Home 
The Primers Dot Crawl
The Primers Dot Crawl
|
Dot Crawl Dot Crawl Defined |
All
televisions are subject to a problem called "dot crawl". This shows up
along horizontal or diagonal edges of objects that have  contrasting
colors (for example, yellow adjacent to blue), and looks like a moving
stairway (escalator). It is caused by the imperfect ability of the comb
filter in the TV (or video player) to separate the color signal from
the luminance (brightness) because the frequencies overlap. The amount
of dot crawl varies with the quality of the TV, but also those units
with special image processing features that allow you to enlarge the
picture to fill the screen (in "widescreen" TVs; see below) or to
magnify a part of the image you want to see in more detail, may be
particularly prone to exaggerated dot crawl. Therefore, look for this
artifact when choosing a television, especially those with
sophisticated arrays of image manipulating capabilities.
Comments (0)
 Write comment
 |
Subscribe to this comment's feed
