Converting Bitmap to SVG with Illustrator

Question

Hi,
Totally new to use Illustrator. Would be nice if I can do the folowing with Illustrator Cs4.
I downloded trail verion (have no money really -).
I would like to convert bitmap to svg tiny for mobile device. It looks if I save it as SVG tiny it can do it. But problem is with transparency.
Let's say I have a circle image  in bitmap and if I save it as svg and use it in mobile application then the 4 corners are visible as square (as seen as white in my case). Any idea how can I make it transparent?
br,
Mahbub

Answer 1

Mahbub,
This is what a Helpfile (old one) says about the SVG format in a format comparison:
Traditional image formats--GIF, JPEG, and PNG--are bitmap formats that describe  images, using a grid of pixels. The resulting files tend to be bulky, limited to  a single (often low) resolution, and consume large amounts of bandwidth on the  Web. SVG, or Scalable Vector Graphics, on the other hand, is a vector format  that describes images as shapes, paths, text, and filter effects. The resulting  files are compact and provide high-quality graphics on the Web, in print, and  even on resource-constrained, handheld devices. Users can magnify their view of  an SVG image on-screen without sacrificing sharpness, detail, or clarity. In  addition, SVG provides superior support for text and colors, which ensures that  users will see images as they appear on your Illustrator artboard.
Illy, like SVG, is basically about vector, not raster/bitmap.
All this means that you need vector artwork in order to enable scaling, which you may not need.
But the corner issue seems to be related to bitmap images basically being rectangular. Some bitmap formats, such as PNG and GIF can have transparent parts, such as the areas forming the outside parts that should be invisible, such as  corner parts at roundings. You may seemingly cut parts of bitmap image shapes in Illy (by making parts transparent), using Clipping Masks; there may be easier ways in CS4. Some may suggest your using Photoshop for such tasks.