Oversubscription of Decoder Channels

Oversubscription occurs when the sum of the streams being decoded exceeds the capabilities of the decoder. This can be due to bitrate (aggregate bitrate ingress limit) or resolution/frame-rate (limit is 1 x UHDp60 or equivalent). This topic explains the behavior of the decoder when streams are sent that overtax its capabilities.

The Makito X4 decoder can decode up to a single 3840x2160p60 stream. This represents 100% of the system’s decoding capacity.

The video decoding resources are prioritized with the lower decoder numbers having higher priority, i.e.:

• Decoder 0 has highest priority

• Decoder 1 has 2nd highest priority

• Decoder 2 has 3rd highest priority

• Decoder 3 has lowest priority

This priority logic is only exercised if one of the active streams is UHD, because the Makito X4 can decode up to four 1920x1080p60 streams simultaneously without difficulty.

Oversubscription occurs when more than one 3840x2160p60 stream or more than two 3840x2160p30 streams are decoded. In this situation, Decoder 0 will always run, and Decoder 1 will run if there are enough resources remaining, then Decoder 2, then Decoder 3.

Important

Any streams that are mission-critical and cannot be interrupted should always be decoded on Decoder 0. The lower-priority decoders that are running may be interrupted during decoding if the video decoding resources are required for a higher-priority decoder.