from rsf.proj import *

bias = 128

def grey(title,transp='n',bias=bias):
    return '''
    sfgrey title="%s" transp=%s bias=%g clip=100
    screenht=10 screenwd=10 crowd2=0.85 crowd1=0.8
    label1= label2= 
    ''' % (title,transp,bias)

min = -50
max = 50

def graph(title=''):
    return '''
    sfgraph min2=%f max2=%f title=%s titlesz=14
    screenratio=.75
    ''' % (min,max,title)

# fetch the data from the data server
Fetch('lena.img','imgs')
Flow('lena','lena.img',
     '''
     echo n1=512 n2=513 in=$SOURCE
     data_format=native_uchar |
     sfdd type=float | sfwindow f2=1 
     ''',stdin=0)

# add noise 
Flow('nlena','lena','sfnoise seed=2006 var=1400')

# plots and FX spectra
titles = {'lena':'Lena',
          'nlena':'Noisy Lena'}
for name in titles.keys():
    Plot(name,grey(titles[name]) )
    cftitle = titles[name]+' in FX domain'
    Flow('fx'+name,name,'sfspectra')
    Plot('fx'+name,grey(cftitle,'y',100))

# display 2x2 figs
Result('panel1','lena nlena fxlena fxnlena','TwoRows',
       vppen='xsize=10 ysize=10')

# denoising using low-pass filtering
Flow('lplena','nlena','sfbandpass fhi=.075')
Plot('lplena',grey('Noisy Lena LP filtered'))

# thresholding
lg = 100.
thr = lg/6.
Flow('range',None,'sfmath n1=%d output="x1-%f" ' %(lg,lg/2))
Flow('thr',None,
     'sfmath n1=%d n2=2 output="(2*x2-1)*%f" ' %(lg,thr))

Plot('range',graph('Data with threshold level') )
Plot('thr',graph()+' dash=1')
Plot('data','range thr','Overlay')

Flow('hdata','range','sfthr thr=%f mode=hard' %thr)
Plot('hdata',graph('Thresholded data') )
Result('hthr','data hdata','SideBySideAniso')

# 2-D FFT
fft2 = 'sffft1 sym=y | sffft3 sym=y'
Flow('fnlena','nlena',fft2)

# denoising using thresholding in the Fourier domain
fthr = float(ARGUMENTS.get('fthr', 70))
Flow('fthrlena','fnlena','sfthr thr=%f mode="hard"' % fthr)

# 2-D inverse FFT
ifft2 = 'sffft3 sym=y inv=y | sffft1 sym=y inv=y '
Flow('thrlena','fthrlena',ifft2)
Plot('thrlena',grey('Thresholding in the Fourier domain') )

# combine figures 
Result('panel2','lplena thrlena','SideBySideIso',
       vppen='xsize=10 ysize=10')

End()