BgReplacePlugin
Background replace plugin
@geenee/armature!ShaderPlugin replaces background region of an image. Segmentation mask defines image foreground that stays untouched. Foreground-background classification is based on two thresholds defining uncertainty interval. Probability above foreground threshold classifies pixel as foreground, below background threshold as background. FG pixels are kept untouched, BG pixels are replaced with corresponding pixels from the background texture. For pixels within uncertainty region weighted interpolation between image and background textures takes place. Weight is evaluated by scaling uncertainty interval and probability to [0..1]. Plugin depends on @geenee/bodyrenderers-common!MaskUploadPlugin that must be attached to the renderer to upload mask buffer in texture. One may utilize a @geenee/bodyrenderers-common!MaskUpscalePlugin providing higher resolution segmentation mask that significantly increases accuracy of patching and reduces the size of the patch region. Other mask post-processing plugins may be used to fine-tune for particular use case.
Extends
Section titled “Extends”Constructors
Section titled “Constructors”Constructor
Section titled “Constructor”new BgReplacePlugin(
threshBg,threshFg,mirror):BgReplacePlugin
Constructor
Parameters
Section titled “Parameters”threshBg
Section titled “threshBg”number = 0.4
Background threshold
threshFg
Section titled “threshFg”number = 0.6
Foreground threshold
mirror
Section titled “mirror”boolean = false
Mirror background
Returns
Section titled “Returns”BgReplacePlugin
Overrides
Section titled “Overrides”Properties
Section titled “Properties”bgTexture?
Section titled “bgTexture?”
protectedoptionalbgTexture:ImageTexture
Background texture
fragSrc?
Section titled “fragSrc?”
protectedoptionalfragSrc:string
Code of fragment shader (copy shader by default)
Inherited from
Section titled “Inherited from”inputs?
Section titled “inputs?”
protectedoptionalinputs:string[]
Shader texture inputs (names of sampler uniforms)
Inherited from
Section titled “Inherited from”loaded
Section titled “loaded”loaded:
boolean
Loaded state
Inherited from
Section titled “Inherited from”mirror
Section titled “mirror”
protectedmirror:boolean=false
Mirror background
ordinal
Section titled “ordinal”ordinal:
number
Ordinal number
Inherited from
Section titled “Inherited from”renderer?
Section titled “renderer?”
protectedoptionalrenderer:Renderer<SegmentationResult>
Renderer loaded the plugin
Inherited from
Section titled “Inherited from”shader?
Section titled “shader?”
protectedoptionalshader:ShaderProgram
Rendering shader
Inherited from
Section titled “Inherited from”shaderCtx?
Section titled “shaderCtx?”
protectedoptionalshaderCtx:WebGL2RenderingContext
Rendering context
Inherited from
Section titled “Inherited from”
protectedsize:Size
Image size
Inherited from
Section titled “Inherited from”uniforms?
Section titled “uniforms?”
protectedoptionaluniforms:object
Shader uniforms as name-type map object
Index Signature
Section titled “Index Signature”[key: string]: UniformType
Inherited from
Section titled “Inherited from”vertSrc?
Section titled “vertSrc?”
protectedoptionalvertSrc:string
Vertex shader source (copy shader by default)
Inherited from
Section titled “Inherited from”Methods
Section titled “Methods”background()
Section titled “background()”background():
undefined|ImageTexture
Texture replacing a background
Returns
Section titled “Returns”undefined | ImageTexture
Background texture
dispose()
Section titled “dispose()”dispose():
void
Dispose video plugin
Returns
Section titled “Returns”void
Inherited from
Section titled “Inherited from”load()
Section titled “load()”load(
renderer):Promise<void>
Initialize plugin
Initializes resources required for shader effect. Allocates texture that will replace background.
Parameters
Section titled “Parameters”renderer
Section titled “renderer”Renderer this plugin is attached to
Returns
Section titled “Returns”Promise<void>
Promise resolving when initialization is finished
Overrides
Section titled “Overrides”process()
Section titled “process()”process(
result,input):Promise<boolean>
Process the image
Applies background replacement with texture.
Parameters
Section titled “Parameters”result
Section titled “result”Results of video processing
WebGLTexture
Current image texture
Returns
Section titled “Returns”Promise<boolean>
True on success, false otherwise
Overrides
Section titled “Overrides”setMirror()
Section titled “setMirror()”setMirror(
mirror):void
Set background mirror mode
Parameters
Section titled “Parameters”mirror
Section titled “mirror”boolean
Mirror flag
Returns
Section titled “Returns”void
setupCamera()
Section titled “setupCamera()”setupCamera(
ratio,angle):void
Set camera parameters
Could be overridden to adjust plugin’s pipeline.
Parameters
Section titled “Parameters”number
Aspect ration of input video
number
Vertical field of view in radians
Returns
Section titled “Returns”void
Inherited from
Section titled “Inherited from”setupVideo()
Section titled “setupVideo()”setupVideo(
size):void
Set video size
Adjusts shader and texture to a new size.
Parameters
Section titled “Parameters”Resolution of input video
Returns
Section titled “Returns”void
Overrides
Section titled “Overrides”unload()
Section titled “unload()”unload():
void
Reset plugin
Releases all resources and instances created in load().
Returns
Section titled “Returns”void
Overrides
Section titled “Overrides”update()
Section titled “update()”update(
result,stream):Promise<void>
Sealed
Update the image
Main method implementing webgl shader effect or filter. ShaderRenderer keeps track of the current iamge texture that will be be rendered. ShaderPlugin uses the current texture as input and writes results to ShaderPlugin#output. ShaderPlugin#output becomes new current texture of ShaderRenderer. This way all ShaderPlugins attached to renderer organize a chain of effects applied on top of each other. Method process() implements shader effect itself, it’s intended to be overridden by effect authors.
Parameters
Section titled “Parameters”result
Section titled “result”Results of video processing
stream
Section titled “stream”HTMLCanvasElement
Captured video frame
Returns
Section titled “Returns”Promise<void>
Promise resolving when update is finished