OpenShot Library | libopenshot  0.2.7
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 "Brightness.h"
32 #include "Exceptions.h"
33 
34 using namespace openshot;
35 
36 /// Blank constructor, useful when using Json to load the effect properties
37 Brightness::Brightness() : brightness(0.0), contrast(3.0) {
38  // Init effect properties
39  init_effect_details();
40 }
41 
42 // Default constructor
43 Brightness::Brightness(Keyframe new_brightness, Keyframe new_contrast) : brightness(new_brightness), contrast(new_contrast)
44 {
45  // Init effect properties
46  init_effect_details();
47 }
48 
49 // Init effect settings
50 void Brightness::init_effect_details()
51 {
52  /// Initialize the values of the EffectInfo struct.
54 
55  /// Set the effect info
56  info.class_name = "Brightness";
57  info.name = "Brightness & Contrast";
58  info.description = "Adjust the brightness and contrast of the frame's image.";
59  info.has_audio = false;
60  info.has_video = true;
61 }
62 
63 // This method is required for all derived classes of EffectBase, and returns a
64 // modified openshot::Frame object
65 std::shared_ptr<openshot::Frame> Brightness::GetFrame(std::shared_ptr<openshot::Frame> frame, int64_t frame_number)
66 {
67  // Get the frame's image
68  std::shared_ptr<QImage> frame_image = frame->GetImage();
69 
70  // Get keyframe values for this frame
71  float brightness_value = brightness.GetValue(frame_number);
72  float contrast_value = contrast.GetValue(frame_number);
73 
74  // Loop through pixels
75  unsigned char *pixels = (unsigned char *) frame_image->bits();
76  int pixel_count = frame_image->width() * frame_image->height();
77 
78  #pragma omp parallel for
79  for (int pixel = 0; pixel < pixel_count; ++pixel)
80  {
81  // Compute contrast adjustment factor
82  float factor = (259 * (contrast_value + 255)) / (255 * (259 - contrast_value));
83 
84  // Get RGB pixels from image and apply constrained contrast adjustment
85  int R = constrain((factor * (pixels[pixel * 4] - 128)) + 128);
86  int G = constrain((factor * (pixels[pixel * 4 + 1] - 128)) + 128);
87  int B = constrain((factor * (pixels[pixel * 4 + 2] - 128)) + 128);
88  // (Don't modify Alpha value)
89 
90  // Adjust brightness and write constrained values back to image
91  pixels[pixel * 4] = constrain(R + (255 * brightness_value));
92  pixels[pixel * 4 + 1] = constrain(G + (255 * brightness_value));
93  pixels[pixel * 4 + 2] = constrain(B + (255 * brightness_value));
94  }
95 
96  // return the modified frame
97  return frame;
98 }
99 
100 // Generate JSON string of this object
101 std::string Brightness::Json() const {
102 
103  // Return formatted string
104  return JsonValue().toStyledString();
105 }
106 
107 // Generate Json::Value for this object
108 Json::Value Brightness::JsonValue() const {
109 
110  // Create root json object
111  Json::Value root = EffectBase::JsonValue(); // get parent properties
112  root["type"] = info.class_name;
113  root["brightness"] = brightness.JsonValue();
114  root["contrast"] = contrast.JsonValue();
115 
116  // return JsonValue
117  return root;
118 }
119 
120 // Load JSON string into this object
121 void Brightness::SetJson(const std::string value) {
122 
123  // Parse JSON string into JSON objects
124  try
125  {
126  const Json::Value root = openshot::stringToJson(value);
127  // Set all values that match
128  SetJsonValue(root);
129  }
130  catch (const std::exception& e)
131  {
132  // Error parsing JSON (or missing keys)
133  throw InvalidJSON("JSON is invalid (missing keys or invalid data types)");
134  }
135 }
136 
137 // Load Json::Value into this object
138 void Brightness::SetJsonValue(const Json::Value root) {
139 
140  // Set parent data
142 
143  // Set data from Json (if key is found)
144  if (!root["brightness"].isNull())
145  brightness.SetJsonValue(root["brightness"]);
146  if (!root["contrast"].isNull())
147  contrast.SetJsonValue(root["contrast"]);
148 }
149 
150 // Get all properties for a specific frame
151 std::string Brightness::PropertiesJSON(int64_t requested_frame) const {
152 
153  // Generate JSON properties list
154  Json::Value root;
155  root["id"] = add_property_json("ID", 0.0, "string", Id(), NULL, -1, -1, true, requested_frame);
156  root["position"] = add_property_json("Position", Position(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
157  root["layer"] = add_property_json("Track", Layer(), "int", "", NULL, 0, 20, false, requested_frame);
158  root["start"] = add_property_json("Start", Start(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
159  root["end"] = add_property_json("End", End(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
160  root["duration"] = add_property_json("Duration", Duration(), "float", "", NULL, 0, 30 * 60 * 60 * 48, true, requested_frame);
161 
162  // Keyframes
163  root["brightness"] = add_property_json("Brightness", brightness.GetValue(requested_frame), "float", "", &brightness, -1.0, 1.0, false, requested_frame);
164  root["contrast"] = add_property_json("Contrast", contrast.GetValue(requested_frame), "float", "", &contrast, 0.0, 100.0, false, requested_frame);
165 
166  // Set the parent effect which properties this effect will inherit
167  root["parent_effect_id"] = add_property_json("Parent", 0.0, "string", info.parent_effect_id, NULL, -1, -1, false, requested_frame);
168 
169  // Return formatted string
170  return root.toStyledString();
171 }
Header file for Brightness class.
Header file for all Exception classes.
Keyframe brightness
Brightness keyframe. A constant value here will prevent animation.
Definition: Brightness.h:59
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: Brightness.h:78
std::string Json() const override
Generate JSON string of this object.
Definition: Brightness.cpp:101
Keyframe contrast
Contrast keyframe.
Definition: Brightness.h:60
void SetJsonValue(const Json::Value root) override
Load Json::Value into this object.
Definition: Brightness.cpp:138
Json::Value JsonValue() const override
Generate Json::Value for this object.
Definition: Brightness.cpp:108
std::string PropertiesJSON(int64_t requested_frame) const override
Definition: Brightness.cpp:151
Brightness()
Blank constructor, useful when using Json to load the effect properties.
Definition: Brightness.cpp:37
void SetJson(const std::string value) override
Load JSON string into this object.
Definition: Brightness.cpp:121
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
float Position() const
Get position on timeline (in seconds)
Definition: ClipBase.h:108
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
virtual Json::Value JsonValue() const
Generate Json::Value for this object.
Definition: EffectBase.cpp:92
int constrain(int color_value)
Constrain a color value from 0 to 255.
Definition: EffectBase.cpp:73
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
std::string parent_effect_id
Id of the parent effect (if there is one)
Definition: EffectBase.h:57
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