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From Wikipedia

Image analysis

Image analysis is the extraction of meaningful information from images; mainly from digital images by means of digital image processing techniques. Image analysis tasks can be as simple as reading bar coded tags or as sophisticated as identifying a person from their face.

Computers are indispensable for the analysis of large amounts of data, for tasks that require complex computation, or for the extraction of quantitative information. On the other hand, the human visual cortex is an excellent image analysis apparatus, especially for extracting higher-level information, and for many applications — including medicine, security, and remote sensing — human analysts still cannot be replaced by computers. For this reason, many important image analysis tools such as edge detectors and neural networks are inspired by human visual perception models.

Computer image analysis

Computer image analysis largely contains the fields of computer or machine vision, and medical imaging, and makes heavy use of pattern recognition, digital geometry, and signal processing. This field of computer science developed in the 1950s at academic institutions such as the MIT A.I. Lab, originally as a branch of artificial intelligence and robotics.

It is the quantitative or qualitative characterization of two-dimensional (2D) or three-dimensional (3D) digital images. 2D images are, for example, to be analyzed in computer vision, and 3D images in medical imaging. The field was established in the 1950s—1970s, for example with pioneering contributions by Azriel Rosenfeld, Herbert Freeman, Jack E. Bresenham, or King-Sun Fu.


There are many different techniques used in automatically analysing images. Each technique may be useful for a small range of tasks, however there still aren't any known methods of image analysis that are generic enough for wide ranges of tasks, compared to the abilities of a human's image analysing capabilities. Examples of image analysis techniques in different fields include:

Digital image analysis

Digital Image Analysis is when a computer or electrical device automatically studies an image to obtain useful information from it. Note that the device is often a computer but may also be an electrical circuit, a digital camera or a mobile phone. The applications of digital image analysis are continuously expanding through all areas of science and industry, including:

Object-based image analysis

Object-Based Image Analysis (OBIA) is a sub-discipline of sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth. The human eye can distinguish about 10 million colors.

In common with the eyes of other mammals, the human eye's non-image-forming photosensitive ganglion cells in the retina receive the light signals which affect adjustment of the size of the pupil, regulation and suppression of the hormone melatonin and entrainment of the body clock.

General properties

The eye is not properly a sphere, rather it is a fused two-piece unit. The smaller frontal unit, more curved, called the cornea is linked to the larger unit called the sclera. The corneal segment is typically about 8 mm (0.3 in) in radius. The sclera constitutes the remaining five-sixths; its radius is typically about 12 mm. The cornea and sclera are connected by a ring called the limbus. The iris – the color of the eye – and its black center, the pupil, are seen instead of the cornea due to the cornea's transparency. To see inside the eye, an ophthalmoscope is needed, since light is not reflected out. The fundus (area opposite the pupil) shows the characteristic pale optic disk (papilla), where vessels entering the eye pass across and optic nerve fibers depart the globe.


The dimensions differ among adults by only one or two millimeters. The vertical measure, generally less than the horizontal distance, is about 24 mm among adults, at birth about 16–17 mm. (about 0.65 inch) The eyeball grows rapidly, increasing to 22.5–23 mm (approx. 0.89 in) by the age of three years. From then to age 13, the eye attains its full size. The volume is 6.5 ml (0.4 cu. in.) and the weight is 7.5 g. (0.25 oz.)


The eye is made up of three coats, enclosing three transparent structures. The outermost layer is composed of the cornea and sclera. The middle layer consists of the choroid, ciliary body, and iris. The innermost is the retina, which gets its circulation from the vessels of the choroid as well as the retinal vessels, which can be seen in an ophthalmoscope.

Within these coats are the aqueous humor, the vitreous body, and the flexible lens. The aqueous humor is a clear fluid that is contained in two areas: the anterior chamber between the cornea and the iris and exposed area of the lens; and the posterior chamber, behind the iris and the rest. The lens is suspended to the ciliary body by the suspensory ligament (Zonule of Zinn), made up of fine transparent fibers. The vitreous body is a clear jelly that is much larger than the aqueous humor, and is bordered by the sclera, zonule, and lens. They are connected via the pupil.

