Macromedia Flash 8 Bible

Maintaining Color Consistency

Flash can only use an RGB color space, meaning that it renders colors in an additive fashion — full red, green, and blue light added together produce white light. Whenever possible, you should use RGB color pickers in your preferred drawing application. If you're using Illustrator, specifying colors with the RGB color picker ensures that both copied-and-pasted objects and exported files will appear as you see them in the original workspace. If you use CMYK (cyan, magenta, yellow, and black), then you will notice color shifts when the artwork is imported into Flash. Fireworks is an RGB graphics environment, so your artwork will be Flash and Web-friendly.

Tracing to Convert Rasters to Vectors

A handful of applications, including Flash and FreeHand, let you trace raster artwork to create a vector "drawing." Adobe's stand-alone product for tracing images, Streamline, has been discontinued in favor of the more advanced tracing tools now integrated as the Live Trace feature in Illustrator CS2.

With any tracing application, keep these points in mind:

• Higher resolution images always yield better "traced" vector artwork. With more pixels to define edges, the application can better detect shapes.

• Images with many colors, subtle gradients, or very complex patterns may need to be simplified before they can be traced and effectively converted into vector files.

• Sharper images (such as clearly focused images) and higher contrast images produce better traced artwork. Applying Photoshop or Fireworks filters to reduce the complexity of a photographic image can make it easier to trace.

• One-color images or scans, like those of hand-drawn sketches with pencil or ink, produce the best traced results.

With all of the software and tool options available, it can be difficult to keep track of all the variables. The most important thing to decide is how you want your final artwork to look. For example, if you want a minimal silhouetted vector look, then it may actually be better to create a clipping path from the bitmap and fill it with solid color manually than to use an autotrace tool. On the other hand, if you are trying to maintain detail in an image and your goal is simply to reduce your file size, it may be best to import an optimized bitmap directly into Flash (where you can then apply the Break apart command and erase any unnecessary parts of the image).

The two traps that you want to avoid in production are bloated file sizes and needless quality loss. There are certainly times when you will have to compromise on image size or resolution in order to keep your Flash movies streamlined, but don't make the mistake of assuming that the worse the image looks, the smaller your file will be — this is not always the case.

Figure 37-1 compares the same bitmap image in a series of different workflow options. As you can quickly see, the differences in file size do not always have the same relationship to image quality as you might expect.

Figure 37-1: Even when the final image quality is similar, the file sizes that are achieved with different workflow options can vary widely.

In our production testing overall, Flash proves to be the first choice for achieving high image quality and small file sizes with traced or optimized bitmaps. The lesson we've learned is that unless we need a special effect that can't be created directly in Flash, it's best to import high-quality images (scaled appropriately for the movie size) directly to Flash and use the native Flash authoring tools to modify the image if needed.