OpenShot Library | libopenshot  0.3.2
Public Member Functions | Public Attributes | List of all members
openshot::Caption Class Reference

This class adds captions/text over a video, based on timestamps. You can also animate some limited aspects, such as words appearing/disappearing. More...

#include <effects/Caption.h>

Inheritance diagram for openshot::Caption:
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Collaboration diagram for openshot::Caption:
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Public Member Functions

 Caption ()
 Blank constructor, useful when using Json to load the effect properties. More...
 
 Caption (std::string captions)
 
std::string CaptionText ()
 Set the caption string to use (see VTT format) More...
 
void CaptionText (std::string new_caption_text)
 Get the caption string. More...
 
std::shared_ptr< openshot::FrameGetFrame (int64_t frame_number) override
 This method is required for all derived classes of ClipBase, and returns a new openshot::Frame object. All Clip keyframes and effects are resolved into pixels. More...
 
std::shared_ptr< openshot::FrameGetFrame (std::shared_ptr< openshot::Frame > frame, int64_t frame_number) override
 This method is required for all derived classes of ClipBase, and returns a modified openshot::Frame object. More...
 
std::string Json () const override
 Generate JSON string of this object. More...
 
Json::Value JsonValue () const override
 Generate Json::Value for this object. More...
 
std::string PropertiesJSON (int64_t requested_frame) const override
 
void SetJson (const std::string value) override
 Load JSON string into this object. More...
 
void SetJsonValue (const Json::Value root) override
 Load Json::Value into this object. More...
 
- Public Member Functions inherited from openshot::EffectBase
Json::Value BasePropertiesJSON (int64_t requested_frame) const
 Generate JSON object of base properties (recommended to be used by all effects) More...
 
int constrain (int color_value)
 Constrain a color value from 0 to 255. More...
 
void DisplayInfo (std::ostream *out=&std::cout)
 Display effect information in the standard output stream (stdout) More...
 
virtual std::string GetVisibleObjects (int64_t frame_number) const
 Get the indexes and IDs of all visible objects in the given frame. More...
 
void InitEffectInfo ()
 
virtual std::string Json (int64_t requested_frame) const
 
Json::Value JsonInfo () const
 Generate JSON object of meta data / info. More...
 
int Order () const
 Get the order that this effect should be executed. More...
 
void Order (int new_order)
 Set the order that this effect should be executed. More...
 
openshot::ClipBaseParentClip ()
 Parent clip object of this effect (which can be unparented and NULL) More...
 
void ParentClip (openshot::ClipBase *new_clip)
 Set parent clip object of this effect. More...
 
std::string ParentClipId () const
 Return the ID of this effect's parent clip. More...
 
virtual void SetJson (int64_t requested_frame, const std::string value)
 
void SetParentEffect (std::string parentEffect_id)
 Set the parent effect from which this properties will be set to. More...
 
virtual ~EffectBase ()=default
 
- Public Member Functions inherited from openshot::ClipBase
 ClipBase ()
 Constructor for the base clip. More...
 
virtual void End (float value)
 Set end position (in seconds) of clip (trim end of video) More...
 
void Id (std::string value)
 
void Layer (int value)
 Set layer of clip on timeline (lower number is covered by higher numbers) More...
 
bool operator< (ClipBase &a)
 
bool operator<= (ClipBase &a)
 
bool operator> (ClipBase &a)
 
bool operator>= (ClipBase &a)
 
void Position (float value)
 

Set the Id of this clip object

More...
 
void Start (float value)
 Set start position (in seconds) of clip (trim start of video) More...
 
virtual ~ClipBase ()=default
 

Public Attributes

Color background
 Color of caption area background. More...
 
Keyframe background_alpha
 Background color alpha. More...
 
Keyframe background_corner
 Background cornder radius. More...
 
Keyframe background_padding
 Background padding. More...
 
Color color
 Color of caption text. More...
 
Keyframe fade_in
 Fade in per caption (# of seconds) More...
 
Keyframe fade_out
 Fade in per caption (# of seconds) More...
 
Keyframe font_alpha
 Font color alpha. More...
 
std::string font_name
 Font string. More...
 
Keyframe font_size
 Font size in points. More...
 
Keyframe left
 Size of left bar. More...
 
Keyframe line_spacing
 Distance between lines (1.0 default / 100%) More...
 
Keyframe right
 Size of right bar. More...
 
Color stroke
 Color of text border / stroke. More...
 
Keyframe stroke_width
 Width of text border / stroke. More...
 
Keyframe top
 Size of top bar. More...
 
- Public Attributes inherited from openshot::EffectBase
EffectInfoStruct info
 Information about the current effect. More...
 
EffectBaseparentEffect
 Parent effect (which properties will set this effect properties) More...
 
std::map< int, std::shared_ptr< openshot::TrackedObjectBase > > trackedObjects
 Map of Tracked Object's by their indices (used by Effects that track objects on clips) More...
 

Additional Inherited Members

- Protected Member Functions inherited from openshot::ClipBase
Json::Value add_property_choice_json (std::string name, int value, int selected_value) const
 Generate JSON choice for a property (dropdown properties) More...
 
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. More...
 
- Protected Attributes inherited from openshot::EffectBase
openshot::ClipBaseclip
 Pointer to the parent clip instance (if any) More...
 
