Improvements from Matjaz Thaler

1 files changed, 398 insertions, 336 deletions

diff --git a/ac3dec/imdct.c b/ac3dec/imdct.c
index ae2794ed..c09ef413 100644
--- a/ac3dec/imdct.c
+++ b/ac3dec/imdct.c
@@ -28,75 +28,48 @@
 #include "ac3.h"
 #include "ac3_internal.h"
 
-
-#include "decode.h"
+#include "downmix.h"
 #include "imdct.h"
+#include "imdct_c.h"
+#ifdef HAVE_KNI
+#include "imdct_kni.h"
+#endif
+#include "srfft.h"
 
-void imdct_do_256(float data[],float delay[]);
-void imdct_do_512(float data[],float delay[]);
 
-typedef struct complex_s
-{
-	float real;
-	float imag;
-} complex_t;
+extern void (*downmix_3f_2r_to_2ch)(float *samples, dm_par_t * dm_par);
+extern void (*downmix_3f_1r_to_2ch)(float *samples, dm_par_t * dm_par);
+extern void (*downmix_2f_2r_to_2ch)(float *samples, dm_par_t * dm_par);
+extern void (*downmix_2f_1r_to_2ch)(float *samples, dm_par_t * dm_par);
+extern void (*downmix_3f_0r_to_2ch)(float *samples, dm_par_t * dm_par);
+
 
+extern void (*stream_sample_2ch_to_s16)(int16_t *s16_samples, float *left, float *right);
+extern void (*stream_sample_1ch_to_s16)(int16_t *s16_samples, float *center);
+
+void (*fft_64p) (complex_t *);
+void (*imdct_do_512) (float data[],float delay[]);
+void (*imdct_do_512_nol) (float data[], float delay[]);
+
+void imdct_do_256 (float data[],float delay[]);
 
 #define N 512
 
+/* static complex_t buf[128]; */
+//static complex_t buf[128] __attribute__((aligned(16)));
+complex_t buf[128] __attribute__((aligned(16)));
 
-/* 128 point bit-reverse LUT */
-static uint_8 bit_reverse_512[128] = {
-	0x00, 0x40, 0x20, 0x60, 0x10, 0x50, 0x30, 0x70, 
-	0x08, 0x48, 0x28, 0x68, 0x18, 0x58, 0x38, 0x78, 
-	0x04, 0x44, 0x24, 0x64, 0x14, 0x54, 0x34, 0x74, 
-	0x0c, 0x4c, 0x2c, 0x6c, 0x1c, 0x5c, 0x3c, 0x7c, 
-	0x02, 0x42, 0x22, 0x62, 0x12, 0x52, 0x32, 0x72, 
-	0x0a, 0x4a, 0x2a, 0x6a, 0x1a, 0x5a, 0x3a, 0x7a, 
-	0x06, 0x46, 0x26, 0x66, 0x16, 0x56, 0x36, 0x76, 
-	0x0e, 0x4e, 0x2e, 0x6e, 0x1e, 0x5e, 0x3e, 0x7e, 
-	0x01, 0x41, 0x21, 0x61, 0x11, 0x51, 0x31, 0x71, 
-	0x09, 0x49, 0x29, 0x69, 0x19, 0x59, 0x39, 0x79, 
-	0x05, 0x45, 0x25, 0x65, 0x15, 0x55, 0x35, 0x75, 
-	0x0d, 0x4d, 0x2d, 0x6d, 0x1d, 0x5d, 0x3d, 0x7d, 
-	0x03, 0x43, 0x23, 0x63, 0x13, 0x53, 0x33, 0x73, 
-	0x0b, 0x4b, 0x2b, 0x6b, 0x1b, 0x5b, 0x3b, 0x7b, 
-	0x07, 0x47, 0x27, 0x67, 0x17, 0x57, 0x37, 0x77, 
-	0x0f, 0x4f, 0x2f, 0x6f, 0x1f, 0x5f, 0x3f, 0x7f};
-
-static uint_8 bit_reverse_256[64] = {
-	0x00, 0x20, 0x10, 0x30, 0x08, 0x28, 0x18, 0x38, 
-	0x04, 0x24, 0x14, 0x34, 0x0c, 0x2c, 0x1c, 0x3c, 
-	0x02, 0x22, 0x12, 0x32, 0x0a, 0x2a, 0x1a, 0x3a, 
-	0x06, 0x26, 0x16, 0x36, 0x0e, 0x2e, 0x1e, 0x3e, 
-	0x01, 0x21, 0x11, 0x31, 0x09, 0x29, 0x19, 0x39, 
-	0x05, 0x25, 0x15, 0x35, 0x0d, 0x2d, 0x1d, 0x3d, 
-	0x03, 0x23, 0x13, 0x33, 0x0b, 0x2b, 0x1b, 0x3b, 
-	0x07, 0x27, 0x17, 0x37, 0x0f, 0x2f, 0x1f, 0x3f};
-
-static complex_t buf[128];
-
-/* Twiddle factor LUT */
-static complex_t *w[7];
-static complex_t w_1[1];
-static complex_t w_2[2];
-static complex_t w_4[4];
-static complex_t w_8[8];
-static complex_t w_16[16];
-static complex_t w_32[32];
-static complex_t w_64[64];
+/* Delay buffer for time domain interleaving */
+static float delay[6][256];
+static float delay1[6][256];
 
