Fully Automated Camera System

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BY: E.Spurthi A.Pallavi Ch.Harika K.Sowmya











Camera records and stores images which may be still images or moving images such as videos or movies They may work with the light of the visible spectrum or with other portions of electromagnetic spectrum It has an aperture at the front for the light to enter and a recording surface at the rear to focus the light 20th century cameras used photographic film as the recording surface where as the new ones are using image sensors Digital cameras have become the norm today with resolution up to 20 megapixels compared to 1 – 1.5 MP of the 1st digital camera.











Captures the light from the subject and brings it to a focus on the film or detector Design and manufacture determines the quality of the photograph They come in various range of focal lengths from extreme wide angle, wide angle, standard, medium telephoto and telephoto Extreme wide angle for architecture due to its capability to capture wide view The telephoto lens is for sports or wildlife









Due to optical properties of photographic lenses, only objects from the limited range of distances from the camera will be produced clearly The simplest cameras have fixed focus and use a small aperture and wide angled lens to ensure that everything within a range of distance from the lens is in reasonable focus Rangefinder cameras allow the distance to objects to be measured by means of a coupled parallax unit on top of the camera Digital single lens reflex cameras determine the focus visually by using objective lens and moving mirror to project image onto ground glass









The size of the aperture and brightness of the scene controls the amount of light that enters the camera during a period of time The shutter controls the length of time for which the light hits the recording surface Large apertures with faster shutter speed and corresponding small apertures with shutter speed slowed down give equivalent exposure The shutters can be either mechanical or electronic or both

It takes the video or still photographs by recording images via an electronic image sensor  The image pick up device is electronic here rather than chemical as in film cameras  Electronic shutter controls the exposure time on the light sensor electronically  Both CMOS and CCD image sensors can be constructed to give a shutter equivalent function








Digital cameras use an electronic image sensor usually a CCD or a CMOS sensor to capture CCD image sensor is an analog device. When light strikes the chip it is held as a small electrical charge in each photo sensor. The charges are converted to voltage one pixel at a time as they are read from the chip. Additional circuitry in the camera converts the voltage into digital information. The CCD sensors create high-quality images as compared to those created by CMOS sensors



A CMOS imaging chip is a type of active pixel sensor made using the CMOS semiconductor process. Extra circuitry next to each photo sensor converts the light energy to a voltage. Additional circuitry on the chip may be included to convert the voltage to digital data.



CCD image sensors are widely used in professional, medical, and scientific applications where high-quality image data is required. CMOS sensors are most commonly in cell phone cameras, web cams and in some DSLRs

Interline transfer CCD image sensors:  Each and every pixel has a charge storage area, which is masked, next to the light sensitive pixel area.  These form vertical column to the bottom of the sensor to transport the pixels down and out the bottom of the sensor.  The row of pixels from the bottom of the sensors is clocked down to a shift register from where it is fed to amplifiers which convert charge to voltage





It is then conditioned and digitized and fed out the back of the camera. Interline transfer CCD interlaced:

Sensor consists of the pixel from each field connected through the Xsg switch to a storage pixel area in the vertical CCD. From here the collected charge is shifted to the horizontal CCD and read out line by line as a video signal. With frame integration the charge from field 1 is transferred to the vertical CCD by Xsg1 and read out as first field. Then the charge from field 2 is read out as field 2. The result is an interlaced frame.

Interline transfer CCD-Progressive scan:  Similar to interlaced but here, from the vertical CCD, the collected charge can be shifted to either one or two horizontal CCD registers. Some sensors allow for two outputs and so with two vertical shifts per line a field is available from the two video outputs. The two outputs are then combined in a frame grabber to a full progressive frame image. The frame rate is double that from a single output


INTERLINE CCD INTERLACED

INTERLINE CCD PROGRESSIVE SCAN





They capture a full frame in a single shutter (integration) period. They differ from Interline Transfer CCDs because they do not have a pixel storage area next to the active pixel and instead have a duplicate sensor used for storage below the active sensor.





The image capture starts with integration period where pixels collect electrons that are converted from photons. It has the advantage of 100 % fill factor and they require half as much pixel area as frame sensors









Each of the pixels has a “photosite” which is uncovered to collect and store photons in a cavity. Once the exposure finishes, the camera closes each of these, assess how many photons fell into each to decide intensity levels. Each cavity has a filter placed over it which only allows a particular colour of light, the common type being “bayer array” which consists of alternative rows of redgreen and green-blue filters. Bayer demosaicing is the process of translating bayer array of primary colours into a final image which contains full colour information at each pixel.





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Focal length is the distance between the lens and the surface of the sensor and this length. On increasing it, the image is magnified and the objects appear to be closer and the reverse happens on decreasing the focal length. Digital cameras provide both digital and optical zoom. Optical zoom lenses modify the focal length of the lens instead of just magnifying the information that hits the sensor. Digital zoom forms a full-size image by interpolating the pixels from the center of the image sensor. This may lead to an output of grainy or blurry images but that depends on the resolution of the image.









Most digital cameras have an LCD screen display, which enables to view the picture. Previously, digital cameras used to have fixed storage inside the camera and the images were transferred by connecting the camera to a computer. Most of today's cameras use removable storage like memory sticks which are of removable flash memory card format. The images are usually stored in TIFF, which is an uncompressed format or JPEG, which is a compressed format and some use RAW format.







Film Processing: No longer do you have to waste the time and energy in developing the roll of film in a dark room. With digital cameras, we simply can transfer image to computer using the camera's data cable. Massive Photo Storage: Digital cameras can easily store up to 10,000 photos, depending on the size of the memory card. This completely outweighs the storage capacity of traditional roll film cameras. Operating Speed: In case of earlier cameras, one always had to wind the film after clicking a photograph. inconvenience. No such activity is required in case of digital cameras.

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Face Detection: High-end digital cameras have been meticulously designed for face detection through the camera lens. Hence we could say goodbye to all those blurry faces and red-eye photographs. Motion Detection: These days, high-end digital cameras also come equipped with inbuilt motion detection mechanisms which adjust moving images and thereby avoid blurriness. This becomes particularly useful when taking pictures of moving objects: a horse race or a football match in progress. Night Modes: Clicking pictures in the dark or in dim-lit surroundings has become much easier, with night mode features that are commonly available in today's digital cameras.

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Viewing Screens: Digital cameras have viewing screens on the camera body which allow you to view the image as soon as you have clicked it. If you do not like it, you can simply delete it then and there Waterproof: These days, there are many waterproof digital cameras which allow you to indulge in underwater photography. Total VFM: Digital cameras are extremely costeffective, adaptable, and offer total VFM (value for money). Besides, they are constantly being upgraded with new features, thanks to continuous technological advances.

 PIR

Motion Sensors: Passive

infrared  Detectors of warm bodied targets in motion.  Also detects bodies temperature less than ambient temperature.  Some undesired operations

Self recording surveillance Camera  Detects people moving around and starts recording  High resolution mode of 640 X 480 pixels for every 3.5 or 4 seconds  1gb card stores 50,000 colour frames




Detects obstacles Gives signal in audio form to the owner Avoids accidents





IP cameras makes the detection of audio bit simpler  Detects emergency situations and makes sense of other events  Audio covers 360 degrees view coverage is extended beyond the field of view  Audio detection can trigger email, or other alerts automatically direct camera to record.


Thank you 

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