Mark Levinson N 51 - Manual (Page 54)

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Setup Menu Mark Levinson
Deinterlacing
Standard DVDs are normally encoded as either interlaced 60Hz (i.e.
480i@60Hz for NTSC) or interlaced 50Hz (i.e. 576i@50Hz for PAL).
Interlaced video can display many annoying video artifacts, such as
flickering, combing (referred to as “feathering”), etc. To lessen the
video artifacts associated with interlaced video, the Nº51 offers all
the well-known deinterlacing categories. Briefly, deinterlacing is
used to create 50 frames/sec. from 50 fields for PAL or 60 frames/sec.
from 60 fields for NTSC in each second.
Parameter setting Description
Bob This method applies spatial interpolation to every
field to create a whole frame. The advantage of
this method is that there is no feathering artifact
for moving objects. The two major unavoidable
artifacts of this method are thin line flickering and
loss of picture details due to interpolation. The
Nº51 applies an improved interpolation method
to minimize the second artifact.
Weave This method applies temporal interpolation of two
consecutive fields, which are merged (“woven”)
into one frame. It is suitable for still images with
full resolution but results in saw edges and feath-
ering effects on moving objects.
Motion Adaptive This method applies the Bob method for moving
objects and the weave method for still areas. In
other words, for one created frame, some parts are
generated from field interpolation, others are from
weaving. This method can produce advantages
from both the Bob and the Weave method.
Motion
Compensat. This is the most advanced method using state-of-
the-art technology. For moving objects, in
addition to interpolating the data from each field
into frames, this method estimates the motion
and applies both temporal and spatial interpo-
lation methods. Compared to the motion adaptive
method, Motion Compensat. achieves improved
picture detail and a much smoother-looking
picture is achieved.
Motion
Compensat. + Sometimes motion estimation using the motion
compensation method can produce “Halo”-
effects, which appear as contours around edges of
moving objects. Motion Compensat.+ automati-
cally switches between pure motion adaptive and
pure motion compensation to always provide an
optimized solution. In addition, the Nº51 offers a
threshold level adjustment to ensure optimum
performance. Setting the threshold level to a lower
number will make Motion Compensat.+ more like
pure Motion Adaptive, while setting it to a higher
number will make Motion Compensat.+ more like
pure Motion Compensat.