 /* Twiddle factors for IMDCT */
-static float xcos1[128];
-static float xsin1[128];
 static float xcos2[64];
 static float xsin2[64];
 
-/* Delay buffer for time domain interleaving */
-static float delay[6][256];
-
 /* Windowing function for Modified DCT - Thank you acroread */
-static float window[] = {
+//static float window[] = {
+float window[] = {
 	0.00014, 0.00024, 0.00037, 0.00051, 0.00067, 0.00086, 0.00107, 0.00130,
 	0.00157, 0.00187, 0.00220, 0.00256, 0.00297, 0.00341, 0.00390, 0.00443,
 	0.00501, 0.00564, 0.00632, 0.00706, 0.00785, 0.00871, 0.00962, 0.01061,
@@ -128,146 +101,116 @@ static float window[] = {
 	0.99978, 0.99981, 0.99984, 0.99986, 0.99988, 0.99990, 0.99992, 0.99993,
 	0.99994, 0.99995, 0.99996, 0.99997, 0.99998, 0.99998, 0.99998, 0.99999,
 	0.99999, 0.99999, 0.99999, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000,
-	1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000 };
-
+	1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000, 1.00000
+};
 
-static inline void swap_cmplx(complex_t *a, complex_t *b)
+//static const int pm128[128] =
+const int pm128[128] =
 {
-	complex_t tmp;
-
-	tmp = *a;
-	*a = *b;
-	*b = tmp;
-}
-
-
-
-static inline complex_t cmplx_mult(complex_t a, complex_t b)
+	0, 16, 32, 48, 64, 80,  96, 112,  8, 40, 72, 104, 24, 56,  88, 120,
+	4, 20, 36, 52, 68, 84, 100, 116, 12, 28, 44,  60, 76, 92, 108, 124,
+	2, 18, 34, 50, 66, 82,  98, 114, 10, 42, 74, 106, 26, 58,  90, 122,
+	6, 22, 38, 54, 70, 86, 102, 118, 14, 46, 78, 110, 30, 62,  94, 126,
+	1, 17, 33, 49, 65, 81,  97, 113,  9, 41, 73, 105, 25, 57,  89, 121,
+	5, 21, 37, 53, 69, 85, 101, 117, 13, 29, 45,  61, 77, 93, 109, 125,
+	3, 19, 35, 51, 67, 83,  99, 115, 11, 43, 75, 107, 27, 59,  91, 123,
+	7, 23, 39, 55, 71, 87, 103, 119, 15, 31, 47,  63, 79, 95, 111, 127
+}; 
+
+static const int pm64[64] =
 {
-	complex_t ret;
-
-	ret.real = a.real * b.real - a.imag * b.imag;
-	ret.imag = a.real * b.imag + a.imag * b.real;
-
-	return ret;
-}
-
-void imdct_init(void)
-{
-	int i,k;
-	complex_t angle_step;
-	complex_t current_angle;
-
-	/* Twiddle factors to turn IFFT into IMDCT */
-	for( i=0; i < 128; i++)
-	{
-		xcos1[i] = -cos(2.0f * M_PI * (8*i+1)/(8*N)) ; 
-		xsin1[i] = -sin(2.0f * M_PI * (8*i+1)/(8*N)) ;
-	}
-	
-	/* More twiddle factors to turn IFFT into IMDCT */
-	for( i=0; i < 64; i++)
-	{
-		xcos2[i] = -cos(2.0f * M_PI * (8*i+1)/(4*N)) ; 
-		xsin2[i] = -sin(2.0f * M_PI * (8*i+1)/(4*N)) ;
-	}
-
-	/* Canonical twiddle factors for FFT */
-	w[0] = w_1;
-	w[1] = w_2;
-	w[2] = w_4;
-	w[3] = w_8;
-	w[4] = w_16;
-	w[5] = w_32;
-	w[6] = w_64;
-
-	for( i = 0; i < 7; i++)
-	{
-		angle_step.real = cos(-2.0 * M_PI / (1 << (i+1)));
-		angle_step.imag = sin(-2.0 * M_PI / (1 << (i+1)));
-
-		current_angle.real = 1.0;
-		current_angle.imag = 0.0;
-
-		for (k = 0; k < 1 << i; k++)
-		{
-			w[i][k] = current_angle;
-			current_angle = cmplx_mult(current_angle,angle_step);
-		}
+	0,  8, 16, 24, 32, 40, 48, 56,
+	4, 20, 36, 52, 12, 28, 44, 60,
+	2, 10, 18, 26, 34, 42, 50, 58,
+	6, 14, 22, 30, 38, 46, 54, 62,
+	1,  9, 17, 25, 33, 41, 49, 57,
+	5, 21, 37, 53, 13, 29, 45, 61,
+	3, 11, 19, 27, 35, 43, 51, 59,
+	7, 23, 39, 55, 15, 31, 47, 63
+};
+
+
+void imdct_init (void)
+ {
+	int i;
+	float scale = 255.99609372;
+
+#ifdef __i386__
+#ifdef HAVE_KNI
+	if (!imdct_init_kni ());
+	else
+#endif
+#endif
+	if (!imdct_init_c ());
+
+	// More twiddle factors to turn IFFT into IMDCT */
+	for (i=0; i < 64; i++) {
+		xcos2[i] = cos(2.0f * M_PI * (8*i+1)/(4*N)) * scale;
+		xsin2[i] = sin(2.0f * M_PI * (8*i+1)/(4*N)) * scale;
 	}
 }
 
