With the development of the industry and the growth of market demand, the market demand for PC-side license plate recognition system (PC-side license plate recognition system) is becoming more and more extensive, mainly divided into: software recognition and hardware recognition. Through automatic identification and automatic comparison of license plate numbers, the system can realize automation; intelligent functions such as gate opening, automatic billing, automatic verification of user vehicle identity, automatic distinction between internal and external vehicles, automatic calculation of parking spaces, and automatic alarm.
Software recognition: The meaning of words can be understood. The license plate number is recognized by software. By installing a matching license plate recognition software on the computer, the captured pictures are recognized and processed. Its working method is to continuously capture N photos through a camera, select a clearer one, and then perform character processing through computer software to realize license plate recognition.
Because each recognition needs to capture many pictures, the speed of soft recognition is slow. In addition, the system has extremely high requirements on the captured pictures, which must be extremely clear to achieve the desired effect. The system has extremely high requirements on the on-site environment and debugging quality, and is not suitable for many occasions where the environment is not optimistic, so the placement of the equipment is extremely important.
Hardware recognition: The popular explanation is to perform character processing on the captured pictures through independent hardware devices; currently, there are two types of hardware recognition in the parking lot system industry, that is, with a separate license plate recognition device and front-end hardware recognition. Park mainly uses front-end hardware identification.
The front-end hardware recognition integrated camera meets the market demand and has been sought after by the majority of users. Yi Park front-end hardware recognition is also called an integrated license plate recognition camera. It embeds a traditional separate license plate recognition device into the camera to realize the integration of front-end hardware and camera, and perfectly realize image capture, video streaming, character recognition, and barrier lift. and so on a series of work.
Comparison of the advantages of soft recognition and hard recognition of license plate recognition on the PC side:
1. Analyze and identify patterns:
PC-side license plate recognition system: adopt video stream analysis and recognition, and conduct all-weather real-time analysis of video streams within the monitoring range;
PC-side license plate soft recognition system: image analysis and recognition, take pictures of vehicles that reach the specified range, and then analyze the photos; when the vehicle is in a bad position, the recognition is prone to errors.
2. Trigger identification method:
PC-side license plate recognition system: ground sense and video triggering are optional, no need to add detection equipment, no need to damage the ground or add engineering, 24-hour image acquisition.
PC-side license plate soft recognition system: ground sense, infrared and other peripheral vehicle detection devices are triggered; a certain amount of engineering is required.
3. Intelligent algorithm model
PC端车牌硬识别系统：采用智能模糊点阵识别算法，准确率更高，识别率大于99.70%。极少需要人工干预。
PC端车牌软识别系统：OCR/字型拓扑结构识别算法，会频繁出现误识别，准确率低于90%。需要人工不断输入纠正后过的号牌。
4、可靠性及稳定性：
PC端车牌硬识别系统：专用识别器采用TI公司的高速DSP，双CPU控制，确保了系统可靠性和稳定性。
PC端车牌软识别系统：软件识别，容易频繁出现死机等情况，需经常重新启动电脑，容易造成间断性系统瘫痪。
5、识别速度：
PC端车牌硬识别系统：整车车牌识别速度小于0.4秒，充分满足车流量大的需要;
软识别系统：整车车牌识别速度大于3秒，甚至更长，速度有些让人难以忍受。
6、车速适应性：
PC端车牌硬识别系统：车速在0-120Km/H范围内均能稳定快速识别;应用范围广泛，高速公里使用该类设备。
PC端车牌软识别系统：车速大于40Km/H时，识别率急剧下降，现被引入停车场场系统中，有待进一步完善。
7、环境适应性
PC端车牌硬识别系统：能在夜晚、阴天、雨天等各种光照条件下正常工作;
PC端车牌软识别系统：上述条件下，甚至一天的不同时间内，识别准确率起伏很大。
8、兼容能力
PC端车牌硬识别系统：无需工业IO卡的支持，借道停车场控制系统(PLC)可直接与各类IC、ID、纸票等类型停车场无缝兼容，实现车牌号与卡号必须一致才能进出的自动识别、自动打印车牌号等功能。
PC端车牌软识别系统：依赖IO卡进行车辆检测、开关道闸等动作，与停车场系统只是软件嵌入关系，硬件无联系。工程量大，用线多，稳定度差。
9、摄像机共用性
PC端车牌硬识别系统：系统可与监控系统共用摄像机，对系统无任何影响。
PC端车牌软识别系统：不可共用，否则对系统稳定性和识别率造成严重影响。
10、输出信号
PC端车牌硬识别系统：系统可输出车辆大图、号牌小图、号牌识别号码、号牌颜色和识别可信度、车流量、场内停车量等实时数据。具备车辆进出静态图片查询功能、可接驳车位引导系统等。
PC端车牌软识别系统：没有输出接口，基本为其系统自身使用，无法进行二次开发