This question comes up quite frequently, so I've pulled together the following resources to address the most common image conversion situations.
The first thing to understand is that there are many, many image formats and hundreds of software programs capable of converting images. Many of these image formats are native to one specific graphic application and are not offered as an export option in other software. If you receive an image file from someone and you're not familiar with it, I've compiled links to a number of online databanks where you can research file format extensions.
Also, be aware that not all image formats are compatible with one another. In general, you can almost always convert between bitmap formats and from vector to bitmap. This is as simple as opening the image in just about any image editor (or image viewer) and choosing the Save As command. You probably already have software that you can use to do this. For instance, the Microsoft Paint program that comes with Windows can convert between BMP, JPEG, and GIF formats.
If you need to convert between other formats, you can check into the image converters, image editors and image viewers that are listed on this site. There are plenty of freeware and shareware products to choose from, but be sure to check the features list and supported import and export formats to find one that meets your needs. If you need a push in the right direction, try XnView or IrfanView, two free image viewers which both support hundreds of file types. If you still need help, try asking in the discussion forum where you're likely to get suggestions from other members.
It's not uncommon for new scanner owners to save an image in their scanning software's default format. If someone has sent you a file and you have difficulty identifying the format or finding a software program that supports it, you may need to go back to whoever sent you the file and ask them to save it in a universally accepted standard format, such as GIF or JPEG. For more information on saving scans, see Saving Your Scans.
When you try to convert from a bitmap to a vector format, things get complicated. To convert a bitmap to vector, you need special software called tracing software. You can find tracing software, plus several other programs that offer batch mode conversion and advanced features listed in file format converters.
If you have vector illustration software, there's a good chance that you already have software for tracing bitmaps. CorelDRAW, Xara, Freehand, Flash, and many other drawing applications all come bundled with autotrace utilities. Don't expect to get instant results, however; this software works best on simple images and line drawings. In most cases, you'll spend less time and get better results by tracing the artwork manually in a vector drawing program.
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