-void
-imdct_do_512(float data[],float delay[])
+
+void imdct_do_256 (float data[],float delay[])
 {
-	int i,k;
-	int p,q;
-	int m;
-	int two_m;
-	int two_m_plus_one;
+	int i, j, k;
+	int p, q;
 
 	float tmp_a_i;
 	float tmp_a_r;
-	float tmp_b_i;
-	float tmp_b_r;
 
 	float *data_ptr;
 	float *delay_ptr;
 	float *window_ptr;
-	
-	//
-	// 512 IMDCT with source and dest data in 'data'
-	//
-	
-	// Pre IFFT complex multiply plus IFFT cmplx conjugate and bit reverse
-	// permutation
-	for( i=0; i < 128; i++)
-	{
-		k = bit_reverse_512[i];
-
-		/* z[i] = (X[256-2*i-1] + j * X[2*i]) * (xcos1[i] + j * xsin1[i]) ; */ 
-		buf[k].real =         (data[256-2*i-1] * xcos1[i])  -  (data[2*i]       * xsin1[i]);
-	  buf[k].imag = -1.0 * ((data[2*i]       * xcos1[i])  +  (data[256-2*i-1] * xsin1[i]));
-	}
 
-	// FFT Merge 
-	for (m=0; m < 7; m++)
-	{
-		if(m)
-			two_m = (1 << m);
-		else
-			two_m = 1;
-
-		two_m_plus_one = (1 << (m+1));
-
-		for(k = 0; k < two_m; k++)
-		{
-			for(i = 0; i < 128; i += two_m_plus_one)
-			{
-				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;
+	complex_t *buf1, *buf2;
 
-			}
-		}
+	buf1 = &buf[0];
+	buf2 = &buf[64];
+
+// Pre IFFT complex multiply plus IFFT complex conjugate
+	for (k=0; k<64; k++) { 
+		/* X1[k] = X[2*k]	*/
+		/* X2[k] = X[2*k+1]	*/
+
+		j = pm64[k];
+		p = 2 * (128-2*j-1);
+		q = 2 * (2 * j);
+
+		/* Z1[k] = (X1[128-2*k-1] + j * X1[2*k]) * (xcos2[k] + j * xsin2[k]); */
+		buf1[k].re =         data[p] * xcos2[j] - data[q] * xsin2[j];
+		buf1[k].im = -1.0f * (data[q] * xcos2[j] + data[p] * xsin2[j]);
+		/* Z2[k] = (X2[128-2*k-1] + j * X2[2*k]) * (xcos2[k] + j * xsin2[k]); */
+		buf2[k].re =          data[p + 1] * xcos2[j] - data[q + 1] * xsin2[j];
+		buf2[k].im = -1.0f * ( data[q + 1] * xcos2[j] + data[p + 1] * xsin2[j]);
 	}
 
