The dpi information is abnormal. What does it mean to save the picture?

DPI stands for resolution, which refers to the number of dots per inch of length.

Abnormal dpi information means there is a problem with the resolution. The current format for saving the image cannot be saved or cannot be printed. In this case, the format for saving the image needs to be changed or the format for saving the image must be rewritten. (Recommended learning: web front-end video tutorial)

DPI can be subdivided into horizontal resolution and vertical resolution. For example, if a 1 inch by 1 inch picture has a horizontal resolution of 100 dpi and a vertical resolution of 50 dpi, then it means: it is divided into 100 small segments per inch horizontally and 50 small segments per inch vertically, just like on a meter stick Every grid is like that.

DPI (Dots Per Inch) is a unit of measurement for dot matrix digital images, which refers to the number of sampled, displayable or output dots per inch of length.

DPI is a unit of measurement for the resolution of devices such as printers and mice. It is one of the main parameters to measure the printing accuracy of the printer. Generally speaking, the higher the DPI value, the higher the printing accuracy of the printer.

DPI refers to pixels per inch, which is the scanning accuracy. The lower the DPI, the lower the resolution of the scan. Due to the influence of network transmission speed, the pictures used on the web are all 72dpi. However, this parameter cannot be used for developing photos. It must be 300dpi or higher 350dpi. For example, if you want to develop a 4*6-inch photo, the scanning accuracy must be 300dpi, then the file size should be (4*300)*(6*300)=1200 pixels*1800 pixels.

DPI is originally a unit of measurement in printing, which means the number of dots that can be printed per inch (Dot Per Inch).

However, with the rapid development of digital input and output devices, most people also express the resolution of digital images in DPI, but more rigorous people may notice that the dots (Dot) and dots calculated during printing The display pixels of computer monitors are not the same, so more professional people will use PPI (Pixel Per Inch) to express the resolution of digital images to distinguish between the two.

We usually talk about the DPI of the printer resolution, which refers to the "theoretical number of ink dots" that can be printed per inch under the highest resolution mode of the printer.

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