Differenze tra le versioni di "Analizzare il valore RMS, il picco e il decay dei dati audio mediante gb.media"
Da Gambas-it.org - Wikipedia.
| Riga 187: | Riga 187: | ||
| − | + | Public Sub _new() | |
With Me | With Me | ||
| Riga 203: | Riga 203: | ||
End With | End With | ||
| − | + | End | |
| − | + | Public Sub Tasto_Click() | |
| − | + | ||
| − | + | If tb.Value Then | |
| − | + | Dim src, par, con, lev, snk As MediaControl | |
| − | + | ||
| − | + | pl = New MediaPipeline As "Pipeline" | |
| − | + | src = New MediaControl(pl, "filesrc") | |
| − | + | src["location"] = "<FONT Color=gray>''/percorso/del/file.ogg''</font>" | |
| − | + | par = New MediaControl(pl, "oggdemux") | |
| − | + | con = New MediaControl(pl, "vorbisdec") | |
| − | + | lev = New MediaControl(pl, "level") | |
| − | + | snk = New MediaControl(pl, "alsasink") | |
| − | + | src.LinkTo(par) | |
| − | + | par.LinkLaterTo(con) | |
| − | + | con.LinkTo(lev) | |
| − | + | lev.LinkTo(snk) | |
| − | + | ||
| − | + | pl.Play() | |
| − | + | Wait pl.Duration | |
| − | + | pl.Close | |
| − | + | ||
| − | + | Else | |
| − | + | pl.Stop() | |
| − | + | pl.Close() | |
| − | + | Me.Close | |
| − | + | Endif | |
| + | |||
| + | End | ||
| + | |||
| + | Public Sub Pipeline_Position() | ||
| + | |||
| + | Me.Title = "Tempo trascorso: " & Format(pl.Position, "0.00") | ||
| + | |||
| + | End | ||
| − | + | Public Sub Pipeline_Event(Message As MediaMessage) | |
Dim can, b As Byte | Dim can, b As Byte | ||
| Riga 253: | Riga 261: | ||
Endif | Endif | ||
| − | + | End | |
Versione attuale delle 10:06, 24 mag 2023
Mediante le Classi "MediaPipeline" e "MediaControl" del Componente gb.media e usando il plug-ig "Level" di GStreamer è possibile analizzare il valore RMS, il picco e il decay dei dati audio di un file audio, mentre esso viene eseguito.
Indice
Catturando i dati audio digitali provenienti dalla scheda audio
Mostriamo un codice in ambiente grafico catturando i dati audio provenienti da una sorgente esterna:
Private pl As MediaPipeline
Private tb As ToggleButton
Private gv As GridView
Public Sub _new()
With Me
.W = 600
.H = 300
End With
With gv = New GridView(Me)
.X = 10
.Y = 10
.W = Me.W - 20
.H = Me.H * 0.6
.Columns.Count = 2
.Columns.Width = gv.w / 2
.Rows.Count = 6
End With
With tb = New ToggleButton(Me) As "Tasto"
.Y = Me.H * 0.7
.W = 80
.H = 40
.X = (Me.W / 2) - (.W / 2)
.Text = "Start"
End With
End
Public Sub Form_Open()
Dim src, con, lev, snk As MediaControl
pl = New MediaPipeline As "Pipeline"
src = New MediaControl(pl, "alsasrc")
con = New MediaControl(pl, "audioconvert")
lev = New MediaControl(pl, "level")
snk = New MediaControl(pl, "alsasink")
src.LinkTo(con)
con.LinkTo(lev)
lev.LinkTo(snk)
End
Public Sub Tasto_Click()
If tb.Value Then
pl.Play()
tb.Text = "Stop"
Else
pl.Stop()
pl.Close()
Me.Close
Endif
End
Public Sub Pipeline_Event(Message As MediaMessage)
Dim can, b As Byte
Dim rms As Float
If Message.Name = "level" Then
For can = 0 To Message[Message.Keys[5]].count - 1 ' Numero canali
gv[0, can].RichText = "<B>Canale " & CStr(can + 1)
gv[1, can].Text = Message.Keys[0] & " " & CStr(Time(0, 0, 0, Message[Message.Keys[can]] / 1000000))
For b = 5 To Message.count - 1
With Message
gv[b - 3, can].Text = CStr(.Keys[b]) & ": " & CStr(Message[.Keys[b]][can])
End With
If b = 5 Then
rms = (10 ^ (Message[Message.Keys[b]][can] / 20))
gv[5, can].Text = "Valore rms normalizzato: " & CStr(rms)
Endif
Next
Next
Endif
End
Eseguendo file audio
Mostriamo dei codici in ambiente grafico eseguendo rispettivamente un file WAV, un file Mp3 e un file OGG.
Eseguendo un file audio WAV
Private pl As MediaPipeline
Private tb As ToggleButton
Private gv As GridView
Public Sub _new()
With Me
.W = 600
.H = 300
End With
With gv = New GridView(Me)
.X = 10
.Y = 10
.W = Me.W - 20
.H = Me.H * 0.6
.Columns.Count = 2
.Columns.Width = gv.w / 2
.Rows.Count = 6
End With
With tb = New ToggleButton(Me) As "Tasto"
.Y = Me.H * 0.7
.W = 80
.H = 40
.X = (Me.W / 2) - (.W / 2)
.Text = "Start"
End With
End
Public Sub Form_Open()
Dim src, par, con, lev, snk As MediaControl
pl = New MediaPipeline As "Pipeline"
src = New MediaControl(pl, "filesrc")
src["location"] = "/percorso/del/file.wav"
par = New MediaControl(pl, "wavparse")
con = New MediaControl(pl, "audioconvert")
lev = New MediaControl(pl, "level")
snk = New MediaControl(pl, "alsasink")
src.LinkTo(par)
par.LinkTo(con)
con.LinkTo(lev)
lev.LinkTo(snk)
End
Public Sub Tasto_Click()
If tb.Value Then
pl.Play()
tb.Text = "Stop"
Else
pl.Stop()
pl.Close()
Me.Close
Endif
End
Public Sub Pipeline_Event(Message As MediaMessage)
Dim can, b As Byte
Dim rms As Float
If Message.Name = "level" Then
For can = 0 To Message[Message.Keys[5]].count - 1 ' Numero canali"
gv[0, can].RichText = "<B>Canale " & CStr(can + 1)
gv[1, can].Text = Message.Keys[0] & " " & CStr(Time(0, 0, 0, Message[Message.Keys[can]] / 1000000))
For b = 5 To Message.count - 1
With Message
gv[b - 3, can].Text = CStr(.Keys[b]) & ": " & CStr(Message[.Keys[b]][can])
End With
If b = 5 Then
rms = (10 ^ (Message[Message.Keys[b]][can] / 20))
gv[5, can].Text = "Valore rms normalizzato: " & CStr(rms)
Endif
Next
Next
Endif
End
Eseguendo un file audio MP3
Per utilizzare il precedente codice con un file audio di formato MP3, è sufficiente sostituire un paio di elementi MediaControl come segue:
par = New MediaControl(pl, "mpegaudioparse") con = New MediaControl(pl, "mpg123audiodec")
Eseguendo un file audio OGG
Per utilizzare il precedente codice con un file audio di formato OGG, si utilizzerà un codice simile al precedente con qualche variazione:
Private pl As MediaPipeline
Private gv As GridView
Public Sub _new()
With Me
.W = 600
.H = 200
End With
With gv = New GridView(Me)
.X = 10
.Y = 10
.W = Me.W - 20
.H = Me.H * 0.8
.Columns.Count = 2
.Columns.Width = gv.w / 2
.Rows.Count = 6
End With
End
Public Sub Tasto_Click()
If tb.Value Then
Dim src, par, con, lev, snk As MediaControl
pl = New MediaPipeline As "Pipeline"
src = New MediaControl(pl, "filesrc")
src["location"] = "/percorso/del/file.ogg"
par = New MediaControl(pl, "oggdemux")
con = New MediaControl(pl, "vorbisdec")
lev = New MediaControl(pl, "level")
snk = New MediaControl(pl, "alsasink")
src.LinkTo(par)
par.LinkLaterTo(con)
con.LinkTo(lev)
lev.LinkTo(snk)
pl.Play()
Wait pl.Duration
pl.Close
Else
pl.Stop()
pl.Close()
Me.Close
Endif
End
Public Sub Pipeline_Position()
Me.Title = "Tempo trascorso: " & Format(pl.Position, "0.00")
End
Public Sub Pipeline_Event(Message As MediaMessage)
Dim can, b As Byte
Dim rms As Float
If Message.Name = "level" Then
For can = 0 To Message[Message.Keys[5]].count - 1 ' Numero canali"
gv[0, can].RichText = "<B>Canale " & CStr(can + 1)
gv[1, can].Text = Message.Keys[0] & " " & CStr(Time(0, 0, 0, Message[Message.Keys[can]] / 1000000))
For b = 5 To Message.count - 1
With Message
gv[b - 3, can].Text = CStr(.Keys[b]) & ": " & CStr(Message[.Keys[b]][can])
End With
If b = 5 Then
rms = (10 ^ (Message[Message.Keys[b]][can] / 20))
gv[5, can].Text = "Valore rms normalizzato: " & CStr(rms)
Endif
Next
Next
Endif
End
