Initial revision

Original commit message from CVS:
Initial revision

6 files changed, 783 insertions, 0 deletions

diff --git a/gst/spectrum/.gitignore b/gst/spectrum/.gitignore
new file mode 100644
index 00000000..08f5ed37
--- /dev/null
+++ b/gst/spectrum/.gitignore
@@ -0,0 +1,7 @@
+Makefile
+Makefile.in
+*.o
+*.lo
+*.la
+.deps
+.libs
diff --git a/gst/spectrum/Makefile.am b/gst/spectrum/Makefile.am
new file mode 100644
index 00000000..476c3fd1
--- /dev/null
+++ b/gst/spectrum/Makefile.am
@@ -0,0 +1,10 @@
+filterdir = $(libdir)/gst
+
+filter_LTLIBRARIES = libgstspectrum.la
+
+libgstspectrum_la_SOURCES = gstspectrum.c fix_fft.c
+libgstspectrum_la_CFLAGS = $(GST_CFLAGS)
+
+noinst_HEADERS = gstspectrum.h
+
+EXTRA_DIST = README
diff --git a/gst/spectrum/README b/gst/spectrum/README
new file mode 100644
index 00000000..87555712
--- /dev/null
+++ b/gst/spectrum/README
@@ -0,0 +1,5 @@
+This is a simple, rather lame spectrum analyzer made from the fix_fft.c
+code, as found I think in xmms-0.9.1 (the 75-wide output sounds like xmms
+to me), which is actually written by other people (see fix_fft.c for
+credits).  It worked last time I had GiST working, which was a while ago.
+Yes, GiST is not included here yet, it will be in 0.1.0.
diff --git a/gst/spectrum/fix_fft.c b/gst/spectrum/fix_fft.c
new file mode 100644
index 00000000..ecd70303
--- /dev/null
+++ b/gst/spectrum/fix_fft.c
@@ -0,0 +1,452 @@
+/*      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
+
+ */
+
+#define fixed short
+
+/* FIX_MPY() - fixed-point multiplication macro.
+   This macro is a statement, not an expression (uses asm).
+   BEWARE: make sure _DX is not clobbered by evaluating (A) or DEST.
+   args are all of type fixed.
+   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 gst_spectrum_Sinewave[N_WAVE];	/* placed at end of this file for clarity */
+extern fixed 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, t;
+
+	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.
+ */
+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
+ */
+fixed gst_spectrum_fix_mpy(fixed a, fixed b) {
+	FIX_MPY(a, a, b);
+	return a;
+}
+
+/*
+   iscale() - scale an integer value by (numer/denom)
+ */
+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
+ */
+fixed gst_spectrum_fix_dot(fixed * hpa, fixed * pb, int n) {
+	fixed *pa;
+	long sum;
+	register fixed a, b;
+	unsigned int seg, off;
+
+/*      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;
+
+}
+
+#if N_WAVE != 1024
+ERROR:N_WAVE != 1024
+#endif
+fixed 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 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,
+};
diff --git a/gst/spectrum/gstspectrum.c b/gst/spectrum/gstspectrum.c
new file mode 100644
index 00000000..0821545c
--- /dev/null
+++ b/gst/spectrum/gstspectrum.c
@@ -0,0 +1,242 @@
+/* Gnome-Streamer
+ * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <string.h>
+
+#include "gstspectrum.h"
+
+static GstElementDetails gst_spectrum_details = {
+  "Spectrum analyzer",
+  "Filter/Analysis",
+  "Run an FFT on the audio signal, output spectrum data",
+  VERSION,
+  "Erik Walthinsen <omega@cse.ogi.edu>",
+  "(C) 1999",
+};
+
+
+static GstTypeDefinition spectrumdefinition = {
+  "spectrum_spectrum_raw",
+  "spectrum/raw",
+  NULL,
+  NULL,
+};
+
+
+/* Spectrum signals and args */
+enum {
+  /* FILL ME */
+  LAST_SIGNAL
