Update README.md

Author: nobu-k

README.md

@@ -1,22 +1,27 @@
 [![wercker status](https://app.wercker.com/status/4db748e2b586121e924f83ef991a5f7b/s "wercker status")](https://app.wercker.com/project/bykey/4db748e2b586121e924f83ef991a5f7b)
 
-# OpenCV plug-in for SensorBee
+# OpenCV plugin for SensorBee
 
-This plug-in is a library to use [OpenCV](http://opencv.org) library, User can use a part of OpenCV functions. For example user can create source component to generate stream video capturing.
+This is the [OpenCV](http://opencv.org) plugin for SensorBee.
 
-# Require
+This plugin currently supports following features of OpenCV:
 
-* OpenCV
-    * attention that ffmpeg version.
-    * ex) Mac OS X `brew install opencv --with-ffmpeg`
+* Inputting video stream from a file or a camera
+* Encoding JPEG
+* Cascade classifier
+
+# Requirements
+
+* OpenCV with ffmpeg enabled for video input sources
+    * Example on Mac OS X: `brew install homebrew/science/opencv --with-ffmpeg`
 * SensorBee
-    * later v0.5
+    * v0.5 or later
 
 # Usage
 
-## Registering plug-in
+## Plugin Registration
 
-`build_sensorbee` with build.yaml set `gopkg.in/sensorbee/opencv.v0/plugin`
+Add `gopkg.in/sensorbee/opencv.v0/plugin` to build.yaml for the `build_sensorbee` command.
 
 ### build.yaml
 
@@ -25,9 +30,9 @@ plugins:
 - gopkg.in/sensorbee/opencv.v0/plugin
 ```
 
-## Using from BQLs sample
+## BQL examples
 
-### Capturing video source and streaming frames
+### Capturing frames from a video file
 
 ```sql
 -- capturing
@@ -36,8 +41,11 @@ CREATE PAUSED SOURCE camera1_avi TYPE opencv_capture_from_uri WITH
     frame_skip=4, next_frame_error=false;
 ```
 
-will start generating stream from "video/camera1.avi" after execute `RESUME` query.
+This source will start generating a stream from "video/camera1.avi" after executing `RESUME` query.
 
 ```
 RESUME SOURCE camera1_avi;
 ```
+
+Note that `PAUSED` should not be specified when capturing from a webcam, which
+keeps generating a video stream.