fmad.h

embedded linux 下MP3的解码程序

//****************************************************************************
// 
// Faraday Technology Coporation 
// Copyright (C) Microsoft Corporation. All rights reserved.
//                                
//*--------------------------------------------------------------------------*
//* Name:FMAD.h                                                              *
//* Description: MPEG-1/2 Audio Layer 3 Decoder API definition               *
//* Author: Shawn, Hsiao                                                     *
//* Date: 2006/06/06                                                         *
//* Version:1.0	                                                             *
//****************************************************************************

#ifndef FMP3D_H_INCLUDED
#define FMP3D_H_INCLUDED

struct MP3dec_info;

//============================================================================
//        Definition                                
//============================================================================

//******************************************************************************
// 
#define IN_SIZE 1024     
//
//******************************************************************************  
//
// Define input buffer size as 1024
//
//******************************************************************************

//******************************************************************************
// 
#define OUT_SIZE 4608    
//
//******************************************************************************  
//
// Define output buffer size as 4608
//
//******************************************************************************

//******************************************************************************
// 
#define FARADAY_EQ     
//
//******************************************************************************  
//
// If define this term, the Equalizer (EQ) is inserted.
//
//******************************************************************************

//******************************************************************************
// 
#define DISPLAYSET_MP3DEC_BY_FRAME     
//
//******************************************************************************  
//
// If define this term, the decoder will call call-back function 
// "DisplaySet_MP3dec_type" once in a frame. Decoder may give response
// frequently. It might consume more computing power because the function is calling.
// If non-define, the default case is once per input data.
//
//******************************************************************************

//******************************************************************************
//
#define DISPLAY_AACDEC_INFO
//
//******************************************************************************  
//
// If define this term, the decoder will get AAC decoder information. 
//
//******************************************************************************

//******************************************************************************
//
#define DISPLAY_TIME_INFO
//
//******************************************************************************  
//
// If define this term, the decoder will get time information. 
//
//******************************************************************************

//============================================================================
//        Call-back function type define                                
//============================================================================

//******************************************************************************
// 
typedef int (*OutputPCM_type)(char *, int, int);
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> output buffer pointer 
// parameter 2 -> output data size in bytes 
// parameter 3 -> output file ("0" means no file output)
// output: data size which is really output in bytes
//
// This call-back function is called when decoder decoded one frame data.
// For the case of MP3 decoder, the data in one frame is fixed to 9216 bytes
// (32-bits output sample) or 4608 bytes (16-bits output sample).
// It is suggested that when the function is called, the main program must 
// get all output samples at once. Otherwise, the decoder will keep calling
// until all output samples are got.
// The correct  size of output data, which is really got from output buffer, must be 
// given to make sure the decoder works normally.
//
//******************************************************************************

//******************************************************************************
// 
typedef int (*InputData_type)(char *, int, int);	
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> input buffer pointer
// parameter 2 -> input size
// parameter 3 -> input file ("0" means no file input)
// output: data size which is really input in bytes
//
// This call-back function is called when decoder needs more data to input buffer.
// The decoder gives an expected data size and a pointer, which the data must be placed at.
// The correct  size of input data, which is really placed to input buffer, must be 
// given to make sure the decoder works normally.
//
//******************************************************************************

//******************************************************************************
// 
typedef int (*DataSeek_type)(int, int, int);     
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> data seek size
// parameter 2 -> seek type 0: seek from start, 1: seek from current, 2: seek from end
// parameter 3 -> input file ("0" means no file input)
// output: error message -> 0: ok, others: fail
//
// This function is called when the decoder want to seek to some specific point in 
// the bitstream or file.
//
//****************************************************************************** 

//******************************************************************************
// 
typedef void (*DisplaySet_MP3dec_type)(struct MP3dec_info *);
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> MP3 decoder information pointer
// output: NA
//
// This function is called when the decoder can serve the display and set process.
// It can be defined 1) once per frame, or 2) once per input data.
// If the program does not need to display or set, this function must be sure as
// an empty function. Otherwise, it may does some unpredictable processing.
//
//******************************************************************************

//============================================================================
//        Data structure                                
//============================================================================
 
