imdct.c

从FFMPEG转换而来的H264解码程序,VC下编译..

	    two_m = (1 << m);
	else
	    two_m = 1;

	two_m_plus_one = (1 << (m+1));

	for(i = 0; i < 128; i += two_m_plus_one) {
	    for(k = 0; k < two_m; k++) {
		p = k + i;
		q = p + two_m;
		tmp_a_r = buf[p].real;
		tmp_a_i = buf[p].imag;
		tmp_b_r = buf[q].real * w[m][k].real - buf[q].imag * w[m][k].imag;
		tmp_b_i = buf[q].imag * w[m][k].real + buf[q].real * w[m][k].imag;
		buf[p].real = tmp_a_r + tmp_b_r;
		buf[p].imag =  tmp_a_i + tmp_b_i;
		buf[q].real = tmp_a_r - tmp_b_r;
		buf[q].imag =  tmp_a_i - tmp_b_i;
	    }
	}
    }
*/

    /* 1. iteration */
	// Note w[0][0]={1,0}
	{
	        __m128 xmm0,xmm1,xmm2;
		xorps (xmm1, xmm1);
		xorps (xmm2, xmm2);
		for (unsigned char *esi=(unsigned char*)buf;(complex_t*)esi<buf+128;esi+=16){
		    movlps (esi, xmm0);	 //buf[p]
		    movlps (8+esi, xmm1); //buf[q]
		    movhps (esi, xmm0);	 //buf[p]
		    movhps (8+esi, xmm2); //buf[q]
		    addps (xmm1, xmm0);
		    subps (xmm2, xmm0);
		    movaps (xmm0, esi);
		}
        }
    /* 2. iteration */
	// Note w[1]={{1,0}, {0,-1}}
	{
	        __m128 xmm7,xmm0,xmm1,xmm2;
		movaps (ps111_1, xmm7); // 1,1,1,-1
		for (unsigned char *esi=(unsigned char*)buf;(complex_t*)esi<buf+128;esi+=32){
		    movaps (16+esi, xmm2);	 //r2,i2,r3,i3
		    xmm2=_mm_shuffle_ps(xmm2,xmm2,0xB4);	 //r2,i2,i3,r3
		    mulps (xmm7, xmm2);		 //r2,i2,i3,-r3
		    movaps (esi, xmm0);		 //r0,i0,r1,i1
		    movaps (esi, xmm1);		 //r0,i0,r1,i1
		    addps (xmm2, xmm0);
		    subps (xmm2, xmm1);
		    movaps (xmm0, esi);
		    movaps (xmm1, 16+esi);
		}
	};

    /* 3. iteration */
/*
 Note sseW2+0={1,1,sqrt(2),sqrt(2))
 Note sseW2+16={0,0,sqrt(2),-sqrt(2))
 Note sseW2+32={0,0,-sqrt(2),-sqrt(2))
 Note sseW2+48={1,-1,sqrt(2),-sqrt(2))
*/
	{
	        __m128 xmm6,xmm7,xmm5,xmm2,xmm3,xmm4,xmm0,xmm1;
		movaps (48+(uint8_t*)sseW2, xmm6);
		movaps (16+(uint8_t*)sseW2, xmm7);
		xorps (xmm5, xmm5);
		xorps (xmm2, xmm2);
		for (unsigned char *esi=(unsigned char*)buf;(complex_t*)esi<buf+128;esi+=64){
		    movaps (32+esi, xmm2);	 //r4,i4,r5,i5
		    movaps (48+esi, xmm3);	 //r6,i6,r7,i7
		    movaps ((uint8_t*)sseW2, xmm4);	 //r4,i4,r5,i5
		    movaps (32+(uint8_t*)sseW2, xmm5); //r6,i6,r7,i7
		    mulps (xmm2, xmm4);
		    mulps (xmm3, xmm5);
		    xmm2=_mm_shuffle_ps(xmm2,xmm2,0xB1);	 //i4,r4,i5,r5
		    xmm3=_mm_shuffle_ps(xmm3,xmm3,0xB1);	 //i6,r6,i7,r7
		    mulps (xmm6, xmm3);
		    mulps (xmm7, xmm2);
		    movaps (esi, xmm0);		 //r0,i0,r1,i1
		    movaps (16+esi, xmm1);	 //r2,i2,r3,i3
		    addps (xmm4, xmm2);
		    addps (xmm5, xmm3);
		    movaps (xmm2, xmm4);
		    movaps (xmm3, xmm5);
		    addps (xmm0, xmm2);
		    addps (xmm1, xmm3);
		    subps (xmm4, xmm0);
		    subps (xmm5, xmm1);
		    movaps (xmm2, esi);
		    movaps (xmm3, 16+esi);
		    movaps (xmm0, 32+esi);
		    movaps (xmm1, 48+esi);
		}
	}

