Ramping in audio programming refers to the gradual increase or decrease of a signal's amplitude over time. Ramping is commonly used to avoid audible clicks or pops that can occur when abruptly changing the amplitude of a signal.
In audio programming, ramping is often used when starting or stopping audio playback, or when changing the level of an effect or processing chain. For example, when starting a new audio file, the volume can be ramped up gradually over a short period of time to avoid a sudden increase in volume that could cause a click or pop. Similarly, when stopping audio playback, the volume can be ramped down gradually to avoid a sudden decrease in volume.
Ramping can be achieved using various techniques, such as linear or logarithmic fades. A linear fade ramps the amplitude up or down at a constant rate, while a logarithmic fade ramps the amplitude up or down at a rate that gradually slows down over time. The choice of technique depends on the specific application and the desired effect.
Ramping is an important technique in audio programming to ensure smooth and glitch-free transitions between different audio signals or processing chains. It is commonly used in digital audio workstations (DAWs), audio plugins, and other real-time audio processing applications.
Using the Ramping Methods
In Switchboard SDK ramping comes in two flavors,
ramp will apply linear ramping to a single channel audio while
rampInterleaved takes the number of channels as an extra argument and applies ramping to an interleaved audio.
ramp(input, output, startVolume, endVolume, input.size());
rampInterleaved(input, output, startVolume, endVolume, numberOfFrames, numberOfChannels);