How do I predict a file size before the file is created in vb.net?

Question

Could anyone help me please. I have made a Text-To-Speech application using SpeechSynthesizer, it has Play, Pause, Resume, and Stop, but also you can change the voice, rate and volume, and also save as audio (mp3, wav).

But the question is: How do I display the file size of the audio file before the file is created depending on

My code for Form1 is:

Imports System.Speech.Synthesis
Imports System.IO
Public Class Form1
Dim speech As New SpeechSynthesizer
Private Sub ControlBtn_Click(sender As System.Object, e As System.EventArgs) Handles ControlBtn.Click
    Form2.ShowDialog()
End Sub
Private Sub speakCompleted(ByVal sender As Object, ByVal e As SpeakCompletedEventArgs)
    Dim cancelled = e.Cancelled

    PlayBtn.Enabled = True
    PauseBtn.Enabled = False
    ResumeBtn.Enabled = False
    StopBtn.Enabled = False
End Sub
Private Sub PlayBtn_Click(sender As System.Object, e As System.EventArgs) Handles PlayBtn.Click
    speech.SelectVoice(Form2.ComboBox1.Text)
    speech.Rate = Form2.RateTB.Value
    speech.Volume = Form2.VolumeTB.Value
    speech.SpeakAsync(RichTextBox1.Text)
    PlayBtn.Enabled = False
    ResumeBtn.Enabled = False
    PauseBtn.Enabled = True
    StopBtn.Enabled = True
    AddHandler speech.SpeakCompleted, AddressOf speakCompleted
End Sub

Private Sub StopBtn_Click(sender As System.Object, e As System.EventArgs) Handles StopBtn.Click
    speech.SpeakAsyncCancelAll()
    StopBtn.Enabled = False
    PauseBtn.Enabled = False
    ResumeBtn.Enabled = False
    PlayBtn.Enabled = True
End Sub

Private Sub ResumeBtn_Click(sender As System.Object, e As System.EventArgs) Handles ResumeBtn.Click
    speech.Resume()
    PlayBtn.Enabled = False
    ResumeBtn.Enabled = False
    PauseBtn.Enabled = True
    StopBtn.Enabled = True
End Sub

Private Sub PauseBtn_Click(sender As System.Object, e As System.EventArgs) Handles PauseBtn.Click
    speech.Pause()
    PauseBtn.Enabled = False
    PlayBtn.Enabled = False
    StopBtn.Enabled = True
    ResumeBtn.Enabled = True
End Sub

Private Sub SaveAsAudioBtn_Click(sender As System.Object, e As System.EventArgs) Handles SaveAsAudioBtn.Click
    Dim mes As New MsgBoxResult
    mes = MsgBox("Voice: " & Form2.ComboBox1.Text & vbNewLine & "Rate: " & Form2.RateTB.Value & vbNewLine & "Volume: " & Form2.VolumeTB.Value & vbNewLine & vbNewLine & "Your file size has been estimated at." & vbNewLine & vbNewLine & "Do you want to proceed?", MsgBoxStyle.YesNo, "Save as Audio")
    If mes = MsgBoxResult.Yes Then
        SaveFileDialog1.Filter = "MPEG-2 Audio Layer III (*.mp3)|*.mp3|WAVeform audio format (*.wav)|*.wav"
        SaveFileDialog1.Title = "Save as Audio file"
        SaveFileDialog1.RestoreDirectory = True
        If SaveFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
            Dim fs As New FileStream(SaveFileDialog1.FileName, FileMode.Create, FileAccess.Write)
            speech.SelectVoice(Form2.ComboBox1.Text)
            speech.Rate = Form2.RateTB.Value
            speech.Volume = Form2.VolumeTB.Value
            speech.SetOutputToWaveStream(fs)
            speech.Speak(RichTextBox1.Text)
            fs.Close()
        End If
    ElseIf mes = MsgBoxResult.No Then

    End If
End Sub
End Class

And the code for Form2 is:

Imports System.Speech.Synthesis
Imports System.Collections.ObjectModel

Public Class Form2
Dim speech As New SpeechSynthesizer
Private Sub Form2_Load(sender As System.Object, e As System.EventArgs)  Handles MyBase.Load
    Dim objvoices As ReadOnlyCollection(Of InstalledVoice) = Speech.GetInstalledVoices(Globalization.CultureInfo.CurrentCulture)
    Dim objvoiceInformation As VoiceInfo = objvoices(0).VoiceInfo
    For Each tmpvoice As InstalledVoice In objvoices
        objvoiceInformation = tmpvoice.VoiceInfo
        ComboBox1.Items.Add(objvoiceInformation.Name.ToString)
    Next
End Sub
End Class

It would be great if you could give me the code for it.

score 0 · Answer 1 · answered Apr 19 '15 at 19:32

Some math plus some experiments should help

expected size = sample rate * average bytes per sample * recording time

You will have to make experiments in order figure out the average bytes per sample produced by different formats and possibly different voices. The pitch of the voice influences amount of data produced. I am not sure if and how the volume influences the file size. Again make experiments!

I assume that the file size grows proportionally with the sample rate; however this depends on the compression algorithms used (and those depend on the codecs).

There is no exact answer to your question. Finding the right parameters and formula involves some black magic.

Thanks. I'll give it go with your solution. – MJAS Apr 22 '15 at 22:58 — MJAS, Apr 22 '15 at 22:58

How do I predict a file size before the file is created in vb.net?

1 Answers1