Download Image and Sound Editing

Image and Sound Editing
Raed S. Rasheed
2012
Image
• Image.
• Digital image.
– Raster images.
– Vector Images.
– Stereo Images.
– Image File Formats
• Lossless compression
• Lossy compression
Image
• An image: is an artifact, that has a similar
appearance to some subject - usually a
physical object or a person.
– 2-D such as a photograph, screen display, and
– 3-D such as a statue or hologram.
Digital Image
• An digital image: is a numeric representation
(normally binary) of a 2-D image. Depending
on whether the image resolution is fixed, it
may be of vector or raster type.
• "digital image" usually refers to raster images
also called bitmap images.
• (Raster, Vector, and Stereo) Images.
Digital Image
Digital Image
Raster Images
• Raster images have a finite set of digital
values, called picture elements or pixels.
• The digital image contains a fixed number of
rows and columns of pixels.
• Pixels are the smallest individual element in
an image, holding quantized values that
represent the brightness of a given color at
any specific point.
Raster Images
• Raster image type
– Binary: is a digital image that has only two
possible values for each pixel.
– Grayscale: is an image in which the value of each
pixel is a single sample, that is, it carries only
intensity information.
– Color: is a digital image that includes color
information for each pixel.
Raster Images
Vector Images
• Vector images resulted from mathematical
geometry (vector). In mathematical terms, a
vector consists of point that has both direction
and length.
• Often, both raster and vector elements will be
combined in one image; for example, in the
case of a billboard with text (vector) and
photographs (raster).
Stereo Images
• Stereoscopy (also called stereoscopic or 3-D
imaging) refers to a technique for creating or
enhancing the illusion of depth in an image by
presenting two offset images separately to the
left and right eye of the viewer. These 2-D
images are then combined in the brain to give
the perception of 3-D depth.
Image File Formats
• Image file formats are standardized means of
organizing and storing digital images. Image
files are composed of either pixels, vector
(geometric) data, or a combination of the two.
Image File Formats
• Image file compression
– Lossless compression algorithms reduce file size
without losing image quality, though they are not
compressed into as small a file as a lossy compression
file.
– Lossy compression algorithms take advantage of the
inherent limitations of the human eye and discard
invisible information. Most lossy compression
algorithms allow for variable quality levels
(compression) and as these levels are increased, file
size is reduced.
Image File Formats
• Raster formats
– JPEG/JFIF JPEG (Joint Photographic Experts Group)
is a compression method JPEG compression is (in
most cases) lossy compression.
– TIFF (Tagged Image File Format) format is a
flexible format that normally saves 8 bits or 16 bits
per color (red, green, blue) for 24-bit and 48-bit
totals. Can be lossy and lossless.
– GIF (Graphics Interchange Format) is limited to an
8-bit palette, or 256 colors.
Image File Formats
• Raster formats
– PNG (Portable Network Graphics) file format was
created as the free, open-source successor to the GIF.
Supports truecolor (16 million colors).
– BMP (Windows bitmap) handles graphics files within
the Microsoft Windows OS. Typically, BMP files are
uncompressed, hence they are large; the advantage is
their simplicity and wide acceptance in Windows
programs.
– WebP is a new image format that uses lossy
compression. It was designed by Google to reduce
image file size to speed up web page loading
Image File Formats
• Raster formats
– JPEG XR (New JPEG standard based on Microsoft HD
Photo)
– TGA (TARGA)
– ILBM (InterLeaved BitMap)
– IMG (Graphical Environment Manager image file;
planar, run-length encoded)
– PCX (Personal Computer eXchange)
– ECW (Enhanced Compression Wavelet)
– IMG (ERDAS IMAGINE Image)
Image File Formats
• Raster formats
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SID (multiresolution seamless image database, MrSID)
CD5 (Chasys Draw Image)
FITS (Flexible Image Transport System)
PGF (Progressive Graphics File)
XCF (eXperimental Computing Facility format, native
GIMP format)
– PSD (Adobe PhotoShop Document)
– PSP (Corel Paint Shop Pro)
Image File Formats
• Vector formats
– CGM (Computer Graphics Metafile) is a file format
for 2D vector graphics.
– SVG (Scalable Vector Graphics) is an open
standard created and developed by the W3C.
Image File Formats
• Stereo formats
– MPO (Multi Picture Object) (.mpo) format consists
of multiple JPEG images (Camera & Imaging
Products Association) (CIPA).
– PNS PNG Stereo (.pns) format consists of a sideby-side image based on PNG (Portable Network
Graphics).
– JPS JPEG Stereo (.jps) format consists of a side-byside image format based on JPEG.