GstAudioVisualizer

GstAudioVisualizer — Base class for visualizers.

Functions

Properties

Types and Values

Object Hierarchy

    GEnum
    ╰── GstAudioVisualizerShader
    GObject
    ╰── GInitiallyUnowned
        ╰── GstObject
            ╰── GstElement
                ╰── GstAudioVisualizer

Includes

#include <gst/pbutils/pbutils.h>

Description

A baseclass for scopes (visualizers). It takes care of re-fitting the audio-rate to video-rate and handles renegotiation (downstream video size changes).

It also provides several background shading effects. These effects are applied to a previous picture before the render() implementation can draw a new frame.

Functions

GstAudioVisualizerShaderFunc ()

void
(*GstAudioVisualizerShaderFunc) (GstAudioVisualizer *scope,
                                 const GstVideoFrame *s,
                                 GstVideoFrame *d);

Types and Values

struct GstAudioVisualizer

struct GstAudioVisualizer;

struct GstAudioVisualizerClass

struct GstAudioVisualizerClass {
  /* virtual function, called whenever the format changes */
  gboolean (*setup) (GstAudioVisualizer * scope);

  /* virtual function for rendering a frame */
  gboolean (*render) (GstAudioVisualizer * scope, GstBuffer * audio, GstVideoFrame * video);

  gboolean (*decide_allocation)   (GstAudioVisualizer * scope, GstQuery *query);
};

enum GstAudioVisualizerShader

Different types of supported background shading functions.

Members

GST_AUDIO_VISUALIZER_SHADER_NONE

no shading

 

GST_AUDIO_VISUALIZER_SHADER_FADE

plain fading

 

GST_AUDIO_VISUALIZER_SHADER_FADE_AND_MOVE_UP

fade and move up

 

GST_AUDIO_VISUALIZER_SHADER_FADE_AND_MOVE_DOWN

fade and move down

 

GST_AUDIO_VISUALIZER_SHADER_FADE_AND_MOVE_LEFT

fade and move left

 

GST_AUDIO_VISUALIZER_SHADER_FADE_AND_MOVE_RIGHT

fade and move right

 

GST_AUDIO_VISUALIZER_SHADER_FADE_AND_MOVE_HORIZ_OUT

fade and move horizontally out

 

GST_AUDIO_VISUALIZER_SHADER_FADE_AND_MOVE_HORIZ_IN

fade and move horizontally in

 

GST_AUDIO_VISUALIZER_SHADER_FADE_AND_MOVE_VERT_OUT

fade and move vertically out

 

GST_AUDIO_VISUALIZER_SHADER_FADE_AND_MOVE_VERT_IN

fade and move vertically in

 

Property Details

The “shade-amount” property

  “shade-amount”             guint

Shading color to use (big-endian ARGB).

Flags: Read / Write

Default value: 657930


The “shader” property

  “shader”                   GstAudioVisualizerShader

Shader function to apply on each frame.

Flags: Read / Write

Default value: GST_AUDIO_VISUALIZER_SHADER_FADE