-	/* Post IFFT complex multiply  plus IFFT complex conjugate*/
-	for( i=0; i < 128; i++)
-	{
-		/* y[n] = z[n] * (xcos1[n] + j * xsin1[n]) ; */
-		tmp_a_r = buf[i].real;
-		tmp_a_i = buf[i].imag;
-		//Note that I flipped the signs on the imaginary ops to do the complex conj
-		buf[i].real =(tmp_a_r * xcos1[i])  +  (tmp_a_i  * xsin1[i]);
-	  buf[i].imag =(tmp_a_r * xsin1[i])  -  (tmp_a_i  * xcos1[i]);
+	fft_64p(&buf1[0]);
+	fft_64p(&buf2[0]);
+
+#ifdef DEBUG
+       //DEBUG FFT
+#if 0
+	printf ("Post FFT, buf1\n");
+	for (i=0; i < 64; i++)
+		printf("%d %f %f\n", i, buf_1[i].re, buf_1[i].im);
+	printf ("Post FFT, buf2\n");
+	for (i=0; i < 64; i++)
+		printf("%d %f %f\n", i, buf_2[i].re, buf_2[i].im);
+#endif
+#endif
+
+
+	// Post IFFT complex multiply 
+	for( i=0; i < 64; i++) {
+		tmp_a_r =  buf1[i].re;
+		tmp_a_i = -buf1[i].im;
+		buf1[i].re =(tmp_a_r * xcos2[i])  -  (tmp_a_i  * xsin2[i]);
+		buf1[i].im =(tmp_a_r * xsin2[i])  +  (tmp_a_i  * xcos2[i]);
+		tmp_a_r =  buf2[i].re;
+		tmp_a_i = -buf2[i].im;
+		buf2[i].re =(tmp_a_r * xcos2[i])  -  (tmp_a_i  * xsin2[i]);
+		buf2[i].im =(tmp_a_r * xsin2[i])  +  (tmp_a_i  * xcos2[i]);
 	}
 	
 	data_ptr = data;
@@ -275,164 +218,122 @@ imdct_do_512(float data[],float delay[])
 	window_ptr = window;
 
 	/* Window and convert to real valued signal */
-	for(i=0; i< 64; i++) 
-	{ 
-		*data_ptr++   = 2.0f * (-buf[64+i].imag   * *window_ptr++ + *delay_ptr++); 
-		*data_ptr++   = 2.0f * ( buf[64-i-1].real * *window_ptr++ + *delay_ptr++); 
+	for(i=0; i< 64; i++) { 
+		*data_ptr++  = -buf1[i].im      * *window_ptr++ + *delay_ptr++;
+		*data_ptr++  = buf1[64-i-1].re * *window_ptr++ + *delay_ptr++;
 	}
 
-	for(i=0; i< 64; i++) 
-	{ 
-		*data_ptr++  = 2.0f * (-buf[i].real       * *window_ptr++ + *delay_ptr++); 
-		*data_ptr++  = 2.0f * ( buf[128-i-1].imag * *window_ptr++ + *delay_ptr++); 
+	for(i=0; i< 64; i++) {
+		*data_ptr++  = -buf1[i].re      * *window_ptr++ + *delay_ptr++;
+		*data_ptr++  = buf1[64-i-1].im * *window_ptr++ + *delay_ptr++;
 	}
 	
-	/* The trailing edge of the window goes into the delay line */
 	delay_ptr = delay;
 
-	for(i=0; i< 64; i++) 
-	{ 
-		*delay_ptr++  = -buf[64+i].real   * *--window_ptr; 
-		*delay_ptr++  =  buf[64-i-1].imag * *--window_ptr; 
+	for(i=0; i< 64; i++) {
+		*delay_ptr++ = -buf2[i].re      * *--window_ptr;
+		*delay_ptr++ =  buf2[64-i-1].im * *--window_ptr;
 	}
 
-	for(i=0; i<64; i++) 
-	{
-		*delay_ptr++  =  buf[i].imag       * *--window_ptr; 
-		*delay_ptr++  = -buf[128-i-1].real * *--window_ptr; 
+	for(i=0; i< 64; i++) {
+		*delay_ptr++ =  buf2[i].im      * *--window_ptr;
+		*delay_ptr++ = -buf2[64-i-1].re * *--window_ptr;
 	}
 }
 
-void
-imdct_do_256(float data[],float delay[])
+
+/**
+ *
+ **/
+
+void imdct_do_256_nol (float data[], float delay[])
 {
-	int i,k;
-	int p,q;
-	int m;
-	int two_m;
-	int two_m_plus_one;
+	int i, j, k;
+	int p, q;
 
 	float tmp_a_i;
 	float tmp_a_r;
-	float tmp_b_i;
-	float tmp_b_r;
 
 	float *data_ptr;
 	float *delay_ptr;
 	float *window_ptr;
 
