*** empty log message ***

src/libFLAC/include/private/window.h

+/* libFLAC - Free Lossless Audio Codec library
+ * Copyright (C) 2006  Josh Coalson
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * - Neither the name of the Xiph.org Foundation nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef FLAC__PRIVATE__WINDOW_H
+#define FLAC__PRIVATE__WINDOW_H
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "private/float.h"
+#include "FLAC/format.h"
+
+#ifndef FLAC__INTEGER_ONLY_LIBRARY
+
+/*
+ *	FLAC__window_*()
+ *	--------------------------------------------------------------------
+ *	Calculates window coefficients according to different apodization
+ *	functions.
+ *
+ *	OUT window[0,L-1]
+ *	IN L (number of points in window)
+ */
+void FLAC__window_bartlett(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_bartlett_hann(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_blackman(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_blackman_harris_4term_92db_sidelobe(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_connes(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_flattop(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_gauss(FLAC__real *window, const FLAC__int32 L, const FLAC__real stddev); /* 0.0 < stddev <= 0.5 */
+void FLAC__window_hamming(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_hann(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_kaiser_bessel(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_nuttall(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_rectangle(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_triangle(FLAC__real *window, const FLAC__int32 L);
+void FLAC__window_tukey(FLAC__real *window, const FLAC__int32 L, const FLAC__real p);
+void FLAC__window_welch(FLAC__real *window, const FLAC__int32 L);
+
+#endif /* !defined FLAC__INTEGER_ONLY_LIBRARY */
+
+#endif