    /* 4-7. iterations */
    for (m=3; m < 7; m++) {
	two_m = (1 << m);
	two_m_plus_one = two_m<<1;
	{
	        __m128 xmm1,xmm2,xmm0;
		for (unsigned char *esi=(unsigned char*)buf;(complex_t*)esi<buf+128;esi+=two_m_plus_one<<3){
		    int edi=0;			 // k
		    for (unsigned char *edx=esi+ (two_m<<3);edi< (two_m<<3);edi+=16){
		        movaps (edx+ edi, xmm1);
		        movaps ((uint8_t*)sseW[m]+ edi* 2, xmm2);
		        mulps (xmm1, xmm2);
		        xmm1=_mm_shuffle_ps(xmm1,xmm1,0xB1);
		        mulps (16+(uint8_t*)sseW[m]+ edi* 2, xmm1);
		        movaps (esi+ edi, xmm0);
		        addps (xmm2, xmm1);
		        movaps( xmm1, xmm2);
		        addps (xmm0, xmm1);
		        subps (xmm2, xmm0);
		        movaps (xmm1, esi+ edi);
		        movaps (xmm0, edx+ edi);
		    }
		}
	}
    }

    /* Post IFFT complex multiply  plus IFFT complex conjugate*/
	{
		__m128 xmm0,xmm1;
		for (int esi=-1024;esi!=0;esi+=16){
		    movaps ((uint8_t*)(buf+128)+ esi, xmm0);
		    movaps ((uint8_t*)(buf+128)+ esi, xmm1);
		    xmm0=_mm_shuffle_ps(xmm0,xmm0,0xB1);
		    mulps (1024+(uint8_t*)sseSinCos1c+esi, xmm1);
		    mulps (1024+(uint8_t*)sseSinCos1d+esi, xmm0);
		    addps (xmm1, xmm0);
		    movaps (xmm0, (uint8_t*)(buf+128)+ esi);
		}
	}


    data_ptr = data;
    delay_ptr = delay;
    //window_ptr = imdct_window;

    /* Window and convert to real valued signal */
	{
		__m128 xmm0,xmm1,xmm2;
		movss (bias, xmm2);			  // bias
		xmm2=_mm_shuffle_ps(xmm2,xmm2,0x00);		  // bias, bias, ...
		for (int esi=0,edi=0;esi<512;esi+=16,edi-=16){
		    movlps ((uint8_t*)(buf+64)+ esi, xmm0);		 // ? ? A ?
		    movlps (8+(uint8_t*)(buf+64)+ esi, xmm1);		 // ? ? C ?
		    movhps (-16+(uint8_t*)(buf+64)+ edi, xmm1);		 // ? D C ?
		    movhps (-8+(uint8_t*)(buf+64)+ edi, xmm0);		 // ? B A ?
		    xmm0=_mm_shuffle_ps(xmm0,xmm1,0x99);// shufps $0x99, xmm1, xmm0		 // D C B A
		    mulps ((uint8_t*)sseWindow+esi, xmm0);
		    addps ((uint8_t*)delay_ptr+ esi, xmm0);
		    addps (xmm2, xmm0);
		    movaps (xmm0, (uint8_t*)data_ptr+ esi);
		}
	}
	data_ptr+=128;
	delay_ptr+=128;
//	window_ptr+=128;