-	complex_t *buf_1, *buf_2;
-
-	buf_1 = &buf[0];
-	buf_2 = &buf[64];
-
-	// Pre IFFT complex multiply plus IFFT cmplx conjugate and bit reverse
-	// permutation
-	for(i=0; i<64; i++) 
-	{ 
-		/* X1[i] = X[2*i]  */
-		/* X2[i] = X[2*i+1]     */
-
-		k = bit_reverse_256[i];
-
-		p = 2 * (128-2*i-1);
-		q = 2 * (2 * i);
-
-		/* Z1[i] = (X1[128-2*i-1] + j * X1[2*i]) * (xcos2[i] + j * xsin2[i]); */ 
-		buf_1[k].real =         data[p] * xcos2[i] - data[q] * xsin2[i];
-	  buf_1[k].imag = -1.0f * (data[q] * xcos2[i] + data[p] * xsin2[i]); 
-		/* Z2[i] = (X2[128-2*i-1] + j * X2[2*i]) * (xcos2[i] + j * xsin2[i]); */ 
-		buf_2[k].real =          data[p + 1] * xcos2[i] - data[q + 1] * xsin2[i];
-	  buf_2[k].imag = -1.0f * ( data[q + 1] * xcos2[i] + data[p + 1] * xsin2[i]); 
-	}
-
-	// FFT Merge 
-	for (m=0; m < 6; m++)
-	{
-		two_m = (1 << m);
-		two_m_plus_one = (1 << (m+1));
-
-		if(m)
-			two_m = (1 << m);
-		else
-			two_m = 1;
-
-		for(k = 0; k < two_m; k++)
-		{
-			for(i = 0; i < 64; i += two_m_plus_one)
-			{
-				p = k + i;
-				q = p + two_m;
-				//Do block 1
-				tmp_a_r = buf_1[p].real;
-				tmp_a_i = buf_1[p].imag;
-				tmp_b_r = buf_1[q].real * w[m][k].real - buf_1[q].imag * w[m][k].imag;
-				tmp_b_i = buf_1[q].imag * w[m][k].real + buf_1[q].real * w[m][k].imag;
-				buf_1[p].real = tmp_a_r + tmp_b_r;
-				buf_1[p].imag =  tmp_a_i + tmp_b_i;
-				buf_1[q].real = tmp_a_r - tmp_b_r;
-				buf_1[q].imag =  tmp_a_i - tmp_b_i;
-
-				//Do block 2
-				tmp_a_r = buf_2[p].real;
-				tmp_a_i = buf_2[p].imag;
-				tmp_b_r = buf_2[q].real * w[m][k].real - buf_2[q].imag * w[m][k].imag;
-				tmp_b_i = buf_2[q].imag * w[m][k].real + buf_2[q].real * w[m][k].imag;
-				buf_2[p].real = tmp_a_r + tmp_b_r;
-				buf_2[p].imag =  tmp_a_i + tmp_b_i;
-				buf_2[q].real = tmp_a_r - tmp_b_r;
-				buf_2[q].imag =  tmp_a_i - tmp_b_i;
-
-			}
-		}
-	}
-
-	// Post IFFT complex multiply 
-	for( i=0; i < 64; i++)
-	{
-		//Note that I flipped the signs on the imaginary ops to do the complex conj
-		
-		/* y1[n] = z1[n] * (xcos2[n] + j * xs in2[n]) ; */ 
-		tmp_a_r = buf_1[i].real;
-		tmp_a_i = buf_1[i].imag;
-		buf_1[i].real =(tmp_a_r * xcos2[i])  +  (tmp_a_i  * xsin2[i]);
-	  buf_1[i].imag =(tmp_a_r * xsin2[i])  -  (tmp_a_i  * xcos2[i]);
-		/* y2[n] = z2[n] * (xcos2[n] + j * xsin2[n]) ; */ 
-		tmp_a_r = buf_2[i].real;
-		tmp_a_i = buf_2[i].imag;
-		buf_2[i].real =(tmp_a_r * xcos2[i])  +  (tmp_a_i  * xsin2[i]);
-	  buf_2[i].imag =(tmp_a_r * xsin2[i])  -  (tmp_a_i  * xcos2[i]);
-	}
-	
-	data_ptr = data;
-	delay_ptr = delay;
-	window_ptr = window;
-
-	/* Window and convert to real valued signal */
-	for(i=0; i< 64; i++) 
-	{ 
-		*data_ptr++  = 2.0f * (-buf_1[i].imag      * *window_ptr++ + *delay_ptr++);
-		*data_ptr++  = 2.0f * ( buf_1[64-i-1].real * *window_ptr++ + *delay_ptr++);
-	}
-
-	for(i=0; i< 64; i++) 
-	{
-		*data_ptr++  = 2.0f * (-buf_1[i].real      * *window_ptr++ + *delay_ptr++);
-		*data_ptr++  = 2.0f * ( buf_1[64-i-1].imag * *window_ptr++ + *delay_ptr++);
-	}
-	
-	delay_ptr = delay;
-
-	for(i=0; i< 64; i++) 
-	{
