OpenShot Library | libopenshot  0.3.3
Public Member Functions | List of all members
openshot::ChromaKey Class Reference

This class removes (i.e. keys out) a color (i.e. greenscreen) More...

#include <effects/ChromaKey.h>

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

 ChromaKey ()
 Blank constructor, useful when using Json to load the effect properties. More...
 
 ChromaKey (Color color, Keyframe fuzz, Keyframe halo=0.0, ChromaKeyMethod method=CHROMAKEY_BASIC)
 Constructor specifying the key color, keying method and distance. 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
 

Additional Inherited Members

- 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...
 
- 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 removes (i.e. keys out) a color (i.e. greenscreen)

The greenscreen / bluescreen effect replaces matching colors in the video image with transparent pixels, revealing lower layers in the timeline.

Definition at line 36 of file ChromaKey.h.

Constructor & Destructor Documentation

◆ ChromaKey() [1/2]

ChromaKey::ChromaKey ( )

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

Definition at line 25 of file ChromaKey.cpp.

◆ ChromaKey() [2/2]

ChromaKey::ChromaKey ( Color  color,
Keyframe  fuzz,
Keyframe  halo = 0.0,
ChromaKeyMethod  method = CHROMAKEY_BASIC 
)

Constructor specifying the key color, keying method and distance.

Standard constructor, which takes an openshot::Color object, a 'fuzz' factor, an optional halo threshold and an optional keying method.

The keying method determines the algorithm to use to determine the distance between the key color and the pixel color. The default keying method, CHROMAKEY_BASIC, treates each of the R,G,B values as a vector and calculates the length of the difference between those vectors.

Pixels that are less than "fuzz" distance from the key color are eliminated by setting their alpha values to zero.

If halo is non-zero, pixels that are withing the halo distance of the fuzz distance are given an alpha value that increases with the distance from the fuzz boundary.

Pixels that are at least as far as fuzz+halo from the key color are foreground pixels and are left intact.

The default method attempts to undo the premultiplication of alpha to find the original color of a pixel. The other methods take the color as is (with alpha premultiplied).

Parameters
colorThe color to match
fuzzThe fuzz factor (or threshold)
haloThe additional threshold for halo elimination.
methodThe keying method

Definition at line 35 of file ChromaKey.cpp.

Member Function Documentation

◆ GetFrame() [1/2]

std::shared_ptr<openshot::Frame> openshot::ChromaKey::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 87 of file ChromaKey.h.

Referenced by GetFrame().

◆ GetFrame() [2/2]

std::shared_ptr< openshot::Frame > ChromaKey::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 100 of file ChromaKey.cpp.

◆ Json()

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

Generate JSON string of this object.

Reimplemented from openshot::EffectBase.

Definition at line 517 of file ChromaKey.cpp.

◆ JsonValue()

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

Generate Json::Value for this object.

Reimplemented from openshot::EffectBase.

Definition at line 524 of file ChromaKey.cpp.

Referenced by Json().

◆ PropertiesJSON()

std::string ChromaKey::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 573 of file ChromaKey.cpp.

◆ SetJson()

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

Load JSON string into this object.

Reimplemented from openshot::EffectBase.

Definition at line 539 of file ChromaKey.cpp.

◆ SetJsonValue()

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

Load Json::Value into this object.

Reimplemented from openshot::EffectBase.

Definition at line 556 of file ChromaKey.cpp.

Referenced by SetJson().


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