Method of and device for encoding an hdr video together with an ldr video, method of and device for reconstructing one of an hdr video and an ldr video coded together and pf storage medium

Device for encoding an HDR video of high dynamic range together with an LDR video, the LDR video providing a lower dynamic range depiction of the HDR video content, the device comprising processing means for

• encoding a first tone mapped version of the HDR video, called a first LDR video, and a second tone mapped version of the HDR video, called a second LDR video, extracted from the HDR video independently from the first LDR video and predictive encoding the second LDR video using the first LDR video as reference, and
• lossless encoding global illumination data further extracted from the HDR video.

Method of reconstructing an HDR video of high dynamic range, the method comprising using processing means for

• decoding an LDR video, the LDR video providing a lower dynamic range depiction of the HDR video content,
• using the LDR video and a residual for decoding a second LDR video, the second LDR video providing a further lower dynamic range depiction of the HDR video content,
• decoding global illumination data and using the global illumination data and one of the first or second LDR video for reconstructing the HDR video.

Device for reconstructing an HDR video of high dynamic range, the device comprising processing means for

• decoding an LDR video, the LDR video providing a lower dynamic range depiction of the HDR video content,
• using the LDR video and a residual for decoding a second LDR video, the second LDR video providing a further lower dynamic range depiction of the HDR video content,
• decoding global illumination data and using the global illumination data and one of the first or second LDR video for reconstructing the HDR video.