RASTER GRAPHICS 2.01 Understand Digital Raster Graphics RASTER GRAPHICS Also called bitmap graphics Consist of grids of tiny dots called pixels Have a fixed resolution and cannot be resized without altering or losing image quality Edited in paint programs RASTER GRAPHICS Can support high color depths. Most common type of raster is a digital photograph. Great for adding special effects such as filters & blurs. Work well for web design. Used to create images for print design such as magazines. 3 RASTER GRAPHICS Native File Formats: file formats that are default file format that are proprietary to a specific program that are generally not meant to be used with other software. Standard File Formats: file formats that can be used with a variety of software programs. Standard file formats are usually created by using the “Save As” command or through exporting. Standard file formats include, but are not limited to: .gif, .jpg, .png, and .tif. 4 COMMON RASTER FORMATS PSD PNG JPEG TIFF GIF PDF 1.01 Investigate graphic types and file formats. PSD – PHOTOSHOP DOCUMENT Native file format for Adobe Photoshop Supports transparency Supports layers, text, and effects Large file sizes. Industry standard for raster graphic editing 6 GIF – GRAPHICS INTERCHANGE FORMAT Most common format for: Standard format for animation on the Internet Text Supports transparency Lossless compression Colors = 256 (8-bit) Clip art, animations, icons, logos Simple diagrams, line drawings Graphics with large blocks of a single color Graphics with transparent areas Images displayed on computer screens and on websites. JPEG – JOINT PHOTOGRAPHIC EXPERTS GROUP X X Does not support animation or transparency Lossy compression. Colors – 16.7 M (24-bit) High quality Commonly Used For: Desktop publishing photographs Photographs and natural artwork Scanned photographs Emailing photographs Digital camera photographs PNG – PORTABLE NETWORK GRAPHICS X Does not support animation Commonly Used For: Supports transparency Lossless compression Supports multiple color depths PNG 8 – 8 bit color Small Graphics PNG 24 – 24 bit color Basic Graphics Replacing GIF and TIFF images Online viewing of images See examples at http://graphicssoft.about .com/od/freedownloads/ l/blfreepng07.htm TIFF – TAGGED IMAGE FILE FORMAT X Does not support animation or transparency Available in compressed (lossless) and uncompressed formats Compressed is advised Colors – 16 M (24-bit) Commonly Used For: Storage container for faxes and other digital images To store raw bitmap data by some programs and devices such as scanners High resolution printing Desktop Publishing images 1.01 Investigate graphic types and file formats. PDF – PORTABLE DOCUMENT FORMAT Open source, platform independent format that embeds fonts, images, layouts, and graphics Allows choice of lossy and lossless compression Supports 16 million colors Viewable with Acrobat Reader, a free program by Adobe Commonly used for: Sharing files regardless of available software Share files that can be protected from copying or editing Publishing electronic documents and ebooks 11