OpenShot Library | libopenshot  0.2.6
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 
34 using namespace openshot;
35 
36 /// Blank constructor, useful when using Json to load the effect properties
37 Delay::Delay() : delay_time(1) {
38  // Init effect properties
39  init_effect_details();
40 }
41 
42 // Default constructor
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
50 void 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 
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)
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
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
128 std::string Delay::Json() const {
129 
130  // Return formatted string
131  return JsonValue().toStyledString();
132 }
133 
134 // Generate Json::Value for this object
135 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
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
164 void 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
175 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 }
void SetJson(const std::string value) override
Load JSON string into this object.
Definition: Delay.cpp:147
int delay_buffer_samples
Definition: Delay.h:63
std::string Json() const override
Generate JSON string of this object.
Definition: Delay.cpp:128
std::string Id() const
Get the Id of this clip object.
Definition: ClipBase.h:107
float Start() const
Get start position (in seconds) of clip (trim start of video)
Definition: ClipBase.h:110
virtual void SetJsonValue(const Json::Value root)
Load Json::Value into this object.
Definition: EffectBase.cpp:127
std::string PropertiesJSON(int64_t requested_frame) const override
Definition: Delay.cpp:175
const Json::Value stringToJson(const std::string value)
Definition: Json.cpp:34
virtual Json::Value JsonValue() const
Generate Json::Value for this object.
Definition: EffectBase.cpp:92
Delay()
Blank constructor, useful when using Json to load the effect properties.
Definition: Delay.cpp:37
Json::Value JsonValue() const override
Generate Json::Value for this object.
Definition: Delay.cpp:135
bool has_audio
Determines if this effect manipulates the audio of a frame.
Definition: EffectBase.h:59
Header file for all Exception classes.
juce::AudioSampleBuffer delay_buffer
Definition: Delay.h:62
void setup(std::shared_ptr< openshot::Frame > frame)
Definition: Delay.cpp:64
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
bool initialized
Definition: Delay.h:66
Keyframe delay_time
Definition: Delay.h:60
int delay_buffer_channels
Definition: Delay.h:64
Header file for Delay audio effect class.
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
int delay_write_position
Definition: Delay.h:65
float Duration() const
Get the length of this clip (in seconds)
Definition: ClipBase.h:112
void SetJsonValue(const Json::Value root)
Load Json::Value into this object.
Definition: KeyFrame.cpp:368
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:46
Json::Value JsonValue() const
Generate Json::Value for this object.
Definition: KeyFrame.cpp:335
std::string description
The description of this effect and what it does.
Definition: EffectBase.h:56
bool has_video
Determines if this effect manipulates the image of a frame.
Definition: EffectBase.h:58
Exception for invalid JSON.
Definition: Exceptions.h:205
double GetValue(int64_t index) const
Get the value at a specific index.
Definition: KeyFrame.cpp:268
float End() const
Get end position (in seconds) of clip (trim end of video)
Definition: ClipBase.h:111
A Keyframe is a collection of Point instances, which is used to vary a number or property over time...
Definition: KeyFrame.h:72
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
int Layer() const
Get layer of clip on timeline (lower number is covered by higher numbers)
Definition: ClipBase.h:109
EffectInfoStruct info
Information about the current effect.
Definition: EffectBase.h:87
void SetJsonValue(const Json::Value root) override
Load Json::Value into this object.
Definition: Delay.cpp:164