1. OCR is not 100% accurate all the time.
2. The most important thing for business card scanning apps is the quality of initial image. The background, the font size, the font color, the clearness of objects and other aspects all affect the quality of the image taken by your camera(or phone camera) and will affect the recognition results finally.
3. 300 DPI is the standard quality for image to scan. Why? 300 DPI is just that number where you gain the most accuracy without sacrificing speed and file size according to analysis. Because the improvement gap between 200 DPI scan and 300 DPI scan will be at least 2 times the improvement gap of any other resolutions. However, the improvement gap of 300 DPI and 400 DPI is nearly absent.
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