Add README

README.md

@@ -0,0 +1,39 @@
+# `inkpot-cli`
+
+This project contains the source code to the inkpot cli, a tool that can be used to convert JPEG, PNG and GIF images to 4-bit, 16-color grayscale images. The image format is designed to be simple to decode.
+
+## Usage
+
+```
+# inkpot help
+A command-line-tool that can be used to prepare images by
+resizing them, rotating them and converting them to 16-color
+grayscale so they can be comfortably displayed on e-ink
+displays powered by the epdiy driver.
+
+Usage:
+  inkpot-cli [command]
+
+Available Commands:
+  completion  Generate the autocompletion script for the specified shell
+  convert     Convert a single file to a 4-bit, 16-color grayscale image
+  help        Help about any command
+  serve       Run a webserver to convert images via HTTP
+
+Flags:
+  -h, --help   help for inkpot-cli
+
+Use "inkpot-cli [command] --help" for more information about a command.
+```
+
+## Development
+
+The package is written in [go](https://go.dev/) and you can use all the standard go tooling to run and build the binary. The individual commands are defined in the `cmd/` folder, the encoding / decoding bits are in `epd/`.
+
+If you are using the [nix package manager](https://nixos.org/), there is a description of the build and dev environment in `default.nix`, `shell.nix` and `flake.nix` / `flake.lock`. It is recommended to use [https://direnv.net/](direnv) with [flakes support](https://github.com/nix-community/nix-direnv#flakes-support).
+
+## Image Format (in progress)
+
+An image blob starts with a header containing ascii-encoded key-value pairs. It holds meta-information (such as an image's `width` `w` and `height` `h`), where case-insensitive keys are separated from values using a space and a colon character (`: `). A value ends with a newline character (`\n`). The end of the header data is marked by two consecutive newline characters (`\n\n`).
+
+The actual image data is following the header as a sequence of nibbles, or groups of four bits. Each nibble determines the grayscale value of a single pixel, where the first `w` nibbles designate the grayscale values of the first row of pixels (0 is black and 16 is white from left to right, the group of nibbles from `w + 1` to `2w` the second row of pixels from left to right and so on.

default.nix

@@ -14,9 +14,9 @@ buildGoModule rec {
   ldflags = "-linkmode external -extldflags -static";
 
   meta = with lib; {
-    description = "Command-line tool to customize Spotify client";
+    description = "Command-line tool to generate 4-bit grayscale images";
-    homepage = "https://github.com/khanhas/spicetify-cli/";
+    homepage = "https://github.com/saunaclub/inkpot-cli/";
     license = licenses.gpl3Plus;
-    maintainers = with maintainers; [ jonringer ];
+    maintainers = with maintainers; [];
   };
 }