- Protected Attributes inherited from openshot::ClipBase
float end
 The position in seconds to end playing (used to trim the ending of a clip) More...
 
std::string id
 ID Property for all derived Clip and Effect classes. More...
 
int layer
 The layer this clip is on. Lower clips are covered up by higher clips. More...
 
float position
 The position on the timeline where this clip should start playing. More...
 
std::string previous_properties
 This string contains the previous JSON properties. More...
 
float start
 The position in seconds to start playing (used to trim the beginning of a clip) More...
 
openshot::TimelineBasetimeline
 Pointer to the parent timeline instance (if any) More...
 

Detailed Description

This class adds captions/text over a video, based on timestamps. You can also animate some limited aspects, such as words appearing/disappearing.

Adding captions can be an easy way to generate text overlays through-out a long clip.

Definition at line 38 of file Caption.h.

Constructor & Destructor Documentation

◆ Caption() [1/2]

Caption::Caption ( )

Blank constructor, useful when using Json to load the effect properties.

Definition at line 30 of file Caption.cpp.

◆ Caption() [2/2]

Caption::Caption ( std::string  captions)

Default constructor, which takes a string of VTT/Subrip formatted caption data, and displays them over time.

Parameters
captionsA string with VTT/Subrip format text captions

Definition at line 39 of file Caption.cpp.

Member Function Documentation

◆ CaptionText() [1/2]

std::string Caption::CaptionText ( )

Set the caption string to use (see VTT format)

Definition at line 69 of file Caption.cpp.

◆ CaptionText() [2/2]

void Caption::CaptionText ( std::string  new_caption_text)

Get the caption string.

Definition at line 74 of file Caption.cpp.

◆ GetFrame() [1/2]

std::shared_ptr<openshot::Frame> openshot::Caption::GetFrame ( int64_t  frame_number)
inlineoverridevirtual

This method is required for all derived classes of ClipBase, and returns a new openshot::Frame object. All Clip keyframes and effects are resolved into pixels.

Returns
A new openshot::Frame object
Parameters
frame_numberThe frame number (starting at 1) of the clip or effect on the timeline.

Implements openshot::ClipBase.

Definition at line 86 of file Caption.h.

Referenced by GetFrame().

◆ GetFrame() [2/2]

std::shared_ptr< openshot::Frame > Caption::GetFrame ( std::shared_ptr< openshot::Frame frame,
int64_t  frame_number 
)
overridevirtual

This method is required for all derived classes of ClipBase, and returns a modified openshot::Frame object.

The frame object is passed into this method and used as a starting point (pixels and audio). All Clip keyframes and effects are resolved into pixels.

Returns
The modified openshot::Frame object
Parameters
frameThe frame object that needs the clip or effect applied to it
frame_numberThe frame number (starting at 1) of the clip or effect on the timeline.

Implements openshot::ClipBase.

Definition at line 108 of file Caption.cpp.

◆ Json()

std::string Caption::Json ( ) const
overridevirtual

Generate JSON string of this object.

Reimplemented from openshot::EffectBase.

Definition at line 356 of file Caption.cpp.

◆ JsonValue()

Json::Value Caption::JsonValue ( ) const
overridevirtual

Generate Json::Value for this object.

Reimplemented from openshot::EffectBase.

Definition at line 363 of file Caption.cpp.

Referenced by Json().

◆ PropertiesJSON()

std::string Caption::PropertiesJSON ( int64_t  requested_frame) const
overridevirtual

Get all properties for a specific frame (perfect for a UI to display the current state of all properties at any time)

Implements openshot::ClipBase.

Definition at line 454 of file Caption.cpp.

◆ SetJson()

void Caption::SetJson ( const std::string  value)
overridevirtual

Load JSON string into this object.

Reimplemented from openshot::EffectBase.

Definition at line 391 of file Caption.cpp.

◆ SetJsonValue()

void Caption::SetJsonValue ( const Json::Value  root)
overridevirtual

Load Json::Value into this object.

Reimplemented from openshot::EffectBase.

Definition at line 408 of file Caption.cpp.

Referenced by SetJson().

Member Data Documentation

◆ background

Color openshot::Caption::background

Color of caption area background.

Definition at line 57 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ background_alpha

Keyframe openshot::Caption::background_alpha

Background color alpha.

Definition at line 58 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ background_corner

Keyframe openshot::Caption::background_corner

Background cornder radius.

Definition at line 59 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ background_padding

Keyframe openshot::Caption::background_padding

Background padding.

Definition at line 60 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ color

Color openshot::Caption::color

Color of caption text.

Definition at line 55 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ fade_in

Keyframe openshot::Caption::fade_in

Fade in per caption (# of seconds)

Definition at line 68 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ fade_out

Keyframe openshot::Caption::fade_out

Fade in per caption (# of seconds)

Definition at line 69 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ font_alpha

Keyframe openshot::Caption::font_alpha

Font color alpha.

Definition at line 63 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ font_name

std::string openshot::Caption::font_name

Font string.

Definition at line 70 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ font_size

Keyframe openshot::Caption::font_size

Font size in points.

Definition at line 62 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ left

Keyframe openshot::Caption::left

Size of left bar.

Definition at line 65 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ line_spacing

Keyframe openshot::Caption::line_spacing

Distance between lines (1.0 default / 100%)

Definition at line 64 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ right

Keyframe openshot::Caption::right

Size of right bar.

Definition at line 67 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ stroke

Color openshot::Caption::stroke

Color of text border / stroke.

Definition at line 56 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ stroke_width

Keyframe openshot::Caption::stroke_width

Width of text border / stroke.

Definition at line 61 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().

◆ top

Keyframe openshot::Caption::top

Size of top bar.

Definition at line 66 of file Caption.h.

Referenced by GetFrame(), JsonValue(), PropertiesJSON(), and SetJsonValue().


The documentation for this class was generated from the following files: