doc: add Usage to README.md

Author: coolaj86

README.md

@@ -5,7 +5,7 @@
 AtomicParsley is a lightweight command line program for reading, parsing and
 setting metadata into MPEG-4 files, in particular, iTunes-style metadata.
 
-## Installation
+## Install
 
 ### macOS
 
@@ -36,7 +36,93 @@ Note that the version available in brew may lag behind the latest version of the
 * Download the `AtomicParsleyAlpine.zip` file and extract `AtomicParsley`
 * And finally `apk add libstdc++`
 
-### Building from Source
+## Usage
+
+```txt
+AtomicParsley sets metadata into MPEG-4 files & derivatives supporting 3 tag
+ schemes: iTunes-style, 3GPP assets & ISO defined copyright notifications.
+
+AtomicParsley quick help for setting iTunes-style metadata into MPEG-4 files.
+
+General usage examples:
+  AtomicParsley /path/to.mp4 -T 1
+  AtomicParsley /path/to.mp4 -t +
+  AtomicParsley /path/to.mp4 --artist "Me" --artwork /path/to/art.jpg
+  Atomicparsley /path/to.mp4 --albumArtist "You" --podcastFlag true
+  Atomicparsley /path/to.mp4 --stik "TV Show" --advisory explicit
+
+Getting information about the file & tags:
+  -T  --test        Test file for mpeg4-ishness & print atom tree
+  -t  --textdata    Prints tags embedded within the file
+  -E  --extractPix  Extracts pix to the same folder as the mpeg-4 file
+
+Setting iTunes-style metadata tags
+  --artist       (string)     Set the artist tag
+  --title        (string)     Set the title tag
+  --album        (string)     Set the album tag
+  --genre        (string)     Genre tag (see --longhelp for more info)
+  --tracknum     (num)[/tot]  Track number (or track number/total tracks)
+  --disk         (num)[/tot]  Disk number (or disk number/total disks)
+  --comment      (string)     Set the comment tag
+  --year         (num|UTC)    Year tag (see --longhelp for "Release Date")
+  --lyrics       (string)     Set lyrics (not subject to 256 byte limit)
+  --lyricsFile   (/path)      Set lyrics to the content of a file
+  --composer     (string)     Set the composer tag
+  --copyright    (string)     Set the copyright tag
+  --grouping     (string)     Set the grouping tag
+  --artwork      (/path)      Set a piece of artwork (jpeg or png only)
+  --bpm          (number)     Set the tempo/bpm
+  --albumArtist  (string)     Set the album artist tag
+  --compilation  (boolean)    Set the compilation flag (true or false)
+  --hdvideo      (number)     Set the hdvideo flag to one of:
+                              false or 0 for standard definition
+                              true or 1 for 720p
+                              2 for 1080p
+  --advisory     (string*)    Content advisory (*values: 'clean', 'explicit')
+  --stik         (string*)    Sets the iTunes "stik" atom (see --longhelp)
+  --description  (string)     Set the description tag
+  --longdesc     (string)     Set the long description tag
+  --storedesc    (string)     Set the store description tag
+  --TVNetwork    (string)     Set the TV Network name
+  --TVShowName   (string)     Set the TV Show name
+  --TVEpisode    (string)     Set the TV episode/production code
+  --TVSeasonNum  (number)     Set the TV Season number
+  --TVEpisodeNum (number)     Set the TV Episode number
+  --podcastFlag  (boolean)    Set the podcast flag (true or false)
+  --category     (string)     Sets the podcast category
+  --keyword      (string)     Sets the podcast keyword
+  --podcastURL   (URL)        Set the podcast feed URL
+  --podcastGUID  (URL)        Set the episode's URL tag
+  --purchaseDate (UTC)        Set time of purchase
+  --encodingTool (string)     Set the name of the encoder
+  --encodedBy    (string)     Set the name of the Person/company who encoded the file
+  --apID         (string)     Set the Account Name
+  --cnID         (number)     Set the iTunes Catalog ID (see --longhelp)
+  --geID         (number)     Set the iTunes Genre ID (see --longhelp)
+  --xID          (string)     Set the vendor-supplied iTunes xID (see --longhelp)
+  --gapless      (boolean)    Set the gapless playback flag
+  --contentRating (string*)   Set tv/mpaa rating (see -rDNS-help)
+
+Deleting tags
+  Set the value to "":        --artist "" --stik "" --bpm ""
+  To delete (all) artwork:    --artwork REMOVE_ALL
+  manually removal:           --manualAtomRemove "moov.udta.meta.ilst.ATOM"
+
+More detailed iTunes help is available with AtomicParsley --longhelp
+Setting reverse DNS forms for iTunes files: see --reverseDNS-help
+Setting 3gp assets into 3GPP & derivative files: see --3gp-help
+Setting copyright notices for all files: see --ISO-help
+For file-level options & padding info: see --file-help
+Setting custom private tag extensions: see --uuid-help
+Setting ID3 tags onto mpeg-4 files: see --ID3-help
+
+----------------------------------------------------------------------
+AtomicParsley version: 20221229.172126.0 d813aa6e0304ed3ab6d92f1ae96cd52b586181ec (utf8)
+
+Submit bug fixes to https://github.com/wez/atomicparsley
+```
+
+## Build from Source
 
 If you are building from source you will need `cmake` and `make`.
 On Windows systems you'll need Visual Studio or MingW.
@@ -53,7 +139,6 @@ will generate an `AtomicParsley` executable.
 zlib  - used to compress ID3 frames & expand already compressed frames
         available from http://www.zlib.net
 
-
 ## A note on maintenance!
 
 > I made some fixes to the original project on sourceforge back in 2009 and