Useful code snippets and interesting coding ideas.
When calling a function we commonly pass one or more parameters to that function. In most cases these are simple variables; integers or floats, but could be lists or arrays. In the case of passing arrays there is a hidden danger. Let’s consider a simple function:
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To use this function we pass two values, … Continue reading Arrays as function arguments
Audacity has a “Change Speed” effect, but it is only accurate to three decimal places. For greater accuracy a short Nyquist script can be used in the Nyquist Prompt effect. In this example the length of the selected audio was 599.999 seconds and I wanted to stretch it to 600 seconds duration.The durations may be … Continue reading Changing the speed and length very accurately
For a shorter display when hours [or hh:mm] are not required, set the ‘short’ parameter to 1. To display hh:mm:ss without milliseconds, set the second parameter [places] to 0. The ’round’ parameter can be set to round up, round down or round to the closest whole number of seconds. For full details of all options, … Continue reading Display time as hh:mm:ss
A common problem for people that are new to Nyquist is how to modify audio samples, for example, to set certain sample values to zero (silence). The temptation may be to read the audio sample by sample and modify them as necessary. In the vast majority of cases this is NOT the best approach as … Continue reading Silence part of an audio track (part 1)
This code snippet use SND-COMPOSE to create a vibrato effect
The basic detection method is just one short line of code: What this does is to fetch consecutive samples from the sound *track* until a sample is returned with a non-zero value. A word of caution, SND-FETCH is destructive to the audio data. If *track* will be required later in the code, use SND-COPY to … Continue reading How to detect a sound in just a few lines of code
To clip a waveform we can just use: (clip sound amplitude)
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To work round this problem we can create a sim function that works with multi-channel sound.
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Here we look at conditioning the recorded square wave to make it more “square” using a simple Nyquist script…. We can then modulate this with a high frequency carrier wave which could then be used to drive an IR transmitter from a computer sound card […]