Projects / Enscribe


Enscribe creates digital audio watermark images. The rasterlines of an image are converted into frequency components via an inverse fast fourier transform. The watermarks sound like soft hissing, but when viewed in a frequency-versus-time display, the image is clearly visible. Manipulation of the audio file, such as by MP3/Ogg compression, reverb, or flange, muddies the image, but it remains visible.

Operating Systems

Recent releases

  •  19 Jun 2008 03:51

    Release Notes: The -length option was added to specify the numer of seconds of output. The -mask option was added to use an external sound file as a convolution mask.

    •  14 Sep 2004 18:47

      Release Notes: The monaural / color sanity check has been fixed. Oversampling has been changed to 4X to get rid of the last of the buzzing. Oversampling is still done only when the -o or -oversample flag is used. Lost frames at the end of a sound file when using -oversample has been fixed.

      •  05 Jul 2004 16:09

        Release Notes: PNG loading was fixed. Endian-ness bugs were fixed. AIFF and AU support were added. The ability to pipe raw audio to STDOUT was added. Third color channel emulation based upon Bauline's -monet switch was added. The -hiss option was added to create softer sound files by using random phases for each iFFT pass. Hissed images are quieter and more resistant to digital mangling. Enscribe now requires libsndfile.

        •  27 Jun 2004 20:41

          Release Notes: This release supports JPEG, PNG, WBMP, Xbm, and GD images. It can also output wav files in addition to raw audio data. Oversampling, start and stop frequencies, new color conversion modes, windowing, and some minor bugfixes are included in this new version.

          •  24 Jun 2004 15:29

            No changes have been submitted for this release.


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