docs: Document processing AAXC files

README.md

@@ -1,5 +1,5 @@
 # aax-to-mp3
-Simple dockerized Node.js web service for converting an AAX file into an MP3 file.
+Simple dockerized Node.js web service for converting an AAX (or AAXC) file into an MP3 file.
 
 ## Usage
 Install [Docker](https://www.docker.com/), then run:
@@ -10,16 +10,34 @@ Then fire up http://localhost:80/ in your browser.
 
 ![Usage example](https://user-images.githubusercontent.com/837775/204081687-34001d41-1c44-4e06-82e2-ecf4cb095586.png)
 
-Select your AAX file and click `Convert`. The whole conversion should take 5-10 minutes.
+### Convert AAX
 
-The MP3 file will be downloaded when processing is complete.
+Click the upload button, select your `.aax` file, and click `Convert`. The whole conversion should take 5-10 minutes, depending on how large your file is.
+
+An MP3 file named `audiobook.mp3` will be downloaded when processing is complete.
+
+### Convert AAXC
+
+If you are trying to convert a AAXC file, you need to upload three extra files related to your audiobook.
+The files will be named something like this:
+
+* `example-AAX_22_64.aaxc`
+* `example-AAX_22_64.voucher`
+* `example-chapters.json`
+* `example_(1215).jpg`
+
+Click the upload button, select all four files (using the **Ctrl** or **Command** key), and click `Convert`.
+
+![image](https://user-images.githubusercontent.com/837775/214339109-388f75f7-fba8-4517-ae8b-79c2d9e291aa.png)
+
+If your filename of your AAXC file does not end with the `.aaxc` file extension, rename it.
 
 ## Manual installation
 Install [Docker](https://www.docker.com/), then build the image yourself:
 ```
 $ git clone git@github.com:Sebelino/aax-to-mp3
-$ cd aax-to-mp3
-$ docker build -t sebelino/aax-to-mp3 .
+$ cd aax-to-mp3/
+$ docker build -t sebelino/aax-to-mp3:dev .
 ```
 
 ## Notes