pelya

As long as your byte consists of 8 bits.

Saving arbitrary metadata is the exact use case for pickle module, you just put it together with your numpy array into a tuple. jpeg format has support for storing metadata, but they are an afterthought like .mp3 tags, half of applications do not support them.

I can imagine multichannel jpeg to be used in photo editing software, so you can effortlessly create false-color plots of your infrared data, maybe even apply a beauty filter to your Eagle Nebula microwave scans.

What, pickle.dump your enormous Numpy array not good enough for you anymore? Not even fancy zlib.compress(pickle.dumps(enormousNumpyArray)) will satisfy you? Are you a scientist or a spectral data photographer?

1. Type letter ‘c’ using the text tool, as you’ve already done
2. Create a new layer from text
3. Duplicate layer
4. Transform - flip horizontally
5. Merge two layers

It’s a basic GIMP knowledge, really. Don’t forget to add an alpha channel to your layer after step 2, otherwise it won’t work.