Ultra HD Contribution

Live sporting events or concerts really benefit from being produced in Ultra HD with fantastic resolution and with frame rates of 50/60fps allowing the action to be captured without motion blur. Delivering the content back to the studio requires that the video is compressed in some way. To allow the content to be processed back at base a 4:2:2 feed is essential. Xylostream have introduced the world’s first 4:2:2 12-bit contribution solution based on the Excel 4000 encoder coupled with the Xylostream XD4000 professional Ultra HD decoders. This unique solution now makes it possible to use HEVC as the compression codec providing higher picture quality for the available bandwidth.

Features / Benefits

The ‘gang of four’ approach just doesn’t work

To date the approach that has been taken for contribution or distribution of Ultra HD has typically been to divide the picture into 4 quadrants and use 4 x H.264 HD encoders. Typical bitrates have had to remain high, over 100 Mbit/s, to allow for extra bandwidth to be used to try to mask the picture joins. This approach has been fraught with difficulties as the quadrants fall out of sync and the joins in the middle of the picture are hard to eradicate completely even with high bit rates. The approach is also costly as gangs of 4 encoders and 4 decoders are required, as well as extra synchronisation equipment.

HEVC is ready for live event contribution

With the availability of real time HEVC encoders and professional HEVC decoders it is now possible to turn to HEVC for live event contribution. The HEVC approach delivers significant bit rate savings versus the 4 by HD H.264 approach, bit rates are typically halved for the same picture quality without the risk of picture joins destroying the image. Using a hardware based encoder also delivers low latency, an essential feature for any contribution solution.

The Xylostream Excel 4000 is ideal for contribution encoding

The Excel 4000 now with 4:2:2, 12-bit support, is ideally suited for the contribution application as it is based on Xylostream’s compression engine - a set of innovative, proprietary HEVC algorithms - running on an FPGA-accelerated High Performance Computer. As such the hardware accelerated platform provides very low latency encoding. In addition, the Excel 4000 is capable of sustaining bit rates up to 80Mbit/s allowing for the highest quality contribution feeds.

The Xylostream XD4000 professional decoder completes the chain

Compressed video contribution feeds need to be decoded and then presented to the playout chain over 4x3G-SDI. The XD4000 provides the final link in the contribution chain allowing the contributed video to be presented over standard interfaces. As the XD4000 uses a unique hardware decoder latency is also minimised. The unit also supports up to 12-bit colour depth and bit rates up to 80Mbit/s as a match for the Xylostream Excel 4000 encoder.