Tutorial Flash - Tracing Bitmaps

Bitmaps store picture data in raster format. This means that information of each pixel is stored which results in large file size. Flash allows us to import bitmap images and convert them to vector format thus reducing the file size.

I was once a Doors fan
Here is Jim Morrison. This image is the .jpg format 4486 bytes in size.

To convert this bitmap image we will use the Trace Bitmap feature found under the Modify menu.
Click File - Import and migrate to the directory that stores the image. Select the file and click Open.
The imported image will be placed at the center of the stage.
If the Symbol library is not open, display it by clicking Window - Library. You'll notice that Flash has already added the image is the symbol listing.
Click Modify - Trace Bitmap. The pop up window has a dazzaling array of options. These help you to optimize the tracing. Remember, there is always a tradeoff involved when tracing bitmaps. The key is to experiment with various values till you get the desired result.

Color Threshold
It specifies the number of colors to be used for tracing the bitmap. Lower number of colors will result in simpler bitmaps thus, lower file size. The value can range from 1 to 256.

Minimum Area
The traced bitmap will have patches of plain color. The minimum area of these patches can be supplied with this option. Note that larger values for area will lower file size however, it shall also decrease the clarity.

Curve Fit
The options in this drop down menu are Pixel, Very Tight, Tight, Normal, Smooth and Very Smooth. They set the number of curves in the drawing and the more the number of curves the larger the file size. Evidently, Pixel value will result in greater number of curves while Very Smooth results in a smaller number.

Corner Threshold
The choices are Many Corners, Normal and Few Corners. The lesser the number of corners, the lower the images size.

Using the following values, Morrison's image resembles: