Bar chart / histogram (Histogram).

Histogram is to understand the key to digital images. .10x4 cell number in the following block diagram, we use color to classify, and pile up. .The higher the stack, shown to belong to the color of the box more. .Therefore, all the color out of the heap with the "histogram" to show a block diagram of the color distribution. .Feature in the sensor, we have in the "sensor" feature in the histogram is to understand about digital images <P> key. .10x4 cell number in the following block diagram, we use color to classify, and pile up. .The higher the stack, shown to belong to the color of the box more. .Therefore, all the color out of the heap with the "histogram" to show a block diagram of the color distribution. .</ P> <P align=center> </ P> <P> topics in the sensor, we have in the "sensor" feature in the mentioned lots of digital images of the same color from the box (ie pixels) .composition, because these boxes are small, they appear to be exactly the same. .If color alone is difficult to distinguish between pixels, the engineers put the pixel brightness by 256 to distinguish from black (0) to white (255), the middle 254 Gray Levels. .As we have just the color of the block diagram of a pile, like image processing software automatically the image brightness by 255 classified, and the "brightness of the box" pile up. .Each "pile" or each "column" to tell us the brightness of the pixels belonging to a certain number of months. .</ P> <P> in the above histogram, each "column" represents a pixel wide. .256 "columns" by the brightness of a pick a different line up closely, there is no gap between them. .The top right of the figure belongs to the nature of teaching to the composition of the image histogram to show the principle. .Histogram of the gap should not exist, because the gap that a gradation (brightness level) of the missing. .Histogram is usually the "column" are in black to the bottom right of the histogram shown above. .</ P> <P align=center> </ P> <P align=center> histogram typical example </ P> <P align=center> </ P> <P align=center> <1> right .exposure images </ P> <P> the graph is an example of a correct exposure, correct exposure of the photo has a "good" histogram. .Smooth the transition curve and landed in the "255" in this position, which reflects the high part of the cloud and the light waves are well restored. .Similarly, the curve from "0" position (dark tone), the curve progression. .</ P> <P align=center> </ P> <P align=center> <2> underexposed images </ P> <P align=center> </ P> <P> most of the above histogram .pixels concentrated in the "0" and close to "0" position, indicating that the photo is underexposed. .By "dynamic range" feature in the description, we know the details of such a dark picture must be suffered serious losses. .We can also see photos of many of the pure black area, a correct image exposure should not have so many black pixels. .In addition, only a small number of pixels describes the high-light areas of the scene. .</ P> <P align=center>.