+};
+
+enum {
+  ARG_0,
+  ARG_WIDTH,
+};
+
+
+static void	gst_spectrum_class_init	(GstSpectrumClass *klass);
+static void	gst_spectrum_init	(GstSpectrum *spectrum);
+
+static void	gst_spectrum_set_property	(GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
+
+static void	gst_spectrum_chain	(GstPad *pad, GstBuffer *buf);
+
+#define fixed short
+int gst_spectrum_fix_fft(fixed fr[], fixed fi[], int m, int inverse);
+void gst_spectrum_fix_loud(fixed loud[], fixed fr[], fixed fi[], int n, int scale_shift);
+void gst_spectrum_window(fixed fr[], int n);
+
+
+static GstElementClass *parent_class = NULL;
+//static guint gst_spectrum_signals[LAST_SIGNAL] = { 0 };
+
+GType
+gst_spectrum_get_type (void)
+{
+  static GType spectrum_type = 0;
+
+  if (!spectrum_type) {
+    static const GTypeInfo spectrum_info = {
+      sizeof(GstSpectrumClass),      NULL,
+      NULL,
+      (GClassInitFunc)gst_spectrum_class_init,
+      NULL,
+      NULL,
+      sizeof(GstSpectrum),
+      0,
+      (GInstanceInitFunc)gst_spectrum_init,
+    };
+    spectrum_type = g_type_register_static(GST_TYPE_ELEMENT, "GstSpectrum", &spectrum_info, 0);
+  }
+  return spectrum_type;
+}
+
+static void
+gst_spectrum_class_init (GstSpectrumClass *klass)
+{
+  GObjectClass *gobject_class;
+
+  gobject_class = (GObjectClass*)klass;
+
+  parent_class = g_type_class_ref(GST_TYPE_ELEMENT);
+
+  g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_WIDTH,
+    g_param_spec_int("width","width","width",
+                     G_MININT,G_MAXINT,0,G_PARAM_WRITABLE)); // CHECKME
+
+  gobject_class->set_property = gst_spectrum_set_property;
+}
+
+static void
+gst_spectrum_init (GstSpectrum *spectrum)
+{
+  spectrum->sinkpad = gst_pad_new("sink",GST_PAD_SINK);
+  gst_element_add_pad(GST_ELEMENT(spectrum),spectrum->sinkpad);
+  gst_pad_set_chain_function(spectrum->sinkpad,gst_spectrum_chain);
+  spectrum->srcpad = gst_pad_new("src",GST_PAD_SRC);
+  gst_element_add_pad(GST_ELEMENT(spectrum),spectrum->srcpad);
+
+  spectrum->width = 75;
+}
+
+static void
+gst_spectrum_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+{
+  GstSpectrum *spectrum;
+
+  /* it's not null if we got it, but it might not be ours */
+  g_return_if_fail(GST_IS_SPECTRUM(object));
+  spectrum = GST_SPECTRUM(object);
+
+  switch (prop_id) {
+    case ARG_WIDTH:
+      spectrum->width = g_value_get_int (value);
+      break;
+    default:
+      break;
+  }
+}
+
+static void
+gst_spectrum_chain (GstPad *pad, GstBuffer *buf)
+{
+  GstSpectrum *spectrum;
+  gint spec_base, spec_len;
+  gint16 *re, *im, *loud;
+  gint16 *samples;
+  gint samplecount,step,pos,i;
+  guchar *spect;
+  GstBuffer *newbuf;
+
+  g_return_if_fail(pad != NULL);
+  g_return_if_fail(GST_IS_PAD(pad));
+  g_return_if_fail(buf != NULL);
+
+  spectrum = GST_SPECTRUM (GST_OBJECT_PARENT (pad));
+
+  /* first deal with audio metadata */
+//  FIXME
+//  if (buf->meta) {
+//    if (spectrum->meta != NULL) {
+//      /* FIXME: need to unref the old metadata so it goes away */
+//    }
+//    /* we just make a copy of the pointer */
+//    spectrum->meta = (MetaAudioRaw *)(buf->data);
+//    /* FIXME: now we have to ref the metadata so it does go away */
+//  }
+
+  //g_return_if_fail(spectrum->meta != NULL);
+
+  //samplecount = GST_BUFFER_SIZE(buf) /
+  //              (spectrum->meta->channels * sizeof(gint16));
