PNG Filter Steganography

Decode

Select a file:

Raw filter bytes:

Decoded output:

Encode

Select a file:

Enter payload to encode:

Payload length:

Encode/Download

Description:

Encode/Decode either an arbitary file or text payload into a PNG by editing the filter bytes. A longer image will have more capacity than a shorter one. Any PNG input is supported but will be saved as RGBA. Also note that due to alpha premultiplication the RGB values of a 0 alpha pixel are lost