Digital camera, Types of digital camera, optical readers

Digital Camera

Digital camera is an input device that takes picture and store them as digital images. Digital camera store captured image storage in our camera or on some type of memory card. Photo taken with a digital camera are typically transferred to a computer using a wired or wireless connection. Many digital cameras allowed the user to edit the image that the number of digital photos depend on the amount of memory in the camera. The main advantage of digital camera is that making photo is enough and save and fast. It does not require any film processing management phone and other mobile devices has built-in digital cameras digital still cameras are available in a wide variety of sizes and capabilities.

A quality of digital camera photos depend on its resolution  and describes the  sharpness of an image. Image resolution for Digital Camera is measured in Megapixel. Megapixel are million of pixel in a graphic, today's cameras are typically between 5 and 20 Megapixel.

Types of Digital Cameras

1. Point-and- Shoot Camera

A point and shoot camera is an affordable and light weight digital camera.It has lenses built into it and a screen that displays an approximation of the image to be photography point and shoot camera are available in wide variety of sizes and capability with it provides  acceptable quality photographic images for the home or small business user. Most point and shoot camera includes room and autofocus capability and use built-in flash many. Point and shoot camera can also take videos.

DSLR Camera

It stand for Digital  signal lens reflex  camera. It  is the most versatile and expensive type of digital camera. It allows the user to change the lenses to get the required room. Its lense's  cost $100,000. It has a screen to display the image to be photography. The user can manually adjust focus and exposure. Many DSLR are can also record high definition videos. The DSLR camera are much heavier and larger than point and shoot cameras.

Video Input

The process of entering full motions recording into a computer is called video input or video capture. Video can be and read from an analogue device like PCR but the analogue signal must be converted into digital format before storing it in the computer and expansion card that convert the analogue video signal into digital signal is called video capture cord.

The video camera that records video as digital signal instead of analogue signal is called digital video camera. Mini digital video camera capture still Fareb as well as motion with their cameras are connected to the computer through USB port  wire port on the system unit.

Webcams

Webcam is also called PC video camera. It is a type of digital video camera that can be used for the following purpose

. Capture video and still images

. Send emails with video attachments

. Add live images over the Internet

. Make video telephone calls on the Internet etc.

Web cam are normally placed on the top of the monitor. Most note book computers have built-in webcam, webcams can be attached to the computer through USB port are firewire port. Some cameras are portable and can be detached easily.

Some webcam display output on the web page this use of web cam attract websites visitor as different images and displayed on the website regularly. It is normally used to show any work in progress some websites use live webcam to display still picture at the specified time or time in travel such as 20 second.

Video Compression

The process of minimising the size of video clip is called video compression. Video compression recognise that only a small part of a video change from frame to frame. Video compression software story with the first frame completely if then stories only the changes for a One Frame to the another computer. It also use video recorded. Video  recorder is a card that record the video data. It is more effective than compression software video digitiser capture individual frame from an analogue video and save the picture in a file.

Video Conferencing

Video conference is a meeting between two or more people over the internet. The people sitting at distant location can transmit audio and video data. Video conference required microphone, speaker and a video camera attached to the computer. When one partispends speaks the other partispends hear his voice.

Video conference also provides  whiteboard. It is a window on the second to display notes and drawing on the screen of all participants. Video conferencing is a cost-effective way to contact business meeting, training and educational classes etc.

Scanner and Reading Devices

You read data information from a source. The source could be a written document, a price tag a graphic image or a photograph of scanning device. It ead the data information and then convert it into a form that can be processed by the computer.Two type of scanning device are optical scanner and optical readers.

1.  Optical Scanner

An optical scanner is also known as light sensing device. It is a light sensing input device that reads printed text or graphics and translate it in digital form. The scanned image can be used for different purposes as follows:

. It can be displayed on screen.

. It can be printed on the paper.

. It can be posted on a web page.

2.  Optical  Reader

Optical reader is a device that uses a light source to read character, marks and codes then convert them into digital data that can be processed by computer. There are different type of optical readers are available. The common type of optical reader are as follows: 

1. Optical Character Recognition

It is technology that you read typewritten, handwritten character from ordinary document, translate the image into a form that can be recognized by computer.

2.  Optical Mark Recognition 

 It is also called mark sensing device also. This device is use light beam to read data. The data is converted into digital signal. The signal are then sent to the computer for further processing.