//******************************************************************************
// 
// struct MP3dec_info
//  
//******************************************************************************
//            
// This structure defines all MP3 decoder information with elements:
// 1) input_file: save the input file pointer. If no one, set it "0".
// 2) output_file: save the output file pointer. If no one, set it "0".
// 3) input_buf: save the pointer of input buffer.
// 4) output_buf: save the pointer of output buffer.
// 5) layer: information of layer.
// 6) bit_rate: information of bit rate.
// 7) sampling_frequency: information of sampling rate.
// 8) mode: information of channel mode -> 0: mono, 1: stereo.
// 9) mode_ext: information of extension channel mode.
// 10) EQ: information of EQ mode.
// 11) count: information of timer -> bits[31:26] is minute, bits[25:20] is second, 
//                                    bits[19:0] is counter which is used to count sum of output samples.
// 12) InputData_type: callback function.
// 13) OutputPCM_type: callback function.
// 14) DataSeek_type: callback function.
// 15) DisplaySet_MP3dec_type: callback function.
// 
//******************************************************************************     

struct MP3dec_info
{
	int input_file;			        							// input file
	int output_file;		        							// output file
	char *input_buf;		        							// input buffer
	char *output_buf;		        							// ouput buffer
	int layer;			        									// layer information
	int bit_rate;			        								// bit rate information
	int sampling_frequency;		        				// sampling rate information
	int mode;			        										// channel mode information
	int mode_ext;			        								// extension channel mode information
	int EQ;				        										// equalizer mode
	unsigned int count;		        						// [6-bits, 6-bits, 20-bits] = [minute, second, count]
	InputData_type InputData;	        				// call-back function	
	OutputPCM_type OutputPCM;	        				// call-back function
	DataSeek_type DataSeek;                 	// call-back function
	DisplaySet_MP3dec_type DisplaySet_MP3dec; // call-back function		
};

//============================================================================
//        Functions                                
//============================================================================

//******************************************************************************
// 
int init_MP3dec_info(struct MP3dec_info *);
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> MP3 decoder information
// output: error message -> 0: ok, others: fail 
//
// This function is used to initialize MP3 decoder bit-stream information.
//
//****************************************************************************** 

//******************************************************************************
// 
int init_Data(struct MP3dec_info *, int, int, char *, char *);
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> MP3 decoder information
// parameter 2 -> input file pointer
// parameter 3 -> output file pointer
// parameter 4 -> input buffer pointer
// parameter 5 -> output buffer pointer
// output: error message -> 0: ok, others: fail 
// 
// This function  is used to set all data information.
//
//******************************************************************************

//******************************************************************************
// 
int init_CallbackFunction(struct MP3dec_info *, InputData_type, OutputPCM_type, DataSeek_type, DisplaySet_MP3dec_type);
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> MP3 decoder information.
// parameter 2 -> Input data function pointer
// parameter 3 -> Output PCM function pointer
// parameter 4 -> Data seek function pointer
// parameter 5 -> Display and set function pointer
// output: error message -> 0: ok, others: fail 
//
// This function is used to set all call-back functions. 
//
//******************************************************************************

//******************************************************************************
// 
int set_Faraday_EQ(int);
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> EQ mode
// output: EQ mode which is set
//
// This function is used to set Faraday EQ mode.
//
//****************************************************************************** 

//******************************************************************************
// 
int init_Faraday_MP3dec(struct MP3dec_info *);
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> MP3 decoder information
// output: error message -> 0: ok, 1: error 
//
// This function is used to initial MP3 Decoder. There are three steps:
// 1) Check ID3 tag. If there is one, skip it.
// 2) Find the first valid header (frame) and ignore the data before it.
// 3) Initial MP3 decoder.
//
//******************************************************************************

//******************************************************************************
// 
int do_Faraday_MP3dec(struct MP3dec_info *);
//  
//******************************************************************************
//      
// input: 
// parameter 1 -> MP3 decoder information
// output: error message -> 0: ok, 1: input data error 
//
// This function is the main decoding processing including:
// 1) input data
// 2) sync. the valid frame
// 3) decoding
// 4) output data when one frame is decoded
// 5) display and set once per frame or per input data
// 6) get time information per frame
//
//******************************************************************************

#endif //FMP3D_H_INCLUDED