Fact Check: Yedlin’s HLG Claims vs. Industry Reality
While we aren’t taking a position on HLG’s suitability for narrative streaming, we cannot remain silent in the face of persistent industry-wide inaccuracies. We clarify some of these points below.
REAL-WORLD ADOPTION
CLAIM
“There’s no real-world in-use path for images to be encoded in HLG at the final viewing stage. Consumer disks, streaming platforms, and theatrical ‘HDR’ are all encoded in PQ.”
REALITY CHECK
In addition to being the preferred HDR format for live broadcast, HLG is supported by YouTube for HDR delivery to capable devices across 2+ billion users, including HDR uploads from billions of iPhones and many modern Android devices worldwide.
According to the most recent documentation available, Sky UK HDR licensed acquisitions can be delivered as either PQ or HLG, while all HDR commissioned productions are required to be mastered with PQ ST2084.
That being said, all HDR deliverables are then conformed to HLG for publication on its platforms—decisively disproving Yedlin’s contention of “no real-world in-use path”.
Yedlin’s assertion of ‘no real-world in-use path‘ is central to his broader dismissal of HLG. Debunking this core premise essentially undermines his entire thesis.
CLAIM
“I was addressing problems with what’s substantively going on in the real world, not weird edge cases or hypotheticals.”
REALITY CHECK
HLG is not some “weird edge case“: it’s central to live sports, news, and events. Ignoring this misrepresents the industry. Industry bodies standardized Rec.2100, confirming its mainstream role.
TECHNICAL DEFINITIONS
CLAIM
“HLG is an alternate transfer function (not the main line; the main line is PQ).”
REALITY CHECK
Although PQ dominates pre-recorded streaming content, HLG is the primary HDR standard for live broadcasting (sports, news, events) – a distinct, critical domain.
CLAIM
“HLG (in effect if not in name) is just yet another SDR colorspace.”
REALITY CHECK
HLG is emphatically not “just another SDR colorspace.” HLG is an HDR format that uses the HLG transfer function and BT.2020 color primaries and was designed to be backward compatible with SDR displays.
Performance & Efficiency
CLAIM
“If you change only the SHAPE of the transfer function… there is no difference in what the system can do… The shape only effects efficiency.”
REALITY CHECK
Yedlin overlooks HLG’s perceptual benefits. Transfer functions define how luminance values are encoded. HLG’s logarithmic curve preserves highlight detail that SDR’s gamma crushes.
CLAIM
“The one and only thing that’s even a little bit different… is the efficiency of its curve which is worse than traditional gamma-style curves for most real-world applications.”
REALITY CHECK
To say that HLG’s hybrid log-gamma curve outperforms gamma for HDR would be an understatement of monumental proportions: BT.1886 is entirely unsuited to HDR, as it would exhibit atrocious banding artifacts.
General Observations
Yedlin’s claims about HLG suffer from three critical flaws:
1. Ignoring broadcast reality: HLG is central to live HDR delivery.
2. Misdefining technical terms: Conflating color spaces, EOTFs, and standards.
3. Overgeneralizing from artistic preference: Asserting HDR’s “detriments” based on SDR-centric workflows.
Yedlin: HLG “Inefficient”
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