Layer Decomposition in Hierarchical VDR Coding

摘要

Techniques use multiple lower bit depth (e.g., 8 bits) codecs to provide higher bit depth (e.g., 12+ bits) high dynamic range images from an upstream device to a downstream device. Multiple layers comprising a base layer and one or more enhancement layers may be used to carry video signals comprising image data compressed by lower bit depth encoders to a downstream device, wherein the base layer cannot be decoded and viewed on its own. Lower bit depth input image data to base layer processing may be generated from higher bit depth high dynamic range input image data via advanced quantization to minimize the volume of image data to be carried by enhancement layer video signals. The image data in the enhancement layer video signals may comprise residual values, quantization parameters, and mapping parameters based in part on a prediction method corresponding to a specific method used in the advanced quantization. Adaptive dynamic range adaptation techniques take into consideration special transition effects, such as fade-in and fade-outs, for improved coding performance.

主权项

1. A method, comprising:
receiving an input visual dynamic range (VDR) image in a sequence of input images, wherein the input VDR image comprises a first bit depth; selecting a specific advanced quantization function from one or more available advanced quantization functions; applying the specific advanced quantization function to the input VDR image to generate an input base layer image, wherein the input base layer image comprises a second bit depth, which is lower than the first bit depth; compressing image data derived from the input base layer image into a base layer (BL) video signal; and compressing at least a portion of image data derived from the input VDR image into one or more enhancement layer (EL) video signals, wherein the advanced quantization method is selected based on one or more factors including minimizing an amount of image data to be encoded into the one or more EL video signals relative to the input VDR image.