primitives.c revision 7a0bacaf9634d6bf0abbea9608fb15e94a675358
1/* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include <audio_utils/primitives.h> 18 19void ditherAndClamp(int32_t* out, int32_t const *sums, size_t c) 20{ 21 size_t i; 22 for (i=0 ; i<c ; i++) { 23 int32_t l = *sums++; 24 int32_t r = *sums++; 25 int32_t nl = l >> 12; 26 int32_t nr = r >> 12; 27 l = clamp16(nl); 28 r = clamp16(nr); 29 *out++ = (r<<16) | (l & 0xFFFF); 30 } 31} 32 33void memcpy_to_i16_from_u8(int16_t *dst, const uint8_t *src, size_t count) 34{ 35 dst += count; 36 src += count; 37 while (count--) { 38 *--dst = (int16_t)(*--src - 0x80) << 8; 39 } 40} 41 42void downmix_to_mono_i16_from_stereo_i16(int16_t *dst, const int16_t *src, size_t count) 43{ 44 while (count--) { 45 *dst++ = (int16_t)(((int32_t)src[0] + (int32_t)src[1]) >> 1); 46 src += 2; 47 } 48} 49 50void upmix_to_stereo_i16_from_mono_i16(int16_t *dst, const int16_t *src, size_t count) 51{ 52 while (count--) { 53 int32_t temp = *src++; 54 dst[0] = temp; 55 dst[1] = temp; 56 dst += 2; 57 } 58} 59