OpenShot Library | libopenshot 0.2.7
Delay.cpp
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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
34using namespace openshot;
35
36/// Blank constructor, useful when using Json to load the effect properties
37Delay::Delay() : delay_time(1) {
38 // Init effect properties
39 init_effect_details();
40}
41
42// Default constructor
43Delay::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
50void Delay::init_effect_details()
51{
52 /// Initialize the values of the EffectInfo struct.
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
64void 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
73
74 delay_buffer_channels = frame->audio->getNumChannels();
76 delay_buffer.clear();
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
84std::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
128std::string Delay::Json() const {
129
130 // Return formatted string
131 return JsonValue().toStyledString();
132}
133
134// Generate Json::Value for this object
135Json::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
147void 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
164void Delay::SetJsonValue(const Json::Value root) {
165
166 // Set parent data
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
175std::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}
Header file for Delay audio effect class.
Header file for all Exception classes.
float End() const
Get end position (in seconds) of clip (trim end of video)
Definition: ClipBase.h:111
float Start() const
Get start position (in seconds) of clip (trim start of video)
Definition: ClipBase.h:110
float Duration() const
Get the length of this clip (in seconds)
Definition: ClipBase.h:112
std::string Id() const
Get the Id of this clip object.
Definition: ClipBase.h:107
int Layer() const
Get layer of clip on timeline (lower number is covered by higher numbers)
Definition: ClipBase.h:109
Json::Value add_property_json(std::string name, float value, std::string type, std::string memo, const Keyframe *keyframe, float min_value, float max_value, bool readonly, int64_t requested_frame) const
Generate JSON for a property.
Definition: ClipBase.cpp:68
juce::AudioSampleBuffer delay_buffer
Definition: Delay.h:62
void SetJsonValue(const Json::Value root) override
Load Json::Value into this object.
Definition: Delay.cpp:164
Keyframe delay_time
Definition: Delay.h:60
std::shared_ptr< openshot::Frame > GetFrame(int64_t frame_number) override
This method is required for all derived classes of ClipBase, and returns a new openshot::Frame object...
Definition: Delay.h:80
Delay()
Blank constructor, useful when using Json to load the effect properties.
Definition: Delay.cpp:37
void SetJson(const std::string value) override
Load JSON string into this object.
Definition: Delay.cpp:147
Json::Value JsonValue() const override
Generate Json::Value for this object.
Definition: Delay.cpp:135
std::string Json() const override
Generate JSON string of this object.
Definition: Delay.cpp:128
int delay_write_position
Definition: Delay.h:65
int delay_buffer_samples
Definition: Delay.h:63
std::string PropertiesJSON(int64_t requested_frame) const override
Definition: Delay.cpp:175
bool initialized
Definition: Delay.h:66
int delay_buffer_channels
Definition: Delay.h:64
void setup(std::shared_ptr< openshot::Frame > frame)
Definition: Delay.cpp:64
virtual Json::Value JsonValue() const
Generate Json::Value for this object.
Definition: EffectBase.cpp:92
virtual void SetJsonValue(const Json::Value root)
Load Json::Value into this object.
Definition: EffectBase.cpp:127
EffectInfoStruct info
Information about the current effect.
Definition: EffectBase.h:87
Exception for invalid JSON.
Definition: Exceptions.h:206
A Keyframe is a collection of Point instances, which is used to vary a number or property over time.
Definition: KeyFrame.h:72
void SetJsonValue(const Json::Value root)
Load Json::Value into this object.
Definition: KeyFrame.cpp:368
double GetValue(int64_t index) const
Get the value at a specific index.
Definition: KeyFrame.cpp:268
Json::Value JsonValue() const
Generate Json::Value for this object.
Definition: KeyFrame.cpp:335
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:47
const Json::Value stringToJson(const std::string value)
Definition: Json.cpp:34
bool has_video
Determines if this effect manipulates the image of a frame.
Definition: EffectBase.h:58
bool has_audio
Determines if this effect manipulates the audio of a frame.
Definition: EffectBase.h:59
std::string class_name
The class name of the effect.
Definition: EffectBase.h:54
std::string name
The name of the effect.
Definition: EffectBase.h:55
std::string description
The description of this effect and what it does.
Definition: EffectBase.h:56