Re: Ada and MidiShare

[tmoran@acm.org]

>It seems that Claw supports at least audio, but that is only for Windows.
>The audio support I'd want is very simple, just buffered streams to/from
>the audio inputs/outputs for realtime recording and playback.

Claw multimedia audio under Windows includes things like:

For simple buffered Stream IO:
  type Stream_Type(Channel_Count : Channel_Counts;
                   Byte_Depth    : Byte_Depths;
                   Sample_Rate, Length : CLAW.DWord;
                   Buffer_Count : Buffer_Counts)
  is new Ada.Streams.Root_Stream_Type with private;

  procedure Open_Output(Stream : in out Stream_Type;
                        Playing_Device : in Playing_Device_ID_Type);

  procedure Write(Stream : in out Stream_Type;
                  Item   : in     Ada.Streams.Stream_Element_Array);

  procedure Close(Stream : in out Stream_Type);

For buffered IO with structured data (ie, Mono8_Wave_Type,
Stereo16_Wave_Type, etc):

  type Mono8_Stream_Type(Sample_Rate, Length : CLAW.DWord;
                         Buffer_Count : Buffer_Counts)
  is new Stream_Type with private;

  procedure Mono8_Wave_Type_Read(Stream : access Ada.Streams.Root_Stream_Type'class;
                                 Item   :    out Mono8_Wave_Type);

  procedure Mono8_Wave_Type_Write(Stream : access Ada.Streams.Root_Stream_Type'class;
                                  Item   : in     Mono8_Wave_Type);

For asynchronous IO, where you get a callback on each buffer load:

  type Async_Type(Channel_Count : Channel_Counts;
                  Byte_Depth    : Byte_Depths;
                  Sample_Rate, Length : CLAW.DWord;
                  Buffer_Count : Buffer_Counts)
  is abstract new Ada.Finalization.Limited_Controlled with private;

  procedure When_Listen(Async : in out Mono8_Async_Type;
                        Sound : in     Mono8_Wave_Type) is abstract;
  -- User supplied routine, called with each buffer load of incoming sound.

  procedure When_Say(Async : in out Mono8_Async_Type;
                     Sound :    out Mono8_Wave_Type) is abstract;
  -- User supplied routine, called to get sound for outgoing buffer.

etc.