This depends on the resolution and complexity of the barcode you are scanning. Generally speaking, not counting the difference can reach 6 megapixels can scan the two-dimensional code, counting the difference at least 12 megapixels, scanning barcode can be appropriate to reduce the pixel, after all, the bar code is much simpler than two-dimensional.
The code scanner is a machine that reads barcode information. The use of infrared light source is emitted, and then based on the results of the reflection, the chip is used to decode the code, and then finally return the correct characters represented by the bar code.
The principle of code scanner is as follows:
The barcode is made up of a combination of black and white lines, and the barcode scanner is to judge the width of the barcode with the help of the difference in the degree of infrared reflection between black and white. Barcode scanners contain sensors that generate different voltages depending on the intensity of the reflected light, which in turn generates logical data.
The logic signals received by the barcode scanner can be used to generate digital data according to coding rules.