Brightness.cpp
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/**
* @file
* @brief Source file for Brightness class
* @author Jonathan Thomas <jonathan@openshot.org>
*
* @section LICENSE
*
* Copyright (c) 2008-2014 OpenShot Studios, LLC
* <http://www.openshotstudios.com/>. This file is part of
* OpenShot Library (libopenshot), an open-source project dedicated to
* delivering high quality video editing and animation solutions to the
* world. For more information visit <http://www.openshot.org/>.
*
* OpenShot Library (libopenshot) is free software: you can redistribute it
* and/or modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* OpenShot Library (libopenshot) is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
*/
#include "../../include/effects/Brightness.h"
using namespace openshot;
/// Blank constructor, useful when using Json to load the effect properties
Brightness::Brightness() : brightness(0.0), contrast(3.0) {
// Init effect properties
init_effect_details();
}
// Default constructor
Brightness::Brightness(Keyframe new_brightness, Keyframe new_contrast) : brightness(new_brightness), contrast(new_contrast)
{
// Init effect properties
init_effect_details();
}
// Init effect settings
void Brightness::init_effect_details()
{
/// Initialize the values of the EffectInfo struct.
InitEffectInfo();
/// Set the effect info
info.class_name = "Brightness";
info.name = "Brightness & Contrast";
info.description = "Adjust the brightness and contrast of the frame's image.";
info.has_audio = false;
info.has_video = true;
}
// This method is required for all derived classes of EffectBase, and returns a
// modified openshot::Frame object
std::shared_ptr<Frame> Brightness::GetFrame(std::shared_ptr<Frame> frame, int64_t frame_number)
{
// Get the frame's image
std::shared_ptr<QImage> frame_image = frame->GetImage();
// Get keyframe values for this frame
float brightness_value = brightness.GetValue(frame_number);
float contrast_value = contrast.GetValue(frame_number);
// Loop through pixels
unsigned char *pixels = (unsigned char *) frame_image->bits();
for (int pixel = 0, byte_index=0; pixel < frame_image->width() * frame_image->height(); pixel++, byte_index+=4)
{
// Get the RGB values from the pixel
int R = pixels[byte_index];
int G = pixels[byte_index + 1];
int B = pixels[byte_index + 2];
int A = pixels[byte_index + 3];
// Adjust the contrast
float factor = (259 * (contrast_value + 255)) / (255 * (259 - contrast_value));
R = constrain((factor * (R - 128)) + 128);
G = constrain((factor * (G - 128)) + 128);
B = constrain((factor * (B - 128)) + 128);
// Adjust the brightness
R += (255 * brightness_value);
G += (255 * brightness_value);
B += (255 * brightness_value);
// Constrain the value from 0 to 255
R = constrain(R);
G = constrain(G);
B = constrain(B);
// Set all pixels to new value
pixels[byte_index] = R;
pixels[byte_index + 1] = G;
pixels[byte_index + 2] = B;
pixels[byte_index + 3] = A; // leave the alpha value alone
}
// return the modified frame
return frame;
}
// Generate JSON string of this object
string Brightness::Json() {
// Return formatted string
return JsonValue().toStyledString();
}
// Generate Json::JsonValue for this object
Json::Value Brightness::JsonValue() {
// Create root json object
Json::Value root = EffectBase::JsonValue(); // get parent properties
root["type"] = info.class_name;
root["brightness"] = brightness.JsonValue();
root["contrast"] = contrast.JsonValue();
// return JsonValue
return root;
}
// Load JSON string into this object
void Brightness::SetJson(string value) {
// Parse JSON string into JSON objects
Json::Value root;
Json::Reader reader;
bool success = reader.parse( value, root );
if (!success)
// Raise exception
throw InvalidJSON("JSON could not be parsed (or is invalid)", "");
try
{
// Set all values that match
SetJsonValue(root);
}
catch (exception e)
{
// Error parsing JSON (or missing keys)
throw InvalidJSON("JSON is invalid (missing keys or invalid data types)", "");
}
}
// Load Json::JsonValue into this object
void Brightness::SetJsonValue(Json::Value root) {
// Set parent data
EffectBase::SetJsonValue(root);
// Set data from Json (if key is found)
if (!root["brightness"].isNull())
brightness.SetJsonValue(root["brightness"]);
if (!root["contrast"].isNull())
contrast.SetJsonValue(root["contrast"]);
}
// Get all properties for a specific frame
string Brightness::PropertiesJSON(int64_t requested_frame) {
// Generate JSON properties list
Json::Value root;
root["id"] = add_property_json("ID", 0.0, "string", Id(), NULL, -1, -1, true, requested_frame);
root["position"] = add_property_json("Position", Position(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
root["layer"] = add_property_json("Track", Layer(), "int", "", NULL, 0, 20, false, requested_frame);
root["start"] = add_property_json("Start", Start(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
root["end"] = add_property_json("End", End(), "float", "", NULL, 0, 30 * 60 * 60 * 48, false, requested_frame);
root["duration"] = add_property_json("Duration", Duration(), "float", "", NULL, 0, 30 * 60 * 60 * 48, true, requested_frame);
// Keyframes
root["brightness"] = add_property_json("Brightness", brightness.GetValue(requested_frame), "float", "", &brightness, -1.0, 1.0, false, requested_frame);
root["contrast"] = add_property_json("Contrast", contrast.GetValue(requested_frame), "float", "", &contrast, 0.0, 100.0, false, requested_frame);
// Return formatted string
return root.toStyledString();
}
OpenShot Wipe Tests.contrast
contrast
Definition: OpenShot Wipe Tests.py:24
openshot::EffectBase::info
EffectInfoStruct info
Information about the current effect.
