Safety Checker

Scan for hidden EXIF data, GPS coordinates, and steganography before sharing. Private & Secure

How it works

  1. 1

    The file is read as an ArrayBuffer. Its leading bytes are inspected against known magic byte signatures to verify the true MIME type.

  2. 2

    The byte stream is scanned for EXIF marker signatures: 0xFFE1 in JPEG and tEXt/eXIf chunk headers in PNG.

  3. 3

    The image is drawn onto a canvas and getImageData() extracts the raw RGBA values. The least-significant bit of each channel is isolated.

  4. 4

    Shannon entropy is computed on the LSB distribution. Values above 7.5 bits indicate near-random data, a statistical marker for steganography.

  5. 5

    Sanitization re-renders the image through a clean canvas pipeline. Only the visual pixel data is written to the output blob.

Tip

Re-rendering through a canvas is the only reliable sanitization method. It discards all bytes outside the raw pixel grid, including EXIF, XMP, and ICC profiles.