	{
		__m128 xmm0,xmm1,xmm2;
		movss (bias, xmm2);			  // bias
		xmm2=_mm_shuffle_ps(xmm2,xmm2,0x00);		  // bias, bias, ...
		for (int edi=1024,esi=0;esi<512;esi+=16,edi-=16){
		    movlps ((uint8_t*)buf+ esi, xmm0);		 // ? ? ? A
		    movlps (8+(uint8_t*)buf+ esi, xmm1);		 // ? ? ? C
		    movhps (-16+(uint8_t*)buf+ edi, xmm1);		 // D ? ? C
		    movhps (-8+(uint8_t*)buf+ edi, xmm0);		 // B ? ? A
		    xmm0=_mm_shuffle_ps(xmm0,xmm1,0xCC);		 // D C B A
		    mulps (512+(uint8_t*)sseWindow+esi, xmm0);
		    addps ((uint8_t*)delay_ptr+ esi, xmm0);
		    addps (xmm2, xmm0);
		    movaps (xmm0, (uint8_t*)data_ptr+ esi);
		}
	}
	data_ptr+=128;
//	window_ptr+=128;

    /* The trailing edge of the window goes into the delay line */
    delay_ptr = delay;

	{
		__m128 xmm0,xmm1;
		for (int edi=0,esi=0;esi<512;esi+=16,edi-=16){
		    movlps ((uint8_t*)(buf+64)+ esi, xmm0);		 // ? ? ? A
		    movlps (8+(uint8_t*)(buf+64)+ esi, xmm1);		 // ? ? ? C
		    movhps (-16+(uint8_t*)(buf+64)+ edi, xmm1);		 // D ? ? C
		    movhps (-8+(uint8_t*)(buf+64)+ edi, xmm0);		 // B ? ? A
		    xmm0=_mm_shuffle_ps(xmm0,xmm1,0xcc);//shufps $0xCC, xmm1, xmm0		 // D C B A
		    mulps (1024+(uint8_t*)sseWindow+esi, xmm0);
		    movaps (xmm0, (uint8_t*)delay_ptr+ esi);
		}
	}
	delay_ptr+=128;
//	window_ptr-=128;

	{
		__m128 xmm0,xmm1;
		for (int edi=1024,esi=0;esi<512;esi+=16,edi-=16){
		    movlps ((uint8_t*)buf+ esi, xmm0);		 // ? ? A ?
		    movlps (8+(uint8_t*)buf+ esi, xmm1);		 // ? ? C ?
		    movhps (-16+(uint8_t*)buf+ edi, xmm1);		 // ? D C ?
		    movhps (-8+(uint8_t*)buf+ edi, xmm0);		 // ? B A ?
		    xmm0=_mm_shuffle_ps(xmm0,xmm1,0x99);// shufps $0x99, xmm1, xmm0		 // D C B A
		    mulps (1536+(uint8_t*)sseWindow+esi, xmm0);
		    movaps (xmm0, (uint8_t*)delay_ptr+ esi);
		}
	}
}

static void a52_imdct_256_C(sample_t * data, sample_t * delay, sample_t bias)
{
    int i, k;
    sample_t t_r, t_i, a_r, a_i, b_r, b_i, c_r, c_i, d_r, d_i, w_1, w_2;
    const sample_t * window = a52_imdct_window;
    complex_t buf1[64], buf2[64];

    /* Pre IFFT complex multiply plus IFFT cmplx conjugate */
    for (i = 0; i < 64; i++) {
	k = fftorder[i];
	t_r = pre2[i].real;
	t_i = pre2[i].imag;

	buf1[i].real = t_i * data[254-k] + t_r * data[k];
	buf1[i].imag = t_r * data[254-k] - t_i * data[k];

	buf2[i].real = t_i * data[255-k] + t_r * data[k+1];
	buf2[i].imag = t_r * data[255-k] - t_i * data[k+1];
    }

    ifft64 (buf1);
    ifft64 (buf2);

