A look back at innovations in video compression technology over the years.
Frank Schöenberger*
The broadcasting industry would not be what it is today without video compression. This is a fundamental process that allows you to convert large video files to a more manageable size for transport, storage, and transmission. Today's cutting-edge video compression technology makes it possible to meet the needs of millions of people around the world, enabling the efficient delivery of high-quality content.
Video technology has transformed significantly over the years, moving from analog to digital and subsequently, as compression technology advanced, enabling the delivery of streaming content. But how did we go from the release of MPEG-1 some thirty years ago, designed to compress raw digital video and audio with VHS quality, to the advanced compression technologies we see today? And what's next in the future of video compression?
Rise of Digital TV
In the mid-1990s, the use of the internet became considerably widespread, and fiber optic networks began to be installed that allowed data transfer at speeds much higher than conventional cable to meet consumer demand. Broadcasters and media companies were just beginning to experiment with using the U.S. standard for analog television, NTSC, and SMPTE's ST-259M standard, on new fiber networks.
These networks marked a significant turning point by initiating the transition from coax and other copper-based systems to digital transmission. Fiber networks opened up new opportunities, particularly for the transport of the first digital signals, but at the time, the industry was still operating without standardized digital compression methods.
Solutions for digital video transport were just emerging, laying the groundwork for more efficient and scalable methods. It wasn't until the emergence of digital compression standards like MPEG-2 that we began to truly discover the potential of efficient video streaming. That's when the real digital TV revolution began.
Released in 1996, MPEG-2 was designed to provide a standardized method of compressing and transmitting video and audio, allowing streaming-quality video to be compressed without significant loss of visual or audio quality. Its use was widespread on DVD, as well as in digital terrestrial, cable and satellite television transmissions, laying the foundations for the generalization of digital television. MPEG-2 introduced the adaptive DCT encoding scheme with prediction with motion compensation, which significantly reduced the bitrate required for video streaming. In this way, broadcasters and service providers began a major transition, marking the beginning of the era of digital television and the subsequent decline of analogue systems.
MPEG-2's impact on the industry was profound. It enabled the efficient transmission of content in standard definition and, to some extent, high definition, dramatically reducing bandwidth consumption and storage costs. Digital television and early video-on-demand services were based on this compression standard, and for more than a decade, MPEG-2 remained the gold standard for video compression.
Streaming Revolution: AVC and HEVC
In 1999, the MPEG-4 standard was released, which allowed for higher coding efficiency compared to its predecessor, MPEG-2. Like all MPEG standards, MPEG-4 is made up of several parts, and in 2003 MPEG-4 Part 10, or Advanced Video Coding (AVC), also known as H.264, was released. While MPEG-2 is still used today for over-the-air digital television transmission, AVC has become the preferred standard for video compression, both for television transmission and streaming. It enabled the efficient distribution of content over the internet and laid the groundwork for the rise of OTT services such as Netflix, Amazon Prime, and Disney+.
The efficiency of H.264 is due to the use of advanced algorithms that reduce file sizes, maintaining or improving image quality. It made streaming a viable option for consumers and fundamentally changed the way we produce, distribute, and consume media content. The ability to stream high-quality video at low bitrates became crucial as streaming services began to expand globally. It was during this period that IP-based transportation really began to take off, and the industry experienced a rapid transition to more efficient and network-compatible delivery models.
Following in the footsteps of H.264 is High Efficiency Video Coding (HEVC), or H.265, which improves on H.264 by offering even greater compression efficiency. It allows broadcasters and streaming services to deliver ultra-high-definition content without overwhelming networks. HEVC's efficiency improvements made 4K live streaming and high-resolution streaming possible, although it still faces challenges in the patent arena.
Today and in the future
As video delivery continues to evolve, so do its underlying technologies, and VVC (Versatile Video Coding), also known as H.266, is the next big codec supporting this evolution. Designed for even greater efficiency with resolutions up to 8K, VVC pushes the boundaries of efficiency, significantly reducing file sizes and bandwidth consumption compared to HEVC.
With maximized visual quality and higher resolutions in mind, VVC has standardized to adapt to changing ways of creating and consuming video. With compression improvements of up to 40%, VVC enables a wide variety of use cases and paves the way for cost-effective and efficient production workflows.
Multiview HEVC (MV-HEVC), an extension of HEVC, is another development to highlight. With growing support from major companies such as Apple, which uses MV-HEVC in its Apple Vision Pro, the codec efficiently compresses the large amounts of data needed for 3D video by reducing redundant information across multiple views.
This enables high-quality extended reality (XR) content with lower bandwidth requirements, helping to make immersive experiences more accessible to a wider audience. Although MV-HEVC is still in development, its growing popularity suggests a future in which XR experiences will become more widespread, driven by advances in immersive content that enrich users' interaction with virtual worlds. All in all, the development of MV-HEVC marks a transformative shift in the video industry, with immersive real-time experiences going mainstream.
Looking ahead, the industry also appears to be moving toward compression technologies that harness the power of AI and cloud-based technologies to dynamically adjust video quality and compression in real-time based on network conditions, viewer preferences, and content complexity. We'll undoubtedly see more and more real-time optimizations that intelligently adapt to a wide variety of delivery environments.
As the broadcasting industry continues to evolve, innovations in video compression will remain at the forefront, helping to redefine the way the industry delivers video and how consumers experience it. The future of video compression offers endless possibilities, enabling more flexible, scalable, and cost-effective ways to deliver engaging, high-quality, and immersive content to audiences around the world.
*Frank Schöenberger is Senior Product Manager at MainConcept.
