FFT Audio Analysis
 | FFT Audio Analysis | This node analysis sounds and provides 16 different frequency band characteristics. |
Ventuz provides real-time audio analysis for creating graphics that react on sound sources. This can be used to create custom graphical equalizers of any kind of show and exhibition enhancements with audience interacting with the graphics via sound.
The FFT (Fast Fourier Transformation) node analyses the audio frequencies of a sound source and outputs overall volume and intensity levels. The levels are split in 16 bands (output properties Band00 to Band15). The lower band properties represent the intensity of lower frequencies, the upper band values those of the higher frequencies of a sound source.
The input property Active enables and disables this node. The property Channels defines which stereo channel should be analyzed. In case of LeftRight a sum of both channels is analyzed. The Ordinal property specifies the audio capture device that should provide the audio data for analysis. The Softness property can be used to interpolate all value outputs to avoid abrupt value changes. This smooths the values over time and results in softer animations.
To avoid unnecessay performance problems, only one FFT Audio Analysis node should be used per sound source.
Audio Configuration
To listen to a Ventuz Audio device you have to configure them in the Ventuz Audio Video Configuration. In the Cross Point section you can add and remove virtual audio cables. I.e. you can add a cable Ventuz A --> Ventuz A to listen to the first stereo pair of the Ventuz Audio device.
The first Cable is necessary to make the FFT node listen to audio and sound played by Ventuz.
The second Cable is only necessary if the audio should be forwarded to an audio hardware in the Ventuz machine.