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author | Sebastian Dröge <slomo@circular-chaos.org> | 2007-09-06 07:26:45 +0000 |
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committer | Sebastian Dröge <slomo@circular-chaos.org> | 2007-09-06 07:26:45 +0000 |
commit | c9611e6507ffd7b84c70429afdf5d1c16cde11c1 (patch) | |
tree | e8ea15e65154e9f2707c53952c3c7c6eea545c2a /gst/spectrum | |
parent | 76a3fd7100246d47d3dcf08cd1e3370adca244af (diff) | |
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gst/spectrum/fix_fft.c: Remove fixed point FFT as it's not used anymore.
Original commit message from CVS:
* gst/spectrum/fix_fft.c:
Remove fixed point FFT as it's not used anymore.
Diffstat (limited to 'gst/spectrum')
-rw-r--r-- | gst/spectrum/fix_fft.c | 453 |
1 files changed, 0 insertions, 453 deletions
diff --git a/gst/spectrum/fix_fft.c b/gst/spectrum/fix_fft.c deleted file mode 100644 index c453c6ff..00000000 --- a/gst/spectrum/fix_fft.c +++ /dev/null @@ -1,453 +0,0 @@ -/* fix_fft.c - Fixed-point Fast Fourier Transform */ -/* - fix_fft() perform FFT or inverse FFT - window() applies a Hanning window to the (time) input - fix_loud() calculates the loudness of the signal, for - each freq point. Result is an integer array, - units are dB (values will be negative). - iscale() scale an integer value by (numer/denom). - fix_mpy() perform fixed-point multiplication. - Sinewave[1024] sinewave normalized to 32767 (= 1.0). - Loudampl[100] Amplitudes for lopudnesses from 0 to -99 dB. - Low_pass Low-pass filter, cutoff at sample_freq / 4. - - All data are fixed-point short integers, in which - -32768 to +32768 represent -1.0 to +1.0. Integer arithmetic - is used for speed, instead of the more natural floating-point. - - For the forward FFT (time -> freq), fixed scaling is - performed to prevent arithmetic overflow, and to map a 0dB - sine/cosine wave (i.e. amplitude = 32767) to two -6dB freq - coefficients; the one in the lower half is reported as 0dB - by fix_loud(). The return value is always 0. - - For the inverse FFT (freq -> time), fixed scaling cannot be - done, as two 0dB coefficients would sum to a peak amplitude of - 64K, overflowing the 32k range of the fixed-point integers. - Thus, the fix_fft() routine performs variable scaling, and - returns a value which is the number of bits LEFT by which - the output must be shifted to get the actual amplitude - (i.e. if fix_fft() returns 3, each value of fr[] and fi[] - must be multiplied by 8 (2**3) for proper scaling. - Clearly, this cannot be done within the fixed-point short - integers. In practice, if the result is to be used as a - filter, the scale_shift can usually be ignored, as the - result will be approximately correctly normalized as is. - - TURBO C, any memory model; uses inline assembly for speed - and for carefully-scaled arithmetic. - - Written by: Tom Roberts 11/8/89 - Made portable: Malcolm Slaney 12/15/94 malcolm@interval.com - - Timing on a Macintosh PowerBook 180.... (using Symantec C6.0) - fix_fft (1024 points) 8 ticks - fft (1024 points - Using SANE) 112 Ticks - fft (1024 points - Using FPU) 11 - - */ - -#ifdef HAVE_CONFIG_H -#include "config.h" -#endif - -#define fixed short - -/* FIX_MPY() - fixed-point multiplication macro. - Scaling ensures that 32767*32767 = 32767. */ - -#define FIX_MPY(DEST,A,B) DEST = ((long)(A) * (long)(B))>>15 - -#define N_WAVE 1024 /* dimension of Sinewave[] */ -#define LOG2_N_WAVE 10 /* log2(N_WAVE) */ -#define N_LOUD 100 /* dimension of Loudampl[] */ - -extern fixed const gst_spectrum_Sinewave[N_WAVE]; /* placed at end of this file for clarity */ -extern fixed const gst_spectrum_Loudampl[N_LOUD]; - -static int gst_spectrum_db_from_ampl (fixed re, fixed im); -static fixed gst_spectrum_fix_mpy (fixed a, fixed b); - -/* - fix_fft() - perform fast Fourier transform. - - if n>0 FFT is done, if n<0 inverse FFT is done - fr[n],fi[n] are real,imaginary arrays, INPUT AND RESULT. - size of data = 2**m - set inverse to 0=dft, 1=idft - */ -int -gst_spectrum_fix_fft (fixed fr[], fixed fi[], int m, int inverse) -{ - int mr, nn, i, j, l, k, istep, n, scale, shift; - fixed qr, qi, tr, ti, wr, wi; - - n = 1 << m; - - if (n > N_WAVE) - return -1; - - mr = 0; - nn = n - 1; - scale = 0; - - /* decimation in time - re-order data */ - for (m = 1; m <= nn; ++m) { - l = n; - do { - l >>= 1; - } - while (mr + l > nn); - mr = (mr & (l - 1)) + l; - - if (mr <= m) - continue; - tr = fr[m]; - fr[m] = fr[mr]; - fr[mr] = tr; - ti = fi[m]; - fi[m] = fi[mr]; - fi[mr] = ti; - } - - l = 1; - k = LOG2_N_WAVE - 1; - while (l < n) { - if (inverse) { - /* variable scaling, depending upon data */ - shift = 0; - for (i = 0; i < n; ++i) { - j = fr[i]; - if (j < 0) - j = -j; - m = fi[i]; - if (m < 0) - m = -m; - if (j > 16383 || m > 16383) { - shift = 1; - break; - } - } - if (shift) - ++scale; - } else { - /* fixed scaling, for proper normalization - - there will be log2(n) passes, so this - results in an overall factor of 1/n, - distributed to maximize arithmetic accuracy. */ - shift = 1; - } - /* it may not be obvious, but the shift will be performed - on each data point exactly once, during this pass. */ - istep = l << 1; - for (m = 0; m < l; ++m) { - j = m << k; - /* 0 <= j < N_WAVE/2 */ - wr = gst_spectrum_Sinewave[j + N_WAVE / 4]; - wi = -gst_spectrum_Sinewave[j]; - if (inverse) - wi = -wi; - if (shift) { - wr >>= 1; - wi >>= 1; - } - for (i = m; i < n; i += istep) { - j = i + l; - tr = gst_spectrum_fix_mpy (wr, fr[j]) - - gst_spectrum_fix_mpy (wi, fi[j]); - ti = gst_spectrum_fix_mpy (wr, fi[j]) + - gst_spectrum_fix_mpy (wi, fr[j]); - qr = fr[i]; - qi = fi[i]; - if (shift) { - qr >>= 1; - qi >>= 1; - } - fr[j] = qr - tr; - fi[j] = qi - ti; - fr[i] = qr + tr; - fi[i] = qi + ti; - } - } - --k; - l = istep; - } - - return scale; -} - -/* window() - apply a Hanning window */ -void -gst_spectrum_window (fixed fr[], int n) -{ - int i, j, k; - - j = N_WAVE / n; - n >>= 1; - for (i = 0, k = N_WAVE / 4; i < n; ++i, k += j) - FIX_MPY (fr[i], fr[i], 16384 - (gst_spectrum_Sinewave[k] >> 1)); - n <<= 1; - for (k -= j; i < n; ++i, k -= j) - FIX_MPY (fr[i], fr[i], 16384 - (gst_spectrum_Sinewave[k] >> 1)); -} - -/* fix_loud() - compute loudness of freq-vis components. - n should be ntot/2, where ntot was passed to fix_fft(); - 6 dB is added to account for the omitted alias components. - scale_shift should be the result of fix_fft(), if the time-series - was obtained from an inverse FFT, 0 otherwise. - loud[] is the loudness, in dB wrt 32767; will be +10 to -N_LOUD. - */ -void -gst_spectrum_fix_loud (fixed loud[], fixed fr[], fixed fi[], int n, - int scale_shift) -{ - int i, max; - - max = 0; - if (scale_shift > 0) - max = 