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Currently, MPEG-2 transport streams are still best for contribution when implementing a hybrid FMV streaming architecture. They provide predictable real-time performance from existing sensor systems from air-to-ground, air-to- cloud, or ground-to-cloud scenarios. To improve picture quality and reduce bit rate, HEVC/H.265 video compression should be considered as the video contribution format. For distribution of FMV streams, OTT streaming formats, such as HTTP Live Streaming (HLS), Dynamic Adaptive Streaming over HTTP (DASH), or Common Media Application Format (CMAF) are best. They offer ABR profiles, allowing the same live stream to be encoded at single or multiple renditions, from high quality, higher bit rate to low quality, lower bit rate. 2. IMPROVE QUALITY OF EXPERIENCE Live video contribution over RF transmission systems are vulnerable to packet loss if not provisioned for error recovery. Dropped packets equate to data loss, which degrades the quality of experience at the client side decoder. Poor quality of experience (QoE) could be in the form of video pixelation, choppy playback, artefacts, or freeze frames. While wireless RF transmission systems can be rapidly deployed in tactical environments, they can exhibit unpredictable behaviours when pushed to their limits. Though by nature of the protocol, UDP/ IP flows are unreliable, they are heavily deployed in mission systems. Toggling these flows to real-time transport protocol (RTP) can improve stream resiliency. RTP was designed for real-time transfer of audio/video information over IP networks and includes several techniques that can better facilitate media-based delivery systems including timestamps, sequence numbers and payload types, which can be helpful in addressing common issues such as late or out-of-order packets. There are many ways to measure the general health and performance of a network. One practice is the basic ”ping” test, which uses a combination of ICMP control messages (Echo Request and Echo Reply) to measure specific conditions such as packet loss, latency and throughput between a source and destination. Ping is a common command line utility found on most operating systems and
MISSION POSSIBLE As OTT and streaming technologies improve, mission video systems are being transformed
comes into play. Full motion video streams generally contain geospatial metadata found in a data encoding standard known as KLV (Key-Length-Value). The underlying metadata contains specific location information about the video from the camera sensor or aircraft perspective (eg latitude, longitude, altitude, etc.). From a distribution standpoint, FMV streams are transformed from MPEG- 2 transport stream encapsulation to newer adaptive streaming formats, such as MPEG-DASH and HLS. Since these streaming protocols were designed to serve media and entertainment content over the internet, there was not a well-documented methodology to carry KLV information in the consumer market as there was with MPEG-2 transport streams. However, if KLV metadata were filtered out or lost in translation, FMV content would be less useful to an analyst, providing the most basic situational awareness without the descriptive geospatial data required for processing, exploitation and dissemination workflows. To overcome this obstacle and preserve the mission-oriented KLV metadata in an FMV streaming environment, AWS Elemental implemented the carriage of KLV in the fMP4 containers capable of facilitating many mainstream ABR formats in use today. Mission video systems are undergoing an evolution, as OTT and streaming developments open new opportunities for government
UNTIL RECENTLY, MOST GOVERNMENT VIDEO SYSTEMS MIRRORED LEGACY COMMERCIAL BROADCAST AND IPTV DESIGNS can provide good metrics about network conditions. Other forms of contribution encoding, such as ground-to-cloud, may be better off using more advanced packet protection methods that can guarantee media delivery. During Enterprise Challenge, the ground-based system terminated the aircraft RTP-FEC flow, then re-encapsulated it as a ground-to-cloud flow using reliable transport technology from Zixi. The Zixi transport protocol provides added network resiliency through a combination of applied FEC and ARQ (Automatic Repeat Request) for advanced error-recovery. It is offered on the AWS Elemental MediaConnect service using ground and cloud-based link components for secure, reliable live video transport. 3. CARRYING METADATA OVER ABR Video provides situational awareness, but doesn’t offer insight as to where activity took place, which is where metadata
agencies to access, review and analyse video from the field like never before.
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