Video test pattern generators provide a convenient and effective way to calibrate, test and troubleshoot video display devices such as HDTVs, projectors, LCD (liquid crystal display) screens and CRT (cathode ray tube) monitors for the ideal viewing experience.
Specific patterns are produced by the video test pattern generators to determine a variety of performance criteria, including: video resolutions, brightness and uniformity, purity and color saturation, linearity, edge geometry, sharpness, stability, etc. By comparing the video input pattern to the video output on a display unit, it is possible to determine how accurately a monitor displays the video it receives and if any defects can be rectified. Some video test pattern generators also allow a user to test digital and/or analog audio signals through generated frequency waves. Using the corresponding video cable needed, simply connect the video test pattern generator to the supported display unit to run the test patterns on the screen. No other video source, such as a computer, DVD player or set-top box is needed for the testing process. If multiple display units are to be compared, the use of a video splitter can ensure that the same pattern is displayed on all desired monitors and subsequently calibrated so that the video output is identical on all screens.
Three of the most common video test patterns are: color bars, grayscale charts and crosshatch, with each serving a distinct function. Several variations of the color bar test pattern exist, with the most well-known being the SMPTE color bar, which are used to test analog NTSC video. All color bar test patterns serve the same purpose of testing and calibrating color saturation, balance and brightness. Most grayscale charts consist of a gradient of monotone bars with the goal being to obtain a smooth range of neutral grays from pure black to white. Adjustments can be made to brightness and contrast to achieve the optimal display. Crosshatch patterns are used to check and calibrate centering, aspect ratio, convergence, and both vertical and horizontal linearity. Other test patterns can range from focusing on one or two specific issues to universal patterns that cover most key aspects.
Most video test pattern generators are compact, portable devices that allow easy field calibration, testing and maintenance of many applications such as: production line quality assessment; studio equipment for both installers and users; television sets by TV engineers or technicians; digital signage configurations with extenders, switches, splitters or video wall processors; and discerning home theater users. High-end models tend to support multiple video signal types while lower-end models offer a more limited and specific selection. Video Products Inc (VPI) offers a wide selection of video test pattern generators that can fulfill the needs of varying applications.
VPI’s MONTEST-HDMI and MONTEST-HDMI-LC respectively provide a high-quality and low-cost option for testing HDMI or DVI display units. The low-cost unit can generate 34 video test patterns, 48 timings and a single audio tone. In comparison, the MONTEST-HDMI provides 39 distinct test patterns, 35 resolution and timing settings, and a range of analog and digital audio signals via a built-in sine wave tone generator. It can also be controlled via the IR remote control or RS232 in addition to its front panel buttons. Both units can test for HDCP compliance and support HDTV resolutions up to 1080p.
The MONTEST-LCD signal generator supports analog computer monitors, LCD displays and video projection systems with the following four connectors: VGA, MAC II, SUN and RGHHV for BNC. It can generate four video patterns with 16 colors and intensity control, and over 100 frequencies that cover a wide range of monitor types.
The MONTEST-HDSDI can generate eight video test patterns and seven timings up to 1080p resolution at full broadcast quality, making it ideal for testing and maintaining studio equipment such as monitors, cabling and recording equipment. It also supports single-tone audio testing and dual SDI output for side-by-side comparison of displays.
All encompassing, the MONTEST-DA supports both analog and digital video signals, including: HDMI, DVI, NTSC, PAL, component Y/Pb/Pr, S-video, VESA, and more. It not only provides a variety of video test patterns, but also allows a user to play stored video and audio files from an embedded 80G hard drive. Remotely control the unit via its RS232-port. Supporting stereo audio test signals, DDC2B, and HDCP, the unit can scale a source to fit a display based on its EDID data. The MONTEST-DA is an ideal, comprehensive solution for applications that need to test, calibrate and maintain various display types.
Video test pattern generators are necessary for achieving optimal displays in many different settings and VPI’s range of MONTEST video test pattern generators can help both consumers and businesses achieve the highest quality their display units can deliver.
Ever since the 1960’s, satellite TV has become more and more impactful to our TV viewing experience and satellite TV technology has continued to improve. New technology keeps pushing the boundaries and changing the way satellite TV is viewed. What started out as a fuzzy black and white picture has now become HDTV with amazing quality.
Here are some ways satellite TV service has improved:
1. Improved Accessibility – Many people in rural areas couldn’t get cable TV because of the expense and limitations of running the cable. With improved technology, anyone with a clear view of the Southern sky can get satellite reception.
2. Increased Program Offerings – With the improvements in technology, it has become possible to transmit more TV channels from one satellite. Many consumers, with improved receivers, can get even more TV channels than ever before. This means more entertainment, more news and information and more value for your money.
3. Digital Technology – Satellite TV service took a giant step forward with digital transmissions in terms of quality and capacity. Digital transmissions take less bandwidth than analog, so the switch created a lot more room for HDTV broadcasting and more channels. Plus, audio and video quality improved as well. With MPEG compression, theater quality video and Dolby quality stereo audio can be delivered into millions of homes with ease.
4. High Definition Television Receivers – Today, most of the TV’s sold are now HDTV’s. HDTV, with an HD satellite receiver, not only offers improved image quality over SD but also presents with a 16:9 aspect ratio instead of 4:3 which makes for a wider screen. What this means is, none of the quality is lost when the picture is modified to fit your screen.
5. Internet Integration – Joining the technology of both the internet and satellite TV by having increased bandwidth makes for a better viewing experience. Being able to watch what you want when you want has now become very possible through the combination of these two technologies.
