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author | Klaus Schmidinger <kls (at) cadsoft (dot) de> | 2001-08-12 18:00:00 +0200 |
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committer | Klaus Schmidinger <kls (at) cadsoft (dot) de> | 2001-08-12 18:00:00 +0200 |
commit | efea0f64d08052b0189d962101e1a3634d4adfc8 (patch) | |
tree | a3feff7ccf6874da549b25ea3b671d15a65d0e3d /ac3dec/srfft.c | |
parent | f1d1c9849c8e27cccb46cf9c0d0ccb59da3f91f9 (diff) | |
download | vdr-patch-lnbsharing-efea0f64d08052b0189d962101e1a3634d4adfc8.tar.gz vdr-patch-lnbsharing-efea0f64d08052b0189d962101e1a3634d4adfc8.tar.bz2 |
Version 0.91vdr-0.91
- Fixed displaying colored button texts that are too long.
- Suppressing replay progress display when replaying a DVD.
- Updated channels.conf.cable (thanks to Uwe Scheffler).
- Updated French OSD texts (thanks to Jean-Claude Repetto).
- Improved AC3 decoding when replaying DVDs (thanks to Matjaz Thaler).
- Fixed handling DVB card indexes when using only one card in a multi-card
system.
- Changed the 'Eject DVD' button text to a simple 'Eject' (the German text
was too long...).
- Made the font file generation more stable (thanks to Artur Skawina).
- Changed the default value for the "DiSEqC" setup parameter to "off".
- The new command line option '-E' can be used to define where the EPG data
shall be written to. This is especially useful if VDR runs in a system
that turns off the video disk when it is not used, and therefore needs
to write the EPG file to a ramdisk (or turn off writing it alltogether).
See 'vdr --help' for details.
- Making sure the disk is up and running before starting recording (this
is important for systems that turn off the video disk when it is not used).
- Added the "Jump" function in replay mode (thanks to Stefan Huelswitt).
See the description of the "Red" key in MANUAL under "Replay Control" for
details.
- Fixed displaying editing marks when toggling a mark in "pause" mode.
- If there is no free DVB device to record, the log message will now be given
only once.
- Made I/O more robust by handling EINTR (thanks to Werner Fink).
Diffstat (limited to 'ac3dec/srfft.c')
-rw-r--r-- | ac3dec/srfft.c | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/ac3dec/srfft.c b/ac3dec/srfft.c new file mode 100644 index 0000000..4cbb629 --- /dev/null +++ b/ac3dec/srfft.c @@ -0,0 +1,305 @@ +/* + * srfft.c + * + * Copyright (C) Yuqing Deng <Yuqing_Deng@brown.edu> - April 2000 + * + * 64 and 128 point split radix fft for ac3dec + * + * The algorithm is desribed in the book: + * "Computational Frameworks of the Fast Fourier Transform". + * + * The ideas and the the organization of code borrowed from djbfft written by + * D. J. Bernstein <djb@cr.py.to>. djbff can be found at + * http://cr.yp.to/djbfft.html. + * + * srfft.c