alpha

alpha — Adds an alpha channel to video - uniform or via chroma-keying

Synopsis

struct              GstAlpha;
enum                GstAlphaMethod;

Object Hierarchy

  GObject
   +----GInitiallyUnowned
         +----GstObject
               +----GstElement
                     +----GstBaseTransform
                           +----GstVideoFilter
                                 +----GstAlpha

Properties

  "alpha"                    gdouble               : Read / Write
  "angle"                    gfloat                : Read / Write
  "method"                   GstAlphaMethod        : Read / Write
  "noise-level"              gfloat                : Read / Write
  "target-b"                 guint                 : Read / Write
  "target-g"                 guint                 : Read / Write
  "target-r"                 guint                 : Read / Write
  "black-sensitivity"        guint                 : Read / Write
  "white-sensitivity"        guint                 : Read / Write
  "prefer-passthrough"       gboolean              : Read / Write

Description

The alpha element adds an alpha channel to a video stream. The values of the alpha channel can be either be set to a constant or can be dynamically calculated via chroma keying, e.g. blue can be set as the transparent color.

Sample pipeline: 

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