Picture resolution is the detail the image has. This term applies to raster digital images, movie images, and other image types. Higher resolution means more image details.
Image resolution can be measured in various ways. Resolution quantifies how close the line can be to each other and still looks resolved . Resolution units may be associated with physical size (eg line per mm, line per inch), to the overall size of the image (line per image height, also known as line, TV line or TVL), or to the corner subtask. Line couples are often used instead of lines; a pair of lines consisting of dark lines and adjacent light lines. Lines are dark lines or thin lines. Resolution of 10 rows per millimeter means 5 alternating dark lines with 5 light lines, or 5 pairs of lines per millimeter (5 LP/mm). Photographic lenses and film resolutions are most often quoted on line pairs per millimeter.
Video Image resolution
Digital image resolution
The resolution of a digital camera can be explained in many ways.
Pixel resolution
The term resolution is often considered to be equivalent to the number of pixels in digital imaging, although international standards in the field of digital cameras specifying it should instead be called "Total Number of Pixels" in relation to the image sensor, and as "Number of Recorded Pixels" for what is completely taken. Therefore, JCIA & amp; CIPA suggests notations such as "Number of Recording Pixels 1000 ÃÆ'â €" 1500 ". According to the same standard, the "Number of Effective Pixels" owned by image sensors or digital cameras is the number of pixel sensors that contribute to the final image (including the pixels not in the image but still supporting the image filtering process), as opposed to total pixels , which include unused or light-shielded pixels around the edges.
High image N pixels with width of M pixels can have resolution less than N line per image height, or N TV line. But when the number of pixels is called "resolution", this convention describes pixel resolution with a set of two positive integers, 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 ÃÆ'â € "6876 . Another popular convention is to cite resolution as the total number of pixels in the image, usually given as the number of megapixels, which can be calculated by multiplying the pixel columns by pixel rows and dividing by one million. Other conventions include describing pixels per unit length or pixels per unit area, such as pixels per inch or per square inch. None of these pixel resolution are true resolutions, but they are widely referred to as such; they serve as the upper limit on image resolution.
Below is an illustration of how the same image might appear at different pixel resolutions, if the pixel is poorly reduced as a sharp box (typically, smoother picture reconstruction of pixels would be preferred, but for pixel illustrations the sharper box makes the point better ).
Images with a width of 2048 pixels and a height of 1536 pixels have a total of 2048ÃÆ'â € "1536 = 3,145,728 pixels or 3.1 megapixels. One could call it a 2048 by 1536 or a 3.1 megapixel image. Or you can think of it as a very low quality image (72ppi) when printed at about 28.5 inches wide, or a very good quality image (300ppi) if printed about 7 inches wide.
Unfortunately, the pixel count is not the true size of the digital camera image resolution, as the color image sensor is usually set to an alternate color filter type on top of the light sensitive individual pixel sensor. Digital images ultimately require red, green, and blue values ​​for each pixel to be displayed or printed, but one individual pixel in the image sensor will supply only one of three pieces of information. Images must be interpolated or demoted to produce all three colors for each output pixel.
Spatial resolution
Spatial resolution in radiology refers to the ability of imaging modalities to distinguish two objects. The low spatial resolution technique will not be able to distinguish between two relatively adjacent objects.
The size of how closely the line can be completed in an image is called spatial resolution, and it depends on the property of the system that creates the image, not just the pixel resolution in pixels per inch (ppi). For practical purposes, the clarity of an image is determined by its spatial resolution, not the number of pixels in an image. As a result, spatial resolution refers to the number of independent pixel values ​​per unit length.
Spatial resolution of computer monitors is generally 72 to 100 lines per inch, corresponding to a pixel resolution of 72 to 100 ppi. With scanners, optical resolution is sometimes used to distinguish spatial resolution from the number of pixels per inch.
In remote sensing, spatial resolution is usually limited by diffraction, as well as by irregularities, incomplete focusing, and atmospheric distortion. The distance of the soil sample (GSD) of an image, the pixel distance on the surface of the Earth, is usually much smaller than the size of the place that can be solved.
In astronomy, one often measures spatial resolution at data points per arcsecond deposited at the observation point, since the physical distance between the objects in the image depends on the distance and this varies greatly with the object of interest. On the other hand, in an electron microscope, the line or periphery of resolution refers to the minimum separation detected between adjacent parallel lines (eg between atomic planes), whereas the point resolution instead refers to the minimum separation between points adjacent. which can be detected and interpreted eg as adjacent columns of atoms, for example. The former often helps one detect periodicity in specimens, while the latter (though more difficult to achieve) is the key to visualizing how individual atoms interact.
In Stereoscopic 3D images, spatial resolution can be defined as spatial information recorded or captured by two stereo camera viewpoints (left and right cameras). The effect of spatial resolution on the overall perceived resolution of an image on a person's mind has not been fully documented. It can be said that such "spatial resolution" can add an image that will not then depend entirely on the number of pixels or Dots per inch alone, when classifying and interpreting the overall resolution of a given video image or frame.
Spectral resolution
Spectral resolution is the ability to solve spectral and ribbon features into separate components. Image colors differentiate different light spectra. The multispectral image resolves the far wider spectrum or wavelength difference than is necessary to reproduce the color. That is, multispectral images have higher spectral resolution than normal color images. The spectral resolution required by the analyst or researcher depends on the application involved. For example, routine analysis for basic sample identification usually requires low/moderate resolution.