is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * srfft.c is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GNU Make; see the file COPYING. If not, write to + * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ + +#include <stdio.h> + +#include "srfft.h" +#include "srfftp.h" + +void fft_8 (complex_t *x); + +void fft_4(complex_t *x) +{ + /* delta_p = 1 here */ + /* x[k] = sum_{i=0..3} x[i] * w^{i*k}, w=e^{-2*pi/4} + */ + + register float yt_r, yt_i, yb_r, yb_i, u_r, u_i, vi_r, vi_i; + + yt_r = x[0].re; + yb_r = yt_r - x[2].re; + yt_r += x[2].re; + + u_r = x[1].re; + vi_i = x[3].re - u_r; + u_r += x[3].re; + + u_i = x[1].im; + vi_r = u_i - x[3].im; + u_i += x[3].im; + + yt_i = yt_r; + yt_i += u_r; + x[0].re = yt_i; + yt_r -= u_r; + x[2].re = yt_r; + yt_i = yb_r; + yt_i += vi_r; + x[1].re = yt_i; + yb_r -= vi_r; + x[3].re = yb_r; + + yt_i = x[0].im; + yb_i = yt_i - x[2].im; + yt_i += x[2].im; + + yt_r = yt_i; + yt_r += u_i; + x[0].im = yt_r; + yt_i -= u_i; + x[2].im = yt_i; + yt_r = yb_i; + yt_r += vi_i; + x[1].im = yt_r; + yb_i -= vi_i; + x[3].im = yb_i; +} + + +void fft_8 (complex_t *x) +{ + /* delta_p = diag{1, sqrt(i)} here */ + /* x[k] = sum_{i=0..7} x[i] * w^{i*k}, w=e^{-2*pi/8} + */ + register float wT1_r, wT1_i, wB1_r, wB1_i, wT2_r, wT2_i, wB2_r, wB2_i; + + wT1_r = x[1].re; + wT1_i = x[1].im; + wB1_r = x[3].re; + wB1_i = x[3].im; + + x[1] = x[2]; + x[2] = x[4]; + x[3] = x[6]; + fft_4(&x[0]); + + + /* x[0] x[4] */ + wT2_r = x[5].re; + wT2_r += x[7].re; + wT2_r += wT1_r; + wT2_r += wB1_r; + wT2_i = wT2_r; + wT2_r += x[0].re; + wT2_i = x[0].re - wT2_i; + x[0].re = wT2_r; + x[4].re = wT2_i; + + wT2_i = x[5].im; + wT2_i += x[7].im; + wT2_i += wT1_i; + wT2_i += wB1_i; + wT2_r = wT2_i; + wT2_r += x[0].im; + wT2_i = x[0].im - wT2_i; + x[0].im = wT2_r; + x[4].im = wT2_i; + + /* x[2] x[6] */ + wT2_r = x[5].im; + wT2_r -= x[7].im; + wT2_r += wT1_i; + wT2_r -= wB1_i; + wT2_i = wT2_r; + wT2_r += x[2].re; + wT2_i = x[2].re - wT2_i; + x[2].re = wT2_r; + x[6].re = wT2_i; + + wT2_i = x[5].re; + wT2_i -= x[7].re; + wT2_i += wT1_r; + wT2_i -= wB1_r; + wT2_r = wT2_i; + wT2_r += x[2].im; + wT2_i = x[2].im - wT2_i; + x[2].im = wT2_i; + x[6].im = wT2_r; + + + /* x[1] x[5] */ + wT2_r = wT1_r; + wT2_r += wB1_i; + wT2_r -= x[5].re; + wT2_r -= x[7].im; + wT2_i = wT1_i; + wT2_i -= wB1_r; + wT2_i -= x[5].im; + wT2_i += x[7].re; + + wB2_r = wT2_r; + wB2_r += wT2_i; + wT2_i -= wT2_r; + wB2_r *= HSQRT2; + wT2_i *= HSQRT2; + wT2_r = wB2_r; + wB2_r += x[1].re; + wT2_r = x[1].re - wT2_r; + + wB2_i = x[5].re; + x[1].re = wB2_r; + x[5].re = wT2_r; + + wT2_r = wT2_i; + wT2_r += x[1].im; + wT2_i = x[1].im - wT2_i; + wB2_r = x[5].im; + x[1].im = wT2_r; + x[5].im = wT2_i; + + /* x[3] x[7] */ + wT1_r -= wB1_i; + wT1_i += wB1_r; + wB1_r = wB2_i - x[7].im; + wB1_i = wB2_r + x[7].re; + wT1_r -= wB1_r; + wT1_i -= wB1_i; + wB1_r = wT1_r + wT1_i; + wB1_r *= HSQRT2; + wT1_i -= wT1_r; + wT1_i *= HSQRT2; + wB2_r = x[3].re; + wB2_i = wB2_r + wT1_i; + wB2_r -= wT1_i; + x[3].re = wB2_i; + x[7].re = wB2_r; + wB2_i = x[3].im; + wB2_r = wB2_i + wB1_r; + wB2_i -= wB1_r; + x[3].im = wB2_i; + x[7].im = wB2_r; +} + + +void fft_asmb(int k, complex_t *x, complex_t *wTB, + const complex_t *d, const complex_t *d_3) +{ + register complex_t *x2k, *x3k, *x4k, *wB; + register float a_r, a_i, a1_r, a1_i, u_r, u_i, v_r, v_i; + + x2k = x + 2 * k; + x3k = x2k + 2 * k; + x4k = x3k + 2 * k; + wB = wTB + 2 * k; + + TRANSZERO(x[0],x2k[0],x3k[0],x4k[0]); + TRANS(x[1],x2k[1],x3k[1],x4k[1],wTB[1],wB[1],d[1],d_3[1]); + + --k; + for(;;) { + TRANS(x[2],x2k[2],x3k[2],x4k[2],wTB[2],wB[2],d[2],d_3[2]); + TRANS(x[3],x2k[3],x3k[3],x4k[3],wTB[3],wB[3],d[3],d_3[3]); + if (!--k) break; + x += 2; + x2k += 2; + x3k += 2; + x4k += 2; + d += 2; + d_3 += 2; + wTB += 2; + wB += 2; + } + +} + +void fft_asmb16(complex_t *x, complex_t *wTB) +{ + register float a_r, a_i, a1_r, a1_i, u_r, u_i, v_r, v_i; + int k = 2; + + /* transform x[0], x[8], x[4], x[12] */ + TRANSZERO(x[0],x[4],x[8],x[12]); + + /* transform x[1], x[9], x[5], x[13] */ + TRANS(x[1],x[5],x[9],x[13],wTB[1],wTB[5],delta16[1],delta16_3[1]); + + /* transform x[2], x[10], x[6], x[14] */ + TRANSHALF_16(x[2],x[6],x[10],x[14]); + + /* transform x[3], x[11], x[7], x[15] */ + TRANS(x[3],x[7],x[11],x[15],wTB[3],wTB[7],delta16[3],delta16_3[3]); + +} + + +void fft_64p_c (complex_t *a) +{ + fft_8(&a[0]); fft_4(&a[8]); fft_4(&a[12]); + fft_asmb16(&a[0], &a[8]); + + fft_8(&a[16]), fft_8(&a[24]); + fft_asmb(4, &a[0], &a[16],&delta32[0], &delta32_3[0]); + + fft_8(&a[32]); fft_4(&a[40]); fft_4(&a[44]); + fft_asmb16(&a[32], &a[40]); + + fft_8(&a[48]); fft_4(&a[56]); fft_4(&a[60]); + fft_asmb16(&a[48], &a[56]); + + fft_asmb(8, &a[0], &a[32],&delta64[0], &delta64_3[0]); +} + + +void fft_128p_c (complex_t *a) +{ + fft_8(&a[0]); fft_4(&a[8]); fft_4(&a[12]); + fft_asmb16(&a[0], &a[8]); + + fft_8(&a[16]), fft_8(&a[24]); + fft_asmb(4, &a[0], &a[16],&delta32[0], &delta32_3[0]); + + fft_8(&a[32]); fft_4(&a[40]); fft_4(&a[44]); + fft_asmb16(&a[32], &a[40]); + + fft_8(&a[48]); fft_4(&a[56]); fft_4(&a[60]); + fft_asmb16(&a[48], &a[56]); + + fft_asmb(8, &a[0], &a[32],&delta64[0], &delta64_3[0]); + + fft_8(&a[64]); fft_4(&a[72]); fft_4(&a[76]); + /* fft_16(&a[64]); */ + fft_asmb16(&a[64], &a[72]); + + fft_8(&a[80]); fft_8(&a[88]); + + /* fft_32(&a[64]); */ + fft_asmb(4, &a[64], &a[80],&delta32[0], &delta32_3[0]); + + fft_8(&a[96]); fft_4(&a[104]), fft_4(&a[108]); + /* fft_16(&a[96]); */ + fft_asmb16(&a[96], &a[104]); + + fft_8(&a[112]), fft_8(&a[120]); + /* fft_32(&a[96]); */ + fft_asmb(4, &a[96], &a[112], &delta32[0], &delta32_3[0]); + + /* fft_128(&a[0]); */ + fft_asmb(16, &a[0], &a[64], &delta128[0], &delta128_3[0]); +} |