Shorter and simpler - DD Trivandrum devises new technique in Point-to- Point video streaming
The Production control room PCR2 at Droordarshan Trivandrum seemed as busy as you would expect it before any live telecast. It was 1110 hours and a short news bulletin had just ended. Some fillers before a 'live' programme went on air. The monitors and computer screens were all glowing, and the sound from various sources being tested echoed in the room. I found the VM and Audio engineers hurriedly making the final adjustments. Anjusha Abhilash, Programme Executive was already on the production panel and Ranjith Ravi, Programme Executive who coordinated the show on Covid-19 was standing beside her, giving suggestions.
Like DD Kendras elsewhere in the country this Kendra too had taken measures that comply with the government norms in the fight against the pandemic. The aroma of sanitizers was lingering in the air. People were seen wearing face masks except the participants of the show, visible in camera output monitors. I could recognize George Onakkur, a man of letters sitting in studio sets beside the anchor, waiting for the live to begin. The subject on that day was related to constructive spending of the lock down period by engaging in reading. The programme 'Athijeevanam' (survival) covered all aspects of the ongoing fight against the pandemic. This newly started live at 1120 hours included panel discussions on Covid-19 related subjects and many informative videos. The programme also contained a lot of small video footages sent by keralites living in the pandemic affected foreign countries.
About 280 kilometers away, at Droordarshan Trichur, another studio was becoming ready with two more participants for this same show. V G Thampi, a poet and Rosy Thampy, an author, both sitting there could be seen on monitors at PCR2 Trivandrm. They would be participating in the live discussions that was to happen at Trivandrum soon. These two studios were connected. Ranjit Ravi called the panel producer at Trichur on mobile. K Sreekumar, Programme Executive was the panel producer at that end. "Let's have a trial, ask them to say something for an audio test"
Live discussions with people participating from distant places is nothing new. All leading channels including DD do it, at times. If the remote station doesn't have a satellite uplink facility at their disposal, such a hot switching becomes expensive. It requires DSNG deployment, or OFC-hiring. But here, these two studios were connected with no such conventional things. The output from DD Trichur reached at PCR of DDK Trivandrum through a network cable. The signal came through internet. What I witnessed was a point-to-point video streaming.
Some time back, the IT team at DDK Trivandrum had developed a simple system to transfer recorded Videos from the other two DD studios in Kerala, DDK Calicut & DDK Trichur to DDK Trivandrum using BSNL FTTH Connections. The same system could be used to transfer live signals. Now, for the past many days for the production of the Covid-19 related live program, Athijeevanam, DDK Trivandrum had been using this improvisation.
In this era of social media, people are familiar with video streaming on YouTube and Facebook. Video streaming is a way to deliver audio/video over Internet to reach millions of viewers. The viewers watch them on their PCs and smartphones. Unlike what happens on social media platforms, this video streaming technique developed at DDK Trivandrum is 'point-to-point' in nature and no external player other than the internet provider, BSNL, has a role in it.
I met the team that realized this novel idea, of video-linking two places through internet, at IT Room of DDK Trivandrum. The IT Room seemed as a congested space, irregular in shape and appears to have been built in some leftover space between an AHU room and Toilets. In addition to the IT related works, most of the social media activities of the station are done in this room. You wouldn't expect innovations originate in such a room. But DD has limitations. We must cope with the reality first and then try to circumvent the limitations.
"It began with an open challenge from the DDG(E) at the time of General elections-2019." explained C Radhakrishna Pillai (RKP), Assistant Engineer who heads the IT Team. "He had asked us to find alternative, less expensive ways to bring in news feeds from distant places to DDK and we, the IT Team here took the challenge up". The elections in Kerala had always been in national focus and the candidature of Rahul Gandhi from the state brought added attention on this state. The counting, discussions on it and reactions of prominent people from all over the state needed to be covered. However, DDK Trivandrum possessed limited DSNG facilities at their disposal and hiring OFC was too expensive. "We acted fast, had a research on whatever infrastructure we had. We studied all aspects of sending live feeds from one point to another. Finally, we zeroed in on streaming. DD had already hired a BSNL 100 Mbps broadband connection" RKP recollected.
Streaming refers to the process of delivering or obtaining media through internet. Here media stands for multimedia content that is constantly received by or presented to an end-user, while being delivered by a provider. Streaming is deemed as an alternative to file downloading. But in file downloading process, the end-user obtains the entire file for the content before watching or listening to it. "Imagine, you've got your A/V output at the sending end as SDI signal. Your mission is to take this signal to the receiving end, without losses. With the MPEG-2 standards that DD adopts, the SDI demands a high bandwidth in transmitting medium. To overcome this bandwidth constraints, here, we use IP streaming. Once converted as IP data packs, the signal can travel over internet to the destination,surpassing the bandwidth constraints" RKP explained.
"The extra hardware you need at the sending end is a capture card to which you connect your SDI output. We used a deck link card for connecting SDI and then you should have a suitable encoder software to convert this SDI into IP data" said P V Balakrishnan, (BKN), Senior Engineering Assistant. "After considering a few options, we selected one open source encoder software, that can serve the purpose, provided we customize it". The encoded signal finds its paths to the destination as mpeg transport stream. It reaches to the static IP address, configured as destination. "In real time protocol, RTP, you know." BKN continued, "it is then port transferred to the final destination, that is the PC at PCR2. He concluded. "At the receiving end we used a VLC player, suitably configured for playing back the decoded signal received from the remote sender." Vineesh Raj, Engineering Assistant intervened in the discussion. He is the youngest of the trio who are behind this achievement."Here, you can regenerate the SDI signal using a HDMI to SDI adapter on the PC".
But, is this cost effective, one might wonder. "It is a zero cost set up" said RKP. DD had hired a 100 Mbps FTTH line from BSNL and with that package they provide a static IP free of cost. The office hasn't spent an extra paise for realizing this", he added. "We wouldn't claim this is a substitute for DSNG or OFC connection between the two points. But it works! It serves our purpose as you have just seen it in PCR2". In the market an equivalent streaming set up costs around 7 lakhs where as DSNG deployment and hiring OFC are also costly affairs.
This mission was appreciated by the fellow engineers and seniors at DD Trivandrum. "Since the beginning, the Deputy Director General (E) S Sanjeev was very supportive and he kept on enquiring about our progress. As always, our Director (E), K Subramonian Iyer and Assistant Director (E), B Anilkumar generously provided all the help from their sides whenever we wanted them", RKP recollected.
This point-to-point streaming was used first time for live during the counting of General Elections-2019, and a couple of occasions since then. Recently, this streaming is being utilized for Athijeevanam, the daily live programme, to connect DD Trichur and DD Calicut with DD Trivandrum. The brilliance shown by these engineers in developing this innovative streaming technique is widely appreciated. They are ready to share their knowhow if any other DD Kendras are interested. The nation is amidst a fight against the pandemic and DD plays its role well. Even the Prime Minister has, recently, appreciated DD's role in this fight. No doubt, the sweat and sincerity of resourceful DD engineers and the brilliance shown by them are the real assets, not only of Doordarshan, but of the whole nation.