We derive the signal amplitude by detecting a robust positive and negative envelope of the color-error signal.
A note on a negative envelope absolutely blew my mind.
In this case, the techniques include handwriting analysis of the negatives' envelopes; meteorological comparisons of one of Adams's photographs with a similar negative in Norsigian's collection; and consultation with Robert Moeller, the former curator of the Boston Museum of Fine Arts, and the large-format photographer Patrick Alt.
The special architecture of Gram-negative envelope screens the enter of molecules and strongly control the diffusion of toxic molecules including antibiotics, detergents, etc [6], [7], [31].
A contrasting interpretation, presented by Mira, et al. [92], is that Fusobacterium represents a genus with a Clostridial metabolic apparatus that has obtained a gram-negative envelope from the Proteobacteria.
Amongst bacteria, it is predominantly found in bacteria with Gram-negative envelope: the majority of proteobacterial lineages (including acidobacteria), cyanobacteria, Aquifex and some nitrospirae, which contain one or more proteins with AMIN domains.
The negibacterial envelope ultrastructure of Selenobacteria such as the heterotrophic Selenomonas, Sporomusa, and the phototrophic Heliobacteria has been known for some time, which led me to exclude them from Posibacteria and to group them in the phylum Eurybacteria [ 69] with Fusobacterium, which also has a Gram-negative envelope, but unlike the others lacks flagella.
This is strongly indicated by the fact that Selenobacteria (phylum Eurybacteria: Tables 1, 2; Fig. 7) have a fairly typical Gram-negative envelope with an outer membrane and thin sacculus [ 64], yet have endospores that are indistinguishable from those of Endobacteria [ 65- 67].
The output signal with constant magnitude is obtained by dividing the differential input signal to the difference between the positive and negative detected envelopes.
Another unsurprising observation that can be made from Figure 3 is that the non-negative Hilbert envelopes are turned into signals that have both positive and negative amplitude values.
