Question

我有许多MPEG-4文件，这些文件是从各种数码相机格式转码而来的，文件系统修改日期是正确的。我想设置“Media Created”标签以匹配。这可以在Windows资源管理器中通过“属性”窗口的“详细信息”选项卡手动完成。设置“已创建媒体”非常有用，因为Windows Live照片库会在此字段中键入其“采取日期”属性。不幸的是，文件数量使得手工设置所有日期变得不切实际。

有几种自动化途径有潜力。 TagLib#似乎支持所有MP4标记，但获取更多基本标记的API尚不清楚。另一个角度是Windows shell。据推测，Windows资源管理器正在使用它来编写标签。通过shell有example for reading，但似乎没有用于编写的API。

Answer 1

我在exiftool取得了成功。以下是列出媒体文件中所有标签并更新所选标签的命令（也可以批量处理文件）：

int sum = behzad.Compare_closed_numbers_in_CRM_and_Billing_system_detail_counters
         .Where(t=>t.fileid == point.id)
         .Select(t => Convert.ToInt32(t.Count)).Sum();

Answer 2

使用Windows Property System。请参阅Property Edit Sample开始使用。设置这些属性：

System.DateImported
System.Media.DateEncoded
System.ItemDate

Answer 3

我通过直接写入读/写MP4文件格式来解决这个问题。这是VB中的代码：

Sub Main()
    ' Retrieve creation-time and modification-time, embedded inside the metadata of MP4 files
    Dim ft = Mp4Times("a.mp4")
    Console.WriteLine(ft.CreationTime)
    Console.WriteLine(ft.ModificationTime)

    ' Update those times
    Mp4Times("a.mp4", Date.Now, Date.Now)
End Sub

Class FileTimes
    Public CreationTime As Date
    Public ModificationTime As Date
End Class

Function Mp4Times(fn As String, Optional newCreationTime As Date? = Nothing, Optional newModificationTime As Date? = Nothing) As FileTimes
    Dim ft As FileTimes
    Using f = If(newCreationTime.HasValue OrElse newModificationTime.HasValue, IO.File.Open(fn, IO.FileMode.Open), IO.File.OpenRead(fn))
        f.Seek(0, IO.SeekOrigin.End) : Dim fend = f.Position

        ' The file is made up of a sequence of boxes, with a standard way to find size and FourCC "kind" of each.
        ' Some box kinds contain a kind-specific blob of binary data. Other box kinds contain a sequence
        ' of sub-boxes. You need to look up the specs for each kind to know whether it has a blob or sub-boxes.
        ' We look for a top-level box of kind "moov", which contains sub-boxes, and then we look for its sub-box
        ' of kind "mvhd", which contains a binary blob. This is where Creation/ModificationTime are stored.
        Dim pos = 0L, payloadStart = 0L, payloadEnd = 0L, boxKind = ""
        While ReadNextBoxInfo(f, pos, fend, boxKind, payloadStart, payloadEnd) AndAlso boxKind <> "moov"
            pos = payloadEnd
        End While
        If boxKind <> "moov" Then Return Nothing
        pos = payloadStart : fend = payloadEnd
        While ReadNextBoxInfo(f, pos, fend, boxKind, payloadStart, payloadEnd) AndAlso boxKind <> "mvhd"
            pos = payloadEnd
        End While
        If boxKind <> "mvhd" Then Return Nothing

        ' The "mvhd" binary blob consists of 1byte (version, either 0 or 1), 3bytes (flags),
        ' and then either 4bytes (creation), 4bytes (modification)
        ' or 8bytes (creation), 8bytes (modification)
        ' If version=0 then it's the former, otherwise it's the later.
        ' In both cases "creation" and "modification" are big-endian number of seconds since 1st Jan 1904 UTC
        f.Seek(pos + 8, IO.SeekOrigin.Begin) : Dim version = f.ReadByte()
        f.Seek(pos + 12, IO.SeekOrigin.Begin)
        Dim creationTime As Date, modificationTime As Date
        '
        If newCreationTime.HasValue Then
            creationTime = newCreationTime.Value
            If version = 0 Then Write4byteDate(f, creationTime) Else Write8byteDate(f, creationTime)
        Else
            creationTime = If(version = 0, ReadNext4byteDate(f), ReadNext8byteDate(f))
        End If
        '
        If newModificationTime.HasValue Then
            modificationTime = newModificationTime.Value
            If version = 0 Then Write4byteDate(f, modificationTime) Else Write8byteDate(f, modificationTime)
        Else
            modificationTime = If(version = 0, ReadNext4byteDate(f), ReadNext8byteDate(f))
        End If
        ft = New FileTimes With {.CreationTime = creationTime, .ModificationTime = modificationTime}
    End Using