-		*delay_ptr++ = -buf_2[i].real      * *--window_ptr;
-		*delay_ptr++ =  buf_2[64-i-1].imag * *--window_ptr;
-	}
-
-	for(i=0; i< 64; i++) 
-	{
-		*delay_ptr++ =  buf_2[i].imag      * *--window_ptr;
-		*delay_ptr++ = -buf_2[64-i-1].real * *--window_ptr;
+	complex_t *buf1, *buf2;
+
+	buf1 = &buf[0];
+	buf2 = &buf[64];
+
+       /* Pre IFFT complex multiply plus IFFT cmplx conjugate */
+	for(k=0; k<64; k++) {
+               /* X1[k] = X[2*k]  */
+               /* X2[k] = X[2*k+1]     */
+               j = pm64[k];
+               p = 2 * (128-2*j-1);
+               q = 2 * (2 * j);
+
+               /* Z1[k] = (X1[128-2*k-1] + j * X1[2*k]) * (xcos2[k] + j * xsin2[k]); */
+               buf1[k].re =         data[p] * xcos2[j] - data[q] * xsin2[j];
+               buf1[k].im = -1.0f * (data[q] * xcos2[j] + data[p] * xsin2[j]);
+               /* Z2[k] = (X2[128-2*k-1] + j * X2[2*k]) * (xcos2[k] + j * xsin2[k]); */
+               buf2[k].re =          data[p + 1] * xcos2[j] - data[q + 1] * xsin2[j];
+               buf2[k].im = -1.0f * ( data[q + 1] * xcos2[j] + data[p + 1] * xsin2[j]);
+       }
+
+
+       fft_64p(&buf1[0]);
+       fft_64p(&buf2[0]);
+
+#ifdef DEBUG
+	//DEBUG FFT
+#if 0
+       printf("Post FFT, buf1\n");
+       for (i=0; i < 64; i++)
+               printf("%d %f %f\n", i, buf_1[i].re, buf_1[i].im);
+       printf("Post FFT, buf2\n");
+       for (i=0; i < 64; i++)
+               printf("%d %f %f\n", i, buf_2[i].re, buf_2[i].im);
+#endif
+#endif
+
+       /* Post IFFT complex multiply */
+       for( i=0; i < 64; i++) {
+               /* y1[n] = z1[n] * (xcos2[n] + j * xs in2[n]) ; */
+               tmp_a_r =  buf1[i].re;
+               tmp_a_i = -buf1[i].im;
+               buf1[i].re =(tmp_a_r * xcos2[i])  -  (tmp_a_i  * xsin2[i]);
+               buf1[i].im =(tmp_a_r * xsin2[i])  +  (tmp_a_i  * xcos2[i]);
+               /* y2[n] = z2[n] * (xcos2[n] + j * xsin2[n]) ; */
+               tmp_a_r =  buf2[i].re;
+               tmp_a_i = -buf2[i].im;
+               buf2[i].re =(tmp_a_r * xcos2[i])  -  (tmp_a_i  * xsin2[i]);
+               buf2[i].im =(tmp_a_r * xsin2[i])  +  (tmp_a_i  * xcos2[i]);
+       }
+      
+       data_ptr = data;
+       delay_ptr = delay;
+       window_ptr = window;
+
+       /* Window and convert to real valued signal, no overlap */
+       for(i=0; i< 64; i++) {
+               *data_ptr++  = -buf1[i].im      * *window_ptr++;
+               *data_ptr++  = buf1[64-i-1].re * *window_ptr++;
+       }
+
+       for(i=0; i< 64; i++) {
+               *data_ptr++  = -buf1[i].re      * *window_ptr++ + *delay_ptr++;
+               *data_ptr++  = buf1[64-i-1].im * *window_ptr++ + *delay_ptr++;
+       }
+
+       delay_ptr = delay;
+
+       for(i=0; i< 64; i++) {
+               *delay_ptr++ = -buf2[i].re      * *--window_ptr;
+               *delay_ptr++ =  buf2[64-i-1].im * *--window_ptr;
+       }
+
+       for(i=0; i< 64; i++) {
+               *delay_ptr++ =  buf2[i].im      * *--window_ptr;
+               *delay_ptr++ = -buf2[64-i-1].re * *--window_ptr;
 	}
 }
 
