1.[ToDo (c)] What does vector s reflected about t mean?

Answer: See slide 10 for photostereo. Note that s is R and t is N. You need to calculate L as your output.

2. [ToDo (f)] What items do go into the M matrix and the v vector for computing the Depths?

Answer:

Let me give you an example.
You want to use the following two equations to get z(i+1,j) z(i,j) z(i,j+1)
given nx,ny and nz.

We'd like to get z by solving Mz=v

Here are the corresponding M, z and v for the above two equations.

z=[z(i+1,j)

    z(i,j)

    z(i,j+1)]

M=[nz -nz 0

      0   -nz nz]

v=[-nx

    -ny]

3. [ToDo (f)] How do M matrix and the v vector for computing the Depths?

n=0;

For j=0 to height

For i=0 to width

If (pixel(i,j) is valid) {

If (pixel (i+1,j) is valid) {

//add horizontal normal constraint

//M(n,zind.Pixel(i,j,0))=?

//M(n,zind.Pixel(i+1,j,0)=?

n++;

}

If (pixel (i,j+1) is valid) {

//add vertical normal constraint

//M(n,zind.Pixel(i,j,0))=?

//M(n,zind.Pixel(i,j+1,0)=?

n++;

}

}

In makeMmatrix and makeVvector, we examine pixels in row-major order.

For example, (0,0),(0,1),...,(0,w),…,(h,w) where h and w are the height and width of an image.

We use pixvalid(zind,i,j) to check if pixel (i,j) is valid where i is the column and j is the row for this pixel.

Given a pixel (i,j) which is valid, we first add horizontal normal constraint if pixel (i+1,j) is valid.

M(n,zind.Pixel(i,j,0))=?;

M(n,zind.Pixel(i+1,j,0))=?

n++;

Then, you consider to add vertical normal constraint if pixel (i,j+1) is valid.

M(n,zind.Pixel(i,j,0))=?;

M(n,zind.Pixel(i,j+1,0))=?

n++;