Digital Imaging

Introduction Digital Imaging is used every day in life. Has become less expensive and easier to use than film.

Charged Couple Device (CCD)

Filtering Accomplished with a beam splitter One pixel assigned for each color

Bayer Filter Pattern Alternates rows of green and blue, and green and red pixels Twice as many green as red and blue

Color Space Defines how colors are mixed together to form a specific color Two types: RGB and CYMK

Dynamic Range Good Dynamic Range Poor Dynamic range

Interpolation Nearest Neighbor interpolation Bilinear interpolation Bicubic interpolation Fractal interpolation

Resolution The level of detail captured by a digital camera Measured in Pixels Limited in display to the level of the monitor. Higher the resolution, the larger the image size that can be reproduced.

Noise Interference caused by electronics Usually the quality of the sensors and camera determines noise level Compression of files increases noise

White Balance Used to compensate for different lighting conditions Fluorescent will normally cause a greenish hue Halogen and mercury vapor will cause an orange-yellow hue Normally automatically adjusted in the camera

File Formats Tagged Image File Format (TIFF) Better compression format Doesn’t lose data in compression Requires adequate processor and memory Joint Photographic Experts Group (JPEG) Most commonly used format Used mainly for natural photos As compression increases, quality declines

Storage Variety of Types Files Normally stored in JPEG format Compact Flash, Smart Media, Memory Stick Images are transferred to the computer for storage

Digital Imaging Uses Home Uses Photography Photo editing Business Uses Publishing

Hubble Space Telescope

Medical Uses Changing from analogue to digital Allows Doctors to communicate information and get opinions of specialists thousands of miles away

Government and Law Enforcement Security Screenings Biometrics Prevent Fraud

Other Uses Archaeology Cosmetic Surgeons Beauticians

Conclusion How Digital Imaging Works Terminology File Formats and Storage Uses of Digital Imaging