10; - scale_shift = (scale_shift + 1) * 6; - - for (i = 0; i < n; ++i) { - loud[i] = gst_spectrum_db_from_ampl (fr[i], fi[i]) + scale_shift; - if (loud[i] > max) - loud[i] = max; - } -} - -/* db_from_ampl() - find loudness (in dB) from - the complex amplitude. - */ -static int -gst_spectrum_db_from_ampl (fixed re, fixed im) -{ - static long loud2[N_LOUD] = { 0 }; - long v; - int i; - - if (loud2[0] == 0) { - loud2[0] = - (long) gst_spectrum_Loudampl[0] * (long) gst_spectrum_Loudampl[0]; - for (i = 1; i < N_LOUD; ++i) { - v = (long) gst_spectrum_Loudampl[i] * (long) gst_spectrum_Loudampl[i]; - loud2[i] = v; - loud2[i - 1] = (loud2[i - 1] + v) / 2; - } - } - - v = (long) re *(long) re + (long) im *(long) im; - - for (i = 0; i < N_LOUD; ++i) - if (loud2[i] <= v) - break; - - return (-i); -} - -/* - fix_mpy() - fixed-point multiplication - */ -static fixed -gst_spectrum_fix_mpy (fixed a, fixed b) -{ - FIX_MPY (a, a, b); - return a; -} - -#if 0 -/* - iscale() - scale an integer value by (numer/denom) - */ -static int -gst_spectrum_iscale (int value, int numer, int denom) -{ - return (long) value *(long) numer / (long) denom; -} - -/* - fix_dot() - dot product of two fixed arrays - */ -static fixed -gst_spectrum_fix_dot (fixed * hpa, fixed * pb, int n) -{ - fixed *pa = hpa; /* FIXME */ - long sum; - register fixed a, b; - - /* - seg = FP_SEG(hpa); - off = FP_OFF(hpa); - seg += off>>4; - off &= 0x000F; - pa = MK_FP(seg,off); - */ - sum = 0L; - while (n--) { - a = *pa++; - b = *pb++; - FIX_MPY (a, a, b); - sum += a; - } - - if (sum > 0x7FFF) - sum = 0x7FFF; - else if (sum < -0x7FFF) - sum = -0x7FFF; - - return (fixed) sum; - -} -#endif - -#if N_WAVE != 1024 -ERROR:N_WAVE != 1024 -#endif -fixed const gst_spectrum_Sinewave[1024] = { - 0, 201, 402, 603, 804, 1005, 1206, 1406, - 1607, 1808, 2009, 2209, 2410, 2610, 2811, 3011, - 3211, 3411, 3611, 3811, 4011, 4210, 4409, 4608, - 4807, 5006, 5205, 5403, 5601, 5799, 5997, 6195, - 6392, 6589, 6786, 6982, 7179, 7375, 7571, 7766, - 7961, 8156, 8351, 8545, 8739, 8932, 9126, 9319, - 9511, 9703, 9895, 10087, 10278, 10469, 10659, 10849, - 11038, 11227, 11416, 11604, 11792, 11980, 12166, 12353, - 12539, 12724, 12909, 13094, 13278, 13462, 13645, 13827, - 14009, 14191, 14372, 14552, 14732, 14911, 15090, 15268, - 15446, 15623, 15799, 15975, 16150, 16325, 16499, 16672, - 16845, 17017, 17189, 17360, 17530, 17699, 17868, 18036, - 18204, 18371, 18537, 18702, 18867, 19031, 19194, 19357, - 19519, 19680, 19840, 20000, 20159, 20317, 20474, 20631, - 20787, 20942, 21096, 21249, 21402, 21554, 21705, 21855, - 22004, 22153, 22301, 22448, 22594, 22739, 22883, 23027, - 23169, 23311, 23452, 23592, 23731, 23869, 24006, 24143, - 24278, 24413, 24546, 24679, 24811, 24942, 25072, 25201, - 25329, 25456, 25582, 25707, 25831, 25954, 26077, 26198, - 26318, 26437, 26556, 26673, 26789, 26905, 27019, 27132, - 27244, 27355, 27466, 27575, 27683, 27790, 27896, 28001, - 28105, 28208, 28309, 28410, 28510, 28608, 28706, 28802, - 28897, 28992, 29085, 29177, 29268, 29358, 29446, 29534, - 29621, 29706, 29790, 29873, 29955, 30036, 30116, 30195, - 30272, 30349, 30424, 30498, 30571, 30643, 30713, 30783, - 30851, 30918, 30984, 31049, - 31113, 31175, 31236, 31297, - 31356, 31413, 31470, 31525, 31580, 31633, 31684, 31735, - 31785, 31833, 31880, 31926, 31970, 32014, 32056, 32097, - 32137, 32176, 32213, 32249, 