The complexity of modern video coding standards demands a great deal of engineering effort and skill to develop product-ready implementations of the standard. For example, to become production-ready a software codec implementation may need to be optimized to run thousands of times faster than the standard’s reference software. Products released shortly after the publication of a standard demonstrate commercial viability thereby facilitating adoption by other manufacturers who might otherwise opt not to risk using the standard.
In May of 2000 while at Polycom, Horowitz developed and demonstrated the first product-ready implementation of macroblock-adaptive multiple reference frames[11] overcoming concerns that its high computational complexity would prevent commercial adoption. The tool was published as Annex U of H.263. Macroblock-adaptive multiple reference frames is a mainstay of every subsequent video coding standard.
In 2003, while still at Polycom, he led the team that produced the first commercially available in-product implementation of H.264|AVC[12] demonstrating that the new H.264|AVC standard could be used successfully in real-time low-delay commercial products.
In 2008, at Vidyo, Horowitz architected and led the team that developed the first commercially available in-product implementation of H.264 SVC[13]
In 2012, at eBrisk Video, Horowitz served as lead engineer of the team that developed one of the first commercially available implementations of H.265|HEVC demonstrating that a real-time software implementation of the standard could yield high coding efficiency.[14].
In 2020, at Google, Horowitz served as technical lead of the AV1 for Google Duo project that became the first commercially available real-time interactive video implementation of AV1, dispelling the myth that older entry-level mobile devices did not have sufficient computational resources to support a real-time software implementation of AV1[15]. The AV1 implementation in Duo and subsequently Google Meet supports video calling at bit rates as low as 40 kilobits per second on modest entry-level mobile devices thereby enabling people to connect in regions of the world where video calls would not otherwise be possible.