From b4c13d9c8584ddf2f0b5d08fd6851cbdfd59ab4d Mon Sep 17 00:00:00 2001 From: Josh Coalson Date: Tue, 25 Apr 2006 06:35:03 +0000 Subject: [PATCH] *** empty log message *** --- src/libFLAC/include/private/window.h | 71 ++++++++++++ src/libFLAC/window.c | 216 +++++++++++++++++++++++++++++++++++ 2 files changed, 287 insertions(+) create mode 100644 src/libFLAC/include/private/window.h create mode 100644 src/libFLAC/window.c diff --git a/src/libFLAC/include/private/window.h b/src/libFLAC/include/private/window.h new file mode 100644 index 0000000..7b801df --- /dev/null +++ b/src/libFLAC/include/private/window.h @@ -0,0 +1,71 @@ +/* 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 +#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 diff --git a/src/libFLAC/window.c b/src/libFLAC/window.c new file mode 100644 index 0000000..33c319f --- /dev/null +++ b/src/libFLAC/window.c @@ -0,0 +1,216 @@ +/* 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 +#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 */ -- 2.7.4