Added basic readme

README.md

@@ -1,2 +1,19 @@
-# sstv
 SSTV Decoder
+============
+
+A slow-scan television decoder that works on audio files rather than a soundcard (like most other decoders).
+Currently supports the following modes:
+* Martin 1
+* Scottie 1
+* Robot 36
+
+Installation
+------------
+
+`git clone https://github.com/colaclanth/sstv.git`
+`python setup.py install`
+
+Usage
+-----
+
+`sstv -d audio_file.wav -o result.png`