SHVC, the scalable form of HEVC, codes video data of different qualities into layers, and allows subsets of the layers of video data to be extracted and used on their own. Verification tests of SHVC have been conducted to evaluate the amount of savings that can be achieved by SHVC compared to HEVC simulcast, where video data of different qualities are separately coded into independent bitstreams using HEVC. Following an initial set of SHVC verification tests that were the subject of a previous report in February 2016 (see JCTVC-W1004), this document reports the results for supplemental verification testing of SHVC compression performance to test an additional use case.
A subjective evaluation was conducted to compare the SHVC Scalable Main 10 profile to HEVC simulcast using the HEVC Main 10 profile, respectively, based on the compression performance of reference software developed as part of the SHVC development process. The supplemental tests described in this report covered the case with a standard dynamic range (SDR) base layer (in a BT.2020 “container” representation) and a high dynamic range (HDR) enhancement layer (using the SMPTE ST 2084 “PQ” transfer characteristics with BT.2020 colour primaries), with both of these using a representation with BT.2020 colour primaries. This contrasts with the previous verification test of SHVC with an HDR enhancement layer, in which the SDR base layer had used a BT.709 “container” representation.
The tests were performed using a test methodology described in this report. The results confirmed that the tested SHM 11.0 reference software encodings using the SHVC Scalable Main 10 profile achieved the same subjective quality as the HEVC simulcast encodings using the Main 10 profile while requiring on average approximately 45% less bitrate for the case when both the SDR base layer and the HDR enhancement layer are coded using the BT.2020 colour primaries (with BT.2020 transfer characteristics in the base layer and SMPTE ST 2084 “PQ” transfer characteristics in the enhancement layer).