This command line utility encodes and decodes arbitrary information in images.

The easiest way to install is through cargo

cargo install seagul

Passing data inline

seagul encode -d "Super secret message" path/to/source/image path/to/output/image

Getting data through STDIN

cat my_secret_file | seagul encode path/to/source/image path/to/output/image

Outputting to STDOUT (omit the target image)

seagul encode -d "Super secret message" path/to/source/image

The default channel used for encoding is the blue channel. To change it, use the --channel option.

seagul encode -d "Super secret message" --channel green path/to/source/image

For more encode options, see the integrated help with seagul encode --help

The decoder supports the same options as the encoder, with the addition of a --marker option to stop decoding when the specified byte sequence is found.

seagul decode path/to/image

# Stop at "end of sentence." sequence.
seagul decode --marker "end of sentence." path/to/image