Definition: EffectBase.h:73
openshot::Brightness::SetJson
void SetJson(string value)
Load JSON string into this object.
Definition: Brightness.cpp:128
openshot::ClipBase::Id
void Id(string value)
Set basic properties.
Definition: ClipBase.h:90
openshot
This namespace is the default namespace for all code in the openshot library.
Definition: AudioBufferSource.h:45
openshot::Brightness::GetFrame
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:61
openshot::EffectInfoStruct::class_name
string class_name
The class name of the effect.
Definition: EffectBase.h:51
openshot::EffectBase::JsonValue
virtual Json::Value JsonValue()=0
Generate Json::JsonValue for this object.
Definition: EffectBase.cpp:81
openshot::Brightness::brightness
Keyframe brightness
Brightness keyframe. A constant value here will prevent animation.
Definition: Brightness.h:66
openshot::ClipBase::add_property_json
Json::Value add_property_json(string name, float value, string type, string memo, Keyframe *keyframe, float min_value, float max_value, bool readonly, int64_t requested_frame)
Generate JSON for a property.
Definition: ClipBase.cpp:65
openshot::Brightness::PropertiesJSON
string PropertiesJSON(int64_t requested_frame)
Definition: Brightness.cpp:164
openshot::Keyframe::GetValue
double GetValue(int64_t index)
Get the value at a specific index.
Definition: KeyFrame.cpp:226
openshot::Keyframe
A Keyframe is a collection of Point instances, which is used to vary a number or property over time.
Definition: KeyFrame.h:64
openshot::Brightness::Json
string Json()
Get and Set JSON methods.
Definition: Brightness.cpp:108
openshot::InvalidJSON
Exception for invalid JSON.
Definition: Exceptions.h:152
OpenShot Wipe Tests.brightness
brightness
Definition: OpenShot Wipe Tests.py:20
openshot::EffectBase::InitEffectInfo
void InitEffectInfo()
Definition: EffectBase.cpp:33
openshot::EffectInfoStruct::has_audio
bool has_audio
Determines if this effect manipulates the audio of a frame.
Definition: EffectBase.h:56
openshot::EffectInfoStruct::description
string description
The description of this effect and what it does.
Definition: EffectBase.h:54
openshot::Brightness::JsonValue
Json::Value JsonValue()
Generate Json::JsonValue for this object.
Definition: Brightness.cpp:115
openshot::Keyframe::JsonValue
Json::Value JsonValue()
Generate Json::JsonValue for this object.
Definition: KeyFrame.cpp:321
openshot::EffectInfoStruct::name
string name
The name of the effect.
Definition: EffectBase.h:53
openshot::Brightness::SetJsonValue
void SetJsonValue(Json::Value root)
Load Json::JsonValue into this object.
Definition: Brightness.cpp:151
openshot::EffectBase::SetJsonValue
virtual void SetJsonValue(Json::Value root)=0
Load Json::JsonValue into this object.
Definition: EffectBase.cpp:121
OpenShot Wipe Tests.e
e
Definition: OpenShot Wipe Tests.py:28
openshot::EffectInfoStruct::has_video
bool has_video
Determines if this effect manipulates the image of a frame.
Definition: EffectBase.h:55
openshot::Brightness::Brightness
Brightness()
Blank constructor, useful when using Json to load the effect properties.
Definition: Brightness.cpp:33
openshot::EffectBase::constrain
int constrain(int color_value)
Constrain a color value from 0 to 255.
Definition: EffectBase.cpp:62
openshot::Brightness::contrast
Keyframe contrast
Contrast keyframe.
Definition: Brightness.h:67
openshot::Keyframe::SetJsonValue
void SetJsonValue(Json::Value root)
Load Json::JsonValue into this object.
Definition: KeyFrame.cpp:362