Prizegiving video from mixed phone footage
The school's media team is making a 90-second video for prizegiving, to be projected on the hall's 1920×1080 projector. Footage comes from three phones: 4K at 60 fps (two clips), 1080p at 30 fps (most clips), and two clips shot in portrait at 1080×1920. There is a 40-second interview recorded in a noisy corridor, and the team wants to use a popular song as background. Files total 14 GB on a 32 GB laptop with 6 GB free. The projectionist warns that the projector drops frames with 60 fps files. The team has one afternoon and one laptop; the song's artist is signed to a major label. The video must also work when posted on the school's website, where autoplay is muted and many viewers use phones.
1. Explain how the team should handle the mixed footage so the final video plays smoothly on the projector. Refer to at least two specific technical decisions.
Read the worked answer
Conform the timeline to one delivery format: 1920×1080, 30 fps, progressive, square pixels. Then make the technical decisions.
First, transcode the two 4K 60 fps clips down to 1080p30 before editing. That directly removes the projector's frame-drop problem, and it cuts file size on a laptop with only 6 GB free. Keeping 60 fps gains nothing on a 1080p30 projector. Second, treat the portrait clips separately: scale and crop them to 1080×1080 with a blurred fill either side, or pillarbox them against a background, rather than stretching them, which distorts faces.
Keep the 1080p30 clips as they are and set the sequence to 1080p30, so no clip is resampled twice. Export H.264 MP4 at 1080p30 with a bitrate around 10–12 Mbps, then test the exported file on the hall laptop before the event. A proxy workflow helps if editing stutters, but the conform step is the one that fixes playback.
2. The team wants the popular song but the video will be shown publicly and posted online. Recommend an approach and justify it.
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The song is on a major label, so recording it into a video that is shown publicly and posted online needs both a synchronisation licence for the composition and a master licence for the recording. Those are unlikely to be granted to a school in an afternoon, and 'it is for school' is not an exception.
The safer plan is to replace it with a track licensed for reuse: a Creative Commons track, checking whether it is CC BY, which requires attribution, or CC0, or a royalty-free library track with a written licence. Keep the credit line in the video and in the description. A school APRA licence may cover a live performance at prizegiving, but it does not cover recording the song into the video or uploading it.
If the team really wants the original song, they should request written permission well ahead, or use a student musician who signs a simple release. Choosing the replacement now protects the school, avoids a takedown, and keeps the deadline.
3. The corridor interview is noisy. Describe two fixes the team can make in the afternoon and explain which gives the best result for the effort.
Read the worked answer
Fix 1 is to re-record a voice-over in a quiet room, using the original audio only as a guide, or to record the interviewee again by phone in a quieter space. This is the best result for the effort because it removes the noise at the source; a 40-second re-record takes a few minutes and sounds natural if the speaker is available.
Fix 2 is to clean the existing audio: apply noise reduction, a high-pass filter around 80–100 Hz, and light compression, then lower the music under the voice. This is quick but noise reduction introduces artefacts if pushed hard, and voices can sound underwater.
A third fallback is to use captions or on-screen text for the key sentence and lower the interview level under narration, so the message survives even if the audio is imperfect. Choose fix 1 if the interviewee can be reached; otherwise use fix 2 conservatively, and do a final listen on phone speakers because that is how most of the website audience will hear it.