armbrustconsulting.com

Resources | VB | Update WMAs

Update WMA Files:

In the past year Microsoft has released an update to their Windows Media Encoder SDK. This has made encoding audio files (such as .WAVs and .MP3s) a much easier process in Visual Basic. However, the documentation for this SDK is not always very helpful for some fairly basic Encoding issues.

For example, something that I have found a great need for has been the ability to update the properties (CopyRight, Description, Title and Author) of WMA files without having to entirely reencode them. There is a fairly easy way to do this. This tutorial will show you how to update a batch of WMA files using an xml file and a visual basic application.

The first thing you need to do is to create an XML template that will hold the values of the properties you will be updating in your WMA file(s). You can create the file in any text editor, and save it in the folder that you have your VB application. Name the file XMLConfigFile.xml. Put this in your xml file:

<?xml version="1.0"?> <WMBasicEdit > <Attributes > <WMENC_STRING Name="Copyright" Value="**copyright**" /> <WMENC_STRING Name="Author" Value="**copyright**" /> <WMENC_STRING Name="Title" Value="**copyright**" /> <WMENC_STRING Name="Description" Value="**copyright**" /> </Attributes> </WMBasicEdit>

Now create a new VBApplication, with 1 Command Button (named CmdConfig) and 1 Label (Label1). Also, in your VB Project add a reference to Windows Media Encoder and Windows Scripting Runtime. Add the following code to your VB Form:

'Declare Global Variables Private Const cXMLConfig = "XMLConfigFile.xml" Public gXMLString As String Private Const cXMLConfigTemp = "XmlTemp.xml" Dim WithEvents BasicEdit As WMEncBasicEdit Dim bDone As Boolean Private Sub UpdateConfigForWMA(fileName As String, Description As String, _ CopyRight As String, author As String, _ title As String) Dim fileNameHold As String Dim NewXmlConfig As String NewXmlConfig = Replace(gXMLString, "**title**", title) NewXmlConfig = Replace(NewXmlConfig, "**author**", author) NewXmlConfig = Replace(NewXmlConfig, "**copyright**", CopyRight) NewXmlConfig = Replace(NewXmlConfig, "**description", Description) Dim ts As TextStream Dim fso As FileSystemObject Set fso = New FileSystemObject Set ts = fso.CreateTextFile(App.Path & "\" & cXMLConfigTemp, True) ts.Write NewXmlConfig ts.Close Set ts = Nothing Set fso = Nothing DoEvents ' Create the WMEncBasicEdit object. Set BasicEdit = New WMEncBasicEdit ' Specify the input and output files. BasicEdit.MediaFile = fileName BasicEdit.OutputFile = fileName ' Specify a configuration file. BasicEdit.ConfigFile = App.Path & "\" & cXMLConfigTemp ' Add indexing to the file. ' BasicEdit.Index = True ' Trim 15 seconds from the beginning and the end of the file. 'BasicEdit.MarkIn = 1 'BasicEdit.MarkOut = BasicEdit.Duration - 15000 BasicEdit.start End Sub Private Sub cmdConfig_Click() Dim fileCtr As Double Dim fso As FileSystemObject Dim fold As Folder Dim fil As File Set fso = New FileSystemObject bDone = False Set fold = fso.GetFolder(INSERTFOLDERNAMETHATHASAUDIOFILES) fileCtr = 0 For Each fil In fold3.Files Author = "Author" Title = "Title" CopyRight = "CopyRight" Description = "Description" UpdateConfigForWMA CStr(fil.Path), CStr(Description), CStr(CopyRight), _ CStr(Author), CStr(Title) DoEvents Do Until bDone = True DoEvents Loop bDone = False fileCtr = fileCtr + 1 Label1.Caption = "Moved: " & fileCtr DoEvents Next MsgBox "DONE" Set fold = Nothing Set fil = Nothing Set fso = Nothing End Sub Function GetConfigWmaInfo(fileName As String) As String 'in my project I set up this function to return a series of values delimited by a | 'the information was pulled from a Database table that held all the audio file names End Function ' This events procedure checks for the end of the editing process. Private Sub BasicEdit_OnStateChange(ByVal EnumState As _ WMEncoderLib.WMENC_BASICEDIT_STATE) If EnumState = WMENC_BASICEDIT_STOPPED Then bDone = True End Sub Private Sub Form_Load() 'on form load, fill up a variable with the text from your XMLConfigFile Dim fso As FileSystemObject Set fso = New FileSystemObject Dim ts As TextStream Set ts = fso.OpenTextFile(App.Path & "\" & cXMLConfig) gXMLString = ts.ReadAll ts.Close Set ts = Nothing Set fso = Nothing End Sub

Then, load up your VB App, click the button and sit back while your WMA files are updated! Related Links: Main Forum

Want to discuss this article, or other development issues? Visit our message boards!

Or contact us directly with a comment or question on this article: click here !

armbrustconsulting.com