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@@ -1,12 +1,18 @@
 # slide
-Simple slideshow showing random images from specified directory
+Simple slideshow showing random images from specified directory.
+Screen background is filled with a scaled version of the image to prevent pure black background.
 
 ## Usage
 
 ```
-slide /path/to/images
+slide [-t rotation_seconds] [-o background_opacity(0..255)] [-b blur_radius] -p image_folder
 ```
 
+* `image_folder`: where to search for images (.jpg files), currently non-recursively
+* `rotation_seconds(default=30)`: time until next random image is chosen from the given folder
+* `background_opacity(default=150)`: opacity of the background filling image between 0 (black background) and 255
+* `blur_radius(default=20)`: blur radius of the background filling image
+
 ## Dependencies
 
 * libexif