zoom_in

Apply a linear zoom-in effect to a Video.

Call shape

zoom_in(video: Video, by?: Number) -> Video

This is call-shape notation for lookup, not ClipAsm declaration syntax.

Graph inputs

Parameters and defaults

Result and stack behavior

Outputs: Video.

Default stack access is owned. See stack binding for ownership and visibility rules.

Timeline and markers

The program keeps the duration and addressable markers from video.

Example

clipasm 1

config {
    video {
        fps = 30
    }
}

image("assets/card.png", 2s)
zoom_in(12%)

Expected validation result: Video with exactly 60 project frames at the example’s explicit fps = 30.

The reference checks parse and compile this exact example. Compilation does not inspect the named media files.

Behavior

• For a multi-frame Video, scale increases linearly from 100% on the first frame to exactly 100% + by on the last frame.
• Directly adjacent zoom_in calls are composed into one perspective resampling pass; their per-frame scale curves multiply in authored order.
• The program preserves the Video timeline and the attached meaningful-Audio state.

Requirements

• by must be positive.
• Adjacent zooms must fit the 24 KiB composed-filter limit.

Common diagnostics

These are the diagnostics most specific to this program.

• E_INVALID_ZOOM_AMOUNT — Invalid zoom amount
• E_GRAPH_TOO_LARGE — Graph size limit exceeded

See also

• Statements and calls
• Stack binding