1 /**
2 * @file
3 * @brief Source file for Delay audio effect class
4 * @author
5 *
6 * @ref License
7 */
8
9 /* LICENSE
10 *
11 * Copyright (c) 2008-2019 OpenShot Studios, LLC
12 * <http://www.openshotstudios.com/>. This file is part of
13 * OpenShot Library (libopenshot), an open-source project dedicated to
14 * delivering high quality video editing and animation solutions to the
15 * world. For more information visit <http://www.openshot.org/>.
16 *
17 * OpenShot Library (libopenshot) is free software: you can redistribute it
18 * and/or modify it under the terms of the GNU Lesser General Public License
19 * as published by the Free Software Foundation, either version 3 of the
20 * License, or (at your option) any later version.
21 *
22 * OpenShot Library (libopenshot) is distributed in the hope that it will be
23 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU Lesser General Public License for more details.
26 *
27 * You should have received a copy of the GNU Lesser General Public License
28 * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
29 */
30
31 #include "Delay.h"
32 #include "Exceptions.h"
33
34 using namespace openshot;
35
36 /// Blank constructor, useful when using Json to load the effect properties
Delay()37 Delay::Delay() : delay_time(1) {
38 // Init effect properties
39 init_effect_details();
40 }
41
42 // Default constructor
Delay(Keyframe new_delay_time)43 Delay::Delay(Keyframe new_delay_time) : delay_time(new_delay_time)
44 {
45 // Init effect properties
46 init_effect_details();
47 }
48
49 // Init effect settings
init_effect_details()50 void Delay::init_effect_details()
51 {
52 /// Initialize the values of the EffectInfo struct.
53 InitEffectInfo();
54
55 /// Set the effect info
56 info.class_name = "Delay";
57 info.name = "Delay";
58 info.description = "Adjust the synchronism between the audio and video track.";
59 info.has_audio = true;
60 info.has_video = false;
61 initialized = false;
62 }
63
setup(std::shared_ptr<openshot::Frame> frame)64 void Delay::setup(std::shared_ptr<openshot::Frame> frame)
65 {
66 if (!initialized)
67 {
68 const float max_delay_time = 5;
69 delay_buffer_samples = (int)(max_delay_time * (float)frame->SampleRate()) + 1;
70
71 if (delay_buffer_samples < 1)
72 delay_buffer_samples = 1;
73
74 delay_buffer_channels = frame->audio->getNumChannels();
75 delay_buffer.setSize(delay_buffer_channels, delay_buffer_samples);
76 delay_buffer.clear();
77 delay_write_position = 0;
78 initialized = true;
79 }
80 }
81
82 // This method is required for all derived classes of EffectBase, and returns a
83 // modified openshot::Frame object
GetFrame(std::shared_ptr<openshot::Frame> frame,int64_t frame_number)84 std::shared_ptr<openshot::Frame> Delay::GetFrame(std::shared_ptr<openshot::Frame> frame, int64_t frame_number)
85 {
86 const float delay_time_value = (float)delay_time.GetValue(frame_number)*(float)frame->SampleRate();
87 int local_write_position;
88
89 setup(frame);
90
91 for (int channel = 0; channel < frame->audio->getNumChannels(); channel++)
92 {
93 float *channel_data = frame->audio->getWritePointer(channel);
94 float *delay_data = delay_buffer.getWritePointer(channel);
95 local_write_position = delay_write_position;
96
97 for (auto sample = 0; sample < frame->audio->getNumSamples(); ++sample)
98 {
99 const float in = (float)(channel_data[sample]);
100 float out = 0.0f;
101
102 float read_position = fmodf((float)local_write_position - delay_time_value + (float)delay_buffer_samples, delay_buffer_samples);
103 int local_read_position = floorf(read_position);
104
105 if (local_read_position != local_write_position)
106 {
107 float fraction = read_position - (float)local_read_position;
108 float delayed1 = delay_data[(local_read_position + 0)];
109 float delayed2 = delay_data[(local_read_position + 1) % delay_buffer_samples];
110 out = (float)(delayed1 + fraction * (delayed2 - delayed1));
111
112 channel_data[sample] = in + (out - in);
113 delay_data[local_write_position] = in;
114 }
115
116 if (++local_write_position >= delay_buffer_samples)
117 local_write_position -= delay_buffer_samples;
118 }
119 }
120
121 delay_write_position = local_write_position;
122
123 // return the modified frame
124 return frame;
125 }
126
127 // Generate JSON string of this object
Json() const128 std::string Delay::Json() const {
129
130 // Return formatted string
131 return JsonValue().toStyledString();
132 }
133
134 // Generate Json::Value for this object
JsonValue() const135 Json::Value Delay::JsonValue() const {
136
137 // Create root json object
138 Json::Value root = EffectBase::JsonValue(); // get parent properties
139 root["type"] = info.class_name;
140 root["delay_time"] = delay_time.JsonValue();
141
142 // return JsonValue
143 return root;
144 }
145
146 // Load JSON string into this object
SetJson(const std::string value)147 void Delay::SetJson(const std::string value) {
148
149 // Parse JSON string into JSON objects
150 try
151 {
152 const Json::Value root = openshot::stringToJson(value);
153 // Set all values that match
154 SetJsonValue(root);
155 }
156 catch (const std::exception& e)
157 {
158 // Error parsing JSON (or missing keys)
159 throw InvalidJSON("JSON is invalid (missing keys or invalid data types)");
160 }
161 }
162
163 // Load Json::Value into this object
SetJsonValue(const Json::Value root)164 void Delay::SetJsonValue(const Json::Value root) {
165
166 // Set parent data
167 EffectBase::SetJsonValue(root);
168
169 // Set data from Json (if key is found)
170 if (!root["delay_time"].isNull())
171 delay_time.SetJsonValue(root["delay_time"]);
172 }
173
174 // Get all properties for a specific frame
PropertiesJSON(int64_t requested_frame) const175 std::string Delay::PropertiesJSON(int64_t requested_frame) const {
176
177 // Generate JSON properties list
178 Json::Value root;
179 root["id"] = add_property_json("ID", 0.0, "string", Id(), NULL, -1, -1, true, requested_frame);
180 root["layer"] = add_property_json("Track", Layer(), "int", "", NULL, 0, 20, false, requested_frame);
181 root["start"] = add_property_json("Start", Start(), "float", "", NULL, 0, 1000 * 60 * 30, false, requested_frame);
182 root["end"] = add_property_json("End", End(), "float", "", NULL, 0, 1000 * 60 * 30, false, requested_frame);
183 root["duration"] = add_property_json("Duration", Duration(), "float", "", NULL, 0, 1000 * 60 * 30, true, requested_frame);
184
185 // Keyframes
186 root["delay_time"] = add_property_json("Delay Time", delay_time.GetValue(requested_frame), "float", "", &delay_time, 0, 5, false, requested_frame);
187
188 // Return formatted string
189 return root.toStyledString();
190 }
191