Task 1 - Technical Glossary
Pixel
In digital imaging, a pixel 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.
Each pixel is a sample of an original image; more samples typically provide more
accurate representations of the original. The intensity of each pixel is variable.
The more pixels used to represent an image, the closer the
result can resemble the original image. The number of pixels in an image is
sometimes called the resolution, though resolution has a more specific definition.
This example shows an image with a
portion greatly enlarged, in which the individual pixels are rendered as small
squares and can easily be seen.
A photograph of sub-pixel display
elements on a laptop's LCD screen
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 a 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.
An image that is 2048 pixels in width and 1536 pixels in
height has a total of 2048×1536 = 3,145,728 pixels or 3.1 megapixels. One could
refer to it as 2048 by 1536 or a 3.1-megapixel image.
File
Formats
Bmp
The BMP file format is also known as bitmap image file format or
simply a bitmap, is a raster graphics image file format used to store bitmap
digital images, The BMP file format is capable of storing 2D digital images of
arbitrary width, height, and resolution, both monochrome and colour, in various
colour depths, and optionally with data compression, alpha channels, and colour
profiles.
Png
Portable Network
Graphics is a Raster graphics file format that supports lossless data
compression. PNG was created as an improved, non-patented replacement for
Graphics Interchange Format (GIF), and is the most used lossless image
compression format on the World Wide Web. PNG
supports palette-based images (with palettes of 24-bit RGB or 32-bit RGBA
colours), grayscale images, and full-colour non-palette-based RGB images. PNG
was designed for transferring images on the Internet, not for
professional-quality print graphics.
Gif
The Graphics Interchange Format is a bitmap image format that supports up to 8 bits per pixel thus allowing a
single image to reference a palette of up to 256 distinct colours. The colours
are chosen from the 24-bit RGB colour space. It also supports animations and
allows a separate palette of 256 colours for each frame. The colour
limitation makes the GIF format unsuitable for reproducing colour photographs
and other images with continuous colour, but it is well-suited for simpler
images such as graphics or logos with solid areas of colour.
Tiff
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
colour depths from 1-bit to 24-bit. Since the original TIFF standard was
introduced, people have been making many small improvements to the format, so
there are now around 50 variations of the TIFF format. Recently, JPEG has
become the most popular universal format, because of its small file size and
Internet compatibility.
Jpeg
JPEG is a compressed
image file format. JPEG images are not limited to a certain amount of colour,
like GIF images are. Therefore, the JPEG format is best for compressing
photographic images. So if you see a large, colourful image on the Web, it is
most likely a JPEG file.
PSD
A PSD file is a layered image file used in Adobe Photoshop.
PSD, which stands for Photoshop Document, is the default format that Photoshop
uses for saving data. PSD is a proprietary file that allows the user to
work with the images’ individual layers even after the file has been saved.
PDF
It Stands for Portable
Document Format. PDF is a multi-platform file format developed by Adobe
Systems. A PDF file captures document text, fonts, images, and even formatting
of documents from a variety of applications. You can e-mail a PDF document to
your friend and it will look the same way on his screen as it looks on yours,
even if he has a Mac and you have a PC. Since PDFs contain colour-accurate
information, they should also print the same way they look on your screen.
EPS
It Stands for
Encapsulated PostScript. EPS is a PostScript image file format that is
compatible with PostScript printers and is often used for transferring files
between various graphics applications. As
the name implies, EPS files contain PostScript code, which is used for storing
font and vector image information.
Ai
Adobe Illustrator
Artwork (AI) is a proprietary file format developed by Adobe Systems for
representing single-page vector-based drawings in either the EPS or PDF formats.
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.
IMAGE
CAPTURE DEVICES
The use of using
digital cameras or scanners to capture images in a digital format. The resulting
files are then further processed to arrive at a final image.
OPTIMISING
Modify to achieve
maximum efficiency in storage capacity or time or cost.
STORAGE
The
professional discipline that involves working with, in or on any aspect of
planning, delivering, operating or supporting for one or more Storage Asset
Items or any and all solutions put in place to deal with such Items.
Sources that I used to help create a technical glossary:
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