    /* Post IFFT complex multiply */
    /* Window and convert to real valued signal */
    for (i = 0; i < 32; i++) {
	/* y1[n] = z1[n] * (xcos2[n] + j * xs in2[n]) ; */
	t_r = post2[i].real;
	t_i = post2[i].imag;

	a_r = t_r * buf1[i].real    + t_i * buf1[i].imag;
	a_i = t_i * buf1[i].real    - t_r * buf1[i].imag;
	b_r = t_i * buf1[63-i].real + t_r * buf1[63-i].imag;
	b_i = t_r * buf1[63-i].real - t_i * buf1[63-i].imag;

	c_r = t_r * buf2[i].real    + t_i * buf2[i].imag;
	c_i = t_i * buf2[i].real    - t_r * buf2[i].imag;
	d_r = t_i * buf2[63-i].real + t_r * buf2[63-i].imag;
	d_i = t_r * buf2[63-i].real - t_i * buf2[63-i].imag;

	w_1 = window[2*i];
	w_2 = window[255-2*i];
	data[2*i]     = delay[2*i] * w_2 - a_r * w_1 + bias;
	data[255-2*i] = delay[2*i] * w_1 + a_r * w_2 + bias;
	delay[2*i] = c_i;

	w_1 = window[128+2*i];
	w_2 = window[127-2*i];
	data[128+2*i] = delay[127-2*i] * w_2 + a_i * w_1 + bias;
	data[127-2*i] = delay[127-2*i] * w_1 - a_i * w_2 + bias;
	delay[127-2*i] = c_r;

	w_1 = window[2*i+1];
	w_2 = window[254-2*i];
	data[2*i+1]   = delay[2*i+1] * w_2 - b_i * w_1 + bias;
	data[254-2*i] = delay[2*i+1] * w_1 + b_i * w_2 + bias;
	delay[2*i+1] = d_r;

	w_1 = window[129+2*i];
	w_2 = window[126-2*i];
	data[129+2*i] = delay[126-2*i] * w_2 + b_r * w_1 + bias;
	data[126-2*i] = delay[126-2*i] * w_1 - b_r * w_2 + bias;
	delay[126-2*i] = d_i;
    }
}

static double besselI0 (double x)
{
    double bessel = 1;
    int i = 100;

    do
	bessel = bessel * x / (i * i) + 1;
    while (--i);
    return bessel;
}

void a52_imdct_init (uint32_t mm_accel)
{
    int i, k;
    double sum;
    sample_t local_imdct_window[256];

    /* compute imdct window - kaiser-bessel derived window, alpha = 5.0 */
    sum = 0;
    for (i = 0; i < 256; i++) {
	sum += besselI0 (i * (256 - i) * (5 * M_PI / 256) * (5 * M_PI / 256));
	local_imdct_window[i] = sum;
    }
    sum++;

    for (i = 0; i < 256; i++)
	a52_imdct_window[i] = (sample_t) (sqrt (local_imdct_window[i] / sum));

    for (i = 0; i < 3; i++)
	roots16[i] = cos ((M_PI / 8) * (i + 1));

    for (i = 0; i < 7; i++)
	roots32[i] = cos ((M_PI / 16) * (i + 1));

    for (i = 0; i < 15; i++)
	roots64[i] = cos ((M_PI / 32) * (i + 1));

    for (i = 0; i < 31; i++)
	roots128[i] = cos ((M_PI / 64) * (i + 1));

    for (i = 0; i < 64; i++) {
	k = fftorder[i] / 2 + 64;
	pre1[i].real = cos ((M_PI / 256) * (k - 0.25));
	pre1[i].imag = sin ((M_PI / 256) * (k - 0.25));
    }

    for (i = 64; i < 128; i++) {
	k = fftorder[i] / 2 + 64;
	pre1[i].real = -cos ((M_PI / 256) * (k - 0.25));
	pre1[i].imag = -sin ((M_PI / 256) * (k - 0.25));
    }

    for (i = 0; i < 64; i++) {
	post1[i].real = cos ((M_PI / 256) * (i + 0.5));
	post1[i].imag = sin ((M_PI / 256) * (i + 0.5));
    }

    for (i = 0; i < 64; i++) {
	k = fftorder[i] / 4;
	pre2[i].real = cos ((M_PI / 128) * (k - 0.25));
	pre2[i].imag = sin ((M_PI / 128) * (k - 0.25));
    }

    for (i = 0; i < 32; i++) {
	post2[i].real = cos ((M_PI / 128) * (i + 0.5));
	post2[i].imag = sin ((M_PI / 128) * (i + 0.5));
    }

