add ffmpeg support (#753)

* add ffmpeg support

* add image quality options

source/_components/camera.ffmpeg.markdown

@@ -0,0 +1,42 @@
+---
+layout: page
+title: "FFmpeg Camera"
+description: "Instructions how to integrate a Video feet with FFmpeg as cameras within Home Assistant."
+date: 2015-09-17 08:01
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: ffmpeg.png
+ha_category: Camera
+---
+
+
+The `ffmpeg` platform allows you to use every video feet with [FFmpeg](http://www.ffmpeg.org/) as camera in Home Assistant.
+
+<p class='note'>
+You need a ffmpeg binary in your system path. On debain 8 you can install it from backports. If you want HW support on raspberry you need self build from source. Windows binary are avilable on ffmpeg homepage.
+</p>
+
+To enable your Foscam IP camera in your installation, add the following to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+camera:
+  platform: ffmpeg
+  input: FFMPEG_SUPPORTED_INPUT
+  name: FFmpeg
+  ffmpeg_bin: /usr/bin/ffmpeg
+  extra_arguments: -q:v 2
+```
+
+Configuration variables:
+
+- **input** (*Required*): A ffmpeg compatible input file, stream or feet.
+- **name** (*Optional*): This parameter allows you to override the name of your camera.
+- **ffmpeg_bin** (*Optional*): Default 'ffmpeg'.
+- **extra_arguments** (*Optional*): Extra option they will pass to ffmpeg. i.e. image quality or video filter options.
+
+Image quality:
+
+You can controll the image quality with [extra_arguments](https://www.ffmpeg.org/ffmpeg-codecs.html#jpeg2000) *-q:v 2-32* or with lossless option *-pred 1*.