Read the text out of a QR code or barcode in a PNG or JPEG image. Auto-detects QR, DataMatrix, PDF417, Aztec and 1D symbologies (Code128/39/93, EAN-13/8, UPC-A/E, ITF, Codabar). A valid image with no code returns { found: false }; a payload that is not a parseable image is a 400.