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Photo sharing has become big business. CNet has recently announced the acquisition of photo-sharing company called HeyPix that technology will be folded into the photo-sharing service, called Webshots.

A digital camera (or digicam) is a camera that takes video or photos, or digital video recorder and an electronic image sensor. This is the main device used in digital photography. Most of the 21 th century are digital cameras.

Digital cameras can do things film cameras can not: the images on the screen immediately after they are registered to store thousands of images of a single small memory, free space and delete images. Most, including the most compact cameras that can record moving video with sound, as well as still images. Once you can cut and stitch the photos and perform other elementary editing. When you have a GPS receiver built in, and can produce Geotagged photos.
Optical system works as film cameras, typically using a variable aperture lens to focus light on the image pickup device. Aperture and shutter to recognize the right amount of light the display, just like the movie but the image pickup device is an electronic rather than chemical. Most digicams, with the exception of camera phones and a few specialized types of standard tripod screw.

Digital cameras are incorporated into many devices ranging from PDAs and mobile phones called camera phones) to vehicles. Hubble Space Telescope and other astronomical devices are essentially specialized digital cameras.

Image resolution
Digital camera resolution is often limited image sensor (typically CCD or CMOS sensor chip) that turns light into the individual signals to replace the traditional film photography work. The sensor is composed of millions of "buckets" that essentially count the number of photons to reach the sensor. This means that the image sharpness of a sensor, the higher the value of reading pixels. Depending on the physical structure of the sensor, color mixing system can be used, which requires a demosaicing / interpolation algorithm. What are the number of pixels determines the "number of pixels. For example, the image of 640x480 pixels 307.200, or about 307 kilopixels., 3872x2592 pixels image to 10,036,224, or about 10 million pixels.

If these other factors limit the resolution, a larger number of pixels does not improve it, but it can do, and digital images of great inconvenience and / or increase the image noise. Many digital compact cameras has been criticized for excessive points. Sensors can be so small that their 'buckets' can easily overfill; resolution sensor can once again become more than a camera lens can deliver.


At the heart of the digital camera is a CCD or CMOS image sensor.


This digital camera is partly disassembled. The lens assembly (bottom right) is partially removed, but the sensor (top right), still captures a useful picture of the LCD screen (bottom left).
Since the first digital backs were, there were three basic ways to capture an image, each of which is based on the sensor and color filters, the hardware configuration.

The first method is often referred to as "single-shot, depending on how many times the camera's sensor is exposed to light passing through the camera lens. Single-shot capture systems use a single CCD Bayer filter mosaic, or three separate image sensors in a single primary additive colors red, green and blue), are faced with the same image through the beam splitter.
Most of the existing consumer digital cameras use Bayer filter mosaic with optical anti-aliasing filter to reduce aliasing due to the different primary-color images, the reduced sampling. Interpolate color information demosaicing algorithm used to create a full range of RGB video data.
Cameras that use beam-splitter single-shot 3CCD approach, multi-shot three-filter method, color co-site sampling or fovea X3 sensor do not use anti-aliasing filters, nor demosaicing.