To analyze the operation of imaging products, test equipment generates stable video signals with carefully defined characteristics that allow engineers to measure, analyze, and display the results of image digitization, processing, and display with signal and pattern generators, oscilloscopes, waveform monitors, or vectorscopes. This month, we look at manufacturers of signal generators and video test equipment.
Video instrumentation
www.colorado-video.com
Colorado Video (Boulder, CO) produces instruments for measuring dimensions, intensities, and positions within video images. The company's Web site provides descriptions of a number of crosshair, pattern, and character generators used to superimpose reference marks or alphanumeric data onto real-time video displays. In addition, there are descriptions of how the company's stand-alone video frame stores are integrated into systems for video microscopy, industrial quality control, image modification, and scan conversion.
Programmable test
www.quantumdata.com
Programmable video test generators are featured on the site of Quantum Data (Elgin, IL). Designed to emulate NTSC, PAL, and HDTV video sources, the units also can test PCs, graphics workstations, medical-imaging systems, and military display systems. Currently, this Web site features three series of video test generators. Whereas the Model 801 series includes five compact stand-alone models and four ISA expansion board models, the Model 822 series can generate monochrome analog video at pixel clock rates to 600 MHz. For incoming parts inspection, troubleshooting, and repair, the Model 600 series of hand-held video testers checks VESA, NTSC, PAL, and HDTV signals.
Analog to HDTV
www.team-systems.com
On the Web site of Team Systems (Santa Clara, CA), you'll find information describing analog PC-based, stand-alone, and digital video generators. Of particular interest are the Astro digital video generators for engineering, testing, interfacing, and evaluating flat-panel displays. They offer programmability to 8-bits/pixel at resolutions to 1280 x 1024 in single or multiplexed operation. Also described are HDTV test generators that are capable of delivering pixel frequencies from 5 to 400 MHz and horizontal scans to 300 kHz.
Test tutorial
www.tek.com
Perhaps the most informative video-test Web site is that of Tektronix Inc. (Beaverton, OR). In addition to providing information on video-measurement equipment, signal generators, and signal monitors, this site holds a wealth of tutorials, news, white papers, application notes, and primers. Check it out if you are looking for information on the basics of video, videoscopes, waveform monitors, and the latest MPEG-based broadcast test equipment.
PC add-ins
www.unigraf.fi
One of the product lines of Unigraf Oy (Espoo, Finland) is a range of PC-based test equipment. Rather than build stand-alone video generators, the company offers a number of PC add-in boards that allow the PC to be used to test electronic equipment. On this site, there are descriptions of the VTG-1135, -1250, and -1300 video test generators for manufacturing, evaluating, and servicing video monitors and the VTG-1108 signal generator for checking flat-panel displays.
Test and measurement
www.videotek.com
Manufacturer of test-and-measurement equipment, video demodulators, routing switchers, and color correctors and processors Videotek (Pottstown, PA) has a Web site that offers access to data on the company's NTSC, PAL, and digital products. Moreover, it offers a complete line of application notes covering such topics as video standards, digital compression methods, waveform monitors, and frame synchronizers. These can be viewed on-line or downloaded in Adobe Acrobat format.