A green render proves nothing
The render succeeding means the code ran. It says nothing about whether a word is clipped, a scene opens on an empty frame, or a click fires before the sentence finishes typing.
Sample densely enough
- Sampling at 1fps missed seven real defects on a 55 second film. At 3fps all seven showed up
- Extract frames and look at them as a contact sheet:
ffmpeg -i out.mp4 -vf fps=3 frames/%04d.png - What that pass caught, none of which a build would flag:
- a send button clicked before the sentence had finished typing
- two scenes opening on an empty frame, because the entry animation started at zero opacity with no hold
- a spark scaled past the frame, so only its concave edges were visible and it read as a smear
- a word clipped mid-letter from a stale text measurement
- Check the first and last frame of every scene specifically. That is where entry and exit animations fail
Facts on screen
- Do not invent figures. A first cut carried four invented costs, which had to be replaced with real ones from published sources
- Record for every number: the URL, the exact wording on the source, and the date you read it. Put that table next to the code, not in a commit message
- Watch what the number is attached to. One figure was accurate but sat under the wrong label, because the source quoted it for a narrower item than the caption claimed. The number being right is not enough
- Re-read anything that moves, like a salary average, before every re-render, and update every scene that cites it in the same change
- Put the attribution on screen
Captions
- A film with no speech still needs a caption track. Describe the on-screen copy and what is happening, in step with the cuts
- Derive the timings from the scene lengths in the running order, so they cannot drift from the edit