Papercup

Papercup (Papercup Technologies Ltd.) was a London-based machine learning company that built an AI dubbing and synthetic speech platform. Customers uploaded video, selected a target language and received a translated version with a synthetic voiceover intended to reproduce the original speaker's tone, pacing and emotion rather than a generic text-to-speech read. The company described its aim as making video content watchable in any language, arguing that the large majority of video and audio content is confined to a single language and that only a small share is dubbed into multiple languages.

The platform combined speech synthesis and translation models with a "human-in-the-loop" review layer, in which people corrected speech-recognition and machine-translation errors, adjusted audio timing and speed, and enforced emotional delivery, with the amount of human involvement varying by content type and customer requirements. Papercup pitched this hybrid approach as a lower-cost, more scalable alternative to professional dubbing studios and voice actors, aimed particularly at the mid- and long-tail of content owners for whom traditional dubbing was uneconomic.

Applications spanned entertainment and news video, online education and training and marketing content. Reported users included Sky News, Discovery, Business Insider, Bloomberg Media and YouTube creators such as Yoga with Adriene, and the technology was used to translate 30 seasons of Bob Ross's The Joy of Painting.

Founding story

Co-founder and CTO Jiameng Gao completed two master's degrees at the University of Cambridge, in machine learning and in speech and language technology, writing a thesis on speaker-adaptive speech processing, and concluded there that the technology was feasible. He and Jesse Shemen began working together at Entrepreneur First at the end of 2017 and built initial prototype systems demonstrating the approach, with early customer conversations indicating demand.

Business model

Papercup sold AI-assisted dubbing and video localisation to content owners, delivering translated audio tracks produced by its speech synthesis models and refined through a human-in-the-loop quality control process; positioning emphasised cost and turnaround advantages over studio dubbing with voice actors.

Sold dubbing and video translation services to content owners and media companies, positioned as a lower-cost alternative to professional dubbing studios.

Traction

More than 300 million people were reported to have watched Papercup-translated videos in the 12 months to mid-2022, and by 2025 the company said customers had collectively reached over a billion views on Papercup-translated videos. Named users included Sky News, Discovery, Business Insider, Bloomberg Media and YouTube creators, plus 30 seasons of The Joy of Painting.

Latest developments

On 15 May 2025 CEO Jesse Shemen announced that a large portion of the Papercup team was joining Scale AI, which published a corresponding welcome announcement the same day. RWS subsequently acquired Papercup's intellectual property, reported in June 2025; RWS CEO Ben Faes said the company intended to integrate the hybrid AI dubbing capability into its existing language technology suite, which includes Language Weaver and Trados, and offer it to its client base.