OpenShot Library | libopenshot 0.2.7
Caption.h
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1/**
2 * @file
3 * @brief Header file for Caption effect 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_CAPTION_EFFECT_H
32#define OPENSHOT_CAPTION_EFFECT_H
33
34#include <memory>
35#include <string>
36#include <vector>
37#include <QFont>
38#include <QFontMetrics>
39#include <QRegularExpression>
40#include "../Color.h"
41#include "../EffectBase.h"
42#include "../Json.h"
43#include "../KeyFrame.h"
44
45
46
47namespace openshot
48{
49
50/**
51 * @brief This class adds captions/text over a video, based on timestamps. You can also animate some limited
52 * aspects, such as words appearing/disappearing.
53 *
54 * Adding captions can be an easy way to generate text overlays through-out a long clip.
55 */
56class Caption : public EffectBase
57{
58private:
59 std::vector<QRegularExpressionMatch> matchedCaptions; ///< RegEx to capture cues and text
60 std::string caption_text; ///< Text of caption
61 QFontMetrics* metrics; ///< Font metrics object
62 QFont* font; ///< QFont object
63 bool is_dirty;
64
65 /// Init effect settings
66 void init_effect_details();
67
68 /// Process regex capture
69 void process_regex();
70
71
72public:
73 Color color; ///< Color of caption text
74 Color stroke; ///< Color of text border / stroke
75 Color background; ///< Color of caption area background
76 Keyframe background_alpha; ///< Background color alpha
77 Keyframe background_corner; ///< Background cornder radius
78 Keyframe background_padding; ///< Background padding
79 Keyframe stroke_width; ///< Width of text border / stroke
80 Keyframe font_size; ///< Font size in points
81 Keyframe font_alpha; ///< Font color alpha
82 Keyframe left; ///< Size of left bar
83 Keyframe top; ///< Size of top bar
84 Keyframe right; ///< Size of right bar
85 Keyframe fade_in; ///< Fade in per caption (# of seconds)
86 Keyframe fade_out; ///< Fade in per caption (# of seconds)
87 std::string font_name; ///< Font string
88
89 /// Blank constructor, useful when using Json to load the effect properties
90 Caption();
91
92 /// Default constructor, which takes a string of VTT/Subrip formatted caption data, and displays them over time.
93 ///
94 /// @param captions A string with VTT/Subrip format text captions
95 Caption(std::string captions);
96
97 /// @brief This method is required for all derived classes of ClipBase, and returns a
98 /// new openshot::Frame object. All Clip keyframes and effects are resolved into
99 /// pixels.
100 ///
101 /// @returns A new openshot::Frame object
102 /// @param frame_number The frame number (starting at 1) of the clip or effect on the timeline.
103 std::shared_ptr<openshot::Frame> GetFrame(int64_t frame_number) override { return GetFrame(std::make_shared<openshot::Frame>(), frame_number); }
104
105 /// @brief This method is required for all derived classes of ClipBase, and returns a
106 /// modified openshot::Frame object
107 ///
108 /// The frame object is passed into this method and used as a starting point (pixels and audio).
109 /// All Clip keyframes and effects are resolved into pixels.
110 ///
111 /// @returns The modified openshot::Frame object
112 /// @param frame The frame object that needs the clip or effect applied to it
113 /// @param frame_number The frame number (starting at 1) of the clip or effect on the timeline.
114 std::shared_ptr<openshot::Frame> GetFrame(std::shared_ptr<openshot::Frame> frame, int64_t frame_number) override;
115
116 // Get and Set caption data
117 std::string CaptionText(); ///< Set the caption string to use (see VTT format)
118 void CaptionText(std::string new_caption_text); ///< Get the caption string
119
120 // Get and Set JSON methods
121 std::string Json() const override; ///< Generate JSON string of this object
122 void SetJson(const std::string value) override; ///< Load JSON string into this object
123 Json::Value JsonValue() const override; ///< Generate Json::Value for this object
124 void SetJsonValue(const Json::Value root) override; ///< Load Json::Value into this object
125
126 /// Get all properties for a specific frame (perfect for a UI to display the current state
127 /// of all properties at any time)
128 std::string PropertiesJSON(int64_t requested_frame) const override;
129};
130
131} // namespace openshot
132
133#endif // OPENSHOT_CAPTION_EFFECT_H
This class adds captions/text over a video, based on timestamps. You can also animate some limited as...
Definition: Caption.h:57
std::string PropertiesJSON(int64_t requested_frame) const override
Definition: Caption.cpp:394
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: Caption.h:103
Keyframe background_padding
Background padding.
Definition: Caption.h:78
Caption()
Blank constructor, useful when using Json to load the effect properties.
Definition: Caption.cpp:45
Keyframe stroke_width
Width of text border / stroke.
Definition: Caption.h:79
Json::Value JsonValue() const override
Generate Json::Value for this object.
Definition: Caption.cpp:306
void SetJsonValue(const Json::Value root) override
Load Json::Value into this object.
Definition: Caption.cpp:350
std::string Json() const override
Generate JSON string of this object.
Definition: Caption.cpp:299
void SetJson(const std::string value) override
Load JSON string into this object.
Definition: Caption.cpp:333
std::string font_name
Font string.
Definition: Caption.h:87
Color background
Color of caption area background.
Definition: Caption.h:75
Keyframe font_size
Font size in points.
Definition: Caption.h:80
Keyframe font_alpha
Font color alpha.
Definition: Caption.h:81
Keyframe background_alpha
Background color alpha.
Definition: Caption.h:76
Keyframe fade_out
Fade in per caption (# of seconds)
Definition: Caption.h:86
Keyframe background_corner
Background cornder radius.
Definition: Caption.h:77
Keyframe fade_in
Fade in per caption (# of seconds)
Definition: Caption.h:85
Keyframe top
Size of top bar.
Definition: Caption.h:83
Color stroke
Color of text border / stroke.
Definition: Caption.h:74
std::string CaptionText()
Set the caption string to use (see VTT format)
Definition: Caption.cpp:83
Keyframe right
Size of right bar.
Definition: Caption.h:84
Color color
Color of caption text.
Definition: Caption.h:73
Keyframe left
Size of left bar.
Definition: Caption.h:82
This class represents a color (used on the timeline and clips)
Definition: Color.h:45
This abstract class is the base class, used by all effects in libopenshot.
Definition: EffectBase.h:71
A Keyframe is a collection of Point instances, which is used to vary a number or property over time.
Definition: KeyFrame.h:72
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:47