* fix(core): preview audio fades play as ramps on the audio clock, so cuts no longer click data-fade-in / data-fade-out were folded into one volume per 50 ms sync tick and applied as a step (el.volume, or gain.value in the Web Audio transport), so a 20 ms fade never played and each clip started and stopped at near full level: a click at every cut. The export applies the fades (ffmpeg afade) and does not click. The transport now books each clip's fades on a gain of its own when it schedules the clip, for both decoded buffers and captured media elements: a linear ramp from where the clip starts sounding up to its fade-in, and down to silence at its end. The sync tick hands the transport the level without the fade (onElementVolume's new fifth argument, sent only where a fade applies), so a booked fade is not applied twice. The plain el.volume fallback keeps its stepped fade. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(core): one doc block on setElementVolume Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(core): keep the comment share where it was Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(core): booked fades hold through pre-roll, follow rate changes, skip unbounded ends Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * chore: raise the producer unpacked budget to the measured size plus 1% Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
@hyperframes/core
Types, parsers, generators, compiler, linter, runtime, and frame adapters for the Hyperframes video framework.
Install
npm install @hyperframes/core
Most users don't need to install core directly — the CLI, producer, and studio packages depend on it internally.
What's inside
| Module | Description |
|---|---|
| Types | TimelineElement, CompositionSpec, Asset, canvas dimensions, defaults |
| Parsers | parseHtml — extract timeline elements from HTML; parseGsapScript — parse GSAP animations |
| Generators | generateHyperframesHtml — produce valid Hyperframes HTML from a composition spec |
| Compiler | compileTimingAttrs — resolve data-start / data-duration into absolute times |
| Linter | lintHyperframeHtml — validate Hyperframes HTML (missing attributes, overlapping tracks, etc.) |
| Runtime | IIFE script injected into the browser — manages seek, media playback, and the window.__hf protocol |
| Frame Adapters | Pluggable animation drivers (GSAP, Lottie, CSS, or custom) |
Generated composition trust
Composition generators require trusted authors for code-bearing inputs. styles and
generateHyperframesStyles preserve authored CSS, which can load external resources.
animations may contain __raw: values that are emitted as JavaScript;
includeScripts: true includes executable timeline code. serializeGsapAnimations
also accepts raw preamble, postamble, and a code-bearing timelineVar. Never fill
these inputs with untrusted data. Attribute encoding and closing-tag containment
are not a sandbox; render untrusted compositions in an appropriately isolated
execution environment and never serve them on a privileged origin.
Text content retains the supported inline-formatting sanitizer contract. The clip parser intentionally flattens inner formatting to text, so parse/generate is not a lossless replacement for editing the source HTML.
Frame Adapters
A frame adapter tells the engine how to seek your animation to a specific frame:
import { createGSAPFrameAdapter } from "@hyperframes/core";
const adapter = createGSAPFrameAdapter({
getTimeline: () => gsap.timeline(),
compositionId: "my-video",
});
Implement FrameAdapter for custom animation runtimes:
import type { FrameAdapter } from "@hyperframes/core";
const myAdapter: FrameAdapter = {
id: "my-adapter",
getDurationFrames: () => 300,
seekFrame: (frame) => {
/* seek your animation */
},
};
Parsing and generating HTML
import { parseHtml, generateHyperframesHtml } from "@hyperframes/core";
const { elements, metadata } = parseHtml(htmlString);
const html = generateHyperframesHtml(spec);
Linting
import { lintHyperframeHtml } from "@hyperframes/core/lint";
const result = lintHyperframeHtml(htmlString);
// result.findings: { severity, message, elementId }[]
Documentation
Full documentation: hyperframes.heygen.com/packages/core
Related packages
@hyperframes/engine— rendering engine that drives the browser@hyperframes/producer— full render pipeline (capture + encode)hyperframes— CLI