Dynamic range

The retina has a static contrast ratio of around 100:1 (about 6½ f-stops). As soon as the eye moves (saccades) it re-adjusts its exposure both chemically and geometrically by adjusting the iris which regulates the size of the pupil. Initial dark adaptation takes place in approximately four seconds of profound, uninterrupted darkness; full adaptation through adjustments in retinal chemistry (the Purkinje effect) are mostly complete in thirty minutes. Hence, a dynamic contrast ratio of about 1,000,000:1 (about 20 f-stops) is possible. The process is nonlinear and multifaceted, so an interruption by light merely starts the adaptation process over again. Full adaptation is dependent on good blood flow; thus dark adaptation may be hampered by poor circulation, and vasoconstrictors like alcohol or tobacco.

The eye includes a lens not dissimilar to lenses found in optical instruments such as cameras and the same principles can be applied. The pupil of the human eye is its aperture; the iris is the diaphragm that serves as the aperture stop. Refraction in the cornea causes the effective aperture (the entrance pupil) to differ slightly from the physical pupil diameter. The entrance pupil is typically about 4 mm in diameter, although it can range from 2 mm () in a brightly lit place to 8 mm () in the dark. The latter value decreases slowly with age, older people's eyes sometimes dilate to not more than 5-6mm.

Field of view

The approximate field of view of a human eye is 95° out, 75° down, 60° in, 60° up. About 12–15° temporal and 1.5° below the horizontal is the optic nerve or blind spot which is roughly 7.5° high and 5.5° wide.

Eye irritation

Eye irritation has been defined as “the magnitude of any stinging, scratching, burning, or other irritating sensation from the eye�. It is a common problem experienced by people of all ages. Related eye symptoms and signs of irritation are e.g. discomfort, dryness, excess tearing, itching, grating, sandy sensation, smarting, ocular fatigue, pain, scratchiness, soreness, redness, swollen eyelids, and tiredness, etc. These eye symptoms are reported with intensities from severe to less severe. It has been suggested that these eye symptoms are related to different causal mechanisms.

Several suspected causal factors in our environment have been studied so far. One hypothesis is that indoor air pollution may cause eye and airway irritation. Eye irritation depends somewhat on destabilization of the outer-eye tear film, in which the formation of dry spots results in such ocular discomfort as dryness. Occupational factors are also likely to influence the perception of eye irritation. Some of these are lighting (glare and poor contrast)

From Yahoo Answers

Question:Any Dr. prepared to give me "scanner" images of human LIMBS? I am doing some preliminary research on "Morphology Replication of Human Limbs Prosthesis". In (very) short: - A human lost an arm - I scan the remaining one - I make a mirror image of it. - I build the missing bones in titanium alloy (technically modified) - I build the muscle structure using nanotube carbon fibres - I build the skin tissue using DNA "spray"... ... more ... - A surgeon "implants" the prothesis. Already a 20 years dream. Accepted as a PhD researcher with Coimbra University. Need concrete preliminary results to confirm research project. Current problems: - Get scanned image of human "arm" (from mid-humerus to finger tips), taken from standard medical scanners to convert these images into 3D models, where the exact sketelton can be extracted in 3D. - Get existing programs that do the transformation (none found yet: medical scanners manufacturers are not prepared to share data) - I can write and develop the program to do the conversion. - Drs. use "Patient confidentiality" to refuse my request. - I offer "my arm" for scanning, but I have to pay for it (tooooo much $) Offers? Solutions? Images? Thanks (I'll put my research status on my site (http://www.web2coders.com/research - in a day or two, if I receive any answer)

Answers:You might get more response if you go visit a clinic or hospital in person. Few of us here in "Computers & Internet" will have access to pictures of people's arms.

Question:I'm trying to find male and female reference images for 3D modelling. I need a standing front and side view. Turnarounds would be great. Any help is appreciated.

Answers:http://www.posemaniacs.com/blog/pose/ This is the site that is recommended to video game character designers to take poses from. It is absolutely awesome. Click on a pose to make it large and rotate it. Screenshot to save.


