Mobile video usage is up across the globe and – since the U.S. tends to lag behind mobile trends – this explosive international growth likely presages significant expansion in the U.S. market. As a result, North American mobile network operators (MNOs) are looking to mobile video as a long term, money-making machine: more services, more viewers, more dollars.
|Dey: You don’t have to wait for 4G to offer mobile TV and make it commercially successful.
To address these opportunities, many operators have focused their attention on building the next generation of high-speed networks. This emphasis on 3G, WiMAX, etc., has led many market stakeholders to believe that 2G and 2.5G operators will soon be out of the race when it comes to delivering mobile video. Conversely, many in the industry have come to believe that network upgrades are the essential silver bullet for delivering compelling mobile video offerings.
Unfortunately, the industry is in for a rude shock, as this couldn’t be farther from the truth. While 3G/4G will indeed provide the “pipes” necessary to bring additional mobile services and new capabilities to subscribers, this new infrastructure in and of itself won’t suddenly fix video quality issues. In fact, real-world 3G and 4G network implementations have proved that even high speed wireless networks fluctuate – and in fact fluctuate more highly – continuing to cause viewing issues for subscribers.
The problem is the traditional belief that subscriber density, wireless bandwidth and video quality are all related in a static equation: In order to serve more subscribers, you need to either increase bandwidth or decrease video quality per user. Decreasing video quality threatens user adoption. Yet adding bandwidth is slow and costly, threatening the bottom-line. Although adding bandwidth can improve overall user experience for non-real-time services (i.e., mobile Web browsing), real-time services like mobile video are more sensitive to channel error conditions than available bandwidth. Clearly, neither of these approaches are the answer.
Another option is to make video delivery work without requiring an error-free channel.
Historically, operators have viewed mobile video as just another mobile data service that needs more bandwidth. This opinion is shaped by traditional mobile video streaming solutions that only consider one issue: available bandwidth per user. Other solutions, in a nod to the mobile environment, have added the ability to pre-encode bitrates based on specific handset capabilities and network type. This is analogous to adapting Internet video feeds based on whether the user is on dial-up, DSL or an office LAN.
Yet wireless networks are completely different beasts, because the bandwidth and channel error condition constantly fluctuates due to changes to user location, interference, subscriber density, distance, etc. Using the analogy above, it would be like trying to send video to a target user that is on an office LAN one second, then drops to dial-up and back to DSL.
It’s important to note that all wireless networks – even 3G and 4G – are highly variable and unpredictable in terms of noise. Noise conditions result in dropped packets and lost frames. Users coming in and out of coverage and moving between cells or base stations quickly change the conditions under which the video is delivered.
To combat these issues, it’s necessary to use a different approach, one that looks at multiple variables within a video stream – including initial latency, frame quality, stalling, re-buffering and audio – to determine the best way to manage perceived quality within the available spectrum.
By adopting an active feedback-based encoding approach, operators can adjust the streaming using not only various bitrates, but also different preferred combinations of streaming variables and error resiliency techniques. Based on real-world fluctuations, the mobile video optimizer can automatically select the streaming profile that is both best suited to the available bandwidth, and also incorporates sufficient resilience to override the possible loss scenarios in the subsequent adaptation interval.
Because network bandwidth and signal/noise in the mobile stream is unpredictable, the encoder must use all of the various perceptual resilience tools. The result is maintenance of a reasonable quality of experienced (QoE) in a broad range of network bandwidth and RF noise conditions.
Improving the perceived quality of mobile video is critical to its commercial success. Yet the key is not the underlying network per se (video in 3G can still fail), but rather the techniques and technology necessary to optimize each subscriber experience.
This approach allows operators to offer high quality entertainment services, like mobile TV, on existing 2G/2.5G networks, while owners of next-generation networks can offer more consistent service and gain benefits in terms of expanded coverage and increased subscriber density.
In short, operators that better control the quality and efficiency of their subscriber connections will be in the best position to profit from mobile video – regardless of network infrastructure or investments aimed at reducing channel error.
Do you agree with this opinion? What factors do you think will be required to make mobile video a commercial success? Let us know by using the comment section below.
Dey is founder and chief technology officer of Ortiva Wireless.