As technology continues to progress, we’ll see even more amazing increases in quality and capability. Three-D is becoming more and more popular, more channels are coming online and the internet continues to push the envelope when it comes to information integration. And the best part of all of the improvements in technology, aside from quality, is the fact that it’s affordable for virtually everyone. It’s so easy to enjoy your viewing experience knowing that satellite TV is an inexpensive way to get your entertainment.
Keeping up with the latest satellite TV technology is a great way to know what is best for you. Johney Maron got an HD satellite receiver for his HDTV and a DVR that lets him record whatever he wants.
DTV Means Digital Television
Many users watch TV on an analog TV set with a 4 x 3 screen. As digital television enters more and more into the mainstream with wide-screen capability and higher sound and visual standards. Digital Television transforms television technology which allows broadcasters to offer television programming with movie quality picture and Cd quality sound. DTV technology transmits large amounts of data which can also be accessed by computer or on the television set.
DTV is the first enhancement of television since the National Television Standards Committee (NTSC) wrote guidelines for television transmission in the United States in 1941. RCA developed a color standard which NTSC adopted for its commercial broadcasting in 1953. The system of 1953 was improved over the years by newer and higher quality technology but the system didnt change. Digital Television is the current upgrade of television technology.
A pixel is a PICture ELement and it actually is the smallest resolvable square of an image. Each picture consists of 3 even smaller dots of the colors red, green and blue. Together these 3 dots can create all the colors the viewer sees TV. A pixel is small enough for a viewers eyes to think that they are 1 dot on the screen and even though each pixel in fact shows 3 different colors the eyes perceive them as 1 color. DTV improves the resolution of TV by putting more than 4 pixels in the same space that analog TV uses for 1 pixel. Also in Digital TV each pixel is exactly square. Analog TV uses a slightly higher than wide pixel which is why sometimes analog TV shows distortions of the image.
The resolution of an analog television screen is very low. The NTSC standard sets for 486 active lines where DTV is set for 1080 active lines. The number of pixels on each line is only 720 where Digital Television can go as far as 1920 pixels per line. This is a vast improvement upon standard analog television.
Widescreen As a result of TV the movie theaters had to come up with a solution to compete with TV at home. The viewing experience in the movie theater had to be better otherwise nobody would care anymore to go to a movie theater. They tried many things but the best working solution was a wider screen.
Because the way we see is a more rectangular wider view, a wider viewing area gives much more visual information than the squarer image of analog TV (ratio of 4 wide by 3 high). DTV and a more specific version of it, HDTV, uses a ratio of 16 wide by 9 high. This wider screen improves the viewing experience to match the format used in the movie theaters.
Sound Analog TV can handle 2 audio channels whereas DTV can handle 5 audio channels and thus gives the possibility to have a home theater with surround sound to create a movie experience in the home.#
Better picture and better sound are the obvious advantages of DTV, but why is the fact that it is digital also an advantage? Its true that the same result can be achieved with an analog system. For that the viewer doesnt need to go digital. Japanese HDTV for example is transmitted over an analog signal. But there are some other advantages to digital systems.
Digital Television provides more data than analog. The information transmitted doesnt deteriorate over distance. Analog signals lose quality over distance while a digital signal doesn’t lose any quality.
With a higher quality image and sound DTV uses much more data than analog TV. Broadcasters in the United States are not allowed to use more bandwidth for 1 channel, so they somehow have to squeeze the additional data into the same channel.
MPEG-2 is the compression software used to put this additional data onto the channel. Because the information is digital, the data can be compressed into much less bits. The receiver has to decompress and the original data is back. MPEG-2 can reduce the amount of bits by a factor of up to 55.
Consider that standard analog TV has a resolution of 378,000 pixels where Digital Television can go as high as 2,073,600 pixels. A compression factor of 55 is more than 10 times than required so MPEG-2 is more than enough to squeeze much more data into the available bandwidth of a standard analog TV channel. All DIRECT TV Programming comes with digital quality picture and sound.
LED’s also referred to as lighting emitting diodes, are electric factors that exhibit an apparent coloring dependent on some level of latest place inside the diode. higher present produces darker colors, jointly with vice versa, in accordance thinking about the lighting spectrum. LED’s have been implemented in electronics for decades, as well as the newest innovations in LED solutions exclusive brought us this sort of significant type objects as HDTV and several LED-based toys and supplies.
High Definition tv may be considered a latest growth in tv set up broadcast and viewing in which an electrical signal is broadcast providing a bigger resolution inside the image inside the display than what a regular tv can. The image often clearer and much more extremely correct in definition that conventional tv by getting displayed on one of a few of significant types of monitors. one is plasma tv for pc technology. another is certainly fluid crystal display (liquid extremely display) know-how.
Encouraged solutions arrives in the direction of engage in much more prominently in tv as backlighting for all screens. The real fluid crystal screen, the identical solutions for just about any electric watch, is darkish by method of its nature, and youngster should be see a scene concerning the tv screen, LED solutions is carried out to brighten the display from at the rear of so concerning create the image noticeable concerning the viewer.
LED’s are large by nature, and the development on the full-screen LED TV is currently under design construction business, particularly in the pants pocket size TV market. Many TVs overseas that get into the pocket TV category are sold in LCD format, and, once again, are backlit by LED technology. The introduction of TV sets that use LED’s to form the main picture is literally being developed overseas, and in an experimental manner with the U.S.
The backlighting ability linked to LED technology was first implemented with the early 1990’s in Personal Digital Assistants and hand-held gaming system and cell phone screens. The particular technology has propagate around many electronic products from MP3 players and therefore portable DVD players.