32284, 32318, 32350, 32382, - 32412, 32441, 32468, 32495, 32520, 32544, 32567, 32588, - 32609, 32628, 32646, 32662, 32678, 32692, 32705, 32717, - 32727, 32736, 32744, 32751, 32757, 32761, 32764, 32766, - 32767, 32766, 32764, 32761, 32757, 32751, 32744, 32736, - 32727, 32717, 32705, 32692, 32678, 32662, 32646, 32628, - 32609, 32588, 32567, 32544, 32520, 32495, 32468, 32441, - 32412, 32382, 32350, 32318, 32284, 32249, 32213, 32176, - 32137, 32097, 32056, 32014, 31970, 31926, 31880, 31833, - 31785, 31735, 31684, 31633, 31580, 31525, 31470, 31413, - 31356, 31297, 31236, 31175, 31113, 31049, 30984, 30918, - 30851, 30783, 30713, 30643, 30571, 30498, 30424, 30349, - 30272, 30195, 30116, 30036, 29955, 29873, 29790, 29706, - 29621, 29534, 29446, 29358, 29268, 29177, 29085, 28992, - 28897, 28802, 28706, 28608, 28510, 28410, 28309, 28208, - 28105, 28001, 27896, 27790, 27683, 27575, 27466, 27355, - 27244, 27132, 27019, 26905, 26789, 26673, 26556, 26437, - 26318, 26198, 26077, 25954, 25831, 25707, 25582, 25456, - 25329, 25201, 25072, 24942, 24811, 24679, 24546, 24413, - 24278, 24143, 24006, 23869, 23731, 23592, 23452, 23311, - 23169, 23027, 22883, 22739, 22594, 22448, 22301, 22153, - 22004, 21855, 21705, 21554, 21402, 21249, 21096, 20942, - 20787, 20631, 20474, 20317, 20159, 20000, 19840, 19680, - 19519, 19357, 19194, 19031, 18867, 18702, 18537, 18371, - 18204, 18036, 17868, 17699, 17530, 17360, 17189, 17017, - 16845, 16672, 16499, 16325, 16150, 15975, 15799, 15623, - 15446, 15268, 15090, 14911, 14732, 14552, 14372, 14191, - 14009, 13827, 13645, 13462, 13278, 13094, 12909, 12724, - 12539, 12353, 12166, 11980, 11792, 11604, 11416, 11227, - 11038, 10849, 10659, 10469, 10278, 10087, 9895, 9703, - 9511, 9319, 9126, 8932, 8739, 8545, 8351, 8156, - 7961, 7766, 7571, 7375, 7179, 6982, 6786, 6589, - 6392, 6195, 5997, 5799, 5601, 5403, 5205, 5006, - 4807, 4608, 4409, 4210, 4011, 3811, 3611, 3411, - 3211, 3011, 2811, 2610, 2410, 2209, 2009, 1808, - 1607, 1406, 1206, 1005, 804, 603, 402, 201, - 0, -201, -402, -603, -804, -1005, -1206, -1406, - -1607, -1808, -2009, -2209, -2410, -2610, -2811, -3011, - -3211, -3411, -3611, -3811, -4011, -4210, -4409, -4608, - -4807, -5006, -5205, -5403, -5601, -5799, -5997, -6195, - -6392, -6589, -6786, -6982, -7179, -7375, -7571, -7766, - -7961, -8156, -8351, -8545, -8739, -8932, -9126, -9319, - -9511, -9703, -9895, -10087, -10278, -10469, -10659, -10849, - -11038, -11227, -11416, -11604, -11792, -11980, -12166, -12353, - -12539, -12724, -12909, -13094, -13278, -13462, -13645, -13827, - -14009, -14191, -14372, -14552, -14732, -14911, -15090, -15268, - -15446, -15623, -15799, -15975, -16150, -16325, -16499, -16672, - -16845, -17017, -17189, -17360, -17530, -17699, -17868, -18036, - -18204, -18371, -18537, -18702, -18867, -19031, -19194, -19357, - -19519, -19680, -19840, -20000, -20159, -20317, -20474, -20631, - -20787, -20942, -21096, -21249, -21402, -21554, -21705, -21855, - -22004, -22153, -22301, -22448, -22594, -22739, -22883, -23027, - -23169, -23311, -23452, -23592, -23731, -23869, -24006, -24143, - -24278, -24413, -24546, -24679, -24811, -24942, -25072, -25201, - -25329, -25456, -25582, -25707, -25831, -25954, -26077, -26198, - -26318, -26437, -26556, -26673, -26789, -26905, -27019, -27132, - -27244, -27355, -27466, -27575, -27683, -27790, -27896, -28001, - -28105, -28208, -28309, -28410, -28510, -28608, -28706, -28802, - -28897, -28992, -29085, -29177, -29268, -29358, -29446, -29534, - -29621, -29706, -29790, -29873, -29955, -30036, -30116, -30195, - -30272, -30349, -30424, -30498, -30571, -30643, -30713, -30783, - -30851, -30918, -30984, -31049, -31113, -31175, -31236, -31297, - -31356, -31413, -31470, -31525, -31580, -31633, -31684, -31735, - -31785, -31833, -31880, -31926, -31970, -32014, -32056, -32097, - -32137, -32176, -32213, -32249, -32284, -32318, -32350, -32382, - -32412, -32441, -32468, -32495, -32520, -32544, -32567, -32588, - -32609, -32628, -32646, -32662, -32678, -32692, -32705, -32717, - -32727, -32736, -32744, -32751, -32757, -32761, -32764, -32766, - -32767, -32766, -32764, -32761, -32757, -32751, -32744, -32736, - -32727, -32717, -32705, -32692, -32678, -32662, -32646, -32628, - -32609, -32588, -32567, -32544, -32520, -32495, -32468, -32441, - -32412, -32382, -32350, -32318, -32284, -32249, -32213, -32176, - -32137, -32097, -32056, -32014, -31970, -31926, -31880, -31833, - -31785, -31735, -31684, -31633, -31580, -31525, -31470, -31413, - -31356, -31297, -31236, -31175, -31113, -31049, -30984, -30918, - -30851, -30783, -30713, -30643, -30571, -30498, -30424, -30349, - -30272, -30195, -30116, -30036, -29955, -29873, -29790, -29706, - -29621, -29534, -29446, -29358, -29268, -29177, -29085, -28992, - -28897, -28802, -28706, -28608, -28510, -28410, -28309, -28208, - -28105, -28001, -27896, -27790, -27683, -27575, -27466, -27355, - -27244, -27132, -27019, -26905, -26789, -26673, -26556, -26437, - -26318, -26198, -26077, -25954, -25831, -25707, -25582, -25456, - -25329, -25201, -25072, -24942, -24811, -24679, -24546, -24413, - -24278, -24143, -24006, -23869, -23731, -23592, -23452, -23311, - -23169, -23027, -22883, -22739, -22594, -22448, -22301, -22153, - -22004, -21855, -21705, -21554, -21402, -21249, -21096, -20942, - -20787, -20631, -20474, -20317, -20159, -20000, -19840, -19680, - -19519, -19357, -19194, -19031, -18867, -18702, -18537, -18371, - -18204, -18036, -17868, -17699, -17530, -17360, -17189, -17017, - -16845, -16672, -16499, -16325, -16150, -15975, -15799, -15623, - -15446, -15268, -15090, -14911, -14732, -14552, -14372, -14191, - -14009, -13827, -13645, -13462, -13278, -13094, -12909, -12724, - -12539, -12353, -12166, -11980, -11792, -11604, -11416, -11227, - -11038, -10849, -10659, -10469, -10278, -10087, -9895, -9703, - -9511, -9319, -9126, -8932, -8739, -8545, -8351, -8156, - -7961, -7766, -7571, -7375, -7179, -6982, -6786, -6589, - -6392, -6195, -5997, -5799, -5601, -5403, -5205, -5006, - -4807, -4608, -4409, -4210, -4011, -3811, -3611, -3411, - -3211, -3011, -2811, -2610, -2410, -2209, -2009, -1808, - -1607, -1406, -1206, -1005, -804, -603, -402, -201, -}; - -#if N_LOUD != 100 -ERROR:N_LOUD != 100 -#endif -fixed const gst_spectrum_Loudampl[100] = { - 32767, 29203, 26027, 23197, 20674, 18426, 16422, 14636, - 13044, 11626, 10361, 9234, 8230, 7335, 6537, 5826, - 5193, 4628, 4125, 3676, 3276, 2920, 2602, 2319, - 2067, 1842, 1642, 1463, 1304, 1162, 1036, 923, - 823, 733, 653, 582, 519, 462, 412, 367, - 327, 292, 260, 231, 206, 184, 164, 146, - 130, 116, 103, 92, 82, 73, 65, 58, - 51, 46, 41, 36, 32, 29, 26, 23, - 20, 18, 16, 14, 13, 11, 10, 9, - 8, 7, 6, 5, 5, 4, 4, 3, - 3, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -}; |