Assignment #1 Problem 2

[>flo<]

This is about pt. 6.

We are asked here to check whether the gradient magnitude exceeds a certain threshold.

Okay--that means we have to look at every pixel and compare the value to the chosen threshold.

However, we are asked to *not* use any for loops.

Well, how am I gonna look at any pixel in the image without a for loop? Is there any built-in matlab function that does this job for me?

Thanks for helping me out.

[>flo<]

To pt.5:

Is the gradient magnitude the square root of the summed 2nd derivatives or just the square root of the summed squares of the 1st derivatives?

ty

[Trigger]

Check out the documentation of rational operators. Especially the example: http://www.mathworks.com/access/helpdes ... ators.html

The gradient magnitude is the length of the gradient. Have a look at the definition of the gradient and you will know the answer: http://en.wikipedia.org/wiki/Gradient

HTH
Armin

[YMBY]

Zu deinen Fragen ein paar "schöne" Tipps:

1. es gibt den Matlabbefehl "gradient"
2. es gibt auch für Matrizen den Matlabbefehl ">"
3. die Magnitude des Gradienten ist die Länge dieses Vektors

=> Apropos: gibts das Übungsblatt inzwischen irgendwo online??

YMBY

[C.]

Es gibt ein paar sehr schöne Matlabbefehle, z. Bsp.:

1. [fX, fY] = gradient(pic)

Please use the filters from Problem 2.3 to generate the gradient images.

=> Apropos: gibts das Übungsblatt inzwischen irgendwo online??

Y

Have a look


Christian