/*

    File:       IMAAudioQueue.h

    Contains:   Delcaration of IMAAudioQueue, a queue datatype for IMA

                audio sample data.

    Copyright:  © 1997-1999 by Apple Computer, Inc., all rights reserved.

    The IMAAudioQueue serves several functions:

        -   it internally copies and disposes of RTPMPSampleDataParams

            data structures

        -   it converts from the descriptions of arbitrarily large sample

            blocks, given in RTPMPSampleDataParams data structures, to

            descriptions of single frames

        -   it can convert incoming data to a lower sample rate by dropping

            frames as necessary

*/

#ifndef __IMAAUDIOQUEUE__

#define __IMAAUDIOQUEUE__

#pragma once

#include "TQueue.h"

#include <QTStreamingComponents.h>

typedef struct IMAAudioQueueElement

{

    TimeValue64                 itsTimestamp;

    UInt32                      itsChannel;

    RTPMPSampleDataParams *     itsSampleDataParams;

    UInt32                      itsOffset;

} IMAAudioQueueElement;

typedef struct IMAAudioQueue

{

    TQueue          __itsQueue;

    TimeValue64     __itsStartTime;

    UInt32          __itsFrameCount;

    UInt32          __itsCurrentOffset;

    UInt32          __itsConsumedFrameCount;

    UInt32          __itsDequeuedFrameCount;

    UnsignedFixed   __itsIncomingSampleRate;

    UnsignedFixed   __itsOutgoingSampleRate;

    UInt16          __itsChannelCount;

} IMAAudioQueue;

extern

void

IMAAudioQueueInitialize(

    IMAAudioQueue *     inQueue );

extern

UnsignedFixed

IMAAudioQueueSetFlowControl(

    IMAAudioQueue *     inQueue,

    UnsignedFixed       inIncomingSampleRate,

    UnsignedFixed       inOutgoingSampleRate,

    UInt16              inChannelCount );

extern

UInt32

IMAAudioQueueCount(

    const IMAAudioQueue *   inQueue );

extern

RTPMPSampleDataParams *

IMAAudioQueueEnqueue(

    IMAAudioQueue *                 inQueue,

    const RTPMPSampleDataParams *   inSampleDataParams );

extern

Boolean

IMAAudioQueueDequeue(

    IMAAudioQueue *         inQueue,

    IMAAudioQueueElement *  outElement );

extern

void

IMAAudioQueueFlush(

    IMAAudioQueue *     inQueue );

#endif /* __IMAAUDIOQUEUE__ */