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Gary Sullivan: On Both Papers, Nine Years Apart

By Infinite Creation · Profile

At a Glance

Two video codecs dominate the last twenty years. Sullivan co-chaired the standardisation of both and is a named author on both overview papers, first with Wiegand in 2003 and again in 2012 with Ohm and Han. Continuity of that kind across two generations of a committee standard is rare, and it is most of the reason the second generation is a coherent successor rather than a fresh start.

Lived: born 1960, American
Anchor year: 2012, HEVC standard published
Strand: canon

Career

The problem as it stood

By the late 2000s H.264 had been squeezed. Displays were moving to high definition and beyond, and the previous codec could not deliver those resolutions at the bitrates networks actually had.

What he actually did

Sullivan co-chaired the Joint Collaborative Team on Video Coding, the body that produced HEVC, having previously co-chaired the group that produced H.264. He is first author on the HEVC overview paper and second on the H.264 one.

How it worked

HEVC roughly halved the bitrate again, largely by allowing much larger and more flexible block partitions than H.264's fixed sixteen-pixel macroblocks. The technique is not new. Being able to choose the block size adaptively, and having the computing power to search those choices, is.

What it made possible

HEVC is what carries most 4K delivery, and it is in broadcast, streaming and camera recording formats. Its adoption on the open web was slowed by an unresolved patent licensing position, which is a large part of why AV1 exists.

Where the credit landed

Chairing a standards committee is a peculiar contribution: it produces no technique of its own and determines almost everything about what the technique becomes. Sullivan's two papers are the clearest single record of that role in modern video.

Known For

HEVC's licensing position, not its quality, is why the open web went looking for an alternative.
Flexible block sizes are the main structural change from H.264.
The same two names appear on both overview papers, nine years apart.

Knowledge Base

What You'll Learn

Two codecs, nine years apart, with the same two names on both papers.

What a chair actually does

A standards chair invents nothing and decides almost everything: which proposals are tested, under what conditions, in what order, and when the specification is finished. It is closer to editing than to engineering, and it explains why the same names recur across generations of a standard while the techniques inside it turn over completely.

Where This Fits

H.264 and HEVC are the compression step in modern delivery, which A History of Broadcast Technology places in the wider chain.

FAQ

Q: Why did HEVC adoption stall on the web?
A: Its patent licensing position was unresolved for years across multiple pools. Browsers and open-source projects cannot ship what they cannot licence, so the open web went and built AV1 instead.

Q: Is HEVC better than H.264?
A: It compresses roughly twice as efficiently for the same quality. Whether that is decisive depends entirely on whether you can licence and decode it.

Vocabulary

HEVC A video codec published in 2012, also called H.265, which roughly halved the bitrate needed against H.264. It carries most 4K delivery, though patent licensing uncertainty limited its adoption on the open web.

Macroblock The fixed square unit older codecs divided a picture into, sixteen pixels across in H.264. HEVC replaced it with a flexible tree of block sizes, which is where most of its efficiency gain comes from.

Joint Collaborative Team A working group formed jointly by ITU-T and MPEG to produce a single standard rather than two competing ones. Both H.264 and HEVC came from bodies of this kind.

Patent pool A group of patent holders licensing jointly. When a pool cannot agree terms, as happened with HEVC, implementers stay away regardless of the technical merits, which is how licensing decides adoption.

Sources

Every record below was fetched and read before it was cited here. Checked 26 August 2026.

G. J. Sullivan, J.-R. Ohm, W.-J. Han and T. Wiegand, Overview of the High Efficiency Video Coding (HEVC) Standard. IEEE Transactions on Circuits and Systems for Video Technology, volume 22, issue 12, pages 1649 to 1668, December 2012. Sullivan and Wiegand appear on both this and the H.264 paper nine years earlier, with Ohm and Han added.
T. Wiegand, G. J. Sullivan, G. Bjontegaard and A. Luthra, Overview of the H.264/AVC Video Coding Standard. IEEE Transactions on Circuits and Systems for Video Technology, volume 13, issue 7, pages 560 to 576, July 2003. The author order is Wiegand, Sullivan, Bjontegaard, Luthra, on the paper that introduced the codec most video on earth still uses.