Dalet has supplied and integrated an end-to-end workflow for CPAC’s (Cable Public Affairs Channel) English and French closed captioning.
The solution combines the Dalet AmberFin and Dalet Galaxy, designed to provide an automated workflow that maintains genealogy and captioning data for the 24/7 operation.
Based in Ottawa, CPAC is Canada’s only privately owned, non-profit, bilingual television service providing a commercial-free window on parliament, politics and public affairs.
It is delivered by cable, satellite and wireless distributors to more than 11 million homes in Canada and worldwide via 24/7 web streaming on the CPAC TV 2 Go mobile app and the CPAC website.
The organisation ingests up to 80 hours of new content daily and has made over 30,000 hours of archived content available on these digital platforms.
“We urgently needed a closed captioning solution that could manage a variety of content from several different types of production workflows: news and magazine-style shows, live and studio production, and long-form programming, said Eitan Weisz, senior manager of broadcast operations, CPAC.
“For each of these workflows we needed to be able to manage, and more importantly maintain caption data, especially after editing has been completed or the content is passing through another system.
“Those are all facets that we felt Dalet could deliver for us in one package.”
The solution devised by Dalet in concert with CPAC deploys Dalet AmberFin as an advanced media and processing platform for insertion and extraction of caption data, leveraging the existing Dalet Media Asset Management (MAM) deployment to manage transformation and distribution in an end-to-end media workflow with a key emphasis on maintaining captions as metadata.
During live shows or events, CPAC content is transcribed by operators using keyboard or stenography methods to generate live captions. Live feeds with captions are ingested into Harmonic and Dalet Brio video servers and written to an MXF file including a standard SMPTE ST436 data track. For pre-produced content, a proxy file is sent to an external captioning house for transcribing and generation of a separate caption file.
Where the Dalet MAM detects valid ST436 data, Dalet AmberFin automatically extracts the caption information to a standard SCC caption file, associated with the relevant video file in the MAM. Also automatically generated is TTML (Timed Text Markup Language), a standardised XML structure that represents all the captioning information as time-coded metadata that can easily be catalogued, searched and modified.
“The TTML pivot format is vital. Instead of keeping the information at file level, we expose it as timed metadata to the user so that they can directly view and search it as well as perform basic editing and correction of the caption information,” explained Dalet sales director Frederic Roux. “CPAC has rich automated metadata created in the Dalet system and tagged to all its content through this captioning process.”
