Abstract: Encoding/decoding data representative of a 3D representation of a scene according to a range of points of view can involve generating a depth map associated with a part of the 3D representation according to a parameter representative of a two-dimensional parameterization associated with the part and data associated with a point included in the part, wherein the two-dimensional parameterization can be responsive to geometric information associated with the point and to pose information associated with the range of points of view. A texture map associated with the part can be generated according to the parameter and data associated with the point. First information representative of point density of points in a part of the part can be obtained. The depth map, texture map, parameter, and first information can be included in respective syntax elements of a bitstream.

Abstract: The present disclosure relates to methods, apparatus or systems for determining an aiming direction (22) of a remote motorized camera (10). The immersive video content captured by the camera (10) is associated with reference directions (13). Parameters of a discrepancy function (32, 42, 53) are calculated. This function is used to control the aiming direction (22) of the camera. It introduces a discrepancy between the rotation wanted by the user (21) and the rotation of the camera (22). An example purpose of the present disclosure is to encourage a user to rotate the camera toward reference directions, preventing him/her to rotate the camera toward the opposite direction. The present principles have the advantage to create pseudo-haptic effects, inciting the user to look toward a reference direction without making him/her sick.

Abstract: Methods and devices are provided to encode and decode a data stream carrying data representative of a three-dimensional scene, the data stream comprising color pictures packed in a color image; depth pictures packed in a depth image; and a set of patch data items comprising de-projection data; data for retrieving a color picture in the color image and geometry data. Two types of geometry data are possible. The first type of data describes how to retrieve a depth picture in the depth image. The second type of data comprises an identifier of a 3D mesh. Vertex coordinates and faces of this mesh are used to retrieve the location of points in the de-projected scene.

Abstract: A sequence of point clouds is encoded as a video by an encoder and transmitted to a decoder which retrieves the sequence of point clouds. Visible points of a point cloud are iteratively projected on a projection map to determine a patch data item list. Image patches are generated and packed into a picture. Pictures and associated patch data item list are encoded in a stream. The decoding method decodes pictures and associated patch data item lists. Pixels of image patches comprised in pictures are un-projected according to data stored in associated patches. The methods have the advantage of encoding every point of point clouds in a manner avoiding artifacts and allowing decoding at video frame rate.

Abstract: The present disclosure relates to a method for generating an image, including obtaining a source image, at least one pixel of the source image being a useful pixel and at least one distinct pixel of the source image being a non-useful pixel; and a key information indicating whether each pixel of the source image is a useful pixel or a non-useful pixel; applying a feathering processing on at least one pixel of the source image, called a border pixel, a border pixel being a non-useful pixel having at least one first useful neighbor pixel and at least one second non-useful distinct neighbor pixel, the feathering processing generating a modified image presenting a smooth transition between values of the first neighbor pixel and values of the second neighbor pixel.

Abstract: A sequence of three-dimension scenes is encoded as a video by an encoder and transmitted to a decoder which retrieves the sequence of 3D scenes. Points of a 3D scene visible from a determined point of view are encoded as a color image in a first track of the stream in order to be decodable independently from other tracks of the stream. The color image is compatible with a three degrees of freedom rendering. Depth information and depth and color of residual points of the scene are encoded in separate tracks of the stream and are decoded only in case the decoder is configured to decode the scene for a volumetric rendering.

Abstract: Method and device for generating a stream of data representative of a 3D point cloud. The 3D point cloud is partitioned into a plurality of 3D elementary parts. A set of two-dimensional 2D parametrizations is determined, each 2D parametrization representing one 3D part of the point cloud with a set of parameters. Each 3D part is represented as a 2D pixel image. A depth map and a color map are determined as a first patch atlas and a second patch atlas. A data stream is generated by combining and/or coding the parameters of the 2D parametrization, the first patch atlas, the second patch atlas and mapping information that links each 2D parametrization with its associated depth map and color map in respectively the first and second patch atlas.

Abstract: The present disclosure relates to method for embedding key information in an image, the method comprising reserving a range of DMZ values, in a predetermined range of 2N values used for storing useful data in the image, the reserved range being used for storing a key information associated with at least one coordinates in the image, with N>0 and DMZ<<2N.

Abstract: Method and device for generating a stream from image(s) of an object, comprising: obtaining data associated with points of a point cloud representing at least a part of the object; obtaining a parametric surface according to at least a geometric characteristic associated with the at least a part of the object and pose information of an acquisition device used to acquire the at least one image; obtaining a height map and one or more texture maps associated with the parametric surface; generating the stream by combining together a first syntax element relative to the at least a parameter, a second syntax element relative to the height map, a third syntax element relative to the at least one texture map and a fourth syntax element relative to a position of the acquisition device. The disclosure relates further to a method and device for rendering an image of the object from the stream thus obtained.

