n s presentation, though this
could change at any time.
Ditto for Microsoft Edge
on Windows 10 platforms
with HEVC hardware support, which can play HEVC
streams, just not HEVC in
HLS. Once you have the
encoded HEVC streams,
you should be able to trans-mux into DASH for delivery to both platforms,
though that adds another
process into the mix.
2. What’s the Effect on Battery Life?
To understand battery life, we compared
CPU utilization between H.264 and HEVC
playback for the Streaming Media West session with positive results, which you can read
about in the article “HEVC in HLS: How Does
It Affect Device Performance?” ( go2sm.com/
hlsbattery). The pithy summary states, “
Overall, while you may have issues with the oldest generation of supported mobile devices
and computers, the next generation in all cases show only a slight increase in CPU utilization for HEVC playback, while new iPhones
at least show relative parity. Publishers considering deploying HEVC should do so without
concerns that the higher-end format will create significant battery life issues for most potential viewers.”
3. What Does Supporting HEVC Get Me?
Supporting HEVC will deliver multiple benefits, including economic savings and service
Bandwidth Savings: HEVC should deliver
some bandwidth savings, though the benefits
will vary from service to service and will depend on multiple factors. In terms of compression performance, HEVC should deliver about
the same quality as H.264 at substantially lower
bitrates, as much as 50% lower at 1080p, though
this will drop substantially at lower resolutions.
To determine how much actual bandwidth this
will save you, you’ll have to start by check-ing your server logs to see the distribution of
streams that you’re currently delivering.
At one end of the spectrum, assume that your
typical viewer is watching a 4Mbps 720p H.264-
encoded stream. Switching to HEVC would de-
liver little bandwidth savings because after mak-
ing the switch, you would likely be delivering a
1080p 4Mbps stream. While the perceived qual-
ity of the stream would increase, the bandwidth
would be the same.
On the other hand, I recently chatted with
an OTT provider in Denmark who reported
that 93% of streams delivered were the highest quality 1080p H.264 stream available, which
was encoded at 8Mbps. In this case, bandwidth
savings could be close to 50% because the service could deliver the same video quality using
HEVC at about half the bandwidth.
Quality of Experience Benefits: Quality of
Experience (QoE) benefits also depend on the
streams that you’re currently delivering. In the
case of the Danish OTT provider, QoE would
vary very little since the perceived quality of the
1080p H.264 stream encoded at 8Mbps would be
nearly identical to the 1080p HEVC stream encoded at 4Mbps (see Table 1).
On the other hand, if you’re currently delivering mid-ladder streams to your mobile customers, the QoE benefits could be quite substantial,
as you can see in Table 1. Briefly, to complete
the table, I produced optimal encoding ladders
in both H.264 and HEVC for two test clips, Tears
of Steel and Sintel. Then I computed the VMAF
score for each clip, with the Delta column on
the right showing the improvement from using
HEVC instead of H.264.
By way of background, VMAF scores of six
or more represent a just noticeable difference
(JND), which means that 75% of viewers would
notice the difference. By using higher-resolution
streams for HEVC at 365-2000Kbps, the QoE benefits are quite substantial. On the other hand, as
previously mentioned, when both codecs are
from using HEVC
rather than H.264