README: add output of --help

README.md

@@ -28,3 +28,45 @@ Tested and run regularly on Fedora, but should work on other distributions with
 * unpaper (for software deskew)
 * flock (usually provided by util-linux) (for properly ordered verbose logs)
 * tesseract (to make searchable PDFs)
+
+## Getting Started
+
+```
+# scan --help
+scan [OPTIONS]... [OUTPUT]
+
+OPTIONS
+ -v, --verbose
+   Verbose output (this will slow down the scan due to the need to prevent interleaved output)
+ -d, --duplex
+   Duplex scanning
+ -m, --mode
+   Mode e.g. Lineart (default), Halftone, Gray, Color, etc.
+ -r, --resolution
+   Resolution e.g 300 (default)
+ -a, --append
+   Append output to existing scan
+ -e, --max <pages>
+   Max number of pages e.g. 2 (default is all pages)
+ -t, --truncate <pages>
+   Truncate number of pages from end e.g. 1 (default is none)
+ -s, --size
+   Page Size as type e.g. Letter (default), Legal, A4, no effect if --crop is specified
+ -ph, --page-height
+   Custom Page Height in mm
+ -pw, --page-width
+   Custom Page Width in mm
+ --crop
+   Crop to contents (driver must support this)
+ --deskew
+   Run driver deskew (driver must support this)
+ --unpaper
+   Run post-processing deskew and black edge detection (requires unpaper)
+ --ocr
+   Run OCR to make the PDF searchable (requires tesseract)
+
+OUTPUT
+ -o, --output <outputfile>
+   Output to named file default=scan.pdf
+ -l, --outputlist <outputfile-1...outputfile-n> Output to named files for each scanned page, can be used with append
+```