pathfinder - Why is Illustrator's minus front not working?

I have some white lines (converted to path) on top of my star shape (rasterized) as shown in the picture. I am trying to "delete" the white lines from the shape so the shape gaps can be seen in transparent if that makes sense. The rectangle on top right shows what I am trying to achieve.

I tried to select both the star and the lines path and use Minus Front from Pathfinder and although there seems to accept the command nothing happens. What am I doing wrong? Can this also be achieved using clipping masks?

Answer

Illustrator can't do Pathfinder effects on rasterised files it has placed.

To achieve this effect, you will indeed have to use a clipping mask:

1. draw a circle snugly around your star;


2. unite all your white lines to a single shape;


3. subtract the lines shape from the circle using the Pathfinder;



4. ungroup the result...


5. ...and make it a compound path: Object > Compound Path > Make or Ctrl / Cmd+8 or right-click > Make Compound Path;


6. remove fill and stroke from the compound path;


7. select both the compound path and your star;


8. choose Object > Clipping Mask > Make or right-click > Make Clipping Mask.