05-06-2012, 05:39 PM
CAMERA COMPUTER INTERFACES
CAMERA COMPUTER.ppt (Size: 2.24 MB / Downloads: 0)
INTRODUCTION
To get an image data from physical sensor into the processing unit.
Processing unit- process the image and initiate an action .
TYPES OF INTERFACES
PC Based Machine Vision Systems
Smart cameras
Embedded compact vision systems
Most preferred -PC based systems
WHY PC BASED SYSTEMS?
Performance average
Flexible
Economical
Good performance for the price
TYPES OF DATA TRANSMISSION
Analog Transmission- Single wire carries analog signal that encodes image and data timing info.
Digital Transmission- also called brute force transmission .
Consist of RS 422, LVDS and buses like USB, IEEE1394(Fire wire (Apple).
OTHER VIDEO STANDARDS
Monochrome Video Standards
Types- EIA,CCIR
EIA-Electronics Industries Association-RS 170-North America
CCIR- Consultative Committee for International Radio- Europe.
S-VIDEO
Video requirement- High Resolution, Accuracy, Integrity.
Transmission through single wire- Bleed of chroma→ Distortion→ Noise
Transmission through Two separate wires- same timing and synch as composite video
Applications- Machine Vision Applications, Consumer Devices
Adv- more image clarity.
Disadv-cost more due to extra cabling
DIGITAL TRANSMISSION
The process here is similar except that phase modulation, amplitude modulation, frequency modulation is substituted with Frequency And Phase shift keying.
The decoding unit will carry analog to digital converters (if reqd).
