Stylus shape stats (width/depth ratio)

Summary

* Histogram of the ratio of groove width to groove depth is shown in figure above.
* The result showing that the width/depth ratio is extremely stable for this piece of data.

Detail

* The data used are 3223 FOVs of the stereo sinewave (about 10 sec).
* In the 10-bin histogram (Matlab default), the most dominant bin is the ratio 0.290, with a percentage of 99.99987%, among 5497858 instances (azimuthal increments).
* In the 20-bin histogram, the most dominant bin is 0.126, with a percentage of 99.9999%

Stereo decoding

Left channel = delta(r, left) - delta(depth)
(left sidewall 45degree upwards)

Right channel = delta(r, right) + delta(depth)
(right sidewall 45degree downwards)

Imp

• vr_in, vr_out, vz_in, vz_out
  
• stylus shape: v_width -> v_depth
• ? fit(vr_in), fit(vr_out), fit(v_depth)
• ? diff(vr_in), diff(vr_out), diff(v_depth)
• vr_diff_in - vd_diff, vr_diff_out + vd_diff

Overlap merge: master slave

Problem

• I'm afraid that slave may break because master FOV chain may skip some slaves because it does 1v1 FOV comparison
• when slave FOVs missed out and shifts applied to other FOVs, gaps appear.

Idea

• before matching, create master/slave/bottom groups, ensure each slave has a master, each master has a slave
• match every master that has a in-FOV, same-CC slave, match
  

imp

1. 3 runs, for each master, find slave, bottom, of same FOV.cc
1. keep a vb_has_group for master, slave, bottom
2. after 1st run, vb_has_group_master = [true, ......false, true.....], vb_has_group_slave = [true, ......true, true....], vb_has_group_bottom = [true, ......true]
   
3. in 2nd run, unpaired master(k), finds in slave[k-1, k, k+1] possible slave,
   
4. in 3nd run, same for slave(k), finds in master[k-1, k, k+1] ...
   

scribefire

hello

Got it. Vector sum

The sidewall movement can be seen the vector sum of the horizontal and vertical movement.
But it's still not directly depicted by the width and depth change, e.g. pure lateral modulation has constant width.

Still don't understand the width/depth based stereo decoding

As far as I know, if the stereo cutter moves only vertically to produce out-of-phase signal,
the linear combination of (W+H) or (W-H) won't be able to give an out-of-phase signal.

To my knowledge, only the displacement of sidewall can explain this case.

Am I missing something?

Question to ask ich

1. Review of old work

• Optics: explaining the terms? Optical flow?
  
• Hardware: resolution, photos? illuminations
  
• Software: preprocessing, groove extraction, which part of groove is undulation.
  
• Common approach: RIAA EQ.
  
• Error introduced: Stotzer's blur
  
• Result: data amount, time cost
  
• Quality
• Fundamental difference with our approach
  

2. My workflow

• Optics: WLI
  
• Hardware:
  
• Software: alignment, polar/tertiary, preprocessing (detach/reattach), unwrapping, center correction, stereo.
  
• Common: edge detection, RIAA
  
• unique
• Error introduced: warp, center offset
  
• Result:
  
• Quality
  

3. Result