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Thomas Wiegand: The Codec Most Video Still Uses

By Infinite Creation · Profile

At a Glance

H.264, also called AVC, was published in 2003 and is still the most widely deployed video codec in the world. Newer formats compress better, but H.264 decodes in hardware on essentially every device ever made, and that is a harder advantage to beat than efficiency. Wiegand chaired the standardisation work at the Fraunhofer Heinrich Hertz Institute and is the first author on the overview paper.

Lived: born 1970, German
Anchor year: 2003, H.264/AVC standard published
Strand: canon

Career

The problem as it stood

MPEG-2 was built for broadcast and DVD, at bitrates that made no sense for the internet. Video over a domestic connection needed roughly half the data for the same picture, and the previous generation had no more room in it.

What he actually did

Wiegand led the joint standardisation effort between ITU-T and MPEG that produced H.264. The gain came not from one idea but from many small ones combined: variable block sizes, quarter-pixel motion, multiple reference frames, and an in-loop filter that removes the blocking the codec itself creates.

How it worked

A video codec predicts each frame from what came before, then codes only the error. H.264 made the prediction much better and the error therefore much smaller. Nothing in it is conceptually new. The engineering is in getting a dozen refinements to work together without the complexity becoming unusable.

What it made possible

H.264 is what made internet video ordinary. YouTube, Blu-ray, broadcast contribution, video calling and most security cameras run on it, and hardware decoders are in every phone and television sold for two decades.

Where the credit landed

The paper names four authors and the standard names hundreds of contributors across two committees. Wiegand is credited more than the others because he chaired, and chairing a standards body is a real contribution that is different in kind from inventing a technique.

Known For

Hardware decode support beats compression efficiency. That is why H.264 outlived better codecs.
The gain came from many small refinements, not one breakthrough.
Two standards bodies produced it jointly, which is why it has two names.

Knowledge Base

Going Deeper

H.264 is the format almost every other page in this corpus eventually becomes.

Why an old codec is still the default

Hardware decoders for H.264 sit in every phone, television, camera and browser sold for twenty years. A newer codec must be decoded in software until silicon catches up, which costs battery and heat. Compression efficiency is only one term in that equation, and usually not the deciding one.

Where This Fits

H.264 is the compression step most video still passes through, a link covered in A History of Broadcast Technology.

FAQ

Q: Is H.264 the same as AVC?
A: Yes. ITU-T calls it H.264 and MPEG calls it MPEG-4 Part 10 Advanced Video Coding. One standard, produced jointly, with two names.

Q: Why has nothing replaced it?
A: Newer codecs compress better but face either patent licensing uncertainty or missing hardware support. H.264 has neither problem, which has kept it in place far longer than anyone expected.

Vocabulary

H.264 A video codec published in 2003, also called AVC, jointly standardised by ITU-T and MPEG. It roughly halved the data needed for a given picture quality against the previous generation and remains the most widely deployed video format in the world.

In-loop filter A smoothing stage applied inside the coding loop rather than after it, which removes the block edges the compression itself creates. Because it runs inside the loop, later frames predict from the cleaned picture rather than the damaged one.

Motion compensation Coding a frame by describing how blocks of the previous frame moved, then coding only what that prediction got wrong. Almost all video compression is this idea plus the transform that codes the remaining error.

Standards committee A body in which competing companies agree a common specification. The output is technical, but the process is negotiation, and chairing one is a distinct skill from inventing the techniques it selects.

Sources

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

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.
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.