The modern content production process involves substantial amounts of collaboration. Whether it’s shipping out some special effects, accessing some overseas tax breaks, getting the perfect sound studio, or just working with a ‘must have’ editor or DI suite who happens to be based far away – it’s become an essential part of the content creation process to work remotely. There are many different ways of delivering effective remote collaboration, and at some level they all involve the same concept – getting people in the same room – physically or virtually.Achieving this physically is well understood – get on a plane and rack up the frequent flyer miles, hotel bills and the associated jet lag. But increasingly content creators are turning to the virtual approach to save time and money – as well as reduce the stress of constant travel.
SKYPE TO THE RESCUE?
Interest in Internet video conferencing has been stimulated by the many free services now commonly available, and as a result Internet video calls are now commonplace. But what are the requirements for video conferencing in the world of high quality content creation?
We have all experienced the great variability in quality and performance of the various free services currently available (Skype, Facetime, Google Hangouts, etc). They work great for calls to friends and family, but fall short when you are looking for reliable high quality video and audio.
So interest turns to higher quality solutions, generally based around quality codecs and and IP-based streams. There are a variety of products in the market that will take an HDSDI video stream, or even files in MPEG, etc. and turn it into an IP-based video stream. This can then be sent over any network, including the Internet, and decoded at the other end into a high quality image stream on a suitable monitor. These devices are designed to work at a variety of bit rates to allow for quality and network to be matched.
WHAT ABOUT THE NETWORK?
Matching the network throughput and video quality is really important because if high quality images are sent down a poor network, image quality will be severely degraded or you may not get anything at all. There are three key network parameters that are important when looking to stream IP-based video streams, and they pretty much apply to all devices. They are:
Each of these parameters will have an impact on the quality of the IP-based stream. Available bandwidth is an obvious consideration, but what is particularly important is sustained bandwidth – if it varies for any reason it can impact the stream significantly. Latency is similarly important and most good codecs can deal with some level of latency, but high variability can cause major issues. Finally packet loss can generate significant challenges (typically caused by congestion) and again devices can cope with a small amount of packet loss but if it increases materially or varies widely it can cause major video playback issues.Most professional devices have built in compensation to deal with small levels of these issues – but there is a trade-off. The more they have to compensate for poor network, the poorer the final video quality and the greater the delay through the device. For interactive sessions these delays can make remote sessions unworkable, and variations in quality can wreak havoc with the decision making process, turning remote collaboration into a frustrating process. These three issues – Bandwidth, Latency, and Packet Loss – are unfortunately an inherent part of the Internet, which by design is a “best effort” network. Most of the Internet focused applications are designed around this principle – hence the stop/start, quality variations, and lipsync issues we all see with Skype, Facetime, etc. Increasing the available bandwidth, which can reduce the affect of the packet loss, may result in some degree of performance improvement, but this “overprovisioning” to solve the problem can be expensive,for what can be an unreliable fix, because congestion can occur in many places between the two endpoints of the video conference. The most reliable solution to the network side of the problem is to have a dedicated network, where Bandwidth, Latency, and Packet Loss are tightly controlled and therefore the performance can be guaranteed.
IS SECURITY IMPORTANT?
Another important aspect of the network that cannot be ignored is security. Whilst it is difficult to intercept IP-based streams on the open Internet, its does happen, and they can be a target to sophisticated hackers looking for valuable content. Work in progress can carry a high premium and can be even more damaging than finished content, and therefore needs careful protection. Running these streams across the Internet exposes an additional layer of risk; in contrast a private network significantly reduces the risk profile of these kinds of interception attacks.These devices will also need to have a firewall in place, for which the configuration and setup is vital to ensure the integrity of the local networks at each end in order to prevent unauthorized access to local networks. Firewalls also need to be well matched to network throughput to ensure they are sufficiently powerful to not cause network issues.
HOW IMPORTANT IS THE WORKFLOW?
Assuming that we have an appropriately configured network in place, we can turn our attention to devices and work on ensuring that they are well matched to collaboration needs. Sohonet have carried out many tests for their clients on a variety of workflows, and have established criteria which is used as a guideline for discussions. As an example, for remote grading applications, Sohonet have established that around 70-100 Mb/s with appropriate quality codecs provides a “sweet spot” in terms of cost benefit for 2K editing workflows. Other workflows (3D, 4K, full color correction) may require a higher encoding rate.
Another important consideration that is easily overlooked is audio. Sohonet recommends devices that embed the audio in the IP-based stream – that way there is no possibility of the audio moving out of sync with the image stream. Of course that assumes there are good quality audio devices at each end of the encoding-decoding stream, and again these are an important part of the solution.Finally, assuming devices and network are matched well, we need to decide how to configure a workable solution for each workflow. If this is being used for a review and approval process, or remote editing or color grading, we need very high quality images in one direction, but the ability for there to be two-way communication on lower quality video conferencing. Visual cues are vital if there is to be good communication – body language often tells much more than the verbal ‘yeah, looks good’. There is a temptation to resort to Skype or similar for this, but our clients have found that this detracts significantly from the creative process when you have great high quality images on one screen and an out of sync image on another. If you have a good network provisioned, it is much more efficient to match this to a high quality video conference solution, providing excellent two way visual and verbal communication between the sites to sit alongside the high quality ‘creative’ images.
We have the following elements all of which need to come together to provide an effective ‘virtual’ opportunity for remote collaboration to take place:
High-quality encoders and decoders
A well-matched dedicated and secure network
High throughput firewalls and strong security practices
Audio and video combined in a single data stream
A separate high quality two-way visual and verbal communication channel (video conference)
Exploring these options and then procuring, configuring, installing, and maintaining them can be a hurdle for any organization, especially if the need is project driven (i.e. not permanent). Sohonet has made that easier for clients by launching a fully integrated opex-based solution that can be configured on a short or longterm basis terms to match your project needs. Sohonet ClearView has been extremely successful in customer implementations so far, with all the complexity of the solution taken away to allow clients to concentrate on the underlying creative process. Deployment times as quick as a week ensure that we can have a fully managed and supported system up and running to solve nearly any production need.David Scammell, CEO at Sohonet