ref: 174483574aec53d3a45379fdc0b4c1907d7c7ae1
dir: /src/libflac/fixed.c/
/* libFLAC - Free Lossless Audio Codec library * Copyright (C) 2000-2009 Josh Coalson * Copyright (C) 2011-2016 Xiph.Org Foundation * * 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 <string.h> #include "share/compat.h" #include "private/bitmath.h" #include "private/fixed.h" #include "private/macros.h" #ifdef local_abs #undef local_abs #endif #define local_abs(x) ((uint32_t)((x)<0? -(x) : (x))) void FLAC__fixed_compute_residual(const FLAC__int32 data[], uint32_t data_len, uint32_t order, FLAC__int32 residual[]) { const int idata_len = (int)data_len; int i; switch(order) { case 0: memcpy(residual, data, sizeof(residual[0])*data_len); break; case 1: for(i = 0; i < idata_len; i++) residual[i] = data[i] - data[i-1]; break; case 2: for(i = 0; i < idata_len; i++) residual[i] = data[i] - 2*data[i-1] + data[i-2]; break; case 3: for(i = 0; i < idata_len; i++) residual[i] = data[i] - 3*data[i-1] + 3*data[i-2] - data[i-3]; break; case 4: for(i = 0; i < idata_len; i++) residual[i] = data[i] - 4*data[i-1] + 6*data[i-2] - 4*data[i-3] + data[i-4]; break; default: break; } } void FLAC__fixed_restore_signal(const FLAC__int32 residual[], uint32_t data_len, uint32_t order, FLAC__int32 data[]) { int i, idata_len = (int)data_len; switch(order) { case 0: memcpy(data, residual, sizeof(residual[0])*data_len); break; case 1: for(i = 0; i < idata_len; i++) data[i] = residual[i] + data[i-1]; break; case 2: for(i = 0; i < idata_len; i++) data[i] = residual[i] + 2*data[i-1] - data[i-2]; break; case 3: for(i = 0; i < idata_len; i++) data[i] = residual[i] + 3*data[i-1] - 3*data[i-2] + data[i-3]; break; case 4: for(i = 0; i < idata_len; i++) data[i] = residual[i] + 4*data[i-1] - 6*data[i-2] + 4*data[i-3] - data[i-4]; break; default: break; } }