Answers:He sure didn't patent it on any reptile Perish the thought

Question:Hello I am trying to find out what method or methods are used to show 3D or slices of brain that show the electrical activity. Can you list these. CREED

Answers:well.... their is no vissual instrument out there that can measure the "electrical" activity of the brain, our 3 most sensitive methods for in vivo imaging is MRI, fMRI, and PET. MRI (magnetic resonance imaging) and fMRI work very similar, by detecting what is known as the BOLD signal. Basically they emasure higher activities of blood flow by picking up the iron in blood and spinning the associated electrons of the water molecules in the area (it gets more technical than that). PET (positron emission tomography) is another method of imaging involving the use of radiotracer chemicals. Basically you are treated with low level radiation molecules which either have a non specific (F18- glucose) or can be specific in order to vissualize a type of tissue or cell density (c11 raclopride for vissualization of dopamine neurons in parkinsons patients). Both techniques are able to make 3D images based on the way photographs are taken. basically the vissual software takes thousands of pictures (really readings from detected material either electron spin energy or PET emissions) which can be constructed to form a 3D image. Electrical activity can only be picked up through probes that are measuring alpha, theta, and gamma frequencies given off by the brain, or by electrophysiology probes (however i am not aware of many human protocols for these instruments). Electrophysiology probes are actually inserted into the brain area of interest where it can pick up a field of electrical potential, but to my knowledge most of this work is done in animals.

From Youtube

MAGNETIC RESONANCE IMAGING :-Magnetic resonance imaging (MRI), or Nuclear magnetic resonance imaging (NMRI), is primarily a medical imaging technique most commonly used in radiology to visualize the structure and function of the body. It provides detailed images of the body in any plane. MRI provides much greater contrast between the different soft tissues of the body than computed tomography (CT) does, making it especially useful in neurological (brain), musculoskeletal, cardiovascular, and oncological (cancer) imaging. Unlike CT, it uses no ionizing radiation, but uses a powerful magnetic field to align the nuclear magnetization of (usually) hydrogen atoms in water in the body. Radiofrequency fields are used to systematically alter the alignment of this magnetization, causing the hydrogen nuclei to produce a rotating magnetic field detectable by the scanner. This signal can be manipulated by additional magnetic fields to build up enough information to construct an image of the body. MRI is a relatively new technology, which has been in use for little more than 30 years (compared with over 110 years for X-ray radiography). The first MR Image was published in 1973 and the first study performed on a human took place on July 3, 1977. Magnetic resonance imaging was developed from knowledge gained in the study of nuclear magnetic resonance. In its early years the technique was referred to as nuclear magnetic resonance imaging (NMRI). However, as the word nuclear was associated in the public mind with ...

ASTER Satellite Images :ASTER is one of the five state-of-the-art instrument sensor systems on-board Terra a satellite launched in December 1999. To read more on the ASTER satellite go here www.satimagingcorp.com - The ASTER satellite was built by a consortium of Japanese government, industry, and research groups. ASTER monitors cloud cover, glaciers, land temperature, land use, natural disasters, sea ice, snow cover and vegetation patterns at a spatial resolution of 90 to 15 meters. The multispectral images obtained from this sensor have 14 different colors, which allow scientists to interpret wavelengths that cannot be seen by the human eye, such as near infrared, short wave infrared and thermal infrared. ASTER is the only high spatial resolution instrument on Terra that is important for change detection, calibration and/or validation, and land surface studies. ASTER data is expected to contribute to a wide array of global change-related application areas, including vegetation and ecosystem dynamics, hazard monitoring, geology and soils, land surface climatology, hydrology, land cover change, and the generation of digital elevation models (DEMs). Satellite Imaging Corporation (SIC) is an official distributor for ASTER Imagery through USGS. The ASTER instrument consists of three separate instrument subsystems: VNIR (Visible Near Infrared), a backward looking telescope which is only used to acquire a stereo pair image SWIR (ShortWave Infrared), a single fixed aspheric refracting telescope TIR ...