1. 2.01 Understand Digital Raster Graphics

2. Raster Graphics Also called bitmap graphics
Consist of grids of tiny dots called pixels
Have a fixed resolution and cannot be resized without altering image quality
Edited in paint programs
Teacher Note: Enlarging raster graphics causes them to become pixilated (you can see the individual blocks of colors that make up the image).

3. Raster graphics Can support high color depths.
Most common type of raster is a digital photograph.
Great for adding special effects.
Work well for web design.
Used to create images for print design.

4. 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.

5. Common Raster Formats
PSD
JPEG
GIF
PNG
TIFF
PDF

6. PSD – Photoshop document
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

7. GIF – Graphics Interchange Format
Most common format for:
Text
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.
Standard format for animation on the Internet
Supports transparency
Lossless compression
Colors = 256 (8-bit)

8. JPEG – Joint Photographic Experts Group
Commonly Used For:
Desktop publishing photographs
Photographs and natural artwork
Scanned photographs
ing photographs
Digital camera photographs
Does not support animation or transparency
Lossy compression.
Colors – 16.7 M (24-bit)
High quality
Teacher Note: This format is best for images containing many colors or shades of color. Most digital cameras save the images made with the camera as JPEG files on their memory cards.

9. PNG – Portable Network Graphics
Does not support animation
Supports transparency
Lossless compression
Supports multiple color depths
PNG 8 – 8 bit color
Small Graphics
PNG 24 – 24 bit color
Basic Graphics
Commonly Used For:
Replacing GIF and TIFF images
Online viewing of images
See examples at
Teacher Note: Browser software or image editing program may require the user to download a plug-in before recognizing or opening the file.

10. TIFF – Tagged Image File Format
Does not support animation or transparency
Available in compressed (lossless) and un-compressed 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
Teacher Note: TIFF images have very high quality which is ideal for faxes or printed images, such as those used in desktop publishing. However, this results in a large file size so it is not recommended for images that will be viewed over the Internet.
Large file sizes; not recommended for web viewing

11. PDF – Portable Document Format
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