TanStack

detectImageMimeType

Function: detectImageMimeType()

ts
function detectImageMimeType(base64Data): "image/png" | "image/jpeg" | "image/gif" | "image/webp" | undefined;

Defined in: packages/ai/src/utils.ts:17

Detect image mime type from base64 data using magic bytes. Returns undefined if the format cannot be detected.

This function analyzes the first few bytes of base64-encoded image data to determine the image format based on file signature (magic bytes).

Parameters

base64Data

string

The base64-encoded image data

Returns

"image/png" | "image/jpeg" | "image/gif" | "image/webp" | undefined

The detected mime type, or undefined if unrecognized

Example

ts
const mimeType = detectImageMimeType(imageBase64)
// Returns 'image/jpeg', 'image/png', 'image/gif', 'image/webp', or undefined