def HHIPreFilter(config={}):
"""HHI pre-interlace filter.
A widely used prefilter to prevent line twitter when converting
sequential images to interlace.
Coefficients taken from: 'Specification of a Generic Format
Converter', S. Pigeon, L. Vandendorpe, L. Cuvelier and B. Maison,
CEC RACE/HAMLET Deliverable no R2110/WP2/DS/S/006/b1, September
1995. http://www.stephanepigeon.com/Docs/deliv2.pdf
"""
fil = numpy.array(
[-4, 8, 25, -123, 230, 728, 230, -123, 25, 8, -4],
dtype=numpy.float32).reshape((-1, 1, 1)) / numpy.float32(1000)
resize = Resize(config=config)
out_frame = Frame()
out_frame.data = fil
out_frame.type = 'fil'
audit = out_frame.metadata.get('audit')
audit += 'data = HHI pre-interlace filter\n'
out_frame.metadata.set('audit', audit)
resize.filter(out_frame)
return resize
def __init__(self, config={}, **kwds):
super(PostFilterUV,
self).__init__(resize=Resize(),
filgen=FilterGenerator(xaperture=12, xcut=22),
linkages={
('self', 'input'): [('resize', 'input')],
('filgen', 'output'): [('resize', 'filter')],
('resize', 'output'): [('self', 'output')],
},
config=config,
**kwds)
def __init__(self, config={}, **kwds):
# 4fsc = 922 active samples/line, Rec 601 = 702 active samples/line
xup, xdown = 351, 461
super(From4Fsc, self).__init__(
resize = Resize(xup=xup, xdown=xdown),
filgen = FilterGenerator(xup=xup, xdown=xdown, xaperture=12),
linkages = {
('self', 'input') : [('resize', 'input')],
('filgen', 'output') : [('resize', 'filter')],
('resize', 'output') : [('self', 'output')],
},
config=config, **kwds)
def __init__(self, config={}, **kwds):
super(PostFilterPAL, self).__init__(
resize = Resize(),
fildes = FilterDesign(
frequency='0.0, 0.307, 0.317, 0.346, 0.356, 0.5',
gain=' 1.0, 1.0, 1.0, 0.0, 0.0, 0.0',
weight=' 1.0, 1.0, 0.0, 0.0, 1.0, 1.0',
aperture=17,
),
linkages = {
('self', 'input') : [('resize', 'input')],
('fildes', 'filter') : [('resize', 'filter')],
('resize', 'output') : [('self', 'output')],
},
config=config, **kwds)
def __init__(self, config={}, **kwds):
super(PostFilterY, self).__init__(
resize=Resize(),
fildes=FilterDesign(
frequency=
'0.0, 0.215, 0.22, 0.23, 0.25, 0.27, 0.28, 0.285, 0.5',
gain=
' 1.0, 1.0, 0.8, 0.0, 0.0, 0.0, 0.8, 1.0, 1.0',
weight=
' 0.6, 0.6, 0.6, 1.0, 1.0, 1.0, 0.3, 0.3, 0.3',
aperture=11,
),
linkages={
('self', 'input'): [('resize', 'input')],
('fildes', 'filter'): [('resize', 'filter')],
('fildes', 'response'): [('self', 'response')],
('resize', 'output'): [('self', 'output')],
},
config=config,
**kwds)