Five Skills when Using Scanner Ⅱ

02.06.2020 0 iCODIS Official
  1. Suitable resolution

When using the scanner, many users often wonder what resolution to scan with. In fact, it depends on the actual application needs of users. Higher resolution means more image details, clearer effect and more perfect color restoring power can be obtained, but at the same time it also means that the scanned image file is enlarged and difficult to process. For the Internet with more applications, the resolution of pictures on websites is usually about 75dpi, which means that it is more than enough to scan with a resolution of 100dpi, while the resolution of pictures used for printing is usually 300 to 400dpi. Therefore, in order to print and publish works through scanning, a resolution of at least  300dpi is required, and of course, it is better to use 600dpi. If you want to print the scanned works through the printer, you must consider the resolution of the printer comprehensively. According to practical experience, a printer with a printing resolution of 1440dpi can get a good printing effect by scanning images with a resolution of 360dpi. This is because the working principle and resolution of printer and scanner are completely different.

Five Skills when Using Scanner Ⅱ

handheld book scanner

  1. Widely-used OCR

It is believed that many users purchase scanners mostly for the purpose of reducing the workload of text input and improving work efficiency. Therefore, OCR has become one of the most commonly used functions of scanners, with which it is very convenient and effective to identify Chinese characters and English on scanned documents. Therefore, besides mastering the correct scanning method, it is also extremely important to select the appropriate OCR software. At present, most commonly used OCR software is bundled with OCR document scanner. Although OCR software can automatically recognize Chinese characters, many application skills are needed to achieve high efficiency and accuracy.

First of all, the black-and-white mode should be used when scanning documents. At the same time, attention should also be paid to the Threshold value under this mode (the threshold value indicates a parameter range, and no effect can be produced if it is greater than or less than this range). This is to determine the degree of black that can be regarded as a black dot by the scanner, so that the black of text and the black of background interference can be easily distinguished. If properly adjusted, the scanning speed can be accelerated. The adjustment of this value can distinguish two or more peaks in the tone value statistical Histogram of the scanned image, and then adjust Threshold between the two to find the position with good distinguishing effect. If you think it is troublesome, there is another simple way to determine the resolution by the size of the text. Generally speaking, a resolution of 200 or 300dpi can achieve quite good effect. If the text to be scanned is smaller than that of newspapers and periodicals, the resolution can be improved, thus obtaining an enlarged scanned document and improving the recognition rate.

When users need to scan magazines with large thickness, if they scan directly, it is inevitable that some characters will not be clear and distorted due to the fact that the text cannot be completely spread out. As a result, OCR software cannot correctly recognize the characters, thus greatly reducing the recognition rate. What should I do? Users may as well split the book into single pages before scanning, and then scan them. For ordinary newspapers, the above-mentioned problems do not exist because they are in the form of single sheets. However, due to the large area of newspapers, it is not possible to scan at one time. Therefore, the scanning range is selected in advance and one area is scanned at a time during pre-scanning, thus the identification effect will be greatly improved.

  1. Transmission draft and other printed matter

In addition to scanning ordinary reflection documents, users sometimes need to scan transmission documents. Transmission draft includes slide (positive) and negative one. Since the general scanner is designed for scanning reflected documents, it is recommended to use a special film scanner with film scanning function when scanning transmitted documents.