- What are some advantages of digital videos Switched digital video systems' most obvious advantage is that they address one of the biggest problems cable companies have -- running out of bandwidth. As more people sign up for HDTV services, high speed cable modems and VOD, cable companies have to find a way to deliver. An SDV system helps cable companies implement a solution without replacing miles of cable, since the system can work on top of an existing infrastructure.Increased bandwidth can also lead to more services. A cable company could choose to increase the number of channels it offers, allowing it to compete more effectively with satellite television companies. Additional channels could include more HD feeds or programming catered to a particular region.Cable companies provide Internet access in much the same way they provide television feeds. Companies feed Internet downstream through 6-megahertz (MHz) channels in the cable bandwidth. Upstream feeds, the information sent back through your modem to the Internet, goes into a 2 MHz channel. When customer demand gets heavy, the cable company creates a new 6 MHz channel to relieve stress on the system. With SDV, cable companies have more bandwidth available to convert into Internet channels during periods of high customer demand.
- What is meant by frame rate in video
frame rate you get on your computer. For example, your PC processor or graphics hardware may only be capable of playing 10-15 frames per second without acceleration.
he industry. The professional frame rate for motion pictures is 24 frames
- Are all videos/movies the same frame rate, explain your answer No , not all videos and movies are not in the same frame rate as various cameras, and Television have different camera rates.
- What is meant by resolution, how is it measured?
- Image resolution describes the detail an image holds. The term applies to raster digital images, film images, and other types of images. Higher resolution means more image detail.The resolution of a monitor is measured in picture elements, or "pixels" for short. Pixels are tiny dots that display on a computer monitor in one of millions of colors, shades and hues. To the viewer, the many pixels in a computer monitor combine to form a viewable picture.A pixel is the smallest element of a video image, but not the smallest element of a monitor's screen. Since each pixel must be made up of three separate colors, there are smaller red, green, and blue dots on the screen that make up the image. The term dot is used to refer to these small elements that make up the displayed image on the screen. In order to use different resolutions on a monitor, the monitor must be able to support automatic changing of resolution modes. Originally, monitors were fixed at a particular resolution, but most monitors today are capable of changing their displayed resolution under software control. This allows for higher or lower resolution depending on the needs of the application. A higher resolution display shows more on the screen at one time, and the maximum resolution that a monitor can display is limited by the size of the monitor and the characteristics of the CRT (cathode-ray tube). In addition, the monitor must have sufficient input bandwidth to allow for refresh of the screen, which becomes more difficult at higher resolutions because there is so much more information being sent to the monitor.
14" 15" 17" 19" 21" 640x480 BEST GOOD TOO BIG HUGE TERRIBLE 800x600 GOOD BEST GOOD TOO BIG HUGE 1024x768 TOO SMALL GOOD BEST GOOD STILL GOOD 1280x1024 TINY TOO SMALL GOOD BEST GOOD 1600x1200 TERRIBLE TINY TOO SMALL GOOD BEST
- What is the colour system called RGB
The RGB color model is an additive color model in which red, green, and blue light is added together in various ways to reproduce a broad array of colors. The name of the model comes from the initials of the three additive primary colors, red, green, and blue.
The main purpose of the RGB color model is for the sensing, representation, and display of images in electronic systems, such as televisions and computers, though it has also been used in conventional photography. Before the electronic age, the RGB color model already had a solid theory behind it, based in human perception of colors.
- Explain the video standards PAL, NTSC, and SECAM, what are the main differences between them.
| The system used in America & Canada is called "NTSC". Western Europe and Australia use a system called "PAL", and Eastern Europe and France use "SECAM". Without standards conversion, it is impossible to view a video program that is recorded in a foreign country without first converting it.. Here are some charts illustrating the differences |
N T S CNational Television System Committee | |
| Lines/Field | 525/60 |
| Horizontal Frequency | 15.734 kHz |
| Vertical Frequency | 60 Hz |
| Color Subcarrier Frequency | 3.579545 MHz |
| Video Bandwidth | 4.2 MHz |
| Sound Carrier | 4.5 MHz |
P A LPhase Alternating Line | |||
| SYSTEM | PAL | PAL N | PAL M |
| Line/Field | 625/50 | 625/50 | 525/60 |
| Horizontal Freq. | 15.625 kHz | 15.625 kHz | 15.750 kHz |
| Vertical Freq. | 50 Hz | 50 Hz | 60 Hz |
| Color Sub Carrier | 4.433618 MHz | 3.582056 MHz | 3.575611 MHz |
| Video Bandwidth | 5.0 MHz | 4.2 MHz | 4.2 MHz |
| Sound Carrier | 5.5 MHz | 4.5 MHz | 4.5 MHz |
SECAMSequential Couleur Avec Memoire or Sequential Color with Memory | ||
| SYSTEM | SECAM B,G,H | SECAM D,K,K1,L |
| Line/Field | 625/50 | 625/50 |
| Horizontal Frequency | 15.625 kHz | 15.625 kHz |
| Vertical Frequency | 50 Hz | 50 Hz |
| Video Bandwidth | 5.0 MHz | 6.0 MHz |
| Sound Carrier | 5.5 MHz | 6.5 MHz |
- Which standard do we use in
Australia
We use 'PAL' otherwise known as 'Phase Alternating Line'
- What is an IEEE 1394 port
The IEEE 1394 interface is a serial bus interface standard for high-speed communications as well as in digital audio, digital video, automotive, and aeronautics applications. The interface is also known by the brand names ofFireWire (Apple), i.LINK (Sony), and Lynx (Texas Instruments). IEEE 1394 replaced parallel SCSI in many applications, because of lower implementationcosts and a simplified, more adaptable cabling system.
- Why do digital video cameras use video compression
Digital cameras use video compression as to allow a higher resolution on the computer.Many types of video compression exist for serving digital video over the internet and on optical disks. The file sizes of digital video used for professional editing are generally not practical for these purposes, and the video requires further compression with codecs such as the Windows Media format, MPEG2, MPEG4, Real Media, and more recently H.264. Probably the most widely used formats for delivering video over the internet are MPEG4 and Windows Media, while MPEG2 is used almost exclusively for DVDs, providing an exceptional image in minimal size but resulting in a high level of CPU consumption to decompress.
- Describe what a codec is. A codec is a device or computer program capable of encoding and/or decoding a digital data stream or signal. The word codec is a a format is a document (the standard), a way of storing data, while a codec is a program which can read or write such files. In practice "codec" is sometimes used loosely to refer to formats, however.
- What is meant by “generation loss”, where does it happen? Generation loss refers to the loss of quality and potential increase of file size between subsequent copies of data. Anything that reduces the quality of the representation when copying, and would cause further reduction in quality on making a copy of the copy, can be considered a form of generation loss
Generation loss occurs with increased distortion, increased noise, change in frequency response, and change in the relative phase of one frequency component with respect to another.
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