是否可以使用TagLibSharp从Lyrics3v2文件中删除Lyrics3v2标记？

Question

我想知道是否可以使用库从MP3文件中删除标记类型。

这文档指出，块条目以单词"LYRICSBEGIN“开头，以"LYRICS200”结尾，同时它还指出，ID3标记应该存在以允许存在Lyrics3v2标记...but --它没有指定是否为ID3v1或E 112ID3v2E 213标记或其中任何一个标签，无论如何，我不理解这一部分，因为E 114Lyrics3v2E 215/code>标记是单个标签类型，不是E 116/code>ID3v 1/ID3v 2<代码>E<217/code>标签的一部分，它在mp3上有自己的条目.我不明白ID3v1/ID3v2“依赖性”意味着什么。

无论如何，假设信息是正确的，那么我应该能够使用TagLibSharp从包含Lyrics3v2标记的mp3文件中删除ID3v1和ID3v2标记，那么该标记也将被删除吗?但是，标记仍然存在。

此外，公开TagLibSharp's类的Lyrics属性似乎不影响Lyrics3v2标记，这一切都非常混乱。

Answer 1

我用taglibsharp编写了这个解决方案

' *************************************************************
' THIS CLASS IS PARTIALLY DEFINED FOR THIS STACKOVERFLOW ANSWER
' *************************************************************

Imports System.IO
Imports System.Text
Imports TagLib

''' <summary>
''' Represents the <c>Lyrics3</c> tag for a MP3 file.
''' </summary>
Public Class Lyrics3Tag

    Protected ReadOnly mp3File As Mpeg.AudioFile

    ''' <summary>
    ''' The maximum length for the <c>Lyrics3</c> block to prevent issues like removing a false-positive block of data.
    ''' <para></para>
    ''' Note that this is a personal attempt to prevent catastrophes, not based on any official info.
    ''' </summary>
    Private ReadOnly maxLength As Integer = 512 ' bytes

    Private Sub New()
    End Sub

    Public Sub New(ByVal mp3File As Mpeg.AudioFile)
        Me.mp3File = mp3File
    End Sub

    ''' <summary>
    ''' Entirely removes the <c>Lyrics3</c> tag.
    ''' </summary>
    <DebuggerStepThrough>
    Public Overridable Sub Remove()

        Dim initVector As New ByteVector(Encoding.UTF8.GetBytes("LYRICSBEGIN"))
        Dim initOffset As Long = Me.mp3File.Find(initVector, startPosition:=0)

        If (initOffset <> -1) Then

            ' The Lyrics3 block can end with one of these two markups, so we need to evaluate both.
            For Each str As String In {"LYRICS200", "LYRICSEND"}

                Dim endVector As New ByteVector(Encoding.UTF8.GetBytes(str))
                Dim endOffset As Long = Me.mp3File.Find(endVector, startPosition:=initOffset)

                If (endOffset <> -1) Then

                    Dim length As Integer = CInt(endOffset - initOffset) + (str.Length)
                    If (length < Me.maxLength) Then
                        Try
                            Me.mp3File.Seek(initOffset, SeekOrigin.Begin)
                            ' Dim raw As String = Me.mp3File.ReadBlock(length).ToString()
                            Me.mp3File.RemoveBlock(initOffset, length)
                            Exit Sub

                        Catch ex As Exception
                            Throw

                        Finally
                            Me.mp3File.Seek(0, SeekOrigin.Begin)

                        End Try

                    Else ' Length exceeds the max length.
                         ' We can handle it or continue...
                        Continue For

                    End If

                End If

            Next str

        End If

    End Sub

End Class

示例用法：

Dim mp3File As New Taglib.Mpeg.AudioFile("filepath")

Using lyrics As New Lyrics3Tag(mp3File)
    lyrics.Remove()
End Using