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Replaces the rigid `--fps 24|30|60` whitelist with a numeric range and
adds support for ffmpeg-style fractional framerates so NTSC stays exact
end-to-end.
- `--fps 30` keeps working (integer fps)
- `--fps 30000/1001` now means exact NTSC 29.97 (not the lossy decimal)
- `--fps 24000/1001`, `--fps 60000/1001`, `--fps 25/50/120/240` all work
- Decimals like `--fps 29.97` are rejected with a friendly error pointing
the user at the rational form, since `29.97` and `30000/1001` round
to different framerates inside ffmpeg
Carries an `Fps = { num: number; den: number }` rational end-to-end:
RenderConfig, EncoderOptions, StreamingEncoderOptions, CaptureOptions,
DockerRenderOptions, Studio API request body, regression-harness
meta.json. The `-r` and `-framerate` ffmpeg args emit the rational form
verbatim (`30000/1001`) so no decimal round-trip happens at the encoder
boundary. Frame-interval math uses `1000 * den / num` ms (33.366… for
NTSC, 33.333… for integer 30).
Helpers live in @hyperframes/core:
- `parseFps(input: string | number): FpsParseResult` — discriminated
parser used by both the CLI and the Studio API route
- `fpsToFfmpegArg(fps: Fps): string` — emits "30" or "30000/1001"
- `fpsToNumber(fps: Fps): number` — for arithmetic (telemetry, frame
count, frame-index → time)
Studio API wire format accepts polymorphic `fps: number | string`:
- number → integer fps (`30`)
- string → rational (`"30000/1001"`)
Decimals are rejected; matches the same rule as the CLI.
Existing meta.json fixtures with integer `"fps": 30` continue to load
unchanged — the regression-harness validator now normalizes both number
and string inputs through `parseFps`.