audiobuffer.h

本程序为ST公司开发的源代码

/**************************************************
 *
 * audiobuffer.h
 *
 * CVS ID:   $Id: audiobuffer.h,v 1.26 2007/01/30 13:57:02 marcucci Exp $
 * Author:   Raffaele Belardi [RB] - STM
 * Date:     $Date: 2007/01/30 13:57:02 $
 * Revision: $Revision: 1.26 $
 * 
 * Description:
 * 
 * API for AudioBuffer access
 * 
 ***************************************************
 * 
 * COPYRIGHT (C) ST Microelectronics  2005
 *            All Rights Reserved
 *
 ***************************************************
 *
 *  \brief        Audio buffer
 *
 *  \par          Change History:
 *
 * - BB060926a    Fixed CD exchange (WUT74-18-102531)
 *
 ******************************************************************************
 *
 * STM CVS Log:
 *
 * $Log: audiobuffer.h,v $
 * Revision 1.26  2007/01/30 13:57:02  marcucci
 * 16/32 SRC run-time selection
 *
 * Revision 1.25  2006/11/02 12:10:33  chlapik
 * - checked all global variables used by DMA CH0 interrupt and DEC or CTR task - disable/enable scheduling/interrupts used for protection
 * - functions AudioBufferResetPosition() and ResetAudioBuffer() check if DMA xfer is not active, only then do the modification of AB variables
 * - CDDA - repeat of last xfer:
 * 		- mark AB element used for repeat xfer as not empty in order that DEC doesn't reconfigure SRC, DMA, OIF
 * 		- after repeated xfer is finished, if new data available, start DMA xfer again, but set source address correctly, not one from previous xfer
 *
 * Revision 1.24  2006/10/09 13:36:18  belardi
 * Merge of m8_cav2_cm80507 - created new AudioBufferResetPosition() function
 *
 * Revision 1.23  2006/09/18 09:55:21  belardi
 * Corrected CVS keyword usage
 *
 * Revision 1.22  2006/09/18 09:23:01  belardi
 * Added Log CVS keyword into file header
 *
 *
 ***************************************************/
#ifndef _AUDIOBUFFER_H_
#define _AUDIOBUFFER_H_

#include "configuration.h"
#include "decoder_defines.h"
#include "xdefines.h"
#include "events.h"

typedef enum AudioBufferStatus_tag {
	abDataReady,
	abEmpty,
	abTransferInProgress,
	abTransferComplete,
	abError,
	abDummy = 0xFFFF
} AudioBufferStatus;

#if (0 == HAVE_SHOCK_MEMORY)
#define AudioBufferElements			2
#endif

/* IN SAMPLES */
#if   (HAVE_WMA==0) && (HAVE_AAC==0)
 #define AUDIO_BUFFER_ELEMENT_LENGTH	(576*2)
#elif (HAVE_WMA==0) && (HAVE_AAC==1)
 #define AUDIO_BUFFER_ELEMENT_LENGTH	(2600*2)
#else /*HAVE_WMA*/
 #if (HAVE_SHOCK_MEMORY==0)
  #define AB_UNDERFLOW_LIMIT			32			// [LL]
  #define AUDIO_BUFFER_ELEMENT_LENGTH	(576*2)
 #else /*HAVE_SHOCK_MEMORY*/
  #define AB_UNDERFLOW_LIMIT			400			// [LL]
  #define AUDIO_BUFFER_ELEMENT_LENGTH	(2600*2)	//(2200*2)	// [LL]
 #endif /*HAVE_SHOCK_MEMORY*/
#endif /*HAVE_WMA*/

//#ifdef WMA_PCM32
typedef int AudioBufferData;
//#else
//typedef short AudioBufferData;
//#endif

typedef AudioBufferData *pAudioBufferData;

//[MM] Prepare AudioBuffer for SRC 16 bit interface.
//[MM] it is important to have AudioBufferData at 4 bytes 
//[MM] boundary
typedef struct AudioBuffer_tag {
// AudioBufferStatus status;
//#if (HAVE_SHOCK_MEMORY!=0)
//	AudioBufferData *data;
//#else
	AudioBufferData data[AUDIO_BUFFER_ELEMENT_LENGTH];
//#endif /*HAVE_SHOCK_MEMORY*/
  AudioBufferStatus status;
  uint32 DataLength;
  ElementFlagType ElementFlag;
  tDecoderTime_event TimeEvent;
  t_position Position;
  uint16 Bitrate;
} AudioBufferElement;


pAudioBufferData AudioBufferHaveSpace(eDecoderSampleRate SampleRate);
void AudioBufferInit(void);
void ResetAudioBuffer(void);
pAudioBufferData AudioBufferRead(uint32 *);
void AudioBufferSetFull(uint32 num_samples, ElementFlagType ElementFlag, tDecoderTime_event *TimeEvent, t_position *Position);
uint32 CIF_reconf(uint32 enable);
void start_dma0_xfer(void);
t_position AB_GetPlayedPosition(void);
uint32 AB_GetPlayedOffset(void);
t_XItem AB_GetPlayedXfile(void);
t_position AB_GetCurrentPosition(void);
uint16 AB_GetPlayedBitrate(void);
uint16 AB_GetCurrentBitrate(void);

void AudioBufferResetPosition(void);  /* BB060926a */

#if (0 == HAVE_SHOCK_MEMORY)
extern AudioBufferElement AudioBuffer[];
#else
extern AudioBufferElement *AudioBuffer;     //[MM]
extern uint32 AudioBufferElements;          //[MM]
#endif

extern volatile int g_ABempty;
extern volatile short g_AudioBufferReadFrom;

#endif //_AUDIOBUFFER_H_