diff --git a/libavcodec/dsd.c b/libavcodec/dsd.c index 95aab61ea4..c18e20436a 100644 --- a/libavcodec/dsd.c +++ b/libavcodec/dsd.c @@ -25,9 +25,51 @@ #include "libavcodec/internal.h" #include "libavcodec/mathops.h" #include "avcodec.h" -#include "dsd_tablegen.h" #include "dsd.h" +#define CTABLES ((HTAPS + 7) / 8) /** number of "8 MACs" lookup tables */ + +/* + * Properties of this 96-tap lowpass filter when applied on a signal + * with sampling rate of 44100*64 Hz: + * + * () has a delay of 17 microseconds. + * + * () flat response up to 48 kHz + * + * () if you downsample afterwards by a factor of 8, the + * spectrum below 70 kHz is practically alias-free. + * + * () stopband rejection is about 160 dB + * + * The coefficient tables ("ctables") take only 6 Kibi Bytes and + * should fit into a modern processor's fast cache. + */ + +/** + * The 2nd half (48 coeffs) of a 96-tap symmetric lowpass filter + */ +static const double htaps[HTAPS] = { + 0.09950731974056658, 0.09562845727714668, 0.08819647126516944, + 0.07782552527068175, 0.06534876523171299, 0.05172629311427257, + 0.0379429484910187, 0.02490921351762261, 0.0133774746265897, + 0.003883043418804416, -0.003284703416210726, -0.008080250212687497, + -0.01067241812471033, -0.01139427235000863, -0.0106813877974587, + -0.009007905078766049, -0.006828859761015335, -0.004535184322001496, + -0.002425035959059578, -0.0006922187080790708, 0.0005700762133516592, + 0.001353838005269448, 0.001713709169690937, 0.001742046839472948, + 0.001545601648013235, 0.001226696225277855, 0.0008704322683580222, + 0.0005381636200535649, 0.000266446345425276, 7.002968738383528e-05, + -5.279407053811266e-05, -0.0001140625650874684, -0.0001304796361231895, + -0.0001189970287491285, -9.396247155265073e-05, -6.577634378272832e-05, + -4.07492895872535e-05, -2.17407957554587e-05, -9.163058931391722e-06, + -2.017460145032201e-06, 1.249721855219005e-06, 2.166655190537392e-06, + 1.930520892991082e-06, 1.319400334374195e-06, 7.410039764949091e-07, + 3.423230509967409e-07, 1.244182214744588e-07, 3.130441005359396e-08 +}; + +static float ctables[CTABLES][256]; + static av_cold void dsd_ctables_tableinit(void) { int t, e, m, sign; diff --git a/libavcodec/dsd_tablegen.h b/libavcodec/dsd_tablegen.h deleted file mode 100644 index e5da86a1dc..0000000000 --- a/libavcodec/dsd_tablegen.h +++ /dev/null @@ -1,75 +0,0 @@ -/* - * Header file for hardcoded DSD tables - * based on BSD licensed dsd2pcm by Sebastian Gesemann - * Copyright (c) 2009, 2011 Sebastian Gesemann. All rights reserved. - * - * This file is part of FFmpeg. - * - * FFmpeg is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; either - * version 2.1 of the License, or (at your option) any later version. - * - * FFmpeg 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 - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with FFmpeg; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#ifndef AVCODEC_DSD_TABLEGEN_H -#define AVCODEC_DSD_TABLEGEN_H - -#include -#include "libavutil/attributes.h" -#include "dsd.h" - -#define HTAPS 48 /** number of FIR constants */ -#define CTABLES ((HTAPS + 7) / 8) /** number of "8 MACs" lookup tables */ - -#include "libavutil/common.h" - -/* - * Properties of this 96-tap lowpass filter when applied on a signal - * with sampling rate of 44100*64 Hz: - * - * () has a delay of 17 microseconds. - * - * () flat response up to 48 kHz - * - * () if you downsample afterwards by a factor of 8, the - * spectrum below 70 kHz is practically alias-free. - * - * () stopband rejection is about 160 dB - * - * The coefficient tables ("ctables") take only 6 Kibi Bytes and - * should fit into a modern processor's fast cache. - */ - -/** - * The 2nd half (48 coeffs) of a 96-tap symmetric lowpass filter - */ -static const double htaps[HTAPS] = { - 0.09950731974056658, 0.09562845727714668, 0.08819647126516944, - 0.07782552527068175, 0.06534876523171299, 0.05172629311427257, - 0.0379429484910187, 0.02490921351762261, 0.0133774746265897, - 0.003883043418804416, -0.003284703416210726, -0.008080250212687497, - -0.01067241812471033, -0.01139427235000863, -0.0106813877974587, - -0.009007905078766049, -0.006828859761015335, -0.004535184322001496, - -0.002425035959059578, -0.0006922187080790708, 0.0005700762133516592, - 0.001353838005269448, 0.001713709169690937, 0.001742046839472948, - 0.001545601648013235, 0.001226696225277855, 0.0008704322683580222, - 0.0005381636200535649, 0.000266446345425276, 7.002968738383528e-05, - -5.279407053811266e-05, -0.0001140625650874684, -0.0001304796361231895, - -0.0001189970287491285, -9.396247155265073e-05, -6.577634378272832e-05, - -4.07492895872535e-05, -2.17407957554587e-05, -9.163058931391722e-06, - -2.017460145032201e-06, 1.249721855219005e-06, 2.166655190537392e-06, - 1.930520892991082e-06, 1.319400334374195e-06, 7.410039764949091e-07, - 3.423230509967409e-07, 1.244182214744588e-07, 3.130441005359396e-08 -}; - -static float ctables[CTABLES][256]; -#endif /* AVCODEC_DSD_TABLEGEN_H */