TPJ 2005 No 03 , 2005 - 07 - 15 Rev . 2005 - 07 - 15 Strategies for including graphics in L A TEX documents Klaus

This article presents strategies for including graphics into LATEX documents. It shows the usage of the standard graphics packages of LATEX as well as an introduction to different graphics formats. Some external tools for converting graphics formats are discussed. 1 Overview of graphics formats In general, there exist two kinds of graphics formats: vector and bitmap graphics. For bitmaps, there exist different flavors: no compression (which can make your files truly huge, dependent on resolution and color depth, so I won’t cover them from here on), compression methods which completely preserve the image quality while reducing the data size, and “lossy” compression methods which cause a consequent reduction in image quality. So let’s go more into detail: Vector graphics are set up by drawing or filling geometrical objects such as lines, Bézier curves, polygons, circles and so on. The properties of these objects are stored mathematically. Vector graphics are in general device independent. It is easy to scale or rotate them without loss of quality, since the job of rasterizing them into actual pixels is done by the printer or printer driver. Bitmaps without lossy compression store the image information as pixels, each pixel of a given color. In principle, the quality of a bitmap becomes better with increased resolution and color depth (e. g. GIF files use a color depth of 8 bits, leading to 256 different indexed colors while a bitmapwith 24 bit color depth can have about 16 million colors). Scaling and rotating bitmap images will yield a loss of quality, and printing bitmaps to a device with a different resolution can produce bad results. Fig. 1 shows the difference between a scaled image as vector and bitmap graphics. Bitmaps with lossy compression use the fact that while the human eye is fairly good at seeing small differences in brightness over a relatively large area, it is not good at distinguishing brightness variations in a small area. Therefore, the detail information in the latter case can be reduced, leading to smaller file sizes. This works well for photographs that usually contain smooth transitions in color, but for graphics with a sharp border, artifacts can occur, as shown in fig. 2. The most prominent graphics format using lossy compression is JPEG. Figure 1: Zoomed view into a sample image as vector graphics (left) and bitmap (right).