This Tutorial is made with Inventor 2012 pro. The same steps apply with Inventor 2011. I am not sure about earlier versions.
We need to save our image in .bmp (bitmap) format in the sample folder of Inventor. For Windows 7 the default directory is:
C :\ Users \ Public \ Documents \ Autodesk \ Inventor 2012 \ Textures \ surfaces
Next we open Inventor (if we haven't done so already) and create a new part file or open a part file we already have.
We go to colour styles
we choose "new"
We give a name to our new style
Then we click in the "use texture image" box
A new window appears with images to choose from
If step 1 was made correctly we should be able to find our image in the library.
We can adjust the scale and the rotation of the texture. We can also select how our style will look if we switch on realistic appearance. To do so click on "Open the material Library" button at the bottom of the window.
Select an image from the library. You can adjust scale and rotation in this case also.
If you are done click "Save" and "Done"
In the drop down menu select the colour style you have created.
And you are ready!
Also a rendered version of our part.