ICT-1 Multimedia Lesson 2 (Part 1)
lossless compression
every single bit of data that was originally in the file remains after the file is uncompressed. The file does not lose information when saved and therefore the image retains the same quality of the original picture after each time it is saved, such as a GIF file.
Graphics software
software used to create and edit graphic images.
raster graphics file formats
Common types are JPG, PNG, TIFF, BMP, GIF, and PSD.
High-resolution
A resolution size of 300 DPI or higher. The graphic resolution typically used for printing. More image detail.
vector graphics file formats
AL, EPS, SVG
Raster
File formats made of grids of pixels, commonly referred as a bitmap. The larger the image, the more disk space the image file will take up. Best used for photos.
Transparency
It will allow you to have an image on that allows the background for other image to show through when placed on top of it.
Low-resolution
Typically any resolution less than 300 DPI. This is usually used for graphics where the final output is the computer screen. Examples of this resolution would be graphics for a Web site or graphics for a slide presentation. Less image detail.
AL
a proprietary vector file format developed by Adobe Systems for representing single-page vector-based drawings in either the EPS or PDF formats.
PNG (Portable Network Graphic)
a raster file format typically used for line art, logos, cartoons, and photos. The most used lossless image compression format on the Internet. This format supports transparency but does not support animation. A raster image format which is best used for webpages, but is not suitable for print.
PSD (Photoshop Document)
a raster file format which is a layered image file used in Adobe Photoshop. Adobe Photoshop is typically used by professionals and requires a subscription to Adobe Creative Cloud.
TIFF (Tagged Image File format)
a raster file format which is commonly used in desktop publishing, faxing, 3-D applications, and medical imaging applications. Image format produces a large file size that does not lose quality and is best used when saving photographs for print.
BMP (Bitmap Image File)
a raster file format which stores color data for each pixel in the image without any compression. This method of storing image information allows for crisp, high-quality graphics, and use image compression algorithms that can significantly decrease their file size.
JPG (Joint Photographic Experts Group)
a raster file format which uses "lossy" compression. This means the image quality is lost as the file size decreases. This format is typically used for photos. This format does not support transparency or animation.
EPS
a vector file format used in vector-based images in Adobe Illustrator as well as other software applications.
SVG (Scalable Vector Graphics)
an XML (Extensible Markup Language) based vector image file format for two-dimensional graphics with support for interactivity and animation.
Logo
an emblem, symbol, or graphic mark commonly used by organizations, associations, and commercial enterprises. Vector is the best image type.
vector
graphical images made up of mathematical equations; image file types not made up of a grid of pixels, but instead are comprised of paths, which are defined by a start and end point, along with other points, angles, and curves along the way. A path can be a line, a triangle, a square, or a curvy shape. When you increase the size of an original graphic, the edges of all the objects within the graphic will stay smooth.
Clip art
pre-made graphic images used to illustrate any medium. Raster is the best image type.
Resolution
the detail an image holds. The term applies to raster digital images, and other types of images. Typically measured in DPI or PPI. DPI is dots-per-inch. PPI is pixels-per-inch. DPI and PPI are typically used interchangeably.
Background graphics
the general scene or surface against which images, graphics, designs, or figures are represented or viewed.
Opacity
the transparency of an object.
GIF (Graphics Interchange Format)
this rater file format uses lossless compression that does not degrade the quality of the image. The GIF format supports both transparency and animation.
Web graphics
visual representations used on a Web site to enable or enhance the representation of a feeling or idea, in order to reach the Web site user. Web graphics include photographs, diagrams, designs and patterns, bar and pie charts, typography, line art, and many other image forms.
lossy compression
when a file is compressed or saved only a part of the original information remains. The file loses information when saved and therefore loses image quality each time it is saved (compresses) such as a JPG file.