Length, quiet weeks and filler

A film's target length is where it starts, not a promise. A month with three photographed days gets about 20 seconds, not a minute, and a quiet month with a week of nothing in it spends no shot on that week. When a film runs out of pictures worth showing, it ends early. A shorter film with every shot earned beats a full one padded with the fridge, the ceiling and a screenshot.

Taken to the end, a period can hold nothing worth a film at all: three pictures of a floor being laid, say. Then no film is made, the run says Nothing worth a film in February 2019 and exits 0. That is an answer, not a failure. But one shot worth showing is a film: a special day that keeps two good clips gets a 13-second film, not nothing. The only exception is on this day, which is about a day coming back, so it needs two years that hold something. A period with no pictures in it at all (a wrong date range, a filter, Immich unreachable) still ends in an error and exit 1.

How the target itself is set (per memory type, per active day, --duration) is on Memory types.

How long a shot is held

The constants live in analysis/editorial_structure_budget.py.

Shot	Hold
A still, no-model draft	4.0 s when starred or someone Immich knows is in it, 3.5 s otherwise
A still, model-planned film	4.0 s
A video	its length, up to 6.0 s; to the end of a sentence when someone is talking at the cut, never past 12 s from the start
A video under 2.0 s	not a shot at all
A Live Photo playing as motion	its clip, up to 6.0 s
A Live Photo playing as its still	4.0 s
The film's first and last still	+0.5 s, never past 5.0 s

Fitting the length

A film has more candidate shots than seconds, so two passes fit it.

The trim (trim_to_timing_budget, run after the draft and again once motion and speech are measured) drops whole shots, lightest story first: none and glimpse stories, then the extra shots of the lightest story, then its only shot, and the heaviest story's only shot last. Inside one story the latest shot goes first. A picture you ticked is never dropped, and a favourite is never dropped while a shot nothing vouches for (no star, no recorded video, nobody Immich knows, not ticked) is still in the film. In a film that gives every year a shot (a long person film, a custom film over several ranges), a year's only shot goes after every other one.

The shave takes 0.5 s off the longest hold, over and over, while the film is over length. It never takes a hold under 3.5 s (or under the shot's own length, if that was shorter) and never cuts through a sentence. A video is never dropped for being long.

Quiet weeks get no shot

On the no-model path, a happening with no indicator of its own reads as background, and background weighs none, which is 0 slots (GATE_WEIGHT and weight_caps, see Moments, episodes and stories). An indicator is any of: a favourite, a video, close family in it, a day four times busier than your median day, being away from home or outside your 12 usual cities, or being the only happening of a part the film must cover.

A week of ordinary evenings at home with no star, no video and no close family is exactly that case. Three favourites or a big close-family story still lift a story to major, so a quiet week that holds something you care about is never quiet to the editor.

Filler nothing vouches for

A quiet month can still have more slots than shots anyone vouches for, and the leftover slots go to whatever stands. So every film drafted from the rules gets one last removal pass (drop_filler_nothing_vouches_for, PR #1250), after the duplicate review:

Swipe sideways, or focus the diagram and use the arrow keys, to see more.

It runs on the no-model film and on a polished one alike. The polish refines the no-model film, so it never keeps what that film would drop: a caption that misreads a printed recipe as a posed child does not get it past this pass. A screen that plays as a Live Photo, or shows someone Immich knows, still stays. So does one shot of a year this pass would leave empty, in a film that gives every year a shot: the one that stands best. What left is listed by id and head label in derived-decisions/unvouched-filler.private.json.

An album handed over with a written subject (--from-album ... --subject ...) skips this pass. Every picture in it was picked for that subject, so a loaf in a bread film is the film, not filler (Picking each shot).

Going short, on purpose

The draft tries to reach its length before it gives up the seconds:

• Depth. When a story has slots left after every pass, it spends them inside the moments it already shows (editorial_story_depth.py): first moments no pick took, alternating between capture groups, then further frames of each chosen moment, one round at a time, until the slots run out. A 36-minute moment of laps on a track can fill a short film this way. Videos come before stills, frames are spread across the moment's time, and the story's place bound grows with the slots it now spends. Eligible favourites come first; equally preferred frames spread furthest in time from those already in. Every one must stand and must not look like its neighbours. A film of one repeated scene stays short.
• Readmission. A frame refused for looking like another, or for crowding its place, comes back when nothing else can fill the slot. A favourite refused for crowding its place comes back sooner. While the film has a free slot it takes that one and nobody leaves. Once the film is full, it comes back before a shot nothing vouches for keeps the slot it freed. That shot leaves (the weakest first, a story's only shot last, and never a year's only shot in a film that gives every year one) and is listed under displaced_for_a_favourite in derived-decisions/story-selection.private.json.
• With a model, a film still short by S seconds reads up to 2 × ceil(S / 3.5) episodes it never reached, and seats the ones whose reading records something (What a model adds).

What never happens: a slot filled with a frame nothing vouches for, a filler frame dropped by the pass above refilled, or a film padded with a still repeated for time. The final scene-duplicate check also accepts a shorter film: falling below the target's 15 % tolerance does not protect a repeated scene. Owner-required shots and someone's only family appearance keep their existing protections.

The run record says how it landed: near_target when the film is within 15 % of its content length, search_limited or editorial_shortfall when it ran shorter, with the seconds behind it.