Changes between Version 13 and Version 14 of Tutorial/AdvancedParticleImagingVelocimetry2

Timestamp:

Aug 28, 2013, 12:29:18 PM (11 years ago)

Author:

sommeria

Comment:

--

Tutorial/AdvancedParticleImagingVelocimetry2

@@ -3 +3 @@
 
 = calibration =
-mark the four box corners with the mouse. We find ....
-The corresponding physical coordinates are known to be (0,0),(58.8,0),(58.8,55.1),(0,55.1), with an origin (0,0) taken at the lower left. Introduce those in the table ![ListCoord]. This can be conveniently done by copy paste of the Matlab vector x=[0 58.8 58.8 0] in the upper line of the x column, and y=[0 0 55.1 55.1] in the y column (use carriage return to validate the input).
+Mark the four box corners with the mouse. We find the coordinates of the four calibration points in pixels.
+
+(X,Y)=(80.3, 81.6),(982.3, 86.1),(978.9, 937.386),(71.2, 929.5).
+
+The corresponding physical coordinates are known to be 
+
+(x,y)=(0,0),(58.8,0),(58.8,55.1),(0,55.1), with an origin (0,0) taken at the lower left (and z=0). 
+
+Introduce those in the table ![ListCoord]. This can be conveniently done by copy paste of the Matlab vector x=[0 58.8 58.8 0] in the upper line of the x column, and y=[0 0 55.1 55.1] in the y column (use carriage return to validate the input).
 Then apply rescale. we observe that the figre is slightly rotated.
 We then apply linear which allows for rotation. The precison is improved.