1 /* 2 * Copyright (c) 2013 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #include "webrtc/modules/audio_coding/neteq/tools/audio_loop.h" 12 13 #include <assert.h> 14 #include <stdio.h> 15 #include <string.h> 16 17 namespace webrtc { 18 namespace test { 19 20 bool AudioLoop::Init(const std::string file_name, 21 size_t max_loop_length_samples, 22 size_t block_length_samples) { 23 FILE* fp = fopen(file_name.c_str(), "rb"); 24 if (!fp) return false; 25 26 audio_array_.reset(new int16_t[max_loop_length_samples + 27 block_length_samples]); 28 size_t samples_read = fread(audio_array_.get(), sizeof(int16_t), 29 max_loop_length_samples, fp); 30 fclose(fp); 31 32 // Block length must be shorter than the loop length. 33 if (block_length_samples > samples_read) return false; 34 35 // Add an extra block length of samples to the end of the array, starting 36 // over again from the beginning of the array. This is done to simplify 37 // the reading process when reading over the end of the loop. 38 memcpy(&audio_array_[samples_read], audio_array_.get(), 39 block_length_samples * sizeof(int16_t)); 40 41 loop_length_samples_ = samples_read; 42 block_length_samples_ = block_length_samples; 43 return true; 44 } 45 46 const int16_t* AudioLoop::GetNextBlock() { 47 // Check that the AudioLoop is initialized. 48 if (block_length_samples_ == 0) return NULL; 49 50 const int16_t* output_ptr = &audio_array_[next_index_]; 51 next_index_ = (next_index_ + block_length_samples_) % loop_length_samples_; 52 return output_ptr; 53 } 54 55 56 } // namespace test 57 } // namespace webrtc 58
