nullnivå

Nullnivå is a term used in Swedish and Norwegian technical language to denote the zero reference level in a measurement or display. It serves as the baseline from which other values are measured or compared, and its exact meaning depends on the discipline and context.

In instrumentation and sensors, nullnivå often refers to the zero setting of a device—the condition under which the output is defined as zero. This requires calibration and can drift due to temperature, wear, or aging. The process is known as zeroing or taring.

In acoustics and audio engineering, nullnivå denotes the baseline or reference level of sound pressure or digital signal amplitude against which levels are reported. It commonly corresponds to a no-signal condition or the quietest practically detectable level, depending on the measurement system.

In imaging and vision systems, nullnivå can describe the baseline luminance value corresponding to zero light input, or the lowest measurable signal in sensor data. It is essential in determining contrast and dynamic range, and may require offset corrections in image processing.

In data communications and digital data, nullnivå may indicate the absence of a value or a placeholder used to signal "no data." In such contexts, software and hardware define a distinct null or zero that is not to be confused with a legitimate value.

Name and usage vary by language and field, but the core idea is a universal reference point for what counts as "nothing" or "zero" within a given system.