Abstract: A method for processing a first part of an immersive video content, for example the part to be displayed, on a client device. As to incite a user to look toward a reference part in the immersive video content, the method comprises determining a distance between the first part or subparts of the first part and at least a reference part, and processing a visually degraded version of the first part or its subparts, the greater the distance, the higher the level of the visual degradation.

Abstract: The present disclosure relates to methods, apparatus or systems for formatting of backward compatible immersive video streams. At least one legacy rectangular video is captured from an immersive video obtained from a source (82). A set of camera control data are used to determine which parts of the immersive video will constitute legacy videos (84). These part are removed from the immersive video (83) and every prepared videos are packaged in a stream (85). The structure from the stream is a container. Information data about the location and size of removed parts may be added in the stream.

Abstract: The present disclosure relates to methods, apparatus or systems for calculating a 3D density map (33) for a 3D scene (32) in which significant objects have been annotated and associated with a significance weight. The 3D density map is computed in function of the location of the significant objects and the location of at least one virtual camera in the 3D scene. The space of the 3D scene is split in regions and a density is computed for each regions according to the significant weights. The 3D density map is transmitted to an external module configured to reorganize the scene according to the 3D density map.

Abstract: The present disclosure relates to methods, devices or streams for encoding, transmitting and decoding two-dimension point clouds. When encoding point clouds as frames, a large number of pixels are not used. A dense mapping operator optimizes the use of pixels but requires a lot of data to be encoded in the stream and its inverse operator is difficult to compute. A simplified mapping operator is generated according to a dense mapping operator and is stored as matrices of two-dimension coordinates representative of an unfolded grid which requires low space in the stream. The inverse operator is easy to generate according to the unfolded grid.

Abstract: A method and device for determining a first information representative of a point of interest of a large field-of-view content. To reach that aim, a second information representative of at least a viewing direction associated with at least a part of the large field-of-view content is obtained, a third information representative of an interest in the large field-of-view content is obtained, and the first information is determined from the second information and the third information.

Abstract: A configuration method of a first access point of a network is disclosed, which comprises a configuration of the first access point as belonging to a low power set and able to transmit at a power level lower than a first value on at least one low power channel; a transmission of an indication that the first access point belongs to the low power set and a selection of a low power channel for transmission among at least one low power channel on which the reception power of a signal transmitted by the neighboring access points is less than a second power level.

Abstract: Method and device for generating a stream from image(s) of an object is disclosed. The method includes the steps of obtaining data associated with points of a point cloud representing at least a part of the object, obtaining a parametric surface according to at least a geometric characteristic associated with the at least a part of the object and pose information of an acquisition device used to acquire the at least one image, obtaining a height map and one or more texture maps associated with the parametric surface, and generating the stream by combining together a first syntax element relative to the at least a parameter, a second syntax element relative to the height map, a third syntax element relative to the at least one texture map and a fourth syntax element relative to a position of the acquisition device. The disclosure relates further to a method and device for rendering an image of the object from the stream thus obtained.

Abstract: The invention relates to method for configuring a first wireless network that includes at least one access point. In order to optimize the configuration of the first wireless network, the method comprises a step of configuring at least one parameter of the at least one access point of the first wireless network on the basis of at least a portion of the linking balance of a second wireless network including at least two nodes, the nodes being positioned in a predetermined physical space.

Abstract: The present disclosure generally relates to a gaze tracking device. Gaze tracking is a process of measuring either the point of regard or the motion of an eye relatively to the head of a person. A gaze tracking device is a device capable of measuring eye positions and eye movement. In order to track the gaze of a person, infra-red light is projected into the user's eye. Utilizing the primary Purkinje reflection and the pupil-masked reflection, the position of the eye of the user is determined. The gaze tracking devices running such a tracking method offer a limited field of view due to the illumination scheme combined with the geometry of the reflected images. It is proposed a gaze tracking device embedding a light-field camera. Such a gaze tracking device may be embedded in a head mounted device.

Abstract: A method for processing a first part of an immersive video content, for example the part to be displayed, on a client device. As to incite a user to look toward a reference part in the immersive video content, the method comprises determining a distance between the first part or subparts of the first part and at least a reference part, and processing a visually degraded version of the first part or its subparts, the greater the distance, the higher the level of the visual degradation.

Abstract: The present invention concerns a method and a device for transmitting data between a sender, and at least two receivers, in a network where a data between a sender and a receiver is carried on a connection and where a unicast connection enables a sender to send the data and a receiver to acknowledge a reception of the data. The method comprises the steps of opening a unique unicast connection identified with a connection identifier; and indicating the connection identifier to the sender and the receivers, so that the sender sends the data on the unicast connection, and the receivers receive the data on the unicast connection.