Detailed Explanation of Scanner Resolution--Common Terms (3)

6. Image Resolution

Image resolution refers to the total amount of information represented by the number of pixels in a digital image, such as 40002600 (Pixel). Regardless of the medium used, image resolution is important when determining if an image contains the amount of information required for high-quality output. A high-resolution image contains more pixels than a low-resolution image of the same print size, and therefore has a smaller pixel point. For example, a 1 inch X1 inch image with a 72 dpi resolution contains a total of 5,184 pixels; an image with the same 1 inch X1 inch and a resolution of 300 dpi contains a total of 90,000 pixels.

Because higher resolution images use more pixels to represent each unit area, they typically reproduce finer color transitions when printed than lower resolution images. However, for images scanned or created at lower resolutions, increasing the resolution can only extend the original pixel information to a larger number of pixels without increasing the image quality.

To determine the resolution of the image to use, consider the medium from which the image was ultimately released. If the image is created for web page display, the image resolution only needs to meet the typical display resolution (72 dpi or 96 dpi). However, if used for printouts, using a resolution that is too low can result in poor sharpness and coarse display. Using too high a resolution (smaller than the output device can produce pixels) can increase image files and reduce image printing speed.

With so many types of resolution, you may wonder which type is the most important and which one needs control. It can be said that in order to ensure the quality of the image from input to output from beginning to end, if you plan to output images to slides, multimedia video equipment, etc., then only two types of resolution need to be coordinated, namely the input resolution and the display resolution; if To output to a printer (or print), you need to control four types of resolution.

Input resolution - ensure that there is enough information to enter the digitized image to meet the final requirements.

Image resolution - In order to get a good output, you should verify that the image contains no more or less information.

Output resolution - should ensure that the information density can meet the requirements of the network density or printer resolution.

Printer resolution - The highest resolution of the printer should be known.

(to be continued)