Specific structure or arrangement of data code stored as a computer file.

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4 FILE FORMAT Specific structure or arrangement of data code stored as a computer file. A file format tells the computer how to display, print, process, and save the data. It is dictated by the application program which created the file, and the operating system under which it was created and stored. Reference:

5 RASTER JPEG GIF PNG TIFF PSD VECTOR EPS AI PDF

6 RASTER FILE Created by a fixed set of pixels in a grid pattern Simple illustrations to complex images like photographs Image sizes are dependent on number of pixels and color depth Once set, it will lose quality a lot easier, especially if trying to make it larger

7 RASTER FILE Created by a fixed set of pixels in a grid pattern Simple illustrations to complex images like photographs Image sizes are dependent on number of pixels and color depth Once set, it will lose quality a lot easier, especially if trying to make it larger VECTOR FILE Mathematical term, determined by magnitude and direction = line or path Defined start and end point more points added create curves, angles, and shapes Typefaces are created by paths and are mostly vector-based (i.e. font sizes) File size and quality does not change by scaling it; these are only affected by adding or subtracting to the file Easily scalable without loss of quality

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9 LOSSY vs. LOSSLESS Refers to image file compression = quality LOSSY: trade image quality for file size file looks like a perfect copy of the original but the representation is of far less quality LOSSLESS: does not compress as much (usually larger file size) will look like a perfect copy of the original, leaving the file most uncompressed

10 DPI = Dots Per Inch PPI = Pixels Per Inch Number of dots in a printed inch, ex. 300 dpi, 150 dpi Number of pixels per digital inch, describes pixel density of a screen or an image Resolution High or Low Measure of dots or pixels in an image or display, ex. 300 dpi, or width x height of a TV screen: 1920 x 1080 pixels Resolution also represents quality the higher the resolution, the more detail it needs to have

11 JPEG Joint Photographic Experts Group Lossy data compression, medium quality images Lower file sizes User friendly, share between wide variety of platforms Best use: web design, social media, digital photography GIF Graphics Interchange Format Low resolution, lower quality images Lower file sizes more colors added, larger the file size Handles transparencies well Animation (ex. memes and vines) Best use: web design, social media NOT good for digital photography

12 PNG Portable Network Graphics Lossless data compression, high quality images Can be higher file sizes (use sparingly on website, for less load time) Detailed photo images at higher quality than a JPEG Transparencies at higher quality than a GIF Best use: web design, social media TIFF Tagged Image File Format Lossless data compression, high quality images Higher file sizes too large to ever use on a website Supports layers, keeps original quality of files Best use: printing (professional and commercial), NOT web design, social media, or logos

13 PSD Adobe Photoshop Adobe Photoshop native format High quality, file size depends on complexity of the image Good for internal use Best use: printing EPS Encapsulated Postscript Uses vector and raster components Transfer PostScript-language between applications Raw elements, good for internal and external use Easily converted to PNG, JPEG, or GIF Best use: printing, screen printing, embroidery, promotional items, NOT for use on a website

14 AI Adobe Illustrator Adobe Illustrator native format Good for internal use Logos and illustrations Best use: printing, screen printing, embroidery, promotional items PDF Portable Document Format Open source, universal file format Hybrid of raster and vector images High & low resolution = image quality Can be used for both digital and print Best use: printing, clients, internal and external audience, downloadable files on website

15 Converting the File Formats Vector to Raster Easy Compresses vector into pixels Files no longer able to be manipulated or resized for same quality Always save original of vector files before rasterizing Raster to Vector No easy way Possibly trace the contents back into a vector

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