You can use a Decal with a rendering package, or you can use your image to generate a custom appearance. I don't do either of these, so you will have to hope that someone else answers with more details. You could try a search using "decal" or "appearance" and see what comes up in the forums or in SolidWorks Help.
I'd use the decal appearance mode for that. It's tricky at first to set them up.
I usually drag the default "DECAL" decal onto my part, then browse for my image.
Here's an example of a rectangular clip art decal on the surface of a sphere:
To adjust the position, you can drag the handles in the view, or use the Mapping options of the decal.
I've also saved my art as a decal in a unique folder as well, so it's always ready to use directly.
A great feature decals are, especially when you can put the client's logo on a photorealistic rendering. All they see is dollar signs!
If you need an external image editing software to clean up the image your planning on using as a decal, you might try the free GIMP image editing program. Paint or Photoshop might work for you also.
Hi Lam Yin,
If you want to merge an image onto the suface, I suggest that you should try a relevant image merging tool to see this target can be realized or not. I usually use multi-page TIFF merging and splitting tool to combine two or more TIFF files into a single new one. This image merging plugin also suits for othe commonly used raster and vector image formats.