More on README

README.rst

@@ -9,3 +9,52 @@ A captcha library that generates audio and image CAPTCHAs.
    :target: https://ci.appveyor.com/project/lepture/captcha
 .. image:: https://coveralls.io/repos/lepture/captcha/badge.png?branch=master
    :target: https://coveralls.io/r/lepture/captcha
+
+
+Features
+--------
+
+1. Audio CAPTCHAs
+2. Image CAPTCHAs
+
+Installation
+------------
+
+Install captcha with pip::
+
+    $ pip install captcha
+
+Usage
+-----
+
+Audio and Image CAPTCHAs are in seprated modules::
+
+    from io import BytesIO
+    from captcha.audio import AudioCaptcha
+    from captcha.image import ImageCaptcha
+
+    audio = AudioCaptcha(voicedir='/path/to/voices')
+    image = ImageCaptcha(fonts=['/path/A.ttf', '/path/B.ttf'])
+
+    data = audio.generate('1234')
+    assert isinstance(data, bytearray)
+    audio.write('1234', 'out.wav')
+
+    data = image.generate('1234')
+    assert isinstance(data, BytesIO)
+    image.write('1234', 'out.png')
+
+This is the APIs for your daily works. We do have built-in voice data and font
+data. But it is suggested that you use your own voice and font data.
+
+
+Contribution
+------------
+
+We need voice wav files. The voice wav file should be in 8-bit, please keep it
+as small as possible. Name your voice file as::
+
+    {{language}}-{{character}}-{{username}}.wav
+    # exmaple: zh-1-lepture.wav
+
+TODO: we need a place to upload voice files.