documentation, performance, usage

.gitignore

@@ -0,0 +1,2 @@
+gcode-preview
+*.o

README.md

@@ -10,4 +10,34 @@ Building and installing the C version
 1. clone this repository locally on your machine
 2. run `make clean && sudo make install` from within the repository folder
 
+Performance
+-----------
+Quick benchmark of `gcode-preview` vs `gcode-preview-bash` extracting a 800x600 png image from a gcode file:
 
+`gcode-preview-bash`:
+```
+real    0m0.014s
+user    0m0.016s
+sys     0m0.004s
+```
+
+`gcode-preview`:
+```
+real    0m0.002s
+user    0m0.001s
+sys     0m0.000s
+```
+
+Example usage
+-------------
+
+`gcode-preview -i benchy.gcode -o thumb.png`
+
+`gcode-preview-bash benchy.gcode thumb.png`
+
+Ranger / lf integration
+-----------------------
+
+With image previews enabled in [ranger](https://github.com/ranger/ranger/wiki/Image-Previews) or [lf](https://github.com/slavistan/howto-lf-image-previews), it is possible to extend the functionality to get previews for .gcode files, here is an example with lf:
+
+![preview](/assets/lf.png)