Desktop Publishing Presentation Instructions

1. Desktop PublishingPresentation Instructions • Use the Navigation Buttons at the bottom of this window to move through the presentation. • Use the “Home” Button to go to the Menu if you want to jump to a specific section. END

2. Main Menu • What is Desktop Publishing? • Pixel • Resolution • Line Art • Grayscale • Halftone • RGB Color • Image Compression • Image Formats • Raster Images • Vector Graphics END

3. Slide 1 of 13 END

4. Desktop Publishing • “Desktop Publishing” applications are used to combine text, clip art, digitized images, etc. to produce brochures, flyers, newsletters, etc. Slide 2 of 13 END

5. Pixel • An image on the screen is made up of many small dots called “Pixels” (Picture Elements). • The pixel dimensions of the common “standard size” image from a digital camera are 640 pixels wide x 480 pixels tall. Slide 3 of 13 END

6. Resolution • “Resolution” refers to how small and close together the pixels or dots are. • The higher the resolution, the more dots there are per inch, and the “clearer” the picture. • A common screen resolution is 72 pixels per inch. • 300 dots per inch and greater resolutions are commonly used on scanners and printers for higher quality images. Slide 4 of 13 END

7. Line Art (monochrome images) • “Line Art” (monochrome) images consist of pixels that are either on or off, so they only require one bit of storage space per image pixel. Slide 5 of 13 END

8. Grayscale • “Grayscale” images consist of pixels which can be various shades of gray. • 8-bit Grayscale images can have 256 different shades of gray and require one byte of storage space per image pixel. Slide 6 of 13 END

9. Halftone • “Halftone” gives the effect of shading by using various patterns of dot groupings, as is commonly seen in newspaper images. Slide 7 of 13 END

10. RGB Color • “RGB” stands for “Red-Green-Blue”, the three primary colors of light. By combining various intensities of each of these colors, any color can be created. Slide 8 of 13 END

11. 24-bit per pixel RGB color uses one byte (8-bits) to describe the intensity of each primary color, giving over 16 million possible colors requiring three bytes of storage space per pixel. Slide 9 of 13 END

12. Image Compression • If not “compressed”, a 640 by 480, 24-bit RGB color image will require:640 x 480 x 3 = 921,600 bytes of memory. • Images are commonly “compressed” so that they will require less storage space and so they will download quicker. • Compression usually results in a reduction in image quality. Slide 10 of 13 END

13. Some Common Image Formats • JPEG - Compressed image format for photographic type images with many colors (common on web). • GIF - Used for Clip Art and Icons or images with limited colors (common on web). • PNG - (Portable Network Graphic) Can be used for images on the web requiring transparency. • TIFF - A high-quality photographic image format. • BMP - A photographic format common on the PC. • PICT - A photographic format common on the Mac. Slide 11 of 13 END

14. “Raster” vs. “Vector” Graphics • "Raster" images are "Pixel-Based", with the color of each pixel individually defined. • Using "Paint tools" you can select, manipulate, and edit individual pixels in a Raster Image. • Raster graphics cannot be scaled to a higher resolution without a loss of quality. • Raster graphics are more appropriate for free-form or artistic images such as photographs. Slide 12 of 13 END

15. Vector Graphics • "Vector" graphics are "Object-Oriented", utilizing geometric objects such as curves and polygons to represent an image. • Using "Draw tools" you can select, manipulate, and edit geometric objects in a Vector Graphic. • Vector graphics can be easily scaled to a higher resolution without loss of quality. • Vector graphics are more appropriate for graphic design and technical illustration where precision and scalability is important, such as Computer-Aided Drafting (CAD). Slide 13 of 13 END