How Do I Choose the Best Histogram Software?

Starting from Photoshop CS, Adobe has added a histogram palette. Before that, if you want to observe the histogram of an image, you need to open the "Histogram" command under the "Image" menu, or Only in the dialog box can you see the image histogram. For images, there are almost no identical histograms, and each image is unique, so the histogram of each image is also unique. ^[1]

Histogram

(One of the computer graphics image software photoshop panels)

The histogram graphically represents the number of pixels at each brightness level of the image and shows the distribution of pixels in the image. The histogram shows details in the shadows (shown in the left part of the histogram), midtones (shown in the middle), and highlights (shown in the right part). Histograms help users determine if an image has enough detail to make a good correction. ^[1]

Compact view

In Photoshop CS, the histogram palette and information palette are arranged together with the photoshop navigation map palette to form a palette group. The histogram palette displays the gradation information of an image, ^[2]

The shape of the histogram is diverse, and the diverse shapes change as the image is adjusted. Observing the RGB histogram of the image, you will find that there is a very sharp spike in the dark tone area on the left side of the histogram. This shows that a large number of pixels are clustered in a narrow range of color levels, and the difference in color levels between these pixels is very small, resulting in insufficient texture and detail in the area. ^[1]

normal

"Normal" histogram means that the histogram of the image's histogram has a more uniform morphological distribution. The pixel gradation of this type of image is distributed within the full gradation range, and there are no sharp and abrupt peaks on the histogram. The "normal" histogram is the most common form of histogram in RGB mode. A "normal" histogram is just a common form of a histogram. The "normal" is for the "abnormal". The "normal" does not mean "normal". Some images with the "normal" histogram form are not normal. Conversely, an image with an "abnormal" histogram is not necessarily abnormal. ^[4]

"L" shape

"L" shaped histograms are abnormal histograms. Images with "L" shaped histograms are basically dark-tone images. The dark-tone areas of the image are clustered with a large number of pixels, and there are few pixels in the highlights and intermediate tones. The histogram has a large number of dark-tone areas. Pixel spikes, the overall shape is like the capital letter "L" ^[5]

" J " shape

Corresponding to the "L" shaped histogram is the "J" shaped histogram. Contrary to the L -shaped histogram, the peaks of the J -shaped histogram are located on the right side (highlight area) of the histogram, which is basically a highlight image. ^[6]

"" shape

The peak position of the -shaped histogram is located in the center (halftone) of the histogram. The image with this histogram often has a large halftone background. If the histogram spikes of the individual color channels are staggered, the midtones of this block have a certain color. As shown in the figure, the histogram of the "red" channel is "L", and the "green" channel and the "blue pass" channel are "". The staggered peaks create the turquoise background of the image. The bulge indicates the red leaf area of the image. ^[6]

"" shape

The peaks of the "" shape histogram are concentrated in the middle area (middle gradation level) of the histogram, but rarely distributed in the dark and highlight areas. Because the pixel level is not distributed in the full level range, the image often shows In the case of insufficient tonal contrast, the overall image appears gray and sluggish. Commonly known as a "gray tone" image. ^[7]

" ~ " Shape

Most of the ~ -shaped histograms are normal, but there are peaks in the highlight area. The shape of the entire histogram is somewhat similar to that of a crawling snail. The shape of this histogram often appears on landscape images, and the area indicated by the spikes is a whitened sky area. ^[8]

" M " shape

This is a type of histogram that puts the operator in a dilemma. As shown in the figure, the pixel level is concentrated in the highlight and dark areas of the image at the same time, but the halftone area, which should be the most detailed in the image, has little level distribution. For "M" shaped histograms, using the "Dark / Highlight" command, the image can be processed quickly with good results. ^[8]