What I learned cutting an hour of golf footage down to 40 seconds
A golf coach I work with records his lessons. His students want to see their swings. Those two facts are further apart than they sound.
A lesson recording is an hour long. Somewhere in it are maybe 【填:大概多少个】 swings, each a couple of seconds. The rest is setup, talking, walking to the next ball, and the camera pointing at nothing. Every evening he was scrubbing through footage with a timeline, dragging handles, exporting, renaming, sending. So he asked me whether that could just... not be his evening anymore.
The obvious problem wasn't the real one
I assumed the hard part would be detecting the swing. It wasn't 【填:一句话说你怎么做的检测——动作识别?姿态估计?声音?现成的库还是自己写的?】. That part worked early.
The hard part was that "a swing" isn't a moment, it's a judgment call. Where does the clip start — at address? When the club starts moving back? Two seconds before, so the student sees their own setup? And where does it end — impact, or after the follow-through settles, or when he starts talking about it?
I picked an answer, showed him, and was wrong 【填:他说了什么?他要更长的前摇还是更短的?】. That one round of feedback mattered more than anything technical I did.
What I'd tell someone building something similar
- The detection is a solved problem; the definition isn't. Spend your time with the person who'll use it, deciding what a "good clip" looks like to them.
- Show a rough version fast. He couldn't have told me the right clip length in the abstract. He could tell me instantly once he watched three of them.
- Err on the side of too many clips. Deleting an extra clip takes two seconds. A missed swing means going back into the hour of footage — which is the exact thing we were trying to get rid of.
- 【填:你自己踩的坑,哪怕很小】 —— 真实的小教训比漂亮话有用。
Where it ended up
He drops the recording in, and gets back a folder of swings, one file each 【填:跑一次大概多久?他现在怎么发给学生的?】. The editing evening is gone. Students get their swings the same day, while they still remember the lesson.
Nothing here was exotic. It was one annoying, repetitive job, looked at closely enough to notice that the annoying part wasn't where anyone assumed it was. That's most of what this work is.
Got a job like this — repetitive, obvious to you, nobody's ever automated it? Book a free 30-minute call. Happy to talk it through even if you don't hire me.