@@ -440,29 +341,190 @@ imdct_do_256(float data[],float delay[])
 ///#include <sys/time.h>
 //FIXME remove
 
-void 
-imdct(bsi_t *bsi,audblk_t *audblk, stream_samples_t samples) {
+void imdct (bsi_t *bsi,audblk_t *audblk, stream_samples_t samples, int16_t *s16_samples, dm_par_t* dm_par)
+{
 	int i;
+	int doable = 0;
+	float *center=NULL, *left, *right, *left_sur, *right_sur;
+	float *delay_left, *delay_right;
+	float *delay1_left, *delay1_right, *delay1_center, *delay1_sr, *delay1_sl;
+	float right_tmp, left_tmp;
+	void (*do_imdct)(float data[], float deley[]);
+
+	// test if dm in frequency is doable
+	if (!(doable = audblk->blksw[0]))
+		do_imdct = imdct_do_512;
+	else
+		do_imdct = imdct_do_256;
+
+	// downmix in the frequency domain if all the channels
+	// use the same imdct
+	for (i=0; i < bsi->nfchans; i++) {
+		if (doable != audblk->blksw[i]) {
+			do_imdct = NULL;
+			break;
+		}
+	}
 
-	//handy timing code
-	//struct timeval start,end;
+	if (do_imdct) {
+		//dowmix first and imdct
+		switch(bsi->acmod) {
+		case 7:		// 3/2
+			downmix_3f_2r_to_2ch (samples[0], dm_par);
+			break;
+		case 6:		// 2/2
+			downmix_2f_2r_to_2ch (samples[0], dm_par);
+			break;
+		case 5:		// 3/1
+			downmix_3f_1r_to_2ch (samples[0], dm_par);
+			break;
+		case 4:		// 2/1
+			downmix_2f_1r_to_2ch (samples[0], dm_par);
+			break;
+		case 3:		// 3/0
+			downmix_3f_0r_to_2ch (samples[0], dm_par);
+			break;
+		case 2:
+			break;
+		default:	// 1/0
+			if (bsi->acmod == 1)
+				center = samples[0];
+			else if (bsi->acmod == 0)
+				center = samples[ac3_config.dual_mono_ch_sel];
+			do_imdct(center, delay[0]); // no downmix
+
+			stream_sample_1ch_to_s16 (s16_samples, center);
+
+			return;
+			//goto done;
+			break;
+		}
 
