The high brightness and dark parts of videos are compressed and lost during the transmitting by the traditional standard dynamic range (SDR). The high dynamic range (HDR) has gained more and more attention, because it can faithfully restore the high brightness and dark parts of grayscale and color level.
In order to realize the conversion and coding of HDR of videos, a PQ codec is written on the basis of H.265 in C language and the functions of pre-coding and post-decoding are added. The pre-coding process is divided into Perceptual Quantization (PQ) curve photoelectric conversion, RGB and YCbCr mutual conversion, quantification, sampling. The post-decoding process is inverse process of pre-coded, which includes upper sampling, anti-quantization, color space conversion, perceptual quantification. The core of codec is to use the PQ curve to transform the optical signal into electrical signal nonlinearly, thus expanding the dynamic reproduction range of the traditional transmission system. Finally, decoding videos can realize the whole brightness dynamic range, which is visible to the human eye.
It contains 2 different parts. First part is 8 bit image coder and decoder. Second part is 10 bit image coder and decoder. All of the 2 parts have pre-coding and post-decoding process. You can use them without H.265, but if you want to make it more correct, you should use a H.265 coder and decoder between my pre-coding and post-decoding process. It is easy to find H.265 coder and decoder on the Internet.