+//  samples = (gint16 *)g_malloc(buf->datasize);
+//  g_return_if_fail(samples != NULL);
+//  memcpy(samples,(gint16
+//*)GST_BUFFER_DATA(buf),GST_BUFFER_DATASIZE(buf));
+//  gst_buffer_unref(buf);
+  samples = (gint16 *)GST_BUFFER_DATA(buf);
+
+//  return;
+//  spec_base = (gint) (log(samplecount) / log(2));
+//  if (spec_base > 10) spec_base = 10;
+//  spec_len = (gint) pow(2, spec_base);
+  spec_base = 8;
+  spec_len = 1024;
+
+  im = g_malloc(spec_len * sizeof(gint16));
+  g_return_if_fail(im != NULL);
+  loud = g_malloc(spec_len * sizeof(gint16));
+  g_return_if_fail(loud != NULL);
+
+  memset(im,0,spec_len * sizeof(gint16));
+  //if (spectrum->meta->channels == 2) {
+    re = g_malloc(spec_len * sizeof(gint16));
+    for (i=0;i<spec_len;i++)
+      re[i] = (samples[(i*2)] + samples[(i*2)+1]) >> 1;
+  //} else
+  //  re = samples;
+  gst_spectrum_window(re,spec_len);
+  gst_spectrum_fix_fft(re,im,spec_base,FALSE);
+  gst_spectrum_fix_loud(loud,re,im,spec_len,0);
+  if (re != samples) g_free(re);
+  g_free(im);
+  step = spec_len / (spectrum->width*2);
+  spect = (guchar *)g_malloc(spectrum->width);
+  for (i=0,pos=0;i<spectrum->width;i++,pos += step) {
+    if (loud[pos] > -60)
+      spect[i] = (loud[pos] + 60) / 2;
+    else
+      spect[i] = 0;
+//    if (spect[i] > 15);
+//      spect[i] = 15;
+  }
+  g_free(loud);
+  gst_buffer_unref(buf);
+//  g_free(samples);
+
+  newbuf = gst_buffer_new();
+  g_return_if_fail(newbuf != NULL);
+  GST_BUFFER_DATA(newbuf) = spect;
+  GST_BUFFER_SIZE(newbuf) = spectrum->width;
+
+  gst_pad_push(spectrum->srcpad,newbuf);
+}
+
+static gboolean
+plugin_init (GModule *module, GstPlugin *plugin)
+{
+  GstElementFactory *factory;
+
+  /* create an elementfactory for the spectrum element */
+  factory = gst_elementfactory_new ("spectrum",GST_TYPE_SPECTRUM,
+                                    &gst_spectrum_details);
+  g_return_val_if_fail (factory != NULL, FALSE);
+
+  gst_plugin_add_feature (plugin, GST_PLUGIN_FEATURE (factory));
+
+  return TRUE;
+}
+
+GstPluginDesc plugin_desc = {
+  GST_VERSION_MAJOR,
+  GST_VERSION_MINOR,
+  "spectrum",
+  plugin_init
+};
diff --git a/gst/spectrum/gstspectrum.h b/gst/spectrum/gstspectrum.h
new file mode 100644
index 00000000..f7a395ec
--- /dev/null
+++ b/gst/spectrum/gstspectrum.h
@@ -0,0 +1,67 @@
+/* Gnome-Streamer
+ * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+
+#ifndef __GST_SPECTRUM_H__
+#define __GST_SPECTRUM_H__
+
+
+#include <gst/gst.h>
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+
+#define GST_TYPE_SPECTRUM \
+  (gst_spectrum_get_type())
+#define GST_SPECTRUM(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_SPECTRUM,GstSpectrum))
+#define GST_SPECTRUM_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_SPECTRUM,GstSpectrum))
+#define GST_IS_SPECTRUM(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_SPECTRUM))
+#define GST_IS_SPECTRUM_CLASS(obj) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_SPECTRUM))
+
+typedef struct _GstSpectrum GstSpectrum;
+typedef struct _GstSpectrumClass GstSpectrumClass;
+
+struct _GstSpectrum {
+  GstElement element;
+
+  GstPad *sinkpad,*srcpad;
+
+  gint width;
+};
+
+struct _GstSpectrumClass {
+  GstElementClass parent_class;
+};
+
+GType gst_spectrum_get_type(void);
+
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+
+#endif /* __GST_SPECTRUM_H__ */