    {
	int i, j, k;

/* Twiddle factors to turn IFFT into IMDCT */
	for (i = 0; i < 128; i++) {
	    xcos1[i] = -cos ((M_PI / 2048) * (8 * i + 1));
	    xsin1[i] = -sin ((M_PI / 2048) * (8 * i + 1));
	}
	for (i = 0; i < 128; i++) {
	    sseSinCos1c[2*i+0]= xcos1[i];
	    sseSinCos1c[2*i+1]= -xcos1[i];
	    sseSinCos1d[2*i+0]= xsin1[i];
	    sseSinCos1d[2*i+1]= xsin1[i];
	}

	/* More twiddle factors to turn IFFT into IMDCT */
	for (i = 0; i < 64; i++) {
	    xcos2[i] = -cos ((M_PI / 1024) * (8 * i + 1));
	    xsin2[i] = -sin ((M_PI / 1024) * (8 * i + 1));
	}

	for (i = 0; i < 7; i++) {
	    j = 1 << i;
	    for (k = 0; k < j; k++) {
		w[i][k].real = cos (-M_PI * k / j);
		w[i][k].imag = sin (-M_PI * k / j);
	    }
	}
	for (i = 1; i < 7; i++) {
	    j = 1 << i;
	    for (k = 0; k < j; k+=2) {

	    	sseW[i][4*k + 0] = w[i][k+0].real;
	    	sseW[i][4*k + 1] = w[i][k+0].real;
	    	sseW[i][4*k + 2] = w[i][k+1].real;
	    	sseW[i][4*k + 3] = w[i][k+1].real;

	    	sseW[i][4*k + 4] = -w[i][k+0].imag;
	    	sseW[i][4*k + 5] = w[i][k+0].imag;
	    	sseW[i][4*k + 6] = -w[i][k+1].imag;
	    	sseW[i][4*k + 7] = w[i][k+1].imag;

	//we multiply more or less uninitialized numbers so we need to use exactly 0.0
		if(k==0)
		{
//			sseW[i][4*k + 0]= sseW[i][4*k + 1]= 1.0;
			sseW[i][4*k + 4]= sseW[i][4*k + 5]= 0.0;
		}

		if(2*k == j)
		{
			sseW[i][4*k + 0]= sseW[i][4*k + 1]= 0.0;
//			sseW[i][4*k + 4]= -(sseW[i][4*k + 5]= -1.0);
		}
	    }
	}

	for(i=0; i<128; i++)
	{
		sseWindow[2*i+0]= -imdct_window[2*i+0];
		sseWindow[2*i+1]=  imdct_window[2*i+1];
	}

	for(i=0; i<64; i++)
	{
		sseWindow[256 + 2*i+0]= -imdct_window[254 - 2*i+1];
		sseWindow[256 + 2*i+1]=  imdct_window[254 - 2*i+0];
		sseWindow[384 + 2*i+0]=  imdct_window[126 - 2*i+1];
		sseWindow[384 + 2*i+1]= -imdct_window[126 - 2*i+0];
	}
    }


    {
	//fprintf (stderr, "No accelerated IMDCT transform found\n");
	ifft128 = ifft128_c;
	ifft64 = ifft64_c;
    }
#ifndef __GNUC__
    if(mm_accel & FF_CPU_SSE)
        a52_imdct_512 = imdct_do_512_sse;
    else
#endif
    a52_imdct_512 = a52_imdct_512_C;
    a52_imdct_256 = a52_imdct_256_C;
}