src/libFLAC/window.c

+/* libFLAC - Free Lossless Audio Codec library
+ * Copyright (C) 2006  Josh Coalson
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * - Neither the name of the Xiph.org Foundation nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <math.h>
+#include "FLAC/assert.h"
+#include "FLAC/format.h"
+#include "private/window.h"
+
+#ifndef FLAC__INTEGER_ONLY_LIBRARY
+
+
+void FLAC__window_bartlett(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	if (L & 1) {
+		for (n = 0; n <= N/2; n++)
+			window[n] = 2.0f * n / (float)N;
+		for (; n <= N; n++)
+			window[n] = 2.0f - 2.0f * n / (float)N;
+	}
+	else {
+		for (n = 0; n <= L/2-1; n++)
+			window[n] = 2.0f * n / (float)N;
+		for (; n <= N; n++)
+			window[n] = 2.0f - 2.0f * (N-n) / (float)N;
+	}
+}
+
+void FLAC__window_bartlett_hann(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	for (n = 0; n < L; n++)
+		window[n] = 0.62f - 0.48f * fabs((float)n/(float)N+0.5f) + 0.38f * cos(2.0f * M_PI * ((float)n/(float)N+0.5f));
+}
+
+void FLAC__window_blackman(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	for (n = 0; n < L; n++)
+		window[n] = 0.42f - 0.5f * cos(2.0f * M_PI * n / N) + 0.08f * cos(4.0f * M_PI * n / N);
+}
+
+/* 4-term -92dB side-lobe */
+void FLAC__window_blackman_harris_4term_92db_sidelobe(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	for (n = 0; n <= N; n++)
+		window[n] = 0.35875f - 0.48829f * cos(2.0f * M_PI * n / N) + 0.14128f * cos(4.0f * M_PI * n / N) - 0.01168f * cos(6.0f * M_PI * n / N);
+}
+
+void FLAC__window_connes(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	const double N2 = (double)N / 2.;
+	FLAC__int32 n;
+
+	for (n = 0; n <= N; n++) {
+		double k = ((double)n - N2) / N2;
+		k = 1.0f - k * k;
+		window[n] = k * k;
+	}
+}
+
+void FLAC__window_flattop(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	for (n = 0; n < L; n++)
+		window[n] = 1.0f - 1.93f * cos(2.0f * M_PI * n / N) + 1.29f * cos(4.0f * M_PI * n / N) - 0.388f * cos(6.0f * M_PI * n / N) + 0.0322f * cos(8.0f * M_PI * n / N);
+}
+
+void FLAC__window_gauss(FLAC__real *window, const FLAC__int32 L, const FLAC__real stddev)
+{
+	const FLAC__int32 N = L - 1;
+	const double N2 = (double)N / 2.;
+	FLAC__int32 n;
+
+	for (n = 0; n <= N; n++) {
+		const double k = ((double)n - N2) / (stddev * N2);
+		window[n] = exp(-0.5f * k * k);
+	}
+}
+
+void FLAC__window_hamming(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	for (n = 0; n < L; n++)
+		window[n] = 0.54f - 0.46f * cos(2.0f * M_PI * n / N);
+}
+
+void FLAC__window_hann(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	for (n = 0; n < L; n++)
+		window[n] = 0.5f - 0.5f * cos(2.0f * M_PI * n / N);
+}
+
+void FLAC__window_kaiser_bessel(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	for (n = 0; n < L; n++)
+		window[n] = 0.402f - 0.498f * cos(2.0f * M_PI * n / N) + 0.098f * cos(4.0f * M_PI * n / N) - 0.001f * cos(6.0f * M_PI * n / N);
+}
+
+void FLAC__window_nuttall(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	FLAC__int32 n;
+
+	for (n = 0; n < L; n++)
+		window[n] = 0.3635819f - 0.4891775f*cos(2.0f*M_PI*n/N) + 0.1365995f*cos(4.0f*M_PI*n/N) - 0.0106411f*cos(6.0f*M_PI*n/N);
+}
+
+void FLAC__window_rectangle(FLAC__real *window, const FLAC__int32 L)
+{
+	FLAC__int32 n;
+
+	for (n = 0; n < L; n++)
+		window[n] = 1.0f;
+}
+
+void FLAC__window_triangle(FLAC__real *window, const FLAC__int32 L)
+{
+	FLAC__int32 n;
+
+	if (L & 1) {
+		for (n = 1; n <= L+1/2; n++)
+			window[n-1] = 2.0f * n / ((float)L + 1.0f);
+		for (; n <= L; n++)
+			window[n-1] = - (float)(2 * (L - n + 1)) / ((float)L + 1.0f);
+	}
+	else {
+		for (n = 1; n <= L/2; n++)
+			window[n-1] = 2.0f * n / (float)L;
+		for (; n <= L; n++)
+			window[n-1] = ((float)(2 * (L - n)) + 1.0f) / (float)L;
+	}
+}
+
+void FLAC__window_tukey(FLAC__real *window, const FLAC__int32 L, const FLAC__real p)
+{
+	if (p <= 0.0)
+		FLAC__window_rectangle(window, L);
+	else if (p >= 1.0)
+		FLAC__window_hann(window, L);
+	else {
+		const FLAC__int32 Np = (FLAC__int32)(p / 2.0f * L) - 1;
+		FLAC__int32 n;
+		/* start with rectangle... */
+		FLAC__window_rectangle(window, L);
+		/* ...replace ends with hann */
+		if (Np > 0) {
+			for (n = 0; n <= Np; n++) {
+				window[n] = 0.5f - 0.5f * cos(M_PI * n / Np);
+				window[L-Np-1+n] = 0.5f - 0.5f * cos(M_PI * (n+Np) / Np);
+			}
+		}
+	}
+}
+
+void FLAC__window_welch(FLAC__real *window, const FLAC__int32 L)
+{
+	const FLAC__int32 N = L - 1;
+	const double N2 = (double)N / 2.;
+	FLAC__int32 n;
+
+	for (n = 0; n <= N; n++) {
+		const double k = ((double)n - N2) / N2;
+		window[n] = 1.0f - k * k;
+	}
+}
+
+#endif /* !defined FLAC__INTEGER_ONLY_LIBRARY */