1. Pixel resolution
The term resolution is often used for a pixel count in digital imaging, even though American,
Japanese, and international standards specify that it should not be so used, at least in the
digital camera field. An image of N pixels high by M pixels wide can have any resolution less
than N lines per picture height, or N TV lines. But when the pixel counts are referred to as
resolution, the convention is to describe the pixel resolution with the set of two positive
integer numbers, where the first number is the number of pixel columns (width) and the
second is the number of pixel rows (height), for example as 7680 by 4320. Another popular
convention is to cite resolution as the total number of pixels in the image, typically given as
number of megapixels, which can be calculated by multiplying pixel columns by pixel rows
and dividing by one million. Other conventions include describing pixels per length unit or
pixels per area unit, such as pixels per inch or per square inch. None of these pixel
resolutions are true resolutions, but they are widely referred to as such; they serve as upper
bounds on image resolution.
According to the same standards, the number of effective pixels that an image sensor or
digital camera has is the count of elementary pixel sensors that contribute to the final
image, as opposed to the number of total pixels, which includes unused or light-shielded
pixels around the edges.
Below is an illustration of how the same image might appear at different pixel resolutions, if
the pixels were poorly rendered as sharp squares (normally, a smooth image reconstruction
from pixels would be preferred, but for illustration of pixels, the sharp squares make the
point better).
VECTOR AND RASTER IMAGES
Raster Graphics (commonly called bitmap images) are made of pixels. Photographs are
an example of a bitmap image. They have a fixed resolution and cannot be resized
larger without losing quality.
Common bitmap file formats end in: .gif .jpg .png .tiff & .bmp
Bitmap images typically have much larger file sizes than the same image as a vector
graphic so they are often compressed to reduce their size. Bitmap images can be
converted from one format to another with programs such as Photoshop.
Vector Graphics are images that have been created in a drawing program such as
Adobe Illustrator. They use paths to create lines and curves at connecting points
called "nodes" to store the graphic's information mathematically. Vector art is
resolution independent; whether you enlarge or shrink the image, the output quality
is never compromised. This is why logos should always be created in vector art
format. Common file formats for vector art used in the commercial printing industry
include: .ai .eps & .pdf

2. BMP - Short for "Bitmap." It can be pronounced as "bump," "B-M-P," or simply a "bitmap image." The BMP
format is a commonly used raster graphic format for saving image files. It was introduced on the Windows
platform, but is now recognized by many programs on both Macs and PCs.
PNG - which can be pronounced "ping" or "P-N-G," is a compressed raster graphic format. It is commonly used
on the Web and is also a popular choice for application graphics.
GIF -The letters "GIF" actually stand for "Graphics Interchange Format," but you don't need to remember that.
What you should know is that a GIF is a compressed image file format. GIF images use a compression formula
originally developed by CompuServe.
TIFF - Stands for "Tagged Image File Format." It is graphics file format created in the 1980's to be the standard
image format across multiple computer platforms. The TIFF format can handle color depths ranging from 1-bit
to 24-bit.
JPG - The term actually stands for "Joint Photographic Experts Group," because that is the name of the
committee that developed the format. But you don't have to remember that because even computer nerds
will think you're weird if you mention what JPEG stands for. Instead, remember that a JPEG is a compressed
image file format.
PSD - Image file created by Adobe Photoshop, a professional image-editing program; may include image layers,
adjustment layers, layer masks, annotation notes, file information, keywords, and other Photoshop-specific
elements.
PDF - Cross-platform document created by Adobe Acrobat or a program with the Acrobat plug-in; commonly
used for e-mail attachments or for saving publications in a standard format for viewing on multiple computers;
usually created from another document instead of from scratch; can be edited with Adobe Acrobat, a
commercial program.
EPS - PostScript (.PS) file that may contain 2D vector graphics, bitmap images, and text; may also include an
embedded preview image in bitmap format; can be placed within another PostScript document.
AI - Drawing created with Adobe Illustrator, a vector graphics editing program; composed of paths connected
by points, rather than bitmap image data; commonly used for logos and print media.
COMPRESSION
Compression, or "data compression," is used to reduce the size of one or more files. When a
file is compressed, it takes up less disk space than an uncompressed version and can be
transferred to other systems more quickly. Therefore, compression is often used to save
disk space and reduce the time needed to transfer files over the Internet.
There are two primary types of data compression:
1. File Compression
2. Media Compression
File compression can be used to compress all types of data into a compressed archive. These
archives must first be decompressed with a decompression utility in order to open the
original file(s). Media compression is used to save compressed image, audio, and video files.
Examples of compressed media formats include JPEG images, MP3 audio, and MPEG video

3. files. Most image viewers and media playback programs can open standard compressed file
types directly.
VIDEO CAPTURE DEVICES
Converting analog video signals, such as those generated by a video camera, into a digital
format and then storing the digital video on a computer's mass storage device. Video
capture from analog devices requires a special video capture card that converts the analog
signals into digital form and compresses the data. There are also digital video devices that
can capture images and transfer them to a computer via a standard serial or parallel
interface.
OPTIMISING
For imagery, optimisation involves choosing a suitable graphic compression format.
Compression reduces the image filesize and consequently the time it takes to download and
display in a browser. Common compression types include GIF, JPEG and PNG. Many
compression formats reduce filesize by removing information from the image
(downsampling). For example, the JPEG format reduces overall tonal range to reduce
filesize—reducing the tonal range means that highlights and shadows become less
pronounced.
Reducing the number, and filesize of the images can be a significant issue for websites with
large subscriber bases such as news sites. Site owners are charged for the amount of
information (data) downloaded from their sites (traffic). The more popular the site and
larger the images the greater the traffic costs.
STORAGE AND ASSET MANAGEMENT
STORAGE AND ASSET MANAGEMENT
Digital asset management (DAM) consists of management tasks and decisions surrounding
the ingestion, annotation, cataloguing, storage, retrieval and distribution of digital assets.
Digital photographs, animations, videos and music exemplify the target areas of media asset
management (a sub-category of DAM).
Digital asset management systems (DAMS) include computer software and hardware
systems that aid in the process of digital asset management.
The term "digital asset management" (DAM) also refers to the protocol for downloading,
renaming, backing up, rating, grouping, archiving, optimizing, maintaining, thinning, and
exporting files.
The "media asset management" (MAM) sub-category of digital asset management
mainlyaddresses audio, video and other media content. The more recentconcept of

4. enterprise content management (ECM) often deals with solutions which address similar
features but in a wider range of industries or applications.