Signal cropping is equivalent to applying a rectangular window

Evidence

Some frequently applied window functions are the Hamming, Hann (a.k.a. Hanning window), Blackman, and Kaiser windows (Mitra and Kaiser, 1993). Note that cropping a span from a signal and zeroing elsewhere corresponds to using a rectangular window. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 386

Categorization

• DEFINE: Clarifies that simply cropping a signal segment is itself a windowing operation, with specific spectral consequences.