wtaudiorecord.c

来自「MCF5249的音频驱动程序,可以实现PCM的实时播放和采集」· C语言 代码 · 共 984 行 · 第 1/2 页

    337, 371, 408, 449, 494, 544, 598, 658, 724, 796,
    876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
    2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,
    5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
    15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
};

typedef struct adpcm_state{
	int index;
	int valprev;
}_ADPCM,*pADPCM;

void
adpcm_coder(short *indata, unsigned char *outdata, int len, struct adpcm_state *state)
{
    short *inp;			/* Input buffer pointer */
    signed char *outp;		/* output buffer pointer */
    int val;			/* Current input sample value */
    int sign;			/* Current adpcm sign bit */
    int delta;			/* Current adpcm output value */
    int diff;			/* Difference between val and valprev */
    int step;			/* Stepsize */
    int valpred;		/* Predicted output value */
    int vpdiff;			/* Current change to valpred */
    int index;			/* Current step change index */
    int outputbuffer;		/* place to keep previous 4-bit value */
    int bufferstep;		/* toggle between outputbuffer/output */

    outp = (signed char *)outdata;
    inp = indata;

    valpred = state->valprev;
    index = state->index;
    step = stepsizeTable[index];
    
    bufferstep = 1;
    

    for ( ; len > 0 ; len-- ) {
	val = *inp++;

	/* Step 1 - compute difference with previous value */
	diff = val - valpred;
	sign = (diff < 0) ? 8 : 0;
	if ( sign ) diff = (-diff);

	/* Step 2 - Divide and clamp */
	/* Note:
	** This code *approximately* computes:
	**    delta = diff*4/step;
	**    vpdiff = (delta+0.5)*step/4;
	** but in shift step bits are dropped. The net result of this is
	** that even if you have fast mul/div hardware you cannot put it to
	** good use since the fixup would be too expensive.
	*/
	delta = 0;
	vpdiff = (step >> 3);
	
	if ( diff >= step ) {
	    delta = 4;
	    diff -= step;
	    vpdiff += step;
	}
	step >>= 1;
	if ( diff >= step  ) {
	    delta |= 2;
	    diff -= step;
	    vpdiff += step;
	}
	step >>= 1;
	if ( diff >= step ) {
	    delta |= 1;
	    vpdiff += step;
	}

	/* Step 3 - Update previous value */
	if ( sign )
	  valpred -= vpdiff;
	else
	  valpred += vpdiff;

	/* Step 4 - Clamp previous value to 16 bits */
	if ( valpred > 32767 )
	  valpred = 32767;
	else if ( valpred < -32768 )
	  valpred = -32768;

	/* Step 5 - Assemble value, update index and step values */
	delta |= sign;
	
	index += indexTable[delta];
	if ( index < 0 ) index = 0;
	if ( index > 88 ) index = 88;
	step = stepsizeTable[index];

	/* Step 6 - Output value */
	if ( bufferstep ) {
	    outputbuffer = (delta & 0x0f) ; 
	} else {
	    *outp++ = ((delta << 4) & 0xf0) | outputbuffer;
	}
	bufferstep = !bufferstep;
    }

    /* Output last step, if needed */
    if ( !bufferstep )
      *outp++ = outputbuffer;
    
    state->valprev = valpred;
    state->index = index;
}

void
adpcm_decoder(char *indata, short *outdata,int len, struct adpcm_state* state)    
{
    signed char *inp;		/* Input buffer pointer */
    short *outp;		/* output buffer pointer */
    int sign;			/* Current adpcm sign bit */
    int delta;			/* Current adpcm output value */
    int step;			/* Stepsize */
    int valpred;		/* Predicted value */
    int vpdiff;			/* Current change to valpred */
    int index;			/* Current step change index */
    int inputbuffer;		/* place to keep next 4-bit value */
    int bufferstep;		/* toggle between inputbuffer/input */

    outp = outdata;
    inp = (signed char *)indata;

    valpred = state->valprev;
    index = state->index;
    step = stepsizeTable[index];

    bufferstep = 0;
    
    for ( ; len > 0 ; len-- ) {
	
	/* Step 1 - get the delta value */
	if ( bufferstep ) {
	    delta = inputbuffer & 0xf;
	} else {
	    inputbuffer = *inp++;
	    delta = (inputbuffer >> 4) & 0xf;
	}
	bufferstep = !bufferstep;

	/* Step 2 - Find new index value (for later) */
	index += indexTable[delta];
	if ( index < 0 ) index = 0;
	if ( index > 88 ) index = 88;

	/* Step 3 - Separate sign and magnitude */
	sign = delta & 8;
	delta = delta & 7;

