MP3
During encoding, 576 time-domain samples are taken and are transformed to 576 frequency-domain samples.[clarification needed] If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)
When are 192 samples taken instead of 576?
there is a transient
[clarification needed] If there is a transient, 192 samples are taken instead of 576.
192 samples