By Jonathan Abrams
My interest in Streambox originated with their social media publishing capabilities (Facebook Live, YouTube Live, Twitter). I was shuttled to an unsecured, disclosed location (Suite 28140 at The Venetian) for a meeting with Tony Taylor (business development manager) and Bob Hildeman (CEO), where they were conducting user-focused presentations within a quiet and relaxing setting.
The primary use for Streambox in post production is live editorial and color review. Succinctly, it’s WebEx for post. A majority of large post production facilities use Streambox for live review services. It allows remote editorial and color grading over the public Internet with Mezzanine quality.
The process starts with either a software or hardware encoder. With the software encoder, you need to have your own I/O. As Bob mentioned this, he reached for a Blackmagic Design Mini Converter. The software encoder is limited to 8 bits. They also have two hardware encoders that occupy 1 RU. One of these can work with 4K video, and a new one shipping in June that uses a new version of their codec and works with 2K video. The 2K encoder will likely receive a software upgrade eventually that will enable it to work with 4K. All of their hardware encoders operate at 10 bit with 4:2:2 sampling and have additional post-specific features which include; genlock, frame sync, encryption and IFB audio talkback capabilities. Post companies offering remote color grading services are using a hardware encoder.
Streambox uses a proprietary ACT (Advanced Compression Technology) L3/L4 codec and LDMP (Low Delay Multi Path) protocol. For HD and 2K contribution over the Public Internet, their claim is that the ACT-L3/L4 codec is more bandwidth- and picture quality- efficient than H.264 (AVC), H.265 (HEVC), and JPEG2000. The low, and most importantly, sustained latency of the codec is in the use of LDMP (Low Delay Mutipath) video transport. The software and hardware decoders have about two seconds of latency, while the web output (browser) latency is 10 seconds. You can mix and match encoders and decoders. Put another way, you could use a hardware encoder and a software decoder.
TCP (Transmission Control Protocol), which is used for HTTP data transfer, is designed to have the receiving device confirm with the sender that it received packets. This creates packet redundancy overhead that reduces how much bandwidth you have available for data transmission.
Recovered packets in FEC display artifacts (macro blocking, buffering) when network saturation becomes problematic during playback. This does not generally effect lower bandwidth streams that use caching topology for network delivery, but for persistent streaming of video over 4Mbps this problem becomes apparent because of the large bandwidth that is needed for high-quality contribution content. UDP (User Datagram Protocol) eliminates this overhead at the cost of packets that were not delivered being unrecoverable. Streambox is using UDP to send its data and the decoder can detect and request lost packets. This keeps the transmission overhead low while eliminating lost packets. If you do have to limit your bandwidth, you can set a bitrate ceiling and not have to consider overhead. Streambox supports AES128 encryption as an add-on, and the number of bits can be higher (192 or 256).
Streambox Cloud allows the encoder to connect to the geographically closest cloud out of 10 sites available and have the data travel in the cloud until it reaches what is called the last mile to the decoder. All 10 cloud sites use Amazon Web Services, and two of those cloud sites also use Microsoft Azure. The cloud advantage in this situation is the use of global transport services, which minimize the risk of bandwidth loss while retaining quality.
Streambox has a database-driven service called Post Cloud that is evolving from broadcast-centric roots. It is effectively a v1 system, with post-specific reports and functionality added and broadcast-specific options stripped away. This is also where publishing to Facebook Live, YouTube Live and Twitter happens. After providing your live publishing credentials, Streambox manages the transcoding for the selected service. The publishing functionality does not prevent select users from establishing higher quality connections. You can have HQ streams to hardware and software decoders running simultaneously with a live streaming component.
The cloud effectively acts as a signal router to multiple destinations. Streamed content can be recorded and encrypted. Other cloud functionality includes realtime stitching of Ricoh Theta S camera outputs for 360º video.
Jonathan Abrams is Chief Technical Engineer at NYC’s Nutmeg Creative.