Introduction of Illustrator

About vector and rastor graphics

On a computer monitor, images are nothing more than variously colored pixels. Certain kinds of image-file formats record images literally in terms of the pixels to display. These are raster images, and you can edit them only by altering the pixels directly with a bitmap editor.

A bitmap is basically an array of pixels with values indicating the color. The bitmap sizes are defined in pixels. BMP, TIF, GIF, JPG, PNG and most other graphics formats are raster graphics. Since the sizes are measured in pixels, the print dimension depends on the resolution of the printer. BMP records every pixels in the image, so the size is very big even for small images. Other formats use compression algorithm to reduce the file size without causing great visual degrading, but remember the barcode is read by machines other than human. Overall, you need to keep the physical size unchanged otherwise you will run into problems.

A vector graphic contains the drawing instructions other than the color value in pixels. In Windows platform WMF is most widely used vector graphic format that is supported by all printers. The best feature about WMF is that the dimension measures are completely device independent. It can be easily scaled without losing any characteristics( most likely you will not use the scale feature). We strongly recommend that you save your barcode image in this format. In our Barcode Studio/ActiveX products copy/paste operation is based on WMF format which preserves all the information. Other vector graphics formats include EPS (Encapsulated PostScript), SVG (Scalable Vector Graphics) format. To use EPS, you need to have a printer with postscript enabled. SVG is designed to use with World Wide Web, but they are not widely accepted. WMF is only supported in Windows platforms.

What is the difference between vector and raster graphics?

The difference between vector and raster graphics is that raster graphics are composed of pixels, while vector graphics are composed of paths. A raster graphic, such as a gif or jpeg, is an array of pixels of various colors, which together form an image. A vector graphic, such as an eps file or Adobe Illustrator® file, is composed of paths, or lines, that are either straight or curved. The data file for a vector image contains the points where the paths start and end, how much the paths curve, and the colors that either border or fill the paths. Because vector graphics are not made of pixels, the images can be scaled to be very large without losing quality. Raster graphics, on the other hand, become "blocky," since each pixel increases in size as the image is made larger. This is why logos and other designs are typically created in vector format -- the quality will look the same on a business card as it will on a billboard.

You can enlarge the vector graphic without any loss of quality ... but raster graphic will be dotted and loss all of it's quality when zoom in or when trying to enlarge.

Raster graphic represents by dots per pixel ie the picture contains say a 1000 dot .. every dot have a certain color .

The vector graphic represented by an mathematical equation, so if you try enlarge the vector picture the mathematical equation will take the hard and redraw the picture any size without any loss.

In illustrator programm draw a car and put your personal picture beside it ... now zoom ....zoom more ...?? what do u find ???? the car didn't pixelized and it have a perfect quality, but your picture was damaged.