SYSTEM FOR CODING HIGH DYNAMIC RANGE AND WIDE COLOR GAMUT SEQUENCES

摘要

A method of encoding a digital video data applies adaptive pre-processing to data representing high dynamic range (HDR) and/or wide color gamut (WCG) image data prior to encoding and complementary post-processing to the data after decoding in order to allow at least partial reproduction of the HDR and/or WCG data. The example methods apply one or more color space conversions, and a perceptual transfer functions to the data prior to quantization. The example methods apply inverse perceptual transfer functions and inverse color space conversions after decoding to recover the HDR and/or WCG data. The transfer functions are adaptive so that different transfer functions may be applied to video data sets including different groups of frames, frames or processing windows in a single frame. Information on the data set and information on the applied transfer function is passed as metadata from the encoder to the decoder.

主权项

1. A method of encoding a digital video, comprising:
receiving a digital video data set including at least one of high dynamic range (HDR) and wide color gamut (WCG) video data; identifying a characteristic of a portion of the digital video data set; modifying a perceptual transfer function according to the identified characteristic; applying the modified perceptual transfer function to the portion of the digital video data set to generate a perceptually modified portion of the digital video data set; applying a perceptual normalization including at least one of a gain factor or an offset to the perceptually modified digital video data set to generate a perceptually normalized portion of the digital video data set; encoding the perceptually normalized portion of the video data set to generate a bit stream; transmitting, to a decoder, the bit stream and metadata that indicates the modification of the perceptual transfer function, that identifies the perceptual normalization, and that identifies the portion of the video data set.