Example of the scan line effect deliberately applied to an image
PAL video signal scan line. From the left: horizontal sync pulse, back porch with color burst, signal itself, front porch, sync pulse, back porch with color burst, video portion of the next scan line. The signals from multiple lines are overlaid, showing shaded areas instead of a single curve
On CRT screens the horizontal scan lines are visually discernible, even when viewed from a distance, as alternating colored lines and black lines, especially when a progressive scan signal with below maximum vertical resolution is displayed.[2] This is sometimes used today as a visual effect in computer graphics.[3]
The term is used, by analogy, for a single row of pixels in a raster graphics image.[4] Scan lines are important in representations of image data, because many image file formats have special rules for data at the end of a scan line. For example, there may be a rule that each scan line starts on a particular boundary (such as a byte or word; see for example BMP file format). This means that even otherwise compatible raster data may need to be analyzed at the level of scan lines in order to convert between formats.
scan, line, scan, line, also, scanline, line, raster, scanning, pattern, such, line, video, cathode, tube, display, television, computer, monitor, example, scan, line, effect, deliberately, applied, image, video, signal, scan, line, from, left, horizontal, syn. A scan line also scanline is one line or row in a raster scanning pattern such as a line of video on a cathode ray tube CRT display of a television set or computer monitor 1 Example of the scan line effect deliberately applied to an image PAL video signal scan line From the left horizontal sync pulse back porch with color burst signal itself front porch sync pulse back porch with color burst video portion of the next scan line The signals from multiple lines are overlaid showing shaded areas instead of a single curve On CRT screens the horizontal scan lines are visually discernible even when viewed from a distance as alternating colored lines and black lines especially when a progressive scan signal with below maximum vertical resolution is displayed 2 This is sometimes used today as a visual effect in computer graphics 3 The term is used by analogy for a single row of pixels in a raster graphics image 4 Scan lines are important in representations of image data because many image file formats have special rules for data at the end of a scan line For example there may be a rule that each scan line starts on a particular boundary such as a byte or word see for example BMP file format This means that even otherwise compatible raster data may need to be analyzed at the level of scan lines in order to convert between formats See also EditInterlaced video Scanline rendering Flicker screen Stroboscopic effectReferences Edit Keith Jack and Vladimir Tsatsulin 2002 Dictionary of Video and Television Technology Newnes p 242 ISBN 978 1 878707 99 4 Wesley Fenlon 15 January 2014 In Search of Scanlines The Best CRT Monitor for Retro Gaming Tested Gabriel B December 2012 Freeware Friday Maldita Castilla Blistered Thumbs Archived from the original on 2014 02 27 Robin Stuart Ferguson 2001 Practical algorithms for 3D computer graphics A K Peters Ltd p 104 ISBN 978 1 56881 154 3 This video technology article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Scan line amp oldid 1044713423, wikipedia, wiki, book, books, library,