-	//gettimeofday(&start,0);
-	
-	for(i=0; i<bsi->nfchans;i++)
-	{
-		if(audblk->blksw[i])
-			imdct_do_256(samples[i],delay[i]);
-		else
-			imdct_do_512(samples[i],delay[i]);
+		do_imdct (samples[0], delay[0]);
+		do_imdct (samples[1], delay[1]);
+		stream_sample_2ch_to_s16(s16_samples, samples[0], samples[1]);
+
+	} else {		//imdct and then dowmix
+		// delay and samples should be saved and mixed
+		//fprintf(stderr, "time domain downmix\n");
+		for (i=0; i<bsi->nfchans; i++) {
+			if (audblk->blksw[i])
+				imdct_do_256_nol (samples[i],delay1[i]);
+			else
+				imdct_do_512_nol (samples[i],delay1[i]);
+		}
+
+		// mix the sample, overlap
+		switch(bsi->acmod) {
+		case 7:		// 3/2
+			left = samples[0];
+			center = samples[1];
+			right = samples[2];
+			left_sur = samples[3];
+			right_sur = samples[4];
+			delay_left = delay[0];
+			delay_right = delay[1];
+			delay1_left = delay1[0];
+			delay1_center = delay1[1];
+			delay1_right = delay1[2];
+			delay1_sl = delay1[3];
+			delay1_sr = delay1[4];
+
+			for (i = 0; i < 256; i++) {
+				left_tmp = dm_par->unit * *left++  + dm_par->clev * *center  + dm_par->slev * *left_sur++;
+				right_tmp= dm_par->unit * *right++ + dm_par->clev * *center++ + dm_par->slev * *right_sur++;
+				*s16_samples++ = (int16_t)(left_tmp + *delay_left);
+				*s16_samples++ = (int16_t)(right_tmp + *delay_right);
+				*delay_left++ = dm_par->unit * *delay1_left++  + dm_par->clev * *delay1_center  + dm_par->slev * *delay1_sl++;
+				*delay_right++ = dm_par->unit * *delay1_right++ + dm_par->clev * *center++ + dm_par->slev * *delay1_sr++;
+			}
+			break;
+		case 6:		// 2/2
+			left = samples[0];
+			right = samples[1];
+			left_sur = samples[2];
+			right_sur = samples[3];
+			delay_left = delay[0];
+			delay_right = delay[1];
+			delay1_left = delay1[0];
+			delay1_right = delay1[1];
+			delay1_sl = delay1[2];
+			delay1_sr = delay1[3];
+
+			for (i = 0; i < 256; i++) {
+				left_tmp = dm_par->unit * *left++  + dm_par->slev * *left_sur++;
+				right_tmp= dm_par->unit * *right++ + dm_par->slev * *right_sur++;
+				*s16_samples++ = (int16_t)(left_tmp + *delay_left);
+				*s16_samples++ = (int16_t)(right_tmp + *delay_right);
+				*delay_left++ = dm_par->unit * *delay1_left++  + dm_par->slev * *delay1_sl++;
+				*delay_right++ = dm_par->unit * *delay1_right++ + dm_par->slev * *delay1_sr++;
+			}
+			break;
+		case 5:		// 3/1
+			left = samples[0];
+			center = samples[1];
+			right = samples[2];
+			right_sur = samples[3];
+			delay_left = delay[0];
+			delay_right = delay[1];
+			delay1_left = delay1[0];
+			delay1_center = delay1[1];
+			delay1_right = delay1[2];
+			delay1_sl = delay1[3];
+
+			for (i = 0; i < 256; i++) {
+				left_tmp = dm_par->unit * *left++  + dm_par->clev * *center  - dm_par->slev * *right_sur;
+				right_tmp= dm_par->unit * *right++ + dm_par->clev * *center++ + dm_par->slev * *right_sur++;
+				*s16_samples++ = (int16_t)(left_tmp + *delay_left);
+				*s16_samples++ = (int16_t)(right_tmp + *delay_right);
+				*delay_left++ = dm_par->unit * *delay1_left++  + dm_par->clev * *delay1_center  + dm_par->slev * *delay1_sl;
+				*delay_right++ = dm_par->unit * *delay1_right++ + dm_par->clev * *center++ + dm_par->slev * *delay1_sl++;
+			}
+			break;
+		case 4:		// 2/1
+			left = samples[0];
+			right = samples[1];
+			right_sur = samples[2];
+			delay_left = delay[0];
+			delay_right = delay[1];
+			delay1_left = delay1[0];
+			delay1_right = delay1[1];
+			delay1_sl = delay1[2];
+
+			for (i = 0; i < 256; i++) {
+				left_tmp = dm_par->unit * *left++ - dm_par->slev * *right_sur;
+				right_tmp= dm_par->unit * *right++ + dm_par->slev * *right_sur++;
+				*s16_samples++ = (int16_t)(left_tmp + *delay_left);
+				*s16_samples++ = (int16_t)(right_tmp + *delay_right);
+				*delay_left++ = dm_par->unit * *delay1_left++ + dm_par->slev * *delay1_sl;
+				*delay_right++ = dm_par->unit * *delay1_right++ + dm_par->slev * *delay1_sl++;
+			}
+			break;
+		case 3:		// 3/0
+			left = samples[0];
+			center = samples[1];
+			right = samples[2];
+			delay_left = delay[0];
+			delay_right = delay[1];
+			delay1_left = delay1[0];
+			delay1_center = delay1[1];
+			delay1_right = delay1[2];
+
+			for (i = 0; i < 256; i++) {
+				left_tmp = dm_par->unit * *left++  + dm_par->clev * *center;
+				right_tmp= dm_par->unit * *right++ + dm_par->clev * *center++;
+				*s16_samples++ = (int16_t)(left_tmp + *delay_left);
+				*s16_samples++ = (int16_t)(right_tmp + *delay_right);
+				*delay_left++ = dm_par->unit * *delay1_left++  + dm_par->clev * *delay1_center;
+				*delay_right++ = dm_par->unit * *delay1_right++ + dm_par->clev * *center++;
+			}
+			break;
+		case 2:		// copy to output
+			for (i = 0; i < 256; i++) {
+				*s16_samples++ = (int16_t)samples[0][i];
+				*s16_samples++ = (int16_t)samples[1][i];
+			}
+			break;
+		}
 	}
-	//gettimeofday(&end,0);
-	//printf("imdct %ld us\n",(end.tv_sec - start.tv_sec) * 1000000 +
-        //end.tv_usec - start.tv_usec);
-
-	//XXX We don't bother with the IMDCT for the LFE as it's currently
-	//unused.
-	//if (bsi->lfeon)
-	//	imdct_do_512(coeffs->lfe,samples->channel[5],delay[5]);
-	//	
 }