progress in findxtal.py

This commit is contained in:
2018-04-18 15:50:43 +02:00
parent c131b05194
commit 2465fc86c6

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@@ -12,50 +12,77 @@ implements an image alalyser for ESB MX
from scipy import fftpack, ndimage
import scipy.ndimage as ndi
import matplotlib.pyplot as plt
import matplotlib as mpl
import numpy as np
#plt.ion()
def ffttest():
for phi in np.arange(0.,180.,10.):
ffttest2(phi=phi)
plt.show()
pass
def ffttest2(phi=45.,frq=4.2,amp=1.,n=256.):
#find the main frequency and phase in 1-D
#plt.ion()
plt.figure(1)
d2r=np.pi/180.
n=16.
x=np.arange(n)
amp=1.
frq=4.5
phi=40.*d2r
y=amp*np.cos(phi+frq*x/n*2.*np.pi)
phi=phi*d2r
y=amp*np.cos(frq*x/n*2.*np.pi-phi)
plt.plot(x,y,'y')
#y[np.where(y<-.5)]=0
#y*=np.hamming(n)
y*=np.hanning(n)
w=np.hanning(n)
plt.plot(x,w,'y')
y*=w
#y*=1.-np.cos(x/(n-1.)*2.*np.pi)
#y=[1,-1,1,-1,1,-1,1,-1,1,-1,1,-1,1,-1,1,-1]
plt.ion()
plt.figure()
plt.stem(x,y)
fy=np.fft.fft(y)
fya=np.abs(fy)
plt.figure()
plt.figure(2)
plt.subplot(211)
plt.stem(x,fya)
plt.subplot(212)
plt.stem(x,np.angle(fy)/d2r)
print(np.angle(fy[frq])/d2r)
fya[0]=0
i=(fya.reshape(2,-1)[0,:]).argmax()
(vn,v0,vp)=fya[i-1:i+2]
frq2=i+(vn-vp)/(2.*(vp+vn-2*v0))
print('freq: %g phase %g'%(frq2,np.angle(fy[i])/d2r))
#TODO: THE PHASE CALCULATION IS NOT YET WORKING!!!
frq_=i+(vn-vp)/(2.*(vp+vn-2*v0))
print('freq: %g phase %g %g %g'%((frq_,)+tuple(np.angle(fy[i-1:i+2])/d2r)))
#y_inv=np.fft.fft(fy)
#plt.figure()
#plt.plot(x,np.abs(y_inv))
#PHASE CALCULATION
plt.figure(1)
y=np.zeros(x.shape)
z=np.zeros(x.shape)
for ii in (i,i-1,i+1):
y+=np.abs(fy[ii])/n*np.cos(ii*x/n*2.*np.pi+np.angle(fy[ii]))
z+=np.abs(fy[ii])/n*np.sin(ii*x/n*2.*np.pi+np.angle(fy[ii]))
y*=2 #double because of conjugate part
z*=2 #double because of conjugate part
plt.plot(x,y,'r')
amp_=fya[i-1:i+2].sum()/n*2.
t=int(n/2)-1
#->phase: find maximum or where the sin is 0
w=np.arccos(y[t]/amp_)
if(z[t]<0): w=-w
print('amplitude %g, value at middle (%d) cos->%g sin->%g -> acos %g deg'%(amp_,t,y[t],z[t],w/d2r))
#rot angle at middle x=127 =frq_*t/n*2.*np.pi-phi_=w '%(amp_,t,y[t],phi_/d2r))
phi_=frq_*t/n*2.*np.pi-w
y=amp_*np.cos(frq_*x/n*2.*np.pi-phi_)
print('y[%d] %g'%(t,y[t]))
plt.plot(x,y,'g')
pass
def findGrid(image,numPeak=2):
d2r=np.pi/180.
