It is not obvious that the same limitation applies to the interlacing procedure that I have been promoting, but I am certainly suspicious, and the possibility deserves inspection. Figure 20 shows a narrow-banded signal that is properly interpolated, giving an impressive result. It is doubtful that an observant human could have done as well. On further study of Figure 20 I realized that it was not a stringent enough test. The signals obviously contain zero frequency, so they are not narrow-band in the sense of containing less than an octave.
Much seismic data is narrow-band.
I have noticed that aspects of these programs are fragile. We could continue to study the limitations of these programs. That program is fundamentally nonlinear and so somewhat risky, but it offers us the opportunity to drop the idea of interlacing the filter. Associated with interlacing is also a nagging doubt about plane waves that are imperfectly predictable from one channel to the next. When such data is interlaced, the PE filter really should change to account for the interlacing.