of a picture to encode, a block predictor is determined (22) for a decoded first component (21) of said at least one block, from a reconstructed region of a first component of said picture. At least one second component of said at least one block is then encoded (23) by predicting said at least one second component from a second component of said block predictor. Corresponding decoding method and apparatus are disclosed.

Abstract: A content stream comprising video and synchronized illumination data is based on a reference lighting setup from, for example, the site of the content creation. The content stream is received at a user location where the illumination data controls user lighting that is synchronized with the video data, so that when the video data is displayed the user's lighting is in synchronization with the video. In one embodiment, the illumination data is also synchronized with events of a game, so that a user playing games in a gaming environment will have his lighting synchronized with video and events of the game. In another embodiment, the content stream is embedded on a disk.

Abstract: Methods and apparatus enable video coding and decoding related to omnidirectional video that has been packed into frames for coding or decoding. In an embodiment, the packed frames are stereo omnidirectional video images. These techniques enable different portions of the packed frames to be used for prediction of other portions, thus allowing greater coding efficiency. The portions used as reference can undergo resampling to give the reference portions a same sampling resolution as the portion being coded. In one embodiment, syntax is included comprising packing information, resampling information or other information. In another embodiment, syntax specifies horizontal resampling information, or other information related to prediction of the portions of video images.

Abstract: To encode High Dynamic Range (HDR) images, the HDR images can be converted to Low Dynamic Range (LDR) images through tone mapping operation, and the LDR images can be encoded with an LDR encoder. The present principles formulates a rate distortion minimization problem when designing the tone mapping curve. In particular, the tone mapping curve is formulated as a function of the probability distribution function of the HDR images to be encoded and a Lagrangian multiplier that depends on encoding parameters. At the decoder, based on the parameters indicative of the tone mapping function, an inverse tone mapping function can be derived to reconstruct HDR images from decoded LDR images.

Abstract: A content stream comprising video and synchronized illumination data is based on a reference lighting setup from, for example, the site of the content creation. The content stream is received at a user location where the illumination data controls user lighting that is synchronized with the video data, so that when the video data is displayed the user's lighting is in synchronization with the video. In one embodiment, the illumination data is also synchronized with events of a game, so that a user playing games in a gaming environment will have his lighting synchronized with video and events of the game. In another embodiment, the content stream is embedded on a disk.

Abstract: The present disclosure generally relates to a method for predicting at least one block of pixels of a view (170) belonging to a matrix of views (17) obtained from light-field data belong with a scene. According to present disclosure, the method is implemented by a processor and comprises for at least one pixel to predict of said block of pixels: —from said matrix of views (17), obtaining (51) at least one epipolar plane image (EPI) belong with said pixel to predict, —among a set of unidirectional prediction modes, determining (52) at least one optimal unidirectional prediction mode from a set of previous reconstructed pixels neighboring said pixel to predict in said at least one epipolar plane image, —extrapolating (53) a prediction value of said pixel to predict by using said at least one optimal unidirectional prediction mode.

Abstract: For a picture with two or more color components, the prediction residuals for the first color component of a block to be encoded may be transformed with a first transform. The transform coefficients for the first color component may go through quantization, de-quantization and inverse transform to obtain reconstructed prediction residuals. Based on the reconstructed prediction residuals for the first color component, the phases of the transform basis function of the first transform can be adjusted to improve the sparsity of the transformed signal. The prediction residuals for the remaining color components may then be transformed with the adjusted transform. In order to determine the phase shift factor, the reconstructed prediction residuals for the first color component may be transformed with the first transform, adjusted by different candidate phase shift factors, and the candidate phase shift factor that provides a smallest sparsity measure can be selected for the block.

Abstract: To encode High Dynamic Range (HDR) images, the HDR images can be converted to Low Dynamic Range (LDR) images through tone mapping operation, and the LDR images can be encoded with an LDR encoder. The present principles formulates a rate distortion minimization problem when designing the tone mapping curve. In particular, the tone mapping curve is formulated as a function of the probability distribution function of the HDR images to be encoded and a Lagrangian multiplier that depends on encoding parameters. At the decoder, based on the parameters indicative of the tone mapping function, an inverse tone mapping function can be derived to reconstruct HDR images from decoded LDR images.

