overcast-frame-grid

overcast-frame-grid

Use this skill to find roughly WHERE in a clip something appears with a single vision call, before spending per-frame calls. It's the "grid trick" from temporal-search research (frames tiled into one image; Set-of-Mark numbering over time). Pairs with overcast-pinpoint for the frame-precise follow-up. Use the broad overcast skill and overcast/reference/verbs.md for exact flags.

Workflow

overcast doctor --json
overcast case init --json
overcast grid ./clip.mp4 --count 16 --json     # -> media.grid: payload.montage + payload.cells + payload.cols
overcast see <montage-path> --prompt "Which numbered cells show <X>? Reply with cell numbers and why." --json

• If the grid record's payload.labeled is false (this ffmpeg build has no drawtext), tell see it's a <cols>-column grid numbered left-to-right, top-to-bottom (cols is in the record), so it can reference cells by position.
• Only the first count cells hold frames; the last row may be blank padding (those payload.cells[].at are null), so have see pick from 1..count and ignore blank tiles.
• Always map the chosen cell number back through payload.cells[n].at to get the real timestamp — never use a time the model typed out.

Zoom in on the winning region (narrow the window, or hand the timestamp to overcast-pinpoint):

overcast grid ./clip.mp4 --start <a> --end <b> --count 16 --json   # finer sheet around the hit
overcast see frame://<watch-record>@<t> --prompt "Is <X> here? yes/no + detail" --json
overcast note "<X> first visible" --ref <record> --at <t1-t2> --json
overcast brief --export ./grid-triage.md --json

Use --at "s1,s2,s3" instead of --count when you already have candidate timestamps to compare side by side; --start/--end to focus a window; --cols / --width to shape the sheet. Add --view (--no-open in a headless run) to also write a clickable HTML board — numbered, timestamped cells that seek the source clip — for eyeballing the sheet by hand; the montage PNG stays the input you hand to see.