1. Pixels
In digital imaging, a pixel, or pel, (picture
element) is a physical point in a raster image, or
the smallest addressable element in a display
device; so it is the smallest controllable element
of a picture represented on the screen
http://en.wikipedia.org/wiki/Pixel

2. A pixel is generally thought of as the smallest single component of a digital
image. However, the definition is highly context-sensitive. For example, there
can be "printed pixels" in a page, or pixels carried by electronic signals, or
represented by digital values, or pixels on a display device, or pixels in a digital
camera (photo sensor elements).
Graphics monitors display pictures by dividing the display screen into
thousands (or millions) of pixels, arranged in rows and columns. The pixels are
so close together that they appear connected.
http://en.wikipedia.org/wiki/Pixel
http://www.webopedia.com/TERM/P/pixel.html

3. Pixel colour depth
Colour depth is defined by how many bits per pixel can be displayed on screen at one time. Each
bit Represents 2 colours because it has a value of either 0 or 1. So basically the More bits to Each
pixel the more amount of colours or shades of one colour can be displayed.
For example:
The number of bits used to represent each pixel determines how many colours or shades of grey
can be displayed. in 8-bit colour mode, the colour monitor uses 8 bits for each pixel, making it
possible to display 2 to the 8th power (256) different colours or shades of grey.
Below are some examples of colours Shown By using a different amount of bits for each pixel:
http://www.webopedia.com/TERM/P/pixel.html
1 bit 4 bits 24 bits (truecolour)

4. Light Converting – Cameras
Instead of using film, digital Cameras use a special Silicone Sensor To convert
light into a electrical charges and then a digital image. These Sensors have
millions of ‘’photosites’’ on them (often called pixels) that are sensitive to
light.

5. Resolution
Resolution means How sharp an image is and is most often used in Monitors
and Bit-mapped Graphic image.
Bitmapped images are Composed of pixels, Resolution is the number of pixels
per inch of the image (ppi)
Two Aspects of a Bitmapped image that Determine the number of pixels in an
are The size (width and height in inches) and the Resolution ( the amount of
pixels per inch)
The more pixels that are in an image the more Detail can be displayed
properly. The few the pixels the less detail.

6. Screen Ratio
It is commonly expressed as two numbers separated by a colon, as in 16:9. For an
x:y aspect ratio, no matter how big or small the image is, if the width is divided
into x units of equal length and the height is measured using this same length
unit, the height will be measured to be y units. For example, consider a group of
images, all with an aspect ratio of 16:9. One image is 16 inches wide and 9 inches
high. Another image is 16 centimetres wide and 9 centimetres high. A third is 8
yards wide and 4.5 yards high.
The most common aspect ratios used today in the presentation of films in movie
theatres are 1.85:1 and 2.39:1.Two common videographic aspect ratios are 4:3
(1.33:1), the universal video format of the 20th century, and 16:9
(1.77:1), universal for high-definition television and European digital television.
Other cinema and video aspect ratios exist, but are used infrequently.
http://en.wikipedia.org/wiki/Aspec
t_ratio_(image)

7. Frame Rate
The frame-rate says how many images of a movie are
displayed every second a movie is played.
The higher frame rate a movie has the smoother objects
move in the movie.
Compare a movie with low frame rate with a movie with
higher frame rate. The movie with high frame has more
frames for the same number of seconds film. The movie
with higher frame rate will also be stored in a larger file.
You measure frame rate in frames per seconds (fps).
Frame rate in game is the same thing. The only difference
between movie frames and game frames are that movie
frames are created as you play for a movie they are just
recreated from a file.
A constant frame rate is desired for smooth playback.
Depending on the compression used in the video file it can
put a heavy load on your computer. If the computer is not
able to replay the movie at the frame rate it was encoded
for it will either stutter and slowdown or drop frames will be
dropped.
http://www.fastvideoindex
er.com/knowledgebase/fra
merate.html

8. Video Formats and compression
A video format defines the way in which a video is recorded and stored.
It normally specifies
Code/compression
Frame Rate
Frame size
Frame Aspect Ratio
Pixel Aspect Ratio
Scanning Method.
Common formats are DV, HDV and AVCHD.
Compression is The way that date is encoded into the file and
Decoded when played back. There are two Types of Codec
(compressor) A lossy codec or a lossless codec. A lossy codec will
Throw away data and the final video will be of less quality but with a
smaller file size Whereas a lossless codec will keep all data and will
Result in a higher quality final video but with a much larger file size
Advanced Coding High Definition
(developed by sony and Panasonic in 2006)
Launched in 1995 for storing
digital video
HDV is a format for recording of high-definition video
on DV cassette tape. The format was originally
developed by JVC and supported by Sony, Canon and
Sharp. The four companies formed the HDV
consortium in September 2003.