	/* Step 4 - Compute difference and new predicted value */
	/*
	** Computes 'vpdiff = (delta+0.5)*step/4', but see comment
	** in adpcm_coder.
	*/
	vpdiff = step >> 3;
	if ( delta & 4 ) vpdiff += step;
	if ( delta & 2 ) vpdiff += step>>1;
	if ( delta & 1 ) vpdiff += step>>2;

	if ( sign )
	  valpred -= vpdiff;
	else
	  valpred += vpdiff;

	/* Step 5 - clamp output value */
	if ( valpred > 32767 )
	  valpred = 32767;
	else if ( valpred < -32768 )
	  valpred = -32768;

	/* Step 6 - Update step value */
	step = stepsizeTable[index];

	/* Step 7 - Output value */
	*outp++ = valpred;
    }

    state->valprev = valpred;
    state->index = index;
}

void upcm_encode(unsigned char *indata, unsigned char * outdata, int len)
{
	unsigned int i=0;
	unsigned short *src = (unsigned short *)indata;	
	for(;i<(len/2);i++)
		outdata[i] = linear2ulaw(src[i]);
}

void a2u_encode(unsigned char *indata, unsigned char *outdata, int len)
{
	int i=0;
	for(;i<len;i++)
		outdata[i] = alaw2ulaw(indata[i]);
}

static inline short adpcm_ima_expand_nibble(char nibble,pADPCM state)
{
	int index;
	int valprev;
	int sign, delta, diff, step;

	step = stepsizeTable[state->index];
	index = state->index + indexTable[(unsigned)nibble];
	if (index < 0) index = 0;
	else if (index > 88) index = 88;

	sign = nibble & 8;
	delta = nibble & 7;
	/* perform direct multiplication instead of series of jumps proposed by
	* the reference ADPCM implementation since modern CPUs can do the mults
	* quickly enough */
	diff = ((2 * delta + 1) * step) >> 3;
	/*
	
	diff = step >> 3;
	if ( delta & 4 ) diff += step;
	if ( delta & 2 ) diff += step>>1;
	if ( delta & 1 ) diff += step>>2;
	*/

	valprev = state->valprev;
	if (sign) valprev -= diff;
	else valprev += diff;

	CLAMP_TO_SHORT(valprev);
	state->valprev = valprev;
	state->index = index;

	return (short)valprev;
}




void ad2u_Send(void* indata, OUTDATA_T* outdata, int nSrcSize, BYTE* private )
{
	//short *samples;
	long *samples;
	unsigned char *src;
	pADPCM state;
	short tmp;

	state = (pADPCM)private;
	samples = (long *)outdata; //dest
	src = (unsigned char *)indata;      //src

    
	state->valprev = (*src++) & 0x0FF;
	state->valprev |= ((*src++) << 8) & 0x0FF00;
	if(state->valprev & 0x8000)
		state->valprev -= 0x10000;
	CLAMP_TO_SHORT(state->valprev);

	//*samples++ = state->valprev;	
	*samples++ = (linear2ulaw(state->valprev)<<24)&0xff000000;

	state->index = *src++;
	if (state->index < 0) state->index = 0;
	if (state->index > 88) state->index = 88;
	*src++;
	//if (*src++) fprintf(stderr, "unused byte should be null !!\n"); 

	
	for(; src < ((unsigned char *)indata + nSrcSize);) 
	{
		//*samples++ = adpcm_ima_expand_nibble(src[0] & 0x0F,state);				
		*samples++ = (linear2ulaw(adpcm_ima_expand_nibble(src[0] & 0x0F,state))<<24)&0xff000000;
		//*samples++ = adpcm_ima_expand_nibble((src[0] >> 4) & 0x0F,state);		 		
		*samples++ = (linear2ulaw(adpcm_ima_expand_nibble((src[0] >> 4) & 0x0F,state))<<24)&0xff000000;		
		src++;
	}
	//*pDestSize = (unsigned char *)samples - (unsigned char *)outdata;
	return;

}

void ulaw_Send(void* indata, OUTDATA_T* outdata, int nSrcSize, BYTE* private )
{
	unsigned char* src = (unsigned char *)indata;
	while(nSrcSize--){
		*outdata++ = (*src<<24);
		src++;		
	}
}

unsigned long ad2ulaw(short indata, struct adpcm_state *state)
{
	int sign;			/* Current adpcm sign bit */
    	int delta;			/* Current adpcm output value */
    	int step;			/* Stepsize */
    	int valpred;		/* Predicted value */
    	int vpdiff;			/* Current change to valpred */
    	int index;			/* Current step change index */
  //unsigned char Intmp[4],Outtmp[4];
	int i;
	unsigned long outdata=0;
 
	valpred = state->valprev;
 	 index = state->index;  

