IMAGE FILE FORMATS Lecture

* Image Size/ Memory (kb, mb, gigs)

1. Bytes (increases with the number of Pixels

• 8bit file (256 colors)
• 24 bit file (16 mil colors) “true color”

* Image Compression

1. Lossless-compressed images without loss of original data. "Lossless data compression is a class of data compression algorithms that allows the exact original data to be reconstructed from the compressed data.
2. Lossy-compressed with loss of original data (smaller) "A lossy compression method is one where compressing data and then decompressing it retrieves data that may well be different from the original"

Raster/bitmap, pixmap File Formats

• JPEG (lossy)-8bit
• PNG-8bit (lossless) improvement on the jpeg.
• TIFF-(lossless) Printing Industry (not for web)
• GIF(lossless)-8bit-used for animation and simple graphics on the web/
• PNG-24 bit “true color” open source, good for editing pictures
• RAW (lossless) smaller than tiff’s, used by photographers, not recognized by all editing software

Vector Format

SVG-all purpose vector graphic compatable with web applications

Adobe File Formats

.psd Photoshop
.ai Illustrator
.id Indesign
.pfd Portable File Document


Sources

Download: Server, Web
Upload: Scan- Print/Film-negatives and slides
Import: Camera/Camcorder
Create: Graphics Software- Adobe-PS, AI