Abstract: To encode High Dynamic Range (HDR) images, the HDR images can be converted to Low Dynamic Range (LDR) images through tone mapping operation, and the LDR images can be encoded with an LDR encoder. The present principles formulates a rate distortion minimization problem when designing the tone mapping curve. In particular, the tone mapping curve is formulated as a function of the probability distribution function of the HDR images to be encoded and a Lagrangian multiplier that depends on encoding parameters. At the decoder, based on the parameters indicative of the tone mapping function, an inverse tone mapping function can be derived to reconstruct HDR images from decoded LDR images.

Abstract: The present disclosure generally relates to a method for predicting at least one block of pixels of a view (170) belonging to a matrix of views (17) obtained from light-field data belong with a scene, According to present disclosure, the method is implemented by a processor and comprises for at least one pixel to predict of said block of pixels: —from said matrix of views (17), obtaining (51) at least one epipolar plane image (EPI) belong with said at least one pixel to predict, —among a set of bidirectional prediction modes, determining (52) at least one optimal bidirectional prediction mode from a set of previous reconstructed pixels neighbouring said at least one pixel to predict in said at least one epipolar plane image, —extrapolating (53) a prediction value of said at least one pixel to predict by using said at least one optimal bidirectional prediction mode.

Abstract: A method for encoding a plenoptic image divided into blocks is disclosed. The method comprises: —encoding (S120) a block in a central region of the plenoptic image, called central block, without spatial prediction; and —predictively encoding (S130) blocks immediately surrounding said central block by spatially interleaving spatial unidirectional prediction and spatial bi-directional prediction.

Abstract: Encoding or decoding a stack of images of a same scene focused at different focalization distances from one image to another can involve encoding or decoding information representing an image of the stack of images, where the image meets an image sharpness criterion, reconstructing the image into a reconstructed image, and encoding or decoding at least one other image of the stack of images by prediction from at least the reconstructed image.

Abstract: A spatial guided prediction technique uses reconstructed pixels of a first component of a digital video image block to determine prediction modes used to recursively build prediction blocks for the other components of the same digital video image block. The technique builds improved predictions resulting in smaller prediction residuals and less bits to code for a given image quality. In one embodiment, the prediction blocks for the subsequent digital video component blocks are built recursively line by line. In another embodiment, the prediction blocks for subsequent digital video component blocks are built recursively column by column.

Abstract: A method for encoding a current focal stack is disclosed that comprises a set of images focused at a different focalization distance from one image to another. According to present disclosure, the method comprises: —encoding (31) information representing an image of the current focal stack, the image being selected in said current focal stack according to an image sharpness criterion, and reconstructing the image into a reconstructed image; —encoding (32) at least another image of the current focal stack by prediction from at least the reconstructed image.

Abstract: A method and an apparatus for encoding a picture are disclosed. For at least one block of a picture to encode, a block predictor is determined (22) for a decoded first component (21) of said at least one block, from a reconstructed region of a first component of said picture. At least one second component of said at least one block is then encoded (23) by predicting said at least one second component from a second component of said block predictor. Corresponding decoding method and apparatus are disclosed.

Abstract: When performing inter-layer prediction, the present method and apparatus make predictive inter-layer determinations, such as from the LDR layer to the HDR layer, based on pixels used in the LDR layer for intra prediction of the LDR block using an intra LDR mode and also based on the homologous pixels in the HDR layer for the intermediate intra prediction block using the same intra LDR mode. By using these bases, it is possible to estimate an inverse tone mapping function and then apply this estimated function to the LDR block in order to determine the inter-layer HDR prediction block.

Abstract: A method and device for processing LDR images of a video sequence to improve image quality. The method comprises temporally decomposing successive HDR frames of a video sequence and the corresponding LDR frames and performing a comparison between the HDR and LDR frequency sub-bands. A current LDR image can then be modified on the basis of a comparison between the frequency sub-bands.

Abstract: The present disclosure generally relates to a method for predicting at least one block of pixels of a view (170) belonging to a matrix of views (17) obtained from light-field data belong with a scene. According to present disclosure, the method is implemented by a processor and comprises for at least one pixel to predict of said block of pixels: —from said matrix of views (17), obtaining (51) at least one epipolar plane image (EPI) belong with said pixel to predict, —among a set of unidirectional prediction modes, determining (52) at least one optimal unidirectional prediction mode from a set of previous reconstructed pixels neighboring said pixel to predict in said at least one epipolar plane image, —extrapolating (53) a prediction value of said pixel to predict by using said at least one optimal unidirectional prediction mode.