In its latest issue (08/16), the German specialist journal “connect” presented the new nationwide fixed network test. Following the current trend that telecom networks are increasingly transforming from voice telephony to video distribution networks, an entirely new focus was placed on WebTV video quality. Here, the new video quality measurement technology “PEVQ-S” developed by the Erlangen-based company OPTICOM enables analysis of the subjective video quality as perceived by the users. For the first time, this measurement technology allows a large-scale comparison of commercial providers of video streaming subscriptions such as Netflix, Amazon Video and Videoload, as well as well-known video platforms such as Youtube, Vimeo and Facebook.
In so doing, the quality difference between these video services was especially evaluated - both with regard to the locations and the different broadband providers. Here, it again became clear that the technology (DSL, cable or fibre optics) and speed of the connection alone do not serve as an indication of the maximum achievable quality – faster does not automatically mean better.
The video performance also greatly depends on how well the operators’ networks connect to the big content delivery networks such as Akamai, Amazon AWS, Level 3 or Limelight.
In over 2.1 million individual measurements at a total of 43 German locations, the company zafaco used automated test systems to analyze video and voice quality (among other things) for four weeks using standardized measurement software from OPTICOM.
“With nearly 300,000 individual measurements for WebTV alone, zafaco provided urgently needed transparency with the largest video quality benchmark to date: while video portals seem to users just like normal websites, in reality they conceal complex logistics for ‘streaming’ and playback of the video contents, whereby so-termed ‘Content Delivery Networks’, i.e. the provider’s own or rented video server network structure, constantly adapt the bitrate to the Internet bandwidth and end device” explained Michael Keyhl, the founder and managing director of OPTICOM. “Mobile networks, for example, provide lower video quality than a fixed network to a Smart-TV. Our video quality measurement technology PEVQ-S is based on a range of internationally standardized algorithms which are able to recognize for each frame errors and deviations from the reference and accordingly rate the subjective, humanly perceived quality. Due to the reference-based approach, PEVQ-S is currently the only metrics worldwide which is able to quantify the maximum optimization potential with regard to the best possible quality available on the server simultaneously with the current quality, and that independently of context, based on the viewing situation – whether Smartphone, PC or TV.”
“With the OPTICOM measurement technology PEVQ-S we were able to carry out further analyses which enabled us to take a close look at the broadband and the WebTV providers in the test” added Christoph Sudhues, the founder and managing director of zafaco. “Thus, for example, it was apparent that Netflix changed the configuration of its video player during the test period with the effect that the stream played at a higher quality from the beginning, which, however, led to longer waiting times until the video started to play (so-termed “Initial Buffering”). As the graph shows, both the conversion effect and the resulting outcome was reflected to differing degrees in the video quality and with all the broadband providers tested. Through the cooperation with OPTICOM, for the first time worldwide we are able to test the measurable service quality of the popular video services from Amazon, Facebook, Netflix, Videoload, Vimeo and Youtube within the framework of a continuous benchmark and thus contribute to securing and optimizing the quality aspects in convergent networks. Which, in turn, results in increased customer satisfaction.”
It was not until mid-June that the German Federal Cabinet obligated the providers to ensure more transparency in Internet connections by passing the Transparency Regulation of the Federal Network Agency. As the current results show, the data transfer rate alone is, however, no guarantee for consistent and genuine high quality. In view of the enormous significance of video streaming via the Internet, the Erlangen measurement technology PEVQ-S can make a decisive contribution here by objectively and realistically characterizing the quality of video services as actually perceived by the consumer. PEVQ-S has, like the globally established POLQA voice quality measurement technology which also comes from OPTICOM, been taken under license by leading manufacturers of measuring instruments. The years of development have paid off: in the most recent independent tests within the framework of the ongoing standardisation Q14/12 in the International Telecommunications Union (ITU-T), PEVQ-S ranked among the winners with the highest measurement accuracy, clearly relegating simpler proposals, such as only analyzing bitrate and image resolution, to the back of the field.