Streaming Forum Preview: Producing and Distributing HEVC
Covering a dry subject like a new codec in the very last session of a two-day conference like the Streaming Forum is a ordinarily a risky proposition; delegates are tired, attention spans limited, and it’s close to the magical 5 p.m. hour in central London. Fortunately, there’s enough controversy surrounding HEVC to hold the attention of anyone with even a casual interest in streaming media. Though HEVC burst into the scene like an irresistible force, it now feels more like an immovable object. How soon till HEVC becomes relevant? I’ll put it this way; with HEVC, objects in the mirror may be further than they appear.
Let’s start with the quality, the raison d'etre, the sine qua non of any new codec. Expectations have been that HEVC will deliver quality equivalent to H.264 at 50% the data rate, just as H.264 did with MPEG-2. How’s that working out so far? Well, as you’ll learn in this session, most encoding companies have been backing off this claim, moving towards the “same quality with a 35% reduction in file size range.”
Still impressive, of course; I’m sure anyone paying big pounds or Euros for bandwidth would love a 35% cost reduction. However, my tests reveal there’s a reason that encoding vendors quote only still-image metrics like PSNR and SSIM figures in support of their HEVC/H.264 findings; in some instances, particularly with slow pans, HEVC produces significantly more motion artifacts like mosquitoes than H.264, even at near equivalent data rates. I’ve found this effect in my 720p and 1080p clips encoded with multiple HEVC codecs from multiple vendors.
I don’t want to oversell this point; HEVC is a moving target, as are my tests. At the Streaming Forum, however, I’ll reveal updated test results from multiple vendors on existing 1080p and 720p test clips, as well as a new 4K test clip. You’ll be able to view all tests at the session and download some of the clips for your own comparisons. Until then, I will say this; don’t reach any quality-related conclusions about HEVC based solely on still-frame comparisons; the motion story is significantly different.
I'll also hopefully be sharing some of the results of a survey we just launched on Streaming Media to gauge industry adoption of HEVC.
Beyond quality, HEVC also has royalty related issues. Back in January, when MPEG LA announced their intended policy, it felt like knowing what was intended would help accelerate market adaption. Upon reflection, the announced royalty policy will likely delay the availability of free HEVC playback in the streaming space, perhaps in perpetuity, and/or signal the demise of browser vendors like Opera and Mozilla. As you undoubtedly remember, free playback in Flash lit the fuse on H.264’s meteoric rise; clearly, this same dynamic for HEVC is not in the works. I’ll explain why in the session.
All this, of course, relates to HEVC patent group represented by MPEG LA. As you’ll learn in the session, there are multiple high-profile holdouts with war chests more than sufficient to challenge any well-heeled HEVC adapter who doesn’t pay their as yet unspecified royalties.
Once the clear codec heir apparent, HEVC now has more hair on it than an ungroomed Pomeranian. Get updates on all these issues at my session at the Streaming Forum. Despite being the final session, you won’t have any trouble staying interested or awake, and I assure you, the pubs will still be open after I finish.
Streaming Forum will be held at the Park Plaza Victoria in London on 24-25 June. "The Second Screen: More Important than the First?" will be at at 4 p.m. on Tuesday, 24 June.