Audio Spectrum Filter¶

Description

This effect/filter is an audio visualization effect that draws an audio spectrum on the image. It can be controlled directly on the monitor.

Parameters

Parameter	Value	Description
Graph type	Selection	Select the type of graph to display the levels
Fill	Switch	If checked, fills the area under the graph. Only applies to Graph type Line.
Mirror	Switch	If checked, mirrors the spectrum on the center line of the rectangle
Reverse	Switch	If checked, draws the points starting with the highest frequency
Window size	Integer	The number of samples that the FFT[1] will be performed on. If Window size is less than the number of samples in a frame, extra samples will be ignored. If Window size is more than the number of samples in a frame, samples will be buffered from previous frames to fill the window. The buffering is performed as a sliding window so that the most recent samples are always transformed.
Background Color	Picker	Defines the background color to be applied to the entire frame
Foreground color	Picker	Defines the color of the waveform
Line Thickness	Integer	Defines the thickness of the bar or line in number of pixels
Angle	Integer	Defines the rotation angle to be applied to the waveform
X / Y / W / H / Size / Opacity		Defines the X and Y coordinates, Width and Height, Size and Opacity of the rectangle in which the waveform is drawn. The icons help in lining up the rectangle.
Line Tension	Integer	Affects the amount of curve in the line interpolating between points. 0 draws a straight line between points; 100 draws very curved lines between points. Values below 0 and above 100 will cause loops in the lines. Only applies to Graph type Line.
Points	Integer	Defines the number of bands to draw in the spectrum. Each band shows up as a data point in the graph.
Low Frequency	Integer	The low end of the frequency range to be used for the graph (Hz)
High Frequency	Integer	The high end of the frequency range to be used for the graph (Hz)
Level Threshold	Integer	The minimum amplitude of sound that must occur within the frequency range to cause the value to be applied (dB)

The following selection items are available:

Graph type

Line
Bar

Note

The effect is not updated in the Project Monitor during scrubbing. You need to play back the project to see this effect.

Tip

Opacity is fixed at 100%. You control the opacity/transparency of the effect by adjusting the alpha component of the Foreground color.

Example

Line Thickness set to 4