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-- Programmed by Jedidiah Barber
-- Released into the public domain
with
Ada.Numerics.Long_Elementary_Functions,
Ada.Text_IO,
Interfaces,
Portaudio.Streams;
procedure Sine_Block is
package Num renames Ada.Numerics;
package Elem renames Ada.Numerics.Long_Elementary_Functions;
package TIO renames Ada.Text_IO;
package Paud renames Portaudio;
package Pstm renames Portaudio.Streams;
Play_Time : constant Paud.Time := 5.0;
Sample_Rate : constant Paud.Hertz := 44100.0;
Channels : constant Natural := 2;
Per_Buffer : constant Pstm.Frame_Amount := 1024;
-- Note how this array specifies the bounds in the initial value rather than the type.
-- This is important because otherwise the aliasing would cause subtype mismatch errors.
Sample_Array : aliased Pstm.Float_32_Array := (1 .. Natural (Per_Buffer) * Channels => 0.0);
Sample_Buffer : constant Pstm.Buffer := Pstm.Wrap (Sample_Array, Per_Buffer, Channels);
type Table_Index is mod 200;
Sine_Table : array (Table_Index) of Interfaces.IEEE_Float_32;
Left_Phase, Right_Phase : Table_Index := 0;
Left_Increment : Table_Index := 1;
Right_Increment : Table_Index := 3;
Buffer_Count : Natural;
Sine_Stream : Pstm.Audio_Stream;
begin
TIO.Put_Line ("PortAudio Test: output sine wave. " &
"Sample Rate = " & Paud.Hertz_Image (Sample_Rate) & ", " &
"Buffer Size =" & Pstm.Frame_Amount'Image (Per_Buffer));
for Index in Table_Index loop
Sine_Table (Index) := Interfaces.IEEE_Float_32
(Elem.Sin (Long_Float (Index) / Long_Float (Table_Index'Last_Valid) * Num.Pi * 2.0));
end loop;
Sine_Stream.Open_Default_Blocking
(Input_Channels => 0,
Output_Channels => Channels,
Format => Pstm.Float_32_Format,
Sample_Rate => Sample_Rate,
Buffer_Frames => Per_Buffer);
TIO.Put_Line ("Play 3 times, higher each time.");
for Round in Integer range 1 .. 3 loop
TIO.Put_Line ("Play for " & Paud.Image (Play_Time) & " seconds.");
Sine_Stream.Start;
Buffer_Count := Integer (Play_Time) * Integer (Sample_Rate) / Integer (Per_Buffer);
for Fill in Integer range 1 .. Buffer_Count loop
for Index in Pstm.Frame_Amount range 1 .. Per_Buffer loop
Sample_Buffer.Put (Index, 1, Sine_Table (Left_Phase));
Sample_Buffer.Put (Index, 2, Sine_Table (Right_Phase));
Left_Phase := Left_Phase + Left_Increment;
Right_Phase := Right_Phase + Right_Increment;
end loop;
Sine_Stream.Write_Blocking (Sample_Buffer, Per_Buffer);
end loop;
Sine_Stream.Stop;
Left_Increment := Left_Increment + 1;
Right_Increment := Right_Increment + 1;
delay 1.0;
end loop;
Sine_Stream.Close;
TIO.Put_Line ("Test finished.");
end Sine_Block;
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