Multimedia, Digital Media and Emerging Broadcast Technologies
This domain checks that you can name today's delivery chain and use its units correctly: codecs versus containers, streaming protocols versus file transfer, and resolution versus dynamic range. Many candidates lose marks by using "HD" and "high quality" as if they were measurements.
Multimedia and delivery
- Multimedia combines text, graphics, audio, video, animation and interactivity; web and mobile delivery demands adaptive formats and accessible captions.
- Analogue switch-off moved terrestrial broadcasting to digital standards such as DVB-T2, ATSC and ISDB, alongside DTH satellite, cable and IPTV.
- Streaming uses HLS or MPEG-DASH with adaptive bitrate over a CDN; RTMP is used for ingest from encoder to server; latency differs between live streaming, video on demand and broadcast.
Compression and containers
- Codecs: H.264/AVC, H.265/HEVC, AV1, VP9, and mezzanine formats ProRes or DNxHD for editing.
- Containers: MP4, MOV, MXF, MKV. A container wraps video, audio and metadata; it is not a codec.
- Bitrate and resolution drive file size; higher efficiency codecs deliver equal quality at lower bitrate.
Emerging technology
- 4K UHD is 3840 × 2160; 8K is 7680 × 4320; HDR uses PQ or HLG transfer functions with Rec.2020 wide colour gamut.
- Immersive audio, VR and AR/XR, IP-based production (SMPTE ST 2110, NDI), cloud editing, AI-assisted transcription and OTT platforms all change workflow rather than the fundamentals.
Worked example. A 60 s 4K clip at 100 Mbps: 100 Mbit/s × 60 s = 6000 Mbit; divide by 8 = 750 MB. Reasoning shown separates megabits from megabytes, the commonest arithmetic error in this domain.
Traps
- Calling MP4 a codec; it is a container.
- Confusing HDR with higher resolution; HDR is dynamic range and colour volume.
- Mixing DCI 4K (4096 × 2160) with UHD (3840 × 2160).
- Forgetting the Mbit to MB division by 8 in file-size questions.