Classic Computer Magazine Archive COMPUTE! ISSUE 148 / JANUARY 1993 / PAGE S15

How to choose and use a clip art conversion package. (Compute's Getting Started with Fonts & Clip Art)
by William Harrel

No matter how carefully you choose a clip art format, you can still run into an occasional program that doesn't support it. Fortunately, there are a number of ways to convert graphics from one format to another. They include the Windows Clipboard, using your graphics application's import/export filters, bitmapped tracing, and conversion utilities. The option you should use depends on the kind of conversion you need, and how often you convert files.

Depending on the complexity of the image, you can often open the file in a Windows application, copy the image to the Clipboard, and then paste it into another application. Remember that this method turns the image into a metafile--some of its quality (especially EPS graphics) could be lost, such as its ability to print at high resolutions.

Another option, assuming both applications support it, is to use Windows' Object Linking and Embedding (OLE) to place the image. This method allows you to edit the graphic with a graphics program, while the image remains embedded in the original program. This method maintains whatever artistic and resolution capabilities the server application is capable of.

To use OLE, instead of Paste, choose Paste Special from the edit menu. You're given a list of paste options, including embedding the image as an object linked to the server application. In other words, if you copied the image in CorelDRAW, one of the options in the Paste Special dialog box would be CorelDRAW Graphic Object. Double click on that option and the graphic file links to CorelDRAW.

Yet another option is to use your paint or draw program to convert the image. Some graphics programs, such as CorelDRAW and Professional Draw, have several import/export filters--one for almost every graphics type. This is simply a matter of importing the image in one format and then exporting it to another. In most cases, this works well enough, unless the image is complex. I've run into trouble exporting vector images with text to bitmapped formats.

Colors can often change during a conversion. Once or twice I've had entire objects drop out of an image, or sometimes, backgrounds have been left out.

You can anticipate some of these problems by reading the import/export notes some applications include in their documentation. CorelDRAW has extensive import/export technical notes in its Help system, under Reference.

Calling in a Specialist

If all else fails, you can buy a graphics conversion program, such as HiJaak or WinGIF. HiJaak, for example, converts files between about 50 different graphics types, supports several variations of TIF files, and even lets you choose the right CGM format based on the target application.

With HiJaak for Windows, conversions are menu driven. You can even do batch conversions (several files at the same time). And the program converts bitmapped graphics to editable EPS files, which is somewhat amazing.

While these programs work reasonably well, they're not foolproof. Certain graphics formats support some artistic qualities better than others. While a sophisticated conversion program can try to compensate for the differences in formats, it can't force a graphics format to assume qualities it doesn't support. You can't, for example, convert an EPS file to PCX and expect it to maintain the EPS file's ability to print at any resolution, or continue to support Type 1 fonts. But you can convert a PCX file to EPS format. The new EPS file will then print at the resolution of the output device. It will not, however, convert text in the PCX file to editable Type 1 fonts.

File conversions should be used primarily for compatibility. Usually, you gain nothing by converting graphics for other reasons, except, perhaps, converting a file that doesn't support CMYK color separations into one that does.

Some desktop publishing applications can separate full-color TIF files, for example, but not BMP graphics. In this case, the file must be converted. Another example is book publishers who use Ventura Publisher. It can save time during layout to converting graphics to Ventura's native GEM format.

Another file conversion option is bitmapped tracing with a tracing utility. Most draw programs come with tracing utilities, such as CorelDRAW's CorelTRACE. The best I've seen for maintaining quality and image integrity is Adobe's Streamline, which comes with Adobe Illustrator, but is also available separately.

What these utilities do is draw outlines, or bezier curves, around objects in the bitmapped image. You can then import the outline into your draw application as a vector drawing. Some of these utilities, such as Streamline, even maintain gray scale and colors.

In most cases, if your application supports the native format of your clip art, you'll have the best luck using it as is.