    If newCreationTime.HasValue Then IO.File.SetCreationTime(fn, newCreationTime.Value)
    If newModificationTime.HasValue Then IO.File.SetLastWriteTime(fn, newModificationTime.Value)
    Return ft
End Function

Function ReadNextBoxInfo(f As IO.Stream, pos As Long, fend As Long, ByRef boxKind As String, ByRef payloadStart As Long, ByRef payloadEnd As Long) As Boolean
    boxKind = "" : payloadStart = 0 : payloadEnd = 0
    If pos + 8 > fend Then Return False
    Dim b(3) As Byte
    f.Seek(pos, IO.SeekOrigin.Begin)
    f.Read(b, 0, 4) : If BitConverter.IsLittleEndian Then Array.Reverse(b)
    Dim size = BitConverter.ToUInt32(b, 0)
    f.Read(b, 0, 4)
    Dim kind = ChrW(b(0)) & ChrW(b(1)) & ChrW(b(2)) & ChrW(b(3))
    If size <> 1 Then
        If pos + size > fend Then Return False
        boxKind = kind : payloadStart = pos + 8 : payloadEnd = payloadStart + size - 8 : Return True
    End If
    If size = 1 AndAlso pos + 16 <= fend Then
        ReDim b(7)
        f.Read(b, 0, 8) : If BitConverter.IsLittleEndian Then Array.Reverse(b)
        Dim size2 = CLng(BitConverter.ToUInt64(b, 0))
        If pos + size2 > fend Then Return False
        boxKind = kind : payloadStart = pos + 16 : payloadEnd = payloadStart + size2 - 16 : Return True
    End If
    Return False
End Function

ReadOnly TZERO As Date = New Date(1904, 1, 1, 0, 0, 0, DateTimeKind.Utc)

Function ReadNext4byteDate(f As IO.Stream) As Date
    Dim b(3) As Byte
    f.Read(b, 0, 4) : If BitConverter.IsLittleEndian Then Array.Reverse(b)
    Dim secs = BitConverter.ToUInt32(b, 0)
    Return TZERO.AddSeconds(secs)
End Function

Function ReadNext8byteDate(f As IO.Stream) As Date
    Dim b(7) As Byte
    f.Read(b, 0, 8) : If BitConverter.IsLittleEndian Then Array.Reverse(b)
    Dim secs = BitConverter.ToUInt64(b, 0)
    Return TZERO.AddSeconds(secs)
End Function

Sub Write4byteDate(f As IO.Stream, d As Date)
    Dim secs = CUInt((d - TZERO).TotalSeconds)
    Dim b = BitConverter.GetBytes(secs) : If BitConverter.IsLittleEndian Then Array.Reverse(b)
    f.Write(b, 0, 4)
End Sub

Sub Write8byteDate(f As IO.Stream, d As Date)
    Dim secs = CULng((d - TZERO).TotalSeconds)
    Dim b = BitConverter.GetBytes(secs) : If BitConverter.IsLittleEndian Then Array.Reverse(b)
    f.Write(b, 0, 8)
End Sub

Answer 4

这是我编写的PowerShell脚本，用于使用exiftool批量解决此问题。

它将把所有exiftool命令写到CMD文件中。 exiftool.exe必须与文件和exiftool.exe位于同一位置

请确保将Powershell ISE / PS1文件放在您正在处理文件的同一目录中。完成后，您可以在记事本中查看CMD文件。如果一切正常，请使用CMD运行它。：）

$allFiles = Get-ChildItem -Filter * -Exclude *.exe

$exifFile = @()
$exifFile += "@echo off"

foreach($file in $allFiles)
{
    $month = $file.CreationTime.Month
    $day = $file.CreationTime.Day
    $hour = $file.CreationTime.Hour
    $min = $file.CreationTime.Minute
    $sec = $file.CreationTime.Second

    if($month -lt 10)
    {
        $month = "0$($file.CreationTime.Month)"
    }

    if($day -lt 10)
    {
        $day = "0$($file.CreationTime.Day)"
    }

    if($hour -lt 10)
    {
        $hour = "0$($file.CreationTime.Hour)"
    }

    if($min -lt 10)
    {
        $min = "0$($file.CreationTime.Minute)"
    }

    if($sec -lt 10)
    {
        $sec = "0$($file.CreationTime.Second)"
    }

    $exifFile += "exiftool.exe ^ -QuickTime:CreateDate=`"$($file.CreationTime.Year):$($month):$($day) $($hour):$($min):$($sec)`" ^ `"$($file.Name)`""
}

$exifFile | Out-File "MassCreateFix.cmd" -Encoding ascii -NoClobber

如何在MPEG-4文件上设置“媒体创建”日期

4 个答案: