OpenShot Library | libopenshot  0.2.4
Brightness.cpp
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1 /**
2  * @file
3  * @brief Source file for Brightness class
4  * @author Jonathan Thomas <jonathan@openshot.org>
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 "../../include/effects/Brightness.h"
32 
33 using namespace openshot;
34 
35 /// Blank constructor, useful when using Json to load the effect properties
36 Brightness::Brightness() : brightness(0.0), contrast(3.0) {
37  // Init effect properties
38  init_effect_details();
39 }
40 
41 // Default constructor
42 Brightness::Brightness(Keyframe new_brightness, Keyframe new_contrast) : brightness(new_brightness), contrast(new_contrast)
43 {
44  // Init effect properties
45  init_effect_details();
46 }
47 
48 // Init effect settings
49 void Brightness::init_effect_details()
50 {
51  /// Initialize the values of the EffectInfo struct.
53 
54  /// Set the effect info
55  info.class_name = "Brightness";
56  info.name = "Brightness & Contrast";
57  info.description = "Adjust the brightness and contrast of the frame's image.";
58  info.has_audio = false;
59  info.has_video = true;
60 }
61 
62 // This method is required for all derived classes of EffectBase, and returns a
63 // modified openshot::Frame object
64 std::shared_ptr<Frame> Brightness::GetFrame(std::shared_ptr<Frame> frame, int64_t frame_number)
65 {
66  // Get the frame's image
67  std::shared_ptr<QImage> frame_image = frame->GetImage();
68 
69  // Get keyframe values for this frame
70  float brightness_value = brightness.GetValue(frame_number);
71  float contrast_value = contrast.GetValue(frame_number);
72 
73  // Loop through pixels
74  unsigned char *pixels = (unsigned char *) frame_image->bits();
75  for (int pixel = 0, byte_index=0; pixel < frame_image->width() * frame_image->height(); pixel++, byte_index+=4)
76  {
77  // Get the RGB values from the pixel
78  int R = pixels[byte_index];
79  int G = pixels[byte_index + 1];
80  int B = pixels[byte_index + 2];
81  int A = pixels[byte_index + 3];
82 
83  // Adjust the contrast
84  float factor = (259 * (contrast_value + 255)) / (255 * (259 - contrast_value));
85  R = constrain((factor * (R - 128)) + 128);
86  G = constrain((factor * (G - 128)) + 128);
87  B = constrain((factor * (B - 128)) + 128);
88 
89  // Adjust the brightness
90  R += (255 * brightness_value);
91  G += (255 * brightness_value);
92  B += (255 * brightness_value);
93 
94  // Constrain the value from 0 to 255
95  R = constrain(R);
96  G = constrain(G);
97  B = constrain(B);
98 
99  // Set all pixels to new value
100  pixels[byte_index] = R;
101  pixels[byte_index + 1] = G;
102  pixels[byte_index + 2] = B;
103  pixels[byte_index + 3] = A; // leave the alpha value alone
104  }
105 
106  // return the modified frame
107  return frame;
108 }
109 
110 // Generate JSON string of this object
111 std::string Brightness::Json() {
112 
113  // Return formatted string
114  return JsonValue().toStyledString();
115 }
116 
117 // Generate Json::JsonValue for this object
118 Json::Value Brightness::JsonValue() {
119 
120  // Create root json object
121  Json::Value root = EffectBase::JsonValue(); // get parent properties
122  root["type"] = info.class_name;
123  root["brightness"] = brightness.JsonValue();
124  root["contrast"] = contrast.JsonValue();
125 
126  // return JsonValue
127  return root;
128 }
129 
130 // Load JSON string into this object
131 void Brightness::SetJson(std::string value) {
132 
133  // Parse JSON string into JSON objects
134  Json::Value root;
135  Json::CharReaderBuilder rbuilder;
136  Json::CharReader* reader(rbuilder.newCharReader());
137 
138  std::string errors;
139  bool success = reader->parse( value.c_str(),
140  value.c_str() + value.size(), &root, &errors );
141  delete reader;
142 
143  if (!success)
144  // Raise exception
145  throw InvalidJSON("JSON could not be parsed (or is invalid)");
146 
147  try
148  {
149  // Set all values that match
150  SetJsonValue(root);
151  }
152  catch (const std::exception& e)
153  {
154  // Error parsing JSON (or missing keys)
155  throw InvalidJSON("JSON is invalid (missing keys or invalid data types)");
156  }
157 }
158 
159 // Load Json::JsonValue into this object
160 void Brightness::SetJsonValue(Json::Value root) {
161 
162  // Set parent data
164 
165  // Set data from Json (if key is found)
166  if (!root["brightness"].isNull())
167  brightness.SetJsonValue(root["brightness"]);
168  if (!root["contrast"].isNull())
169  contrast.SetJsonValue(root["contrast"]);
170 }
171 
172 // Get all properties for a specific frame
173 std::string Brightness::PropertiesJSON(int64_t requested_frame) {
174 
175  // Generate JSON properties list
176  Json::Value root;
177  root["id"] = add_property_json("ID", 0.0, "string", Id(), NULL, -1, -1, true, requested_frame);
178  root["position"] = add_property_json("Position", Position(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
179  root["layer"] = add_property_json("Track", Layer(), "int", "", NULL, 0, 20, false, requested_frame);
180  root["start"] = add_property_json("Start", Start(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
181  root["end"] = add_property_json("End", End(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
182  root["duration"] = add_property_json("Duration", Duration(), "float", "", NULL, 0, 30 * 60 * 60 * 48, true, requested_frame);
183 
184  // Keyframes
185  root["brightness"] = add_property_json("Brightness", brightness.GetValue(requested_frame), "float", "", &brightness, -1.0, 1.0, false, requested_frame);
186  root["contrast"] = add_property_json("Contrast", contrast.GetValue(requested_frame), "float", "", &contrast, 0.0, 100.0, false, requested_frame);
187 
188  // Return formatted string
189  return root.toStyledString();
190 }
Brightness()
Blank constructor, useful when using Json to load the effect properties.
Definition: Brightness.cpp:36
void SetJsonValue(Json::Value root)
Load Json::JsonValue into this object.
Definition: Brightness.cpp:160
Keyframe contrast
Contrast keyframe.
Definition: Brightness.h:68
float End()
Get end position (in seconds) of clip (trim end of video)
Definition: ClipBase.h:80
int Layer()
Get layer of clip on timeline (lower number is covered by higher numbers)
Definition: ClipBase.h:78
virtual Json::Value JsonValue()=0
Generate Json::JsonValue for this object.
Definition: EffectBase.cpp:84
void SetJsonValue(Json::Value root)
Load Json::JsonValue into this object.
Definition: KeyFrame.cpp:374
bool has_audio
Determines if this effect manipulates the audio of a frame.
Definition: EffectBase.h:56
std::string Id()
Get basic properties.
Definition: ClipBase.h:76
float Position()
Get position on timeline (in seconds)
Definition: ClipBase.h:77
std::string PropertiesJSON(int64_t requested_frame)
Definition: Brightness.cpp:173
virtual void SetJsonValue(Json::Value root)=0
Load Json::JsonValue into this object.
Definition: EffectBase.cpp:129
std::string class_name
The class name of the effect.
Definition: EffectBase.h:52
std::string name
The name of the effect.
Definition: EffectBase.h:53
Keyframe brightness
Brightness keyframe. A constant value here will prevent animation.
Definition: Brightness.h:67
void SetJson(std::string value)
Load JSON string into this object.
Definition: Brightness.cpp:131
Json::Value add_property_json(std::string name, float value, std::string type, std::string memo, Keyframe *keyframe, float min_value, float max_value, bool readonly, int64_t requested_frame)
Generate JSON for a property.
Definition: ClipBase.cpp:68
std::shared_ptr< Frame > GetFrame(std::shared_ptr< Frame > frame, int64_t frame_number)
This method is required for all derived classes of EffectBase, and returns a modified openshot::Frame...
Definition: Brightness.cpp:64
This namespace is the default namespace for all code in the openshot library.
Json::Value JsonValue() const
Generate Json::JsonValue for this object.
Definition: KeyFrame.cpp:329
std::string description
The description of this effect and what it does.
Definition: EffectBase.h:54
bool has_video
Determines if this effect manipulates the image of a frame.
Definition: EffectBase.h:55
Exception for invalid JSON.
Definition: Exceptions.h:205
double GetValue(int64_t index) const
Get the value at a specific index.
Definition: KeyFrame.cpp:262
int constrain(int color_value)
Constrain a color value from 0 to 255.
Definition: EffectBase.cpp:65
std::string Json()
Get and Set JSON methods.
Definition: Brightness.cpp:111
A Keyframe is a collection of Point instances, which is used to vary a number or property over time...
Definition: KeyFrame.h:64
float Duration()
Get the length of this clip (in seconds)
Definition: ClipBase.h:81
Json::Value JsonValue()
Generate Json::JsonValue for this object.
Definition: Brightness.cpp:118
float Start()
Get start position (in seconds) of clip (trim start of video)
Definition: ClipBase.h:79
EffectInfoStruct info
Information about the current effect.
Definition: EffectBase.h:73