diff options
Diffstat (limited to 'mp3lib/dct36.c')
-rw-r--r-- | mp3lib/dct36.c | 269 |
1 files changed, 0 insertions, 269 deletions
diff --git a/mp3lib/dct36.c b/mp3lib/dct36.c deleted file mode 100644 index 22ec273277..0000000000 --- a/mp3lib/dct36.c +++ /dev/null @@ -1,269 +0,0 @@ -/* - * Modified for use with MPlayer, for details see the changelog at - * http://svn.mplayerhq.hu/mplayer/trunk/ - * $Id$ - */ - -/* -// This is an optimized DCT from Jeff Tsay's maplay 1.2+ package. -// Saved one multiplication by doing the 'twiddle factor' stuff -// together with the window mul. (MH) -// -// This uses Byeong Gi Lee's Fast Cosine Transform algorithm, but the -// 9 point IDCT needs to be reduced further. Unfortunately, I don't -// know how to do that, because 9 is not an even number. - Jeff. -// -////////////////////////////////////////////////////////////////// -// -// 9 Point Inverse Discrete Cosine Transform -// -// This piece of code is Copyright 1997 Mikko Tommila and is freely usable -// by anybody. The algorithm itself is of course in the public domain. -// -// Again derived heuristically from the 9-point WFTA. -// -// The algorithm is optimized (?) for speed, not for small rounding errors or -// good readability. -// -// 36 additions, 11 multiplications -// -// Again this is very likely sub-optimal. -// -// The code is optimized to use a minimum number of temporary variables, -// so it should compile quite well even on 8-register Intel x86 processors. -// This makes the code quite obfuscated and very difficult to understand. -// -// References: -// [1] S. Winograd: "On Computing the Discrete Fourier Transform", -// Mathematics of Computation, Volume 32, Number 141, January 1978, -// Pages 175-199 -*/ - -/*------------------------------------------------------------------*/ -/* */ -/* Function: Calculation of the inverse MDCT */ -/* */ -/*------------------------------------------------------------------*/ - -static void dct36(real *inbuf,real *o1,real *o2,real *wintab,real *tsbuf) -{ -#ifdef NEW_DCT9 - real tmp[18]; -#endif - - { - register real *in = inbuf; - - in[17]+=in[16]; in[16]+=in[15]; in[15]+=in[14]; - in[14]+=in[13]; in[13]+=in[12]; in[12]+=in[11]; - in[11]+=in[10]; in[10]+=in[9]; in[9] +=in[8]; - in[8] +=in[7]; in[7] +=in[6]; in[6] +=in[5]; - in[5] +=in[4]; in[4] +=in[3]; in[3] +=in[2]; - in[2] +=in[1]; in[1] +=in[0]; - - in[17]+=in[15]; in[15]+=in[13]; in[13]+=in[11]; in[11]+=in[9]; - in[9] +=in[7]; in[7] +=in[5]; in[5] +=in[3]; in[3] +=in[1]; - - -#ifdef NEW_DCT9 - { - real t0, t1, t2, t3, t4, t5, t6, t7; - - t1 = COS6_2 * in[12]; - t2 = COS6_2 * (in[8] + in[16] - in[4]); - - t3 = in[0] + t1; - t4 = in[0] - t1 - t1; - t5 = t4 - t2; - - t0 = cos9[0] * (in[4] + in[8]); - t1 = cos9[1] * (in[8] - in[16]); - - tmp[4] = t4 + t2 + t2; - t2 = cos9[2] * (in[4] + in[16]); - - t6 = t3 - t0 - t2; - t0 += t3 + t1; - t3 += t2 - t1; - - t2 = cos18[0] * (in[2] + in[10]); - t4 = cos18[1] * (in[10] - in[14]); - t7 = COS6_1 * in[6]; - - t1 = t2 + t4 + t7; - tmp[0] = t0 + t1; - tmp[8] = t0 - t1; - t1 = cos18[2] * (in[2] + in[14]); - t2 += t1 - t7; - - tmp[3] = t3 + t2; - t0 = COS6_1 * (in[10] + in[14] - in[2]); - tmp[5] = t3 - t2; - - t4 -= t1 + t7; - - tmp[1] = t5 - t0; - tmp[7] = t5 + t0; - tmp[2] = t6 + t4; - tmp[6] = t6 - t4; - } - - { - real t0, t1, t2, t3, t4, t5, t6, t7; - - t1 = COS6_2 * in[13]; - t2 = COS6_2 * (in[9] + in[17] - in[5]); - - t3 = in[1] + t1; - t4 = in[1] - t1 - t1; - t5 = t4 - t2; - - t0 = cos9[0] * (in[5] + in[9]); - t1 = cos9[1] * (in[9] - in[17]); - - tmp[13] = (t4 + t2 + t2) * tfcos36[17-13]; - t2 = cos9[2] * (in[5] + in[17]); - - t6 = t3 - t0 - t2; - t0 += t3 + t1; - t3 += t2 - t1; - - t2 = cos18[0] * (in[3] + in[11]); - t4 = cos18[1] * (in[11] - in[15]); - t7 = COS6_1 * in[7]; - - t1 = t2 + t4 + t7; - tmp[17] = (t0 + t1) * tfcos36[17-17]; - tmp[9] = (t0 - t1) * tfcos36[17-9]; - t1 = cos18[2] * (in[3] + in[15]); - t2 += t1 - t7; - - tmp[14] = (t3 + t2) * tfcos36[17-14]; - t0 = COS6_1 * (in[11] + in[15] - in[3]); - tmp[12] = (t3 - t2) * tfcos36[17-12]; - - t4 -= t1 + t7; - - tmp[16] = (t5 - t0) * tfcos36[17-16]; - tmp[10] = (t5 + t0) * tfcos36[17-10]; - tmp[15] = (t6 + t4) * tfcos36[17-15]; - tmp[11] = (t6 - t4) * tfcos36[17-11]; - } - -#define MACRO(v) { \ - real tmpval; \ - real sum0 = tmp[(v)]; \ - real sum1 = tmp[17-(v)]; \ - out2[9+(v)] = (tmpval = sum0 + sum1) * w[27+(v)]; \ - out2[8-(v)] = tmpval * w[26-(v)]; \ - sum0 -= sum1; \ - ts[SBLIMIT*(8-(v))] = out1[8-(v)] + sum0 * w[8-(v)]; \ - ts[SBLIMIT*(9+(v))] = out1[9+(v)] + sum0 * w[9+(v)]; } - -{ - register real *out2 = o2; - register real *w = wintab; - register real *out1 = o1; - register real *ts = tsbuf; - - MACRO(0); - MACRO(1); - MACRO(2); - MACRO(3); - MACRO(4); - MACRO(5); - MACRO(6); - MACRO(7); - MACRO(8); -} - -#else - - { - -#define MACRO0(v) { \ - real tmp; \ - out2[9+(v)] = (tmp = sum0 + sum1) * w[27+(v)]; \ - out2[8-(v)] = tmp * w[26-(v)]; } \ - sum0 -= sum1; \ - ts[SBLIMIT*(8-(v))] = out1[8-(v)] + sum0 * w[8-(v)]; \ - ts[SBLIMIT*(9+(v))] = out1[9+(v)] + sum0 * w[9+(v)]; -#define MACRO1(v) { \ - real sum0, sum1; \ - sum0 = tmp1a + tmp2a; \ - sum1 = (tmp1b + tmp2b) * tfcos36[(v)]; \ - MACRO0(v); } -#define MACRO2(v) { \ - real sum0, sum1; \ - sum0 = tmp2a - tmp1a; \ - sum1 = (tmp2b - tmp1b) * tfcos36[(v)]; \ - MACRO0(v); } - - register const real *c = COS9; - register real *out2 = o2; - register real *w = wintab; - register real *out1 = o1; - register real *ts = tsbuf; - - real ta33,ta66,tb33,tb66; - - ta33 = in[2*3+0] * c[3]; - ta66 = in[2*6+0] * c[6]; - tb33 = in[2*3+1] * c[3]; - tb66 = in[2*6+1] * c[6]; - - { - real tmp1a,tmp2a,tmp1b,tmp2b; - tmp1a = in[2*1+0] * c[1] + ta33 + in[2*5+0] * c[5] + in[2*7+0] * c[7]; - tmp1b = in[2*1+1] * c[1] + tb33 + in[2*5+1] * c[5] + in[2*7+1] * c[7]; - tmp2a = in[2*0+0] + in[2*2+0] * c[2] + in[2*4+0] * c[4] + ta66 + in[2*8+0] * c[8]; - tmp2b = in[2*0+1] + in[2*2+1] * c[2] + in[2*4+1] * c[4] + tb66 + in[2*8+1] * c[8]; - - MACRO1(0); - MACRO2(8); - } - - { - real tmp1a,tmp2a,tmp1b,tmp2b; - tmp1a = ( in[2*1+0] - in[2*5+0] - in[2*7+0] ) * c[3]; - tmp1b = ( in[2*1+1] - in[2*5+1] - in[2*7+1] ) * c[3]; - tmp2a = ( in[2*2+0] - in[2*4+0] - in[2*8+0] ) * c[6] - in[2*6+0] + in[2*0+0]; - tmp2b = ( in[2*2+1] - in[2*4+1] - in[2*8+1] ) * c[6] - in[2*6+1] + in[2*0+1]; - - MACRO1(1); - MACRO2(7); - } - - { - real tmp1a,tmp2a,tmp1b,tmp2b; - tmp1a = in[2*1+0] * c[5] - ta33 - in[2*5+0] * c[7] + in[2*7+0] * c[1]; - tmp1b = in[2*1+1] * c[5] - tb33 - in[2*5+1] * c[7] + in[2*7+1] * c[1]; - tmp2a = in[2*0+0] - in[2*2+0] * c[8] - in[2*4+0] * c[2] + ta66 + in[2*8+0] * c[4]; - tmp2b = in[2*0+1] - in[2*2+1] * c[8] - in[2*4+1] * c[2] + tb66 + in[2*8+1] * c[4]; - - MACRO1(2); - MACRO2(6); - } - - { - real tmp1a,tmp2a,tmp1b,tmp2b; - tmp1a = in[2*1+0] * c[7] - ta33 + in[2*5+0] * c[1] - in[2*7+0] * c[5]; - tmp1b = in[2*1+1] * c[7] - tb33 + in[2*5+1] * c[1] - in[2*7+1] * c[5]; - tmp2a = in[2*0+0] - in[2*2+0] * c[4] + in[2*4+0] * c[8] + ta66 - in[2*8+0] * c[2]; - tmp2b = in[2*0+1] - in[2*2+1] * c[4] + in[2*4+1] * c[8] + tb66 - in[2*8+1] * c[2]; - - MACRO1(3); - MACRO2(5); - } - - { - real sum0,sum1; - sum0 = in[2*0+0] - in[2*2+0] + in[2*4+0] - in[2*6+0] + in[2*8+0]; - sum1 = (in[2*0+1] - in[2*2+1] + in[2*4+1] - in[2*6+1] + in[2*8+1] ) * tfcos36[4]; - MACRO0(4); - } - } -#endif - - } -} |