Editing Lua audio add-on API (section)

== Audio block ==
Audio samples are normally in the range -1 to 1. Indices are zero-based, and values written by an add-on must be finite.

{| class="wikitable"
! Method !! Effect or result
|-
| <code>audio:size()</code> || Number of samples in the block.
|-
| <code>audio:sampleRate()</code> || Sample rate in hertz.
|-
| <code>audio:sessionTime()</code> || Time in seconds at the start of the block.
|-
| <code>audio:samplePosition()</code> || Absolute sample position at the start of the block.
|-
| <code>audio:get(index)</code> || Reads one sample.
|-
| <code>audio:set(index, value)</code> || Replaces one sample.
|-
| <code>audio:map(function(sample, index, time) ... end)</code> || Replaces every sample with the callback result.
|-
| <code>audio:gain(amount)</code> || Applies a constant linear gain.
|-
| <code>audio:limit(peak)</code> || Limits samples to the symmetric positive peak.
|-
| <code>audio:mixTone(frequencyHz, level)</code> || Adds a sine tone and reserves headroom.
|-
| <code>audio:mixTone(frequencyHz, level, reserveHeadroom)</code> || Adds a tone with optional headroom reservation.
|-
| <code>audio:fill(value)</code> || Replaces the block with a constant value.
|-
| <code>audio:peak()</code> || Absolute peak of the current block.
|-
| <code>audio:rms()</code> || Root mean square level of the current block.
|}

The tone frequency must be at least zero and below half the sample rate. The peak supplied to <code>limit</code> must be positive.