At the ITU-T SG12 meeting held in Geneva Switzerland, Huawei's H.265 BTV Quality Assessment Model U-vMOS gained approval by ITU-T SG12 Q13 and will be viewed as the basis for H.265 quality assessment model development.
The H.265 coding model is the quality assessment model used in BTV scenarios and forms part of Huawei's video experience assessment system, U-vMOS. The U-vMOS guidelines that Huawei submitted at the meeting fundamentally determine the application conditions and algorithm framework of this model, paving the way for incorporating Huawei's U-vMOS algorithm into communication standards.
Since Huawei proposed the importance of video experience as well as the necessity of defining experience assessment standards at ITU-T in September 2015, Huawei has actively promoted the implementation of U-vMOS standards in ITU-T and received support from the meeting participants and tier-1 carriers. Huawei has submitted a batch of documents focusing on video viewing scenarios, transmission network, H.265 and H.264 coding formats, and headend provisioning, with an aim to build end-to-end best video experience.
Apart from the in-depth research on the standard domain, Huawei is also working towards practices. Huawei released Service Flow-based U-vMOS Demo in December 2015, which is the industry's first quality assessment model that supports 4K video experience assessment and takes a lead in assessing videos with high bit rate and high definition. Through a series of standard research and practices, Huawei continues to provide the optimal network bearer for 4K service provisioning and boost the wide application of the 4K industry.
The H.265-based 4K video experience has garnered much attention in the industry, while a video quality assessment standard has been needed for a long time. G.OM_HEVC fills the niche to become the industry's first H.265-based non-reference video quality assessment model. The research guidelines and requirement specifications put forward by Huawei have been well acclaimed by ITU-T members such as DT and NTT. The cooperation between Huawei and industry partners is sure to fuel the standard definition and eventually guide the 4K industry development.
Huawei's experts participating in the ITU-T meeting
Overview of Huawei's U-vMOS
U-vMOS is the video experience standard established by Huawei from the perspective of network optimization. Experience is a user's subjective view and therefore should not be used as a determinant when it comes to assessment. Only collective views count. Huawei developed video-specific human factors engineering experiments and used devices such as eye trackers and polygraphs to track human responses to videos, with an aim to objectively record users' responses to the changing video experience. By monitoring each user's physiological reaction to video effects, U-vMOS can obtain users' varying experience between videos. The information collected from the test instruments and that contained in test reports help to establish a mathematical model and the U-vMOS scoring standard. The purpose is to obtain users' subjective video experience in objective ways.
U-vMOS includes three types of indicators: video quality, interactive experience, and viewing experience. These indicators cover various aspects, such as the definition of video program sources, program source quantity, playback screen size, operating experience, and playback fluency. The U-vMOS is expressed as a single number in the range of 1 to 5, where 1 indicates unsatisfactory, 2 fair, 3 average, 4 good, and 5 excellent. A larger screen size indicates a higher definition, a higher score, and a viewing experience that is more fluent.
U-vMOS = f(sQuality, sInteraction, sView)
The U-vMOS standard comes in two parts: user-oriented video experience and bearer network construction for video services corresponding to scores. The U-vMOS standard integrates user experience with carrier network quality, which fuels the development of the video industry chain.