A method and an apparatus for generating data representative of a pixel beam

A method for rendering a light-field content comprising:

• computing a rotation angle φ of a first straight line describing a surface of a hyperboloid of one sheet representing a volume in an object space of an optical acquisition system occupied by a set of rays of light that at least one pixel of a sensor of said optical acquisition system can sense through a pupil of said optical acquisition system, said volume being called a pixel beam, called first generating ray, around a second straight line being a revolution axis of the hyperboloid, said rotation of angle φ transforming the first generating ray into a second generating, using:
• parameters representative of an orientation of the first generating ray relatively to the revolution axis of the hyperboloid comprising an angle φ0 between a vector {right arrow over (MCMG0)}, where MC belongs to the revolution axis of the hyperboloid and MG0 belongs to the first generating ray, and an axis of a coordinate system in which the rotation angle φ is computed, and a distance between an origin of the coordinate system and a plane comprising MC and MG0,
• parameters representative of the second generating ray, and
• parameters representative of the revolution axis of the hyperboloid,
• computing the pixel beam using parameters representative of the revolution axis of the hyperboloid and parameters representative of the second generating ray and a value of a parameter representative of the pixel beam based on the value of the rotation angle φ,
• rendering said light-field content.

A device for rendering a light-field content, comprising a processor configured to:

• compute a rotation angle φ of a first straight line describing a surface of a hyperboloid of one sheet representing a volume in an object space of an optical acquisition system occupied by a set of rays of light that at least one pixel of a sensor of said optical acquisition system can sense through a pupil of said optical acquisition system, said volume being called a pixel beam, called first generating ray, around a second straight line being a revolution axis of the hyperboloid, said rotation of angle φ transforming the first generating ray into a second generating, using:
• parameters representative of an orientation of the first generating ray relatively to the revolution axis of the hyperboloid comprising an angle ω0 between a vector {right arrow over (MCMG0)}, where MC belongs to the revolution axis of the hyperboloid and MG0 belongs to the first generating ray, and an axis of a coordinate system in which the rotation angle φ is computed, and a distance between an origin of the coordinate system and a plane comprising MC and MG0,
• parameters representative of the second generating ray, and
• parameters representative of the revolution axis of the hyperboloid,
• compute the pixel beam using parameters representative of the revolution axis of the hyperboloid and parameters representative of the second generating ray and a value of a parameter representative of the pixel beam based on the value of the rotation angle φ,
• said device further comprising a display for rendering said light-field content.