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README.md

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+# menubg
+`menubg` is a tool for converting menu background images from AKI Corporation's
+wrestling games on Nintendo 64. It can also generate new background image files
+for use in the game.
+
+## Usage
+The program has two modes:
+1) Convert a list of binary files that make up a menu background into a PNG file.
+2) Convert a PNG file into binary files that make up a menu background.
+
+### Background Types
+It is important to note the menu background format changed between games.
+Properly converting data requires understanding the difference between the
+different background types.
+
+The "`old`" format is found in WWF WrestleMania 2000. It consists of ten
+slices, 320x24 pixels each.
+
+The "`new`" format is found in Virtual Pro-Wrestling 2 and WWF No Mercy.
+Each chunk is 64x30 pixels, and there are 40 chunks in total.
+
+### List Conversion
+`menubg -l LIST_FILE -t BG_TYPE [-d OUT_DIR]`
+
+where...
+- `LIST_FILE` is the path to a text file containing a list of files making up the menu background.
+- `BG_TYPE` is one of "`old`" or "`new`" (no quotes)
+- `OUT_DIR` is the optional output directory. The directory *must* already exist.
+
+### PNG to Menu Background
+`menubg -p PNG_FILE -t BG_TYPE [-d OUT_DIR]`
+
+where...
+- `PNG_FILE` is the PNG format file to convert to a menu background.
+- `BG_TYPE` is one of "`old`" or "`new`" (no quotes)
+- `OUT_DIR` is the optional output directory. The directory *must* already exist.
+
+The PNG file *must* be 320x240 pixels, and it *must* have a 16-color palette for
+conversion to work properly.
+
+## License
+This program is licensed under the Unlicense. See the `UNLICENSE` file for more information.
+
+This program uses LodePNG, which has a different license. Please see `lodepng.h` for more information.