remotion-dev/remotion · error · TypeError

Cannot interpolate " " as because it is a transform-origin…

Error message

Cannot interpolate "${output}" as ${outputType} because it is a transform-origin value

What it means

interpolate() infers the transform kind (scale, translate, rotate, etc.) of string output values; all outputs must be the same kind and match the declared outputType. When the inferred kind differs from outputType, a TypeError is thrown because values of different transform kinds cannot be interpolated together.

Solutions

1. Correct outputType to match the actual output values (e.g. 'translate' for px values).
2. Make all output range values the same transform kind.
3. Remove outputType and let interpolation infer, or split into separate interpolations.

Example fix

// before
interpolate(f, [0,1], ['0px','100px'], {outputType: 'scale'})
// after
interpolate(f, [0,1], ['0px','100px'], {outputType: 'translate'})

const kinds = outputs.map(inferKind); // e.g. px->translate, unitless->scale
if (new Set(kinds).size > 1) throw new Error('mixed transform kinds');

try {
  interpolate(f, r, vals, {outputType});
} catch (e) {
  if (e instanceof TypeError) normalizeOutputRange();
}

When it happens

Trigger: interpolate called with string outputs like '10px' (translate) or '1.5' (scale) plus an outputType that doesn't match the inferred kind; mixing kinds across the output range triggers a sibling error and mismatched outputType triggers this one.

Common situations: Passing 'translate' values with outputType: 'scale'; refactoring animations and leaving a stale outputType; mixing '10px' and '50%' values in one range.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

• bezier x values must be in [0, 1] range
• Cannot interpolate " " as because it is a rotate value
• A "duration" of a spring is NaN, which it must not be
• A "duration" of a spring must be a "number" but is
• A "duration" of a spring must be finite, but is

AI-assisted analysis of remotion-dev/remotion@46a3a6bf13 (2026-09-18). Data as JSON: /api/errors/2ed99ab5613606d6. Report an issue: GitHub.

Appendix: source

Thrown at packages/core/src/interpolate.ts:500

		}

		return parseTransformOriginValue(output, parts);
	}

	const parsed = parts.map((part) =>
		parseStringInterpolationComponent(part, output),
	);
	const [{kind}] = parsed;
	for (const part of parsed) {
		if (part.kind !== kind) {
			throw new TypeError(
				`Cannot interpolate "${output}" because it mixes ${kind} and ${part.kind} values`,
			);
		}
	}

	if (outputType !== undefined && outputType !== kind) {
		throw new TypeError(
			`Cannot interpolate "${output}" as ${outputType} because it is a ${kind} value`,
		);
	}

	if (kind === 'scale') {
		const x = parsed[0].value;
		const y = parsed[1]?.value ?? x;
		const z = parsed[2]?.value ?? 1;
		return {
			kind,
			values: [x, y, z, 0],
			units: [null, null, null, null],
			dimensions: parsed.length,
			axisRotation: false,
		};
	}

	return {

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