Preparation of warm inputs for digital content streaming

Systems and methods, to efficiently prepare for live and stored file content, implement one or more warm inputs, which actively ingest and demux content, but do not actively decode the content until an input switch is commanded. Each warm input can cache a most recent instantaneous decoder refresh and subsequent reference frames (I-frames and P-frames). Upon an input switch being commanded, the subject input commences decoding of such preserved frames. The formerly-warm input then acts as a hot input (decoding every frame) until the input switch completes. The use of warm inputs, which avoid the decoding stage, reduces computational resource use, allows preparation of all inputs by default, and permits metrics, status reports, and thumbnails to be generated regarding non-active inputs.