From 309d16a4a0485554645bfb3e5f9d476e793ce731 Mon Sep 17 00:00:00 2001 From: Måns Rullgård Date: Mon, 12 Apr 2010 20:45:25 +0000 Subject: DCA: break out lfe_interpolation_fir() inner loops to a function This enables SIMD optimisations of this function. Originally committed as revision 22861 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/dcadsp.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 libavcodec/dcadsp.c (limited to 'libavcodec/dcadsp.c') diff --git a/libavcodec/dcadsp.c b/libavcodec/dcadsp.c new file mode 100644 index 0000000000..fcd3b85451 --- /dev/null +++ b/libavcodec/dcadsp.c @@ -0,0 +1,49 @@ +/* + * Copyright (c) 2004 Gildas Bazin + * Copyright (c) 2010 Mans Rullgard + * + * 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 + */ + +#include "dcadsp.h" + +static void dca_lfe_fir_c(float *out, const float *in, const float *coefs, + int decifactor, float scale, float bias) +{ + float *out2 = out + decifactor; + const float *cf0 = coefs; + const float *cf1 = coefs + 256; + int j, k; + + /* One decimated sample generates 2*decifactor interpolated ones */ + for (k = 0; k < decifactor; k++) { + float v0 = 0.0; + float v1 = 0.0; + for (j = 0; j < 256 / decifactor; j++) { + float s = in[-j]; + v0 += s * *cf0++; + v1 += s * *--cf1; + } + *out++ = (v0 * scale) + bias; + *out2++ = (v1 * scale) + bias; + } +} + +void ff_dcadsp_init(DCADSPContext *s) +{ + s->lfe_fir = dca_lfe_fir_c; +} -- cgit v1.2.3