Method and device for acquiring digital image data

Abstract

The invention discloses a method and a device for acquiring digital image data. In the above method, after sending the Mth line synchronization signal to an image sensor, an ultraviolet light source is turned on, wherein the ultraviolet light source is used to illuminate the bills to be scanned to Make the image sensor collect the ultraviolet light image of the bill to be scanned, M is a positive integer; when sending the M+Nth line synchronization signal to the image sensor, start the first timing, and when the first timing reaches the first preset time length, turn off an ultraviolet light source, wherein N is a positive integer, and the first preset duration is greater than the pulse width of the M+Nth line synchronization signal, and less than the working period of the M+Nth line synchronization signal; The ultraviolet light digital image data corresponding to the duty cycle of the synchronization signal. According to the technical solution provided by the present invention, the fluorescent fiber filaments contained therein can be clearly displayed in the digital image, and the brightness of the background part other than the fluorescent fiber filaments in the digital image is not affected.

Description

technical field [0001] The present invention relates to the field of image processing, in particular to a method and device for acquiring digital image data. Background technique [0002] Financial bills are bills issued by financial institutions or financial institutions undertake payment obligations. The existing financial bills in my country include: bills of exchange, checks, promissory notes, etc. At present, the anti-counterfeiting method of financial bills (hereinafter referred to as bills) mainly collects the images of bills through financial bill image reading equipment (hereinafter referred to as bill image reading devices), and compares the images of the bills at the time of payment with the images of the bills at the time of issuance. To judge the authenticity of bills. In recent years, some special bills have enhanced the anti-counterfeiting characteristics of bills by embedding irregular fluorescent fiber filaments in the bill paper. The fluorescent fiber fil...

AI Technical Summary

Problems solved by technology

When the image reading device is used to acquire the image of the bill, if the luminous device emits light for a short time each time, the fluorescent fiber filament cannot fluoresce or the brightness of the fluoresced light is weak due to the insufficient energy of the emitted ultraviolet light, resulting in It is difficult to extract the fluorescent fiber features of the bill from the bill image obtained by the image reading device; and if the light-emitting time of the light emitter is prolonged, the reading cycle of the image reading device needs to be adjusted synchronously. At this time, due to the longer reading cycle The accumulation of energy obtained by the photosensitive array makes the background part of the acquired bill image except for the fluorescent fiber filaments brighter, that is, the contrast of the bill image captured by the image reading device is reduced, making it difficult to extract the characteristics of the fluorescent fiber filaments of the bill

[0005] Aiming at the problem that the image reading method in the related art is difficult to extract the fluorescent fiber features of the bill through the acquired bill image, no effective solution has been proposed so far

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