Update readme description of new feature

Author: philipbl

README.md

@@ -1,10 +1,10 @@
 # Duplicate Image Finder
 
-This Python script finds duplicate images using a perspective hash (pHash) to compare images. pHash ignores the image size and file size and instead creates a hash based on the pixels of the image. This allows you to find duplicate pictures that have been rotated, have changed metadata, and edited.
+This Python script finds duplicate images using a [perspective hash (pHash)](http://www.phash.org) to compare images. pHash ignores the image size and file size and instead creates a hash based on the pixels of the image. This allows you to find duplicate pictures that have been rotated, have changed metadata, and edited.
 
-This script hashes images added to it, storing the hash into a database. To find duplicate images, hashes are compared. If the hash is the same between two images, then they are marked as duplicates. A web interface is provided to delete duplicate images easily.
+This script hashes images added to it, storing the hash into a database. To find duplicate images, hashes are compared. If the hash is the same between two images, then they are marked as duplicates. A web interface is provided to delete duplicate images easily. If you are feeling lucky, there is an option to automatically delete duplicate files.
 
-As a word of caution, pHash is not perfect. I have found that duplicate pictures sometimes have different hashes and similar pictures have the same hash. This script is a great starting point for cleaning your photo library of duplicate pictures, but make sure you look at the pictures before you delete them.
+As a word of caution, pHash is not perfect. I have found that duplicate pictures sometimes have different hashes and similar (but not the same) pictures have the same hash. This script is a great starting point for cleaning your photo library of duplicate pictures, but make sure you look at the pictures before you delete them. You have been warned! I hold no responsibility for any family memories that might be lost because of this script.
 
 This script has only been tested with Python 3 and is still pretty rough around the edges. Use at your own risk.
 
@@ -17,7 +17,6 @@ First, install this script. This can be done by either cloning the repository or
 git clone https://github.com/philipbl/duplicate-images.git
 ```
 
-
 Next, download all required modules. This script has only been tested with Python 3. I would suggest that you make a virtual environment, setting Python 3 as the default python executable (`mkvirtualenv --python=/usr/local/bin/python3 <name>`)
 ```
 pip install -r requirements.txt
@@ -29,34 +28,42 @@ python duplicate_finder.py
 ```
 
 
-
 ## Usage
 
 ```
 Usage:
-    duplicate_finder.py add <path> ...
-    duplicate_finder.py remove <path> ...
-    duplicate_finder.py clear
-    duplicate_finder.py show
-    duplicate_finder.py find [--print] [--match-time] [--trash=<trash_path>]
+    duplicate_finder.py add <path> ... [--db=<db_path>] [--parallel=<num_processes>]
+    duplicate_finder.py remove <path> ... [--db=<db_path>]
+    duplicate_finder.py clear [--db=<db_path>]
+    duplicate_finder.py show [--db=<db_path>]
+    duplicate_finder.py find [--print] [--match-time] [--trash=<trash_path>] [--db=<db_path>]
+    duplicate_finder.py dedup [--confirm] [--match-time] [--trash=<trash_path>]
     duplicate_finder.py -h | –-help
 
 Options:
-    -h, -–help            Show this screen
+    -h, -–help                Show this screen
+
+    --db=<db_path>            The location of the database. (default: ./db)
+
+    --parallel=<num_processes> The number of parallel processes to run to hash the image
+                               files (default: 8).
 
     find:
         --print               Only print duplicate files rather than displaying HTML file
         --match-time          Adds the extra constraint that duplicate images must have the
                               same capture times in order to be considered.
         --trash=<trash_path>  Where files will be put when they are deleted (default: ./Trash)
+
+     dedup:
+        --confirm             Confirm you realize this will delete duplicates automatically.
 ```
 
 ### Add
 ```
 python duplicate_finder.py add /path/to/images
 ```
 
-When a path is added, image files are recursively searched for. In particular, `JPEG`, `PNG`, `GIF`, and `TIFF` images are searched for. Any image files found will be hashed. Adding a path uses 8 processes to hash images in parallel so the CPU usage is very high.
+When a path is added, image files are recursively searched for. In particular, `JPEG`, `PNG`, `GIF`, and `TIFF` images are searched for. Any image files found will be hashed. Adding a path uses 8 processes (by default) to hash images in parallel so the CPU usage is very high.
 
 ### Remove
 ```
@@ -84,9 +91,14 @@ Prints the contents database.
 python duplicate_finder.py find [--print] [--match-time] [--trash=<trash_path>]
 ```
 
-Finds duplicate pictures that have been hashed. This will find images that have the same hash stored in the database. There are a few options associated with find. By default, when this command is run, a webpage is displayed showing duplicate pictures and a server is started that allows for the pictures to be deleted (images are not actually deleted, but moved to a trash folder). The first option, `--print`, prints all duplicate pictures and does not display a webpage or start the server. `--match-time` adds the extra constraint that images must have the same EXIF time stamp to be considered duplicate pictures. Last, `--trash=<trash_path>` lets you select a path to where you want files to be put when they are deleted. The trash path must already exist before a image is deleted.
+Finds duplicate pictures that have been hashed. This will find images that have the same hash stored in the database. There are a few options associated with `find`. By default, when this command is run, a webpage is displayed showing duplicate pictures and a server is started that allows for the pictures to be deleted (images are not actually deleted, but moved to a trash folder -- I really don't want you to make a mistake). The first option, `--print`, prints all duplicate pictures and does not display a webpage or start the server. `--match-time` adds the extra constraint that images must have the same EXIF time stamp to be considered duplicate pictures. Last, `--trash=<trash_path>` lets you select a path to where you want files to be put when they are deleted. The trash path must already exist before a image is deleted.
 
+### Dedup
+```
+python duplicate_finder.py dedup [--confirm] [--match-time] [--trash=<trash_path>]
+```
 
+Similar to find, except that it deletes any duplicate picture it finds rather than bringing up a webpage. To make sure you really want to do this, you must provide the `--confirm` flag. See `find` for a description of the other options.
 
 ## Requirements