1 /* 2 * Direct Stream Digital (DSD) decoder 3 * based on BSD licensed dsd2pcm by Sebastian Gesemann 4 * Copyright (c) 2009, 2011 Sebastian Gesemann. All rights reserved. 5 * Copyright (c) 2014 Peter Ross 6 * 7 * This file is part of FFmpeg. 8 * 9 * FFmpeg is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU Lesser General Public 11 * License as published by the Free Software Foundation; either 12 * version 2.1 of the License, or (at your option) any later version. 13 * 14 * FFmpeg is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * Lesser General Public License for more details. 18 * 19 * You should have received a copy of the GNU Lesser General Public 20 * License along with FFmpeg; if not, write to the Free Software 21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 22 */ 23 24 #ifndef AVCODEC_DSD_H 25 #define AVCODEC_DSD_H 26 27 #include "libavcodec/internal.h" 28 #include "libavcodec/mathops.h" 29 #include "avcodec.h" 30 31 #define HTAPS 48 /** number of FIR constants */ 32 #define FIFOSIZE 16 /** must be a power of two */ 33 #define FIFOMASK (FIFOSIZE - 1) /** bit mask for FIFO offsets */ 34 35 #if FIFOSIZE * 8 < HTAPS * 2 36 #error "FIFOSIZE too small" 37 #endif 38 39 /** 40 * Per-channel buffer 41 */ 42 typedef struct DSDContext { 43 uint8_t buf[FIFOSIZE]; 44 unsigned pos; 45 } DSDContext; 46 47 void ff_init_dsd_data(void); 48 49 void ff_dsd2pcm_translate(DSDContext* s, size_t samples, int lsbf, 50 const uint8_t *src, ptrdiff_t src_stride, 51 float *dst, ptrdiff_t dst_stride); 52 #endif /* AVCODEC_DSD_H */ 53