OpenShot Library | libopenshot  0.2.6
Mask.h
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1 /**
2  * @file
3  * @brief Header file for Mask 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 #ifndef OPENSHOT_MASK_EFFECT_H
32 #define OPENSHOT_MASK_EFFECT_H
33 
34 #include "../EffectBase.h"
35 
36 #include "../Json.h"
37 #include "../KeyFrame.h"
38 
39 #include <string>
40 #include <memory>
41 
42 namespace openshot
43 {
44  // Forward declaration
45  class ReaderBase;
46 
47  /**
48  * @brief This class uses the image libraries to apply alpha (or transparency) masks
49  * to any frame. It can also be animated, and used as a powerful Wipe transition.
50  *
51  * These masks / wipes can also be combined, such as a transparency mask on top of a clip, which
52  * is then wiped away with another animated version of this effect.
53  */
54  class Mask : public EffectBase
55  {
56  private:
57  ReaderBase *reader;
58  std::shared_ptr<QImage> original_mask;
59  bool needs_refresh;
60 
61  /// Init effect settings
62  void init_effect_details();
63 
64  public:
65  bool replace_image; ///< Replace the frame image with a grayscale image representing the mask. Great for debugging a mask.
66  Keyframe brightness; ///< Brightness keyframe to control the wipe / mask effect. A constant value here will prevent animation.
67  Keyframe contrast; ///< Contrast keyframe to control the hardness of the wipe effect / mask.
68 
69  /// Blank constructor, useful when using Json to load the effect properties
70  Mask();
71 
72  /// Default constructor, which takes 2 curves and a mask image path. The mask is used to
73  /// determine the alpha for each pixel (black is transparent, white is visible). The curves
74  /// adjust the brightness and contrast of this file, to animate the effect.
75  ///
76  /// @param mask_reader The reader of a grayscale mask image or video, to be used by the wipe transition
77  /// @param mask_brightness The curve to adjust the brightness of the wipe's mask (between 100 and -100)
78  /// @param mask_contrast The curve to adjust the contrast of the wipe's mask (3 is typical, 20 is a lot, 0 is invalid)
79  Mask(ReaderBase *mask_reader, Keyframe mask_brightness, Keyframe mask_contrast);
80 
81  /// @brief This method is required for all derived classes of ClipBase, and returns a
82  /// new openshot::Frame object. All Clip keyframes and effects are resolved into
83  /// pixels.
84  ///
85  /// @returns A new openshot::Frame object
86  /// @param frame_number The frame number (starting at 1) of the clip or effect on the timeline.
87  std::shared_ptr<openshot::Frame> GetFrame(int64_t frame_number) override { return GetFrame(std::make_shared<openshot::Frame>(), frame_number); }
88 
89  /// @brief This method is required for all derived classes of ClipBase, and returns a
90  /// modified openshot::Frame object
91  ///
92  /// The frame object is passed into this method and used as a starting point (pixels and audio).
93  /// All Clip keyframes and effects are resolved into pixels.
94  ///
95  /// @returns The modified openshot::Frame object
96  /// @param frame The frame object that needs the clip or effect applied to it
97  /// @param frame_number The frame number (starting at 1) of the clip or effect on the timeline.
98  std::shared_ptr<openshot::Frame> GetFrame(std::shared_ptr<openshot::Frame> frame, int64_t frame_number) override;
99 
100  // Get and Set JSON methods
101  std::string Json() const override; ///< Generate JSON string of this object
102  void SetJson(const std::string value) override; ///< Load JSON string into this object
103  Json::Value JsonValue() const override; ///< Generate Json::Value for this object
104  void SetJsonValue(const Json::Value root) override; ///< Load Json::Value into this object
105 
106  /// Get all properties for a specific frame (perfect for a UI to display the current state
107  /// of all properties at any time)
108  std::string PropertiesJSON(int64_t requested_frame) const override;
109 
110  /// Get the reader object of the mask grayscale image
111  ReaderBase* Reader() { return reader; };
112 
113  /// Set a new reader to be used by the mask effect (grayscale image)
114  void Reader(ReaderBase *new_reader) { reader = new_reader; };
115  };
116 
117 }
118 
119 #endif
Json::Value JsonValue() const override
Generate Json::Value for this object.
Definition: Mask.cpp:169
This abstract class is the base class, used by all effects in libopenshot.
Definition: EffectBase.h:70
bool replace_image
Replace the frame image with a grayscale image representing the mask. Great for debugging a mask...
Definition: Mask.h:65
void Reader(ReaderBase *new_reader)
Set a new reader to be used by the mask effect (grayscale image)
Definition: Mask.h:114
This abstract class is the base class, used by all readers in libopenshot.
Definition: ReaderBase.h:97
ReaderBase * Reader()
Get the reader object of the mask grayscale image.
Definition: Mask.h:111
Keyframe contrast
Contrast keyframe to control the hardness of the wipe effect / mask.
Definition: Mask.h:67
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: Mask.h:87
Mask()
Blank constructor, useful when using Json to load the effect properties.
Definition: Mask.cpp:42
This class uses the image libraries to apply alpha (or transparency) masks to any frame...
Definition: Mask.h:54
std::string PropertiesJSON(int64_t requested_frame) const override
Definition: Mask.cpp:271
void SetJson(const std::string value) override
Load JSON string into this object.
Definition: Mask.cpp:187
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:46
void SetJsonValue(const Json::Value root) override
Load Json::Value into this object.
Definition: Mask.cpp:204
Keyframe brightness
Brightness keyframe to control the wipe / mask effect. A constant value here will prevent animation...
Definition: Mask.h:66
std::string Json() const override
Generate JSON string of this object.
Definition: Mask.cpp:162
A Keyframe is a collection of Point instances, which is used to vary a number or property over time...
Definition: KeyFrame.h:72