Clean a Signature Image Background
Clean a signature scan on white paper with an adjustable brightness threshold. Keep processing local and check faint strokes before using the image.
Clean a scan without erasing the strokes
Use a well-lit scan or photo of a signature on plain white paper. Adjust the white threshold gradually. Pixels at or above the threshold become white; darker pixels are darkened to emphasise the strokes.
Worked example and checks
Start around 170 and compare the result with the original at full size. A lower threshold whitens more pixels and can erase faint ink. A higher threshold retains more shading and paper texture. Crop excess paper before processing for a cleaner result.
Is this a digital signature?
No. This tool prepares an image of an existing signature. It does not authenticate identity, create a certificate or digitally sign a PDF. Use only a signature you are authorised to reproduce.