NAB Technology & Digital Tools 2 — Questions and Answers
Question 1: Which video codec is most commonly used for OTT (over-the-top) streaming delivery due to its high compression efficiency?
- H.264 (AVC)
- H.265 (HEVC) (Correct answer)
- MPEG-2
- ProRes 422
Correct answer: H.265 (HEVC)
H.265 (HEVC) offers approximately 50% better compression than H.264 at the same quality, making it the preferred codec for bandwidth-efficient OTT delivery.
Question 2: What does the acronym SDI stand for in broadcast infrastructure?
- Standard Digital Interface
- Serial Digital Interface (Correct answer)
- Synchronized Data Input
- Signal Distribution Index
Correct answer: Serial Digital Interface
SDI (Serial Digital Interface) is the professional broadcast standard for transmitting uncompressed digital video over coaxial cable.
Question 3: A broadcast engineer needs to measure loudness for compliance with CALM Act requirements. Which unit should they use?
- dBFS
- LKFS (Correct answer)
- VU
- SPL
Correct answer: LKFS
LKFS (Loudness, K-weighted, relative to Full Scale) is the measurement unit specified by the CALM Act and ITU-R BS.1770 for broadcast loudness normalization.
Question 4: In digital broadcasting, what is the purpose of a PCR (Program Clock Reference)?
- To encrypt the transport stream
- To synchronize the decoder's clock with the encoder (Correct answer)
- To measure signal-to-noise ratio
- To allocate bandwidth among programs
Correct answer: To synchronize the decoder's clock with the encoder
The PCR is embedded in MPEG-2 transport streams so that decoders can lock their local clock to the encoder's clock, ensuring proper audio/video synchronization.
Question 5: Which technology allows a broadcaster to insert targeted ads into a live stream for individual viewers?
- SCTE-35 with DAI (Correct answer)
- HLS chunked encoding
- RTMP ingest
- UDP multicast
Correct answer: SCTE-35 with DAI
SCTE-35 cue markers combined with Dynamic Ad Insertion (DAI) allow broadcasters to replace linear ad breaks with personalized ads for each viewer.
Question 6: What is the primary advantage of a software-defined broadcast infrastructure (SDBI) over traditional dedicated hardware?
- Higher raw signal quality
- Lower latency than all hardware solutions
- Flexibility to repurpose resources via software reconfiguration (Correct answer)
- Elimination of all licensing costs
Correct answer: Flexibility to repurpose resources via software reconfiguration
SDBI allows broadcast functions to run as software on commodity servers, enabling rapid reconfiguration and scaling without purchasing new dedicated hardware.
Question 7: In an IP broadcast facility using SMPTE ST 2110, which sub-standard governs the transport of uncompressed video?
- ST 2110-10
- ST 2110-20 (Correct answer)
- ST 2110-30
- ST 2110-40
Correct answer: ST 2110-20
SMPTE ST 2110-20 specifies the transport of uncompressed active video essence over IP networks using RTP.
NAB Technology & Digital Tools 2
Which video codec is most commonly used for OTT (over-the-top) streaming delivery due to its high compression efficiency?