Tidsstäckning

Tidsstäckning is a Swedish term that translates to "time stretching" or "time dilation" in English, commonly encountered in the context of audio processing. It refers to the process of altering the duration of an audio signal without changing its pitch. This can be achieved through various algorithms, with the most common relying on techniques like the phase vocoder or granular synthesis.

In audio editing software, time stretching is a fundamental tool for manipulating recorded sound. Musicians and sound engineers use it to correct timing errors, adjust the tempo of a piece of music, or create unique sonic textures. For instance, a slow melody could be sped up to match a faster tempo, or a drum loop could be elongated to create a more spacious feel, all while maintaining the original note frequencies.

The effectiveness of time stretching can vary depending on the complexity of the audio material and the algorithm employed. Simple waveforms or monophonic sounds are generally easier to stretch accurately, with minimal audible artifacts. However, complex polyphonic music or speech can present challenges, potentially leading to undesirable effects like "warbling," "smearing," or the introduction of unwanted resonances. Advanced algorithms aim to mitigate these artifacts by analyzing and reconstructing the audio signal in smaller segments, preserving transient details and spectral information as effectively as possible.