	for(i=3; i>=0; i--){
		
		//delta = (indata>>4*i)&0x0f;
		if(i == 3)
			delta = indata>>8;
		else if(i == 2)
			delta = indata>>12;
		else if(i == 0)
			delta = indata>>4;
		else
			delta = indata;
		delta &= 0x0f;
		//printf("delta[%d] = 0x%02x\n",i,delta);
		
    step = stepsizeTable[index];

		index += indexTable[delta];
		if ( index < 0 ) index = 0;
		if ( index > 88 ) index = 88;

		sign = delta & 8;
		delta = delta & 7;

		vpdiff = step >> 3;
		if ( delta & 4 ) vpdiff += step;
		if ( delta & 2 ) vpdiff += step>>1;
		if ( delta & 1 ) vpdiff += step>>2;

		if ( sign )
	  		valpred -= vpdiff;
		else
	  		valpred += vpdiff;

		if ( valpred > 32767 )
	  		valpred = 32767;
		else if ( valpred < -32768 )
	  		valpred = -32768;

		//printf("valpred = 0x%04x\n",valpred);
		outdata |= (linear2ulaw(valpred)<<(8*i));
		//printf("outdata =0x%04x\n",outdata);
	}
	//printf("outdata =0x%04x\n",outdata);

	state->valprev = valpred;
    	state->index = index;
	return outdata;	
}

int Audio_encode(unsigned char *indata, unsigned char * outdata, int len, int coding_type,struct adpcm_state *state)
{
	unsigned char *pBuf;
	int i;
	unsigned short * pInData;
	unsigned long *pOutData;
	pInData = (unsigned short *)indata;
	pOutData = (unsigned long *)outdata;
	switch(coding_type) {
	case AUDIO_ENCODING_ADPCM:
		for(i=0; i<len; i++){			
			*pOutData ++ = ad2ulaw(*pInData++,state);			
		}
		//adpcm_decoder(indata,(short *)pBuf,len,&state);
		//upcm_encode(pBuf,outdata,len*4);
		//free(pBuf);
		break;
	case AUDIO_ENCODING_LINEAR:
		upcm_encode(indata,outdata,len);
		break;
	case AUDIO_ENCODING_ALAW:
		a2u_encode(indata, outdata, len);
	case AUDIO_ENCODING_ULAW:
		while (len--){ 
			*outdata++ = *indata++;
			//printf("%x ",*outdata);
		}
	default:
		return -1; 		
	}
	return 0;
}




void mySig(void (*fun)(int))
{
	struct sigaction act;   
	act.sa_handler = fun;   
	sigemptyset(&act.sa_mask);   
	act.sa_flags=0;

	sigaction(SIGTERM,&act,NULL);  
  	sigaction(SIGHUP,&act,NULL);  
  	sigaction(SIGINT,&act,NULL);  
  	sigaction(SIGQUIT,&act,NULL);  
  	sigaction(SIGUSR1,&act,NULL);  
  	sigaction(SIGUSR2,&act,NULL); 
	
}

void myExit(int signo)
{
	//I6400WriteMem(0x2000,0x2);//Stop
	//munmap(VBuffer,VIDEOBUFSIZE);
	//munmap(ABuffer,AUDIOBUFSIZE);	
	//munmap(VU_Stream.srcBuffer,VIDEOBUFSIZE);
	//munmap(VU_Stream.srcBuffer,APACKCOUNT*AU_Stream.nOutPSize);
		
//	AudioDelay(1);
	
	//close(VideoIN);
	close(AudioID);	
	printf("exit()_signo[%d]\n",signo);
	//alarm(0);
	//raise(signo);
	exit(1);
}


/************************************************/
/* Example too the audio playback*/



int main()
{
	BYTE *pDataIN; //input  audio data	
	DWORD *pDataOUT;
	_ADPCM state;
	int coding;	
	int nSaveFile;
	int nr,nw;
	
	
	mySig(myExit);  //safe exit

	state.index = 0;
	state.valprev = 0;

	AudioID = open("/dev/WTAUDIO",O_RDWR );
	if(AudioID  == -1)
	{
		printf("Can not open /dev/WTAUDIO .\n");
		exit(0);
	}	

	nSaveFile = open("../audio.raw",O_RDWR |O_CREAT);

	if(nSaveFile == -1)
	{	
		printf("Can't creat ../audio.raw\n");
		exit(0);
	}

	pDataOUT = (DWORD*)malloc(sizeof(int)*508);

	
 
	while(1)
	{

#ifdef AUDIO_RECODE
	nr = read(AudioID, pDataOUT, sizeof(int)*508);
	if(nr != 508)
		printf("read error\n");

	nw = write(nSaveFile, pDataOUT, sizeof(int)*508);
	if(nw != 508)
		printf("read error\n");
	
#endif
	
	}
	


	close(AudioID);	
	return 0;
}