#image = ndimage.imread('/home/zamofing_t/Documents/prj/SwissFEL/epics_ioc_modules/ESB_MX/python/images/grid_20180409_115332.png', flatten=True) # flatten=True gives a greyscale image
s=image.shape
w1=np.hamming(s[0]).reshape((-1,1))
@@ -67,36 +94,83 @@ def findGrid(image,numPeak=2):
#plt.figure(num='hamming window*img')
#plt.imshow(image, interpolation="nearest")
fft2 = fftpack.fft2(image)
fft2 = np.fft.fft2(image)
fft2=np.fft.fftshift(fft2)
fa =abs(fft2)
fal =np.log(fa)
#img=fft3;
ofs=int(fal.min())
mx2=(image.shape[0]/2,image.shape[1]/2)
fal[mx2[0] - 1:mx2[0] + 2, mx2[1] - 1:mx2[1] + 2]=ofs
for i in range(numPeak*2):
mx=fal .argmax()
mx2=divmod(mx,fal .shape[1])
peakPos=(mx2[0] - image.shape[0] / 2, mx2[1] - image.shape[1] / 2)
peak=fal[mx2[0] - 1:mx2[0] + 2, mx2[1] - 1:mx2[1] + 2]
plt.figure(num='log of fft: hamming wnd*image')
hi=plt.imshow(fa, interpolation="nearest",norm=mpl.colors.LogNorm(vmin=.1, vmax=fa.max()))
#plt.xlim(s[1]/2-50, s[1]/2+50);plt.ylim(s[0]/2-50, s[0]/2+50)
ctr=np.array(image.shape,dtype=np.int16)/2
fa[ctr[0] - 1:ctr[0] + 2, ctr[1] - 1:ctr[1] + 2]=0 # set dc to 0
hi.set_data(fa)
gen = np.zeros(fft2.shape)
x=np.arange(s[1])/float(s[1])*2.*np.pi
y=np.arange(s[0])/float(s[0])*2.*np.pi
#x=np.linspace(0,2*np.pi,s[1],endpoint=False)
#y=np.linspace(0,2*np.pi,s[0],endpoint=False)
my=int(s[0]/2)
mx=int(s[1]/2)
xx, yy = np.meshgrid(x, y)
res=[] #list of tuples (freq_x,freq_y, phase)
for i in range(numPeak):
maxAmpIdx=fa.argmax()
maxAmpPos=np.array(divmod(maxAmpIdx,fa.shape[1]),dtype=np.int16)
peakPos=maxAmpPos-ctr
peak=fft2[maxAmpPos[0] - 1:maxAmpPos[0] + 2, maxAmpPos[1] - 1:maxAmpPos[1] + 2]
print(peakPos)
print(peak)
(vn, v0, vp)=fal[mx2[0], mx2[1] - 1:mx2[1] + 2]
frq1x=peakPos[1]+(vn-vp)/(2.*(vp+vn-2*v0))
(vn, v0, vp)=fal[mx2[0]-1:mx2[0]+2,mx2[1]]
frq1y=peakPos[0]+(vn-vp)/(2.*(vp+vn-2*v0))
print((frq1x,frq1y))
fal[mx2[0]-1:mx2[0]+2,mx2[1]-1:mx2[1]+2]=i+ofs
print(abs(peak))
(vn, v0, vp)=np.log(fa[maxAmpPos[0], maxAmpPos[1] - 1:maxAmpPos[1] + 2]) #using log for interpolation is more precise
freq_x=peakPos[1]+(vn-vp)/(2.*(vp+vn-2*v0))
(vn, v0, vp)=np.log(fa[maxAmpPos[0]-1:maxAmpPos[0]+2,maxAmpPos[1]])
freq_y=peakPos[0]+(vn-vp)/(2.*(vp+vn-2*v0))
#calculate phase
sumCos=0.
sumSin=0.
sumAmp=0.
n=np.prod(s)
for iy in (-1,0,1):#(0,):
for ix in (-1,0,1):
v=peak[iy+1,ix+1]
fx=peakPos[1]+ix
fy=peakPos[0]+iy
amp=np.abs(v)/n; ang=np.angle(v)
sumAmp+=amp
sumCos+=amp*np.cos(fx*x[mx] + fy*y[my] + ang)
sumSin+=amp*np.sin(fx*x[mx] + fy*y[my] + ang)
gen+=amp*np.cos(fx*xx + fy*yy + ang)
sumAmp*=2. #double because of conjugate part
sumCos*=2.
sumSin*=2.
