diff --git a/README.md b/README.md
index be11e3b..ba7bda7 100644
--- a/README.md
+++ b/README.md
@@ -1,145 +1,92 @@
 # go-mp4tag
-MP4 tagging library & CLI tagger written in Go.    
-[Windows, Linux, macOS and Android binaries](https://github.com/Sorrow446/go-mp4tag/releases)
+MP4 tag library written in Go.
 
-
-## Library
 ### Setup
 ```
 go get github.com/Sorrow446/go-mp4tag
 ```
-```go
-import "github.com/Sorrow446/go-mp4tag"
-```
 
 ### Usage Examples
 ```go
-	tags := &mp4tag.Tags{
-		Album: "album",
-		AlbumArtist: "album artist",
-		Title:       "title",
-		TrackNumber: 1,
-		TrackTotal:  20,
-		Genre: "genre",
-		DiskNumber:  3,
-		DiskTotal:   10,
-		Comment:     "comment",
-	}
-	err := mp4tag.Write("1.m4a", tags)
-	if err != nil {
-		panic(err)
-	}
+import "github.com/Sorrow446/go-mp4tag"
 ```
- Write album, album artist, title, track number, track total, genre, disk number, disk total, and comment tags.
- 
- 
- ```go
-	tags := &mp4tag.Tags{
-		Custom: map[string]string{
-			"CUSTOMFIELD": "custom field",
-			"CUSTOMFIELD2": "custom field 2",
-		},
-		Delete: []string{"cover", "genre"},
-	}
-	err := mp4tag.Write("1.m4a", tags)
-	if err != nil {
-		panic(err)
-	}
-```
-Write two custom fields named `CUSTOMFIELD` and `CUSTOMFIELD2`, delete genre tag, and remove cover.
-
-
+Opening is omitted from the examples.
 ```go
-	coverBytes, err := ioutil.ReadFile("cover.jpg")
-	if err != nil {
-		panic(err)
-	}
-	tags := &mp4tag.Tags{
-		Cover: coverBytes,
-	}
-	err = mp4tag.Write("1.m4a", tags)
-	if err != nil {
-		panic(err)
-	}
+mp4, err := mp4tag.Open("1.m4a")
+if err != nil {
+	panic(err)
+}
+defer mp4.Close()
 ```
-Write cover from `cover.jpg`.
 
+Read album title:
 ```go
-type Tags struct {
-	Album       string
-	AlbumArtist string
-	Artist      string
-	Comment     string
-	Composer    string
-	Copyright   string
-	Cover       []byte
-	Custom      map[string]string
-	Delete      []string
-	DiskNumber  int
-	DiskTotal   int
-	Genre       string
-	Label       string
-	Title       string
-	TrackNumber int
-	TrackTotal  int
-	Year        string
+tags, err := mp4.Read()
+if err != nil {
+	panic(err)
+}
+fmt.Println(tags.Album)
+```
+
+Extract all covers:
+```go
+tags, err := mp4.Read()
+if err != nil {
+	panic(err)
+}
+
+for idx, pic := range tags.Pictures {
+	fname := fmt.Sprintf("out_%03d.jpg", idx+1)
+	err = os.WriteFile(fname, pic.Data, 0666)
+	if err != nil {
+		panic(err)
+	}
 }
 ```
-iTunes-style metadata only.       
-Delete strings: album, albumartist, artist, comment, composer, copyright, cover, disk, genre, label, title, track, year.    
-Custom tag deletion is not implemented yet.
 
-## CLI
-go-mp4tag also has a CLI version if you'd like to call it outside of Go.
+Write two covers:
+```go
+	picOneData, err := os.ReadFile("1.jpg")
+	if err != nil {
+		panic(err)
+	}
+
+	picTwoData, err := os.ReadFile("2.jpg")
+	if err != nil {
+		panic(err)
+	}
+
+	picOne := &mp4tag.MP4Picture{Data: picOneData}
+	picTwo := &mp4tag.MP4Picture{Data: picTwoData}
+
+	tags := &mp4tag.MP4Tags{
+		Pictures: []*mp4tag.MP4Picture{picOne, picTwo},
+	}
+
+	err = mp4.Write(tags, []string{})
+	if err != nil {
+		panic(err)
+	}
 ```
-Usage: mp4tag_x64.exe [--album ALBUM] [--albumArtist ALBUMARTIST] [--artist ARTIST] [--comment COMMENT] [--composer COMPOSER] [--copyright COPYRIGHT] [--cover COVER] [--custom CUSTOM] [--delete DELETE] [--diskNumber DISKNUMBER] [--diskTotal DISKTOTAL] [--genre GENRE] [--label LABEL] [--title TITLE] [--trackNumber TRACKNUMBER] [--trackTotal TRACKTOTAL] [--year YEAR] FILEPATH
 
-Positional arguments:
-  FILEPATH               Path of file to write to.
 
-Options:
-  --album ALBUM          Write album tag.
-  --albumArtist ALBUMARTIST
-                         Write album artist tag.
-  --artist ARTIST        Write artist tag.
-  --comment COMMENT      Write comment tag.
-  --composer COMPOSER    Write composer tag.
-  --copyright COPYRIGHT
-                         Write copyright tag.
-  --cover COVER          Path of cover to write. JPEG is recommended.
-  --custom CUSTOM        Write custom tags. Multiple tags with the same field name can be written.
-                         Example: "--custom MYCUSTOMFIELD1=value1 MYCUSTOMFIELD2=value2"
-  --delete DELETE, -d DELETE
-                         Tags to delete.
-                         Options: album, albumartist, artist, comment, composer, copyright, cover, disk, genre, label, title, track, year.
-                         Example: "-d album albumartist"
-  --diskNumber DISKNUMBER
-                         Write disk number tag.
-  --diskTotal DISKTOTAL
-                         Write disk total tag. Can't be written without disk number tag.
-  --genre GENRE          Write genre tag.
-  --label LABEL          Write label tag.
-  --title TITLE          Write title tag.
-  --trackNumber TRACKNUMBER
-                         Write track number tag.
-  --trackTotal TRACKTOTAL
-                         Write track total tag. Can't be written without track number tag.
-  --year YEAR            Write year tag.
-  --help, -h             display this help and exit
-  ```
-  You must use double quotes for values with spaces in.
-  
-  `mp4tag_x64.exe 1.m4a --artist artist --albumArtist "album artist"`    
-  Write artist and album artist tags.
-  
-  `mp4tag_x64.exe 1.m4a --cover cover.jpg`    
-  Write cover from `cover.jpg`
-  
-  `mp4tag_x64.exe 1.m4a --custom "MY CUSTOM FIELD WITH SPACES"=value1 MYCUSTOMFIELD1="value with spaces" -d cover genre"`    
-  Write two custom fields named `MY CUSTOM FIELD WITH SPACES`, and `MYCUSTOMFIELD1`, delete genre tag, and remove cover.
+Write track number and total:
+```go
+tags := &mp4tag.MP4Tags{
+	TrackNumber: 1,
+	TrackTotal: 10,
+}
 
-## Thank you
- go-mp4tag relies heavily on abema's go-mp4 library.
+err = mp4.Write(tags, []string{})
+if err != nil {
+	panic(err)
+}
+```
 
-## Disclaimer
-Although go-mp4tag has been thoroughly tested, I will not be responsible for the very tiny chance of any corruption to your MP4 files.
+Delete comment:
+```go
+err = mp4.Write(&mp4tag.MP4Tags{}, []string{"comment"})
+if err != nil {
+	panic(err)
+}
+```