Mukesh Sharma, Additional Director General, Doordarshan

Doordarshan, the Public Service Broadcaster of India, has a huge repository of video/audio content dating back from the analog Ampex days to the recent-born digital days. The content is available in multiple of mediums/formats such as Ampex, BCN, U-matic, Betacam, DVCPro to the current XDCAM, SSD, HDD mediums, and formats. This multi-medium/format of content is a serious challenge for migration to digital technologies where the old analog content along with the recent-born digital content can be effectively stored and repurposed.

Doordarshan’s workflow from content gathering to transmission can be broadly divided into few major work areas, such as shooting (rushes) and acquisition of content, editing/post-production, archive/storage of edit-masters, and transmission/broadcasting. In each of these areas, tape has traditionally played a major role. The video/audio content is stored in physical tapes and exists on the shelves, tagging done on pieces of paper to describe the content.

A majority of Doordarshan Kendras still continue to use tape-based camcorders, though at certain points in the production workflow, there is greater use of computers and networks to take certain of the advantages of IT. Nevertheless, the end product in the workflow is always taken out in the form of tape, as psychologically, tapes provide a sense of surety and give physical backup in the event of something going wrong in computers and networks.

Doordarshan, as a continuous process, has been adopting all the evolving video recording formats/medias. It has also done the work of transferring of content from older systems/medias to evolving newer systems/medias. Much of the BCN, U-matic, and Betacam content has already been digitized to DVCPro50 format by transferring it to DVCPro tapes. However, there are still many hours of content in old analog modes. Recently, a few local Doordarshan stations have started transferring content from DVCPro to XDCAM system, thereby moving from tape base to optical media.

Digitizing the old analog content and migration from one media type to another makes provision for the availability of the content a bit longer – till the time a newer and efficient medium of storage supersedes the older ones, thereby needing another cycle of migration. Digitizing may also help the content to see lesser quality loss while coping, but digitization by itself alone cannot exploit all the benefits that the IT world can provide. Tape being a linear device, accessing content stored in tapes is sequential, hence it takes longer time, thereby making tapes unsuitable for on-demand services.

But the advent of file-based workflow is changing all that. Content is more subtle now; it no longer exists on a shelf. It is very important to mark up and describe video footage for its identification in the workflow, and if not done, probably the footage would never be found. Move from tape to tapeless file-base requires to ensure adoption of proper security measures for the content. With a proper understanding and adoption of the file-based workflow, the rewards are too many and ensure all the benefits of IT. Doordarshan, as a step toward file-based workflow, has introduced camcoders and decks based on XDCAM HD422 format with MXF OP1a wrapper, which store media files in optical media. It has also camcoders based on AVCHD format storing media in memory cards. As the older medias (which are both in analog/digital tape format) need to co-exist with the recent-born file-based digital content, a mechanism was needed to be developed to digitize the analog tapes to file-based formats with proper meta tags and security.

Doordarshan also requires to repurpose its archived content for its day-to-day transmission. This needs packaging of the content before being delivered to the channel playouts. In order to use standard IT equipment and use cheaper storage and network solutions, editing for packaging in low-resolution proxies is suggested with the EDL getting reflected on the corresponding high-res content in the back-office media operations.

To achieve the above objectives, DD is in the process of procuring various components of the file-based workflow, such as storages, network components, tape cleaning machines, ingest systems, file-based quality control system, transcoders, media asset management, playout automation, etc.


 

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BroadcastAsia 2017

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