Modifying frame gains in overlap-add processing reveals previously cancelled aliasing artifacts as audible distortion.

Evidence

Consider Figure 15.5, where the upper graph shows the original signal and the lower one shows four subsequent time frames reproduced. Note that the second and third frames have a triangular component near sample 1024 that does not correspond to the original signal and is cancelled out when the frames are overlap-added. If the level of the second or third frame is modified in the processing of frequency-domain signals, the triangular component of the second frame produces a clearly audible aliasing component. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 2091

Categorization

• QUESTION: What error-masking or gain-adaptation strategies in real codecs (like MP3 or AAC) account for these hidden aliasing components during loudness or EQ adjustments?