1 | /* |
2 | Copyright 2018 Google Inc. All Rights Reserved. |
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 | // Prevent Visual Studio from complaining about std::copy_n. |
18 | #if defined(_WIN32) |
19 | #define _SCL_SECURE_NO_WARNINGS |
20 | #endif |
21 | |
22 | #include "utils/buffer_unpartitioner.h" |
23 | |
24 | #include "utils/planar_interleaved_conversion.h" |
25 | #include "utils/sample_type_conversion.h" |
26 | |
27 | namespace vraudio { |
28 | |
29 | BufferUnpartitioner::BufferUnpartitioner(size_t num_channels, |
30 | size_t frames_per_buffer, |
31 | GetBufferCallback buffer_callback) |
32 | : num_channels_(num_channels), |
33 | frames_per_buffer_(frames_per_buffer), |
34 | buffer_callback_(std::move(buffer_callback)), |
35 | current_input_buffer_(nullptr), |
36 | current_buffer_read_offset_frames_(0) { |
37 | DCHECK_GT(frames_per_buffer_, 0); |
38 | DCHECK_GT(num_channels, 0); |
39 | } |
40 | |
41 | size_t BufferUnpartitioner::GetNumBuffersRequestedForNumInputFrames( |
42 | size_t num_output_frames) const { |
43 | if (num_output_frames == 0) { |
44 | return 0; |
45 | } |
46 | return (num_output_frames - GetNumFramesAvailableInBuffer() + |
47 | frames_per_buffer_ - 1) / |
48 | frames_per_buffer_; |
49 | } |
50 | |
51 | size_t BufferUnpartitioner::GetBuffer(int16* output_buffer, size_t num_channels, |
52 | size_t num_frames) { |
53 | return GetBufferTemplated<int16*>(buffer: output_buffer, num_channels, num_frames); |
54 | } |
55 | |
56 | size_t BufferUnpartitioner::GetBuffer(float* output_buffer, size_t num_channels, |
57 | size_t num_frames) { |
58 | return GetBufferTemplated<float*>(buffer: output_buffer, num_channels, num_frames); |
59 | } |
60 | |
61 | size_t BufferUnpartitioner::GetBuffer(int16** output_buffer, |
62 | size_t num_channels, size_t num_frames) { |
63 | return GetBufferTemplated<int16**>(buffer: output_buffer, num_channels, num_frames); |
64 | } |
65 | |
66 | size_t BufferUnpartitioner::GetBuffer(float** output_buffer, |
67 | size_t num_channels, size_t num_frames) { |
68 | return GetBufferTemplated<float**>(buffer: output_buffer, num_channels, num_frames); |
69 | } |
70 | |
71 | size_t BufferUnpartitioner::GetNumBufferedFrames() const { |
72 | return current_buffer_read_offset_frames_; |
73 | } |
74 | |
75 | size_t BufferUnpartitioner::GetNumFramesAvailableInBuffer() const { |
76 | if (current_input_buffer_ == nullptr) { |
77 | return 0; |
78 | } |
79 | DCHECK_GE(current_input_buffer_->num_frames(), |
80 | current_buffer_read_offset_frames_); |
81 | return current_input_buffer_->num_frames() - |
82 | current_buffer_read_offset_frames_; |
83 | } |
84 | |
85 | void BufferUnpartitioner::Clear() { |
86 | current_input_buffer_ = nullptr; |
87 | current_buffer_read_offset_frames_ = 0; |
88 | } |
89 | |
90 | template <typename BufferType> |
91 | size_t BufferUnpartitioner::GetBufferTemplated(BufferType buffer, |
92 | size_t num_channels, |
93 | size_t num_frames) { |
94 | DCHECK_EQ(num_channels, num_channels_); |
95 | |
96 | size_t num_copied_frames = 0; |
97 | while (num_copied_frames < num_frames) { |
98 | if (current_input_buffer_ == nullptr) { |
99 | current_input_buffer_ = buffer_callback_(); |
100 | if (current_input_buffer_ == nullptr) { |
101 | // No more input |AudioBuffer|s are available. |
102 | return num_copied_frames; |
103 | } |
104 | DCHECK_EQ(frames_per_buffer_, current_input_buffer_->num_frames()); |
105 | current_buffer_read_offset_frames_ = 0; |
106 | } |
107 | DCHECK_GE(frames_per_buffer_, current_buffer_read_offset_frames_); |
108 | const size_t remaining_frames_in_input_buffer = |
109 | num_frames - num_copied_frames; |
110 | DCHECK_GE(current_input_buffer_->num_frames(), |
111 | current_buffer_read_offset_frames_); |
112 | const size_t num_frames_to_process = |
113 | std::min(a: current_input_buffer_->num_frames() - |
114 | current_buffer_read_offset_frames_, |
115 | b: remaining_frames_in_input_buffer); |
116 | |
117 | FillExternalBufferWithOffset( |
118 | *current_input_buffer_, current_buffer_read_offset_frames_, buffer, |
119 | num_frames, num_channels, num_copied_frames, num_frames_to_process); |
120 | |
121 | num_copied_frames += num_frames_to_process; |
122 | |
123 | current_buffer_read_offset_frames_ += num_frames_to_process; |
124 | if (current_buffer_read_offset_frames_ == |
125 | current_input_buffer_->num_frames()) { |
126 | current_input_buffer_ = nullptr; |
127 | } |
128 | } |
129 | return num_copied_frames; |
130 | } |
131 | |
132 | } // namespace vraudio |
133 | |