Temporary resolution
Temporal resolution (TR) refers to the accuracy of measurements with respect to time. Often there is a trade-off between the temporal resolution of the measurement and the spatial resolution because of the uncertainty principle which is the property attached to the Fourier transform.
Movie cameras and high-speed cameras can complete events at various time points. The time resolution used for movies is usually 24 to 48 frames per second (frame/s), while high-speed cameras can complete 50 to 300 frames/s, or even more.
Many cameras and displays compensate for the relative color components of each other or temporal mixing with spatial resolution:
Radiometric resolution
The radiometric resolution determines how smooth a system can represent or differentiate intensity differences, and is usually expressed as a number of bits or bits, eg 8 bits or 256 levels that are typical of computer image files. The higher the radiometric resolution, the better the intensity or reflective difference that can better be represented, at least in theory. In practice, an effective radiometric resolution is usually limited by the noise level, not by the number of bit representations.
Maps Image resolution
Resolution on various media
This is a list of traditional analog horizontal resolutions for various media. This list only covers the popular format, not the rare format, and all values ​​are approximate, because the actual quality may vary from machine to machine or tape-to-tape. For convenience-benchmarking, all values ​​are for the NTSC system. (For a PAL system, replace 480 with 576.) Analog format usually has fewer chroma resolutions.
- Analog and digital beginning
- 352ÃÆ' â € "240Ã,: Video CD
- 333ÃÆ' â € "480Ã,: VHS, Video8, Umatic
- 350ÃÆ' â € "480Ã,: Betamax
- 420ÃÆ' â € "480Ã,: Super Betamax, Betacam
- 460ÃÆ' â € "480Ã,: Betacam SP, Umatic SP, NTSC (Over-The-Air TV)
- 580ÃÆ' â € "480Ã,: Super VHS, Hi8, LaserDisc
- 700ÃÆ' â € "480Ã,:: Betamax Definition Improvement, Analog Broadcast Limit (NTSC)
- 768ÃÆ' â € "576: Analog broadcast limit (PAL, SECAM)
- Digital
- 500ÃÆ' â € "480 Ã,: Digital8
- 720ÃÆ' â € "480Ã,: D-VHS, DVD, miniDV, Digital Betacam (NTSC)
- 720ÃÆ' â € "480 Ã,: Widescreen DVD (anamorphic) (NTSC)
- 720ÃÆ' â € "576 Ã,: D-VHS, DVD, miniDV, Digital8, Digital Betacam (PAL/SECAM)
- 720ÃÆ' â € "576 Ã,: Widescreen DVD (anamorphic) (PAL/SECAM)
- 1280ÃÆ' â € "720 Ã,: D-VHS, HD DVD, Blu-ray, HDV (miniDV)
- 1440ÃÆ' â € "1080 Ã,: HDV (miniDV)
- 1920ÃÆ' â € "1080 Ã,: HDV (miniDV), AVCHD, HD DVD, Blu-ray, HDCAM SR
- 1998ÃÆ' â € "1080 Ã,: 2K Flat (1.85: 1)
- 2048ÃÆ' â € "1080 Ã,: 2K Digital Cinema
- 3840ÃÆ' â € "2160 Ã,: 4K UHDTV
- 4096ÃÆ' â € "2160 Ã,: 4K Digital Cinema
- 7680ÃÆ' â € "4320 Ã,: 8K UHDTV
- 15360ÃÆ' â € "8640Ã,: 16K Digital Cinema
- 61440ÃÆ' â € "34560Ã,: 64K Digital Cinema
- The order of the newer movies is scanned at 2,000, 4,000, or even 8,000 columns, called 2K, 4K, and 8K, for editing quality visual effects on the computer.
- IMAX, including IMAX HD and OMNIMAX: resolutions around 10,000ÃÆ' â € "7,000 (7,000 lines). It is around 70 Mpix, which is currently the highest resolution digital cinema-sensor camera (as of January 2012).
- Movies
- 35 mm film scanned for release on DVD in 1080 or 2000 lines in 2005.
- The actual resolution of the original negative 35 mm camera is the subject of much debate. The measured resolution of negative films has ranged from 25-200 lp/mm, which is equivalent to the 325 line range for 2-perf, to (theoretically) over 2300 lines for 4-perf shots on the T-Max 100. Kodak states that 35mm Film has a resolution equivalent to 6K according to IMAX Senior Vice President.
- The resolution of modern digital cameras
- Single-format digital media camera, not combining one large digital sensor - 80 Mpix (starting from 2011, currently in 2013) - 10320 × 7752 or 10380 × 7816 (81.1Mpix).
- Mobile - Nokia 808 PureView - 41 Mpix (7728 ÃÆ'â € "5368), Nokia Lumia 1020 - also 41 Mpix (7712 ÃÆ'â €" 5360)
- Digital photo camera - Canon EOS 5DS - 51 Mpix (8688 ÃÆ'â € "5792)
See also
- Screen resolution
- Dots per inch
- Image scanner
- Pixel density
- High dynamic range imagery
- The Kell factor, which typically limits the number of visible lines up to 0.7x from the device resolution
References
External links
Source of the article : Wikipedia
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