IMAGES

1. IMAGES

2. IMAGE FORMATS GIF (Graphics Interchange Format): • Commonly used to display graphics & images in HTML documents over the web & other online services and applications • Limited to 8 bit(256) color images • Efficiently compresses solid areas of color while preserving sharp details such as line art, logos • Supported by most of the browsers • Comes in two formats, the original is GIF87a & other is GIF89a that supports animation

3. JPEG • Used to display graphics & images in HTML documents over the web & other online services and applications • Supports CMYK, RGB, Gray scale color models • Uses 24 bit format ,so retains all color information in an RGB image • Uses powerful but lossy compression methods that produce file as much as ten times more compressed than GIF • JPEG compression is slow

4. PNG (Portable Network Graphics) • Used for lossless compression • Supports 48 bit of color information and produces background transparency without sharp edges • Some browsers don’t support PNG image • PNG preserve transparency in grayscale and RGB • Supports RGB, grayscale, bitmap mode

5. TIFF (Tagged Image File Format) • Was designed to be a universal bitmapped image format • Used to exchange files between applications and computer platform • Supports pixel resolution of 48 bits • Supports different color models, RGB, CMYK, Grayscale images

6. Computer Color Model • Color Model is an abstract mathematical model describing the way colors can be represented • Colors are represented using a combination of red , green and blue. • Red + green=orange • Various Color Models are RGB, CMYK,HSB,CIE,YUV

7. RGB Color Model • It is additive method because color is created by adding the light sources in three primary colors • Name of the model comes from the initials of the primary colors • This model is used for TV and Computer Monitors • RGB is a device dependent color space

8. CMYK Color Model • Subtractive Method • Color is created by combining color media such as paints or ink that subtracts some parts of the color spectrum of the light and reflect the other back to eye • Used to create color in printing • The printed page is made up of tiny halftone dots of three primary colors C-cyan, M-Magenta, Y-yellow, B-Black

9. HSB Color Model • HSB Stands for Hue, Saturation, Brightness • According to this model, any color is represented by three numbers • First Number is Hue, its value ranges from 0 to 360 degrees, each degree represents a different color • First there is Red Color(0 or 360 degree), then there are all other colors eg yellow at 120,Green at 180, blue at 240 degrees upto violet.

10. Comparison of various Color Models