#sumAmp=np.abs(peak).sum()/n*2 #double because of conjugate part
w=np.arccos(sumCos/sumAmp)
if sumSin<0: w=-w
phi_= freq_x*x[mx]+freq_y*y[my]-w
phi_%=(np.pi*2)
res.append((freq_x,freq_y,phi_))
fa[maxAmpPos[0]-1:maxAmpPos[0]+2,maxAmpPos[1]-1:maxAmpPos[1]+2]=0 # clear peak
maxAmpPos_=2*ctr-maxAmpPos
fa[maxAmpPos_[0]-1:maxAmpPos_[0]+2,maxAmpPos_[1]-1:maxAmpPos_[1]+2]=0 # clear conjugated peak
hi.set_data(fa)
gen*=2. # double because of conjugate part
for fx,fy,phase in res:
print('fx: %g fy: %g phase: %g deg'%(fx,fy,phase/d2r))
plt.figure(num='fft of hamming window*img')
plt.imshow(fal, interpolation="nearest")
plt.xlim(s[1]/2-50, s[1]/2+50)
plt.ylim(s[0]/2-50, s[0]/2+50)
plt.show()
plt.figure('image*wnd')
plt.imshow(image,interpolation="nearest")
plt.figure('reconstruct')
plt.imshow(gen,interpolation="nearest")
plt.figure()
x=range(s[1])
y=int(s[0]/2)-1
plt.plot(x,image[y,:],'r')
plt.plot(x,gen[y,:],'g')
pass
def findObj(image,objSize=150,tol=0,viz=0):
@@ -196,31 +270,43 @@ def findObj(image,objSize=150,tol=0,viz=0):
def genImg(shape,*args):
'''args is a list of tuples (freq_x,freq_y, phase) multiple args can be added'''
image=np.ndarray(shape)#,dtype=np.uint8)
x=np.linspace(0,2*np.pi,shape[1])
y=np.linspace(0,2*np.pi,shape[0])
x=np.linspace(0,2*np.pi,shape[1],endpoint=False)
y=np.linspace(0,2*np.pi,shape[0],endpoint=False)
#xx, yy = np.meshgrid(x, y, sparse=True)
xx, yy = np.meshgrid(x, y)
dc=0
for i,f in enumerate(args):
(freq_x, freq_y, phase)=f
if i==0:
image = np.cos(freq_x*xx + freq_y*yy + phase)
image = dc+np.cos(freq_x*xx + freq_y*yy - phase)
else:
image += np.cos(freq_x * xx + freq_y * yy + phase)
image += np.cos(freq_x * xx + freq_y * yy - phase)
plt.imshow(image, interpolation="nearest")
plt.show()
return image
if __name__ == '__main__':
#plt.ion()
#ffttest()
#image = ndimage.imread('/home/zamofing_t/Documents/prj/SwissFEL/epics_ioc_modules/ESB_MX/python/images/grid_20180409_115332.png')
image = ndimage.imread('/home/zamofing_t/Documents/prj/SwissFEL/epics_ioc_modules/ESB_MX/python/images/grid_20180409_115332.png')
#image = ndimage.imread('/home/zamofing_t/Documents/prj/SwissFEL/epics_ioc_modules/ESB_MX/python/images/grid_20180409_115332_45deg.png')
#image=-image
image=genImg((600,800),(9.5,.2,0))
#image=genImg((600,800),(9.5,.2,0),(.4,5.2,0))
image=-image
#image = ndimage.imread('/home/zamofing_t/Documents/prj/SwissFEL/epics_ioc_modules/ESB_MX/python/images/honeycomb.png')
d2r=np.pi/180.
#for phi in np.arange(0.,180.,10.):
# image = genImg((600, 800), (4.5, .2, phi*d2r))
# plt.show()
#image=genImg((600,800),(4.,1.0,10.*d2r))
#image=genImg((600,800),(4.5,.2,20.*d2r))
#findGrid(image,numPeak=1)
#image=genImg((600,800),(9.5,.2,20.*d2r),(.4,5.2,60.*d2r))
#image=genImg((600,800),(3.5,0.,0.*d2r),(0,5.,0.*d2r))
findGrid(image,numPeak=2)
#image=genImg((600,800),(9.5,.2,0),(.4,5.2,0),(4,8,0))
findGrid(image,numPeak=1)
#findObj(image,viz=1)
#findObj(image,viz=255)
#print(findObj(image))
plt.show()