Netflix announced last week that select programming would be available in Ultra HD 4K format on 4K Smart TVs supporting HEVC (High-Efficiency Video Coding).
While Netflix has become one of my favorite channels—right up there with Showtime, HBO and AMC—the announcement has this fan wondering if it amounts to anything more than window dressing for marketing purposes.
Netflix’s current HD content reportedly maxes out at a bitrate of 7 Mbps, while their 4K content will reportedly use a bitrate of 15.6 Mbps. (For the record, this bitrate sounds pretty high to me, but since HEVC is still very new, it’s likely that encoding is not yet optimized, and the bitrates required initially will be significantly higher than what the codec is capable of achieving, in the future.)
At the same time, Netflix’s most recent ISP performance rankings, still show the highest-performing ISP, Google Fiber, averaging less than 4 Mbps during primetime, and all other ISPs averaging less than 3 Mbps. So it’s hard to understand how many Netflix subscribers will be able to take advantage of a service requiring bitrates more than six times the average of the top 10 ISPs on their list.
What’s more, those familiar with video coding performance know that, in many circumstances, people’s perception of visual quality is more sensitive to incremental color depth than to incremental spatial resolution. Ultimately, when quality is lacking because of too low a bitrate, incremental increases in bitrate are likely to produce better perceived quality when the spatial resolution is held fixed than when the spatial resolution is increased.
Speaking as a Netflix user with a trained eye, while visual quality is often excellent, it is also frequently merely good, with visible contouring—an artifact that occurs when color depth is inadequate. Since I access Netflix via their top-ranked cable (and #2 overall) ISP, I have to assume that my experience is typical (or better than) the vast majority of Netflix subscribers. And if it is, it’s hard to imagine that offering a 4K resolution feed at 15.6 Mbps is going to translate into a meaningful benefit for subscribers anytime soon.