一.引言
文字识别，也称为光学字符识别（Optical Character Recognition, OCR），是一种将不同形式的文档（如扫描的纸质文档、PDF文件或数字相机拍摄的图片）中的文字转换成可编辑和可搜索的数据的技术。随着技术的发展，文字识别技术已经成为信息管理、自动化办公和智能系统的关键组成部分。
二.简介
为了易于集成和使用，我们将文字识别OCR封装为DLL（动态链接库）。这种封装方式不仅保留了算法的性能优势，还提供了跨平台和跨语言的兼容性，目前支持编程语言如下：
- C++
- Python
- 易语言
1.C++头文件
#ifndef __SN_OCR__H__
#define __SN_OCR__H__#include "windows.h"//返回参数
typedef struct SN_STATU {int code; //错误码，如果为 0 表示成功，否则表示错误号char message[4096]; //错误信息，如果为 "OK" 表示成功，否则返回错误信息}SN_STATU;/*启动OCR文字识别服务
*
* 参数：
* [in] szOnnxFilePath： 设置 onnx 模型文件路径，如果设置为 NULL，默认和 DLL文件同级目录
* [out] pResult： 返回错误信息，参数pResult->code(错误码)如果为 0 表示成功，否则表示错误号;
*
* 返回值：成功返回0，失败返回错误号，详细错误信息请参考 pResult
*
*/
int WINAPI apiSNInitOCRServer(char* szOnnxFilePath, SN_STATU* pStatu);/*创建OCR文字识别句柄
*
* 参数：
* [in] szKey： 卡密(购买卡密：https://shop.4yuns.com/links/7C9F16B7)
* [in] pOnnxFilePath：设置 onnx 模型文件路径，如果设置为 NULL，默认和 DLL文件同级目录
* [out] pResult： 返回错误信息，参数pResult->code(错误码)如果为 0 表示成功，否则表示错误号;
*
* 返回值：成功返回句柄，失败返回NULL
*
*/
HANDLE WINAPI apiSNCreateOCRHandle(char* szKey, char* szOnnxFilePath, SN_STATU* pStatu);/*获取OCR文字识别卡密到期时间
*
* 参数：
* [in] handle： 句柄（通过调用apiSNCreateOCRHandle得到）
* [out] pResult： 返回错误信息，参数pResult->code(错误码)如果为 0 表示成功，否则表示错误号;
*
* 返回值：返回卡密到期时间，失败返回NULL，错误信息请查看参数 pResult->message
*
*/
char* WINAPI apiSNGetKeyExpiresTime(HANDLE handle, SN_STATU* pResult);/*获取OCR文字识别结果（以json字符串形式返回）
*
* 参数：
* [in] handle： 句柄（通过调用apiSNCreateOCRHandle得到）
* [in] szImageFilePath： 图片路径
* [out] pResult： 返回错误信息，参数pResult->code(错误码)如果为 0 表示成功，否则表示错误号;
*
* 返回值：返回OCR文字识别结果（以json字符串形式返回），失败返回NULL，错误信息请查看参数 pResult->message
*
*/
char* WINAPI apiSNGetOCRFromImage(HANDLE handle, char* szImageFilePath, SN_STATU* pStatu);/*释放OCR文字识别句柄（释放内存）
*
* 参数：
* [in] handle： 句柄（通过调用apiSNCreateOCRHandle得到）
*
* 返回值：返回 0 表示成功，其他值表示错误号;
*
*/
int WINAPI apiSNDestroyOCRHandle(HANDLE handle);#endif2.Python调用dll接口
from ctypes import cdll, c_char_p, Structure, byref
import ctypes# 定义SN_STATU结构体
class SN_STATU(Structure):_fields_ = [("code", ctypes.c_int),("message", c_char_p * 4096)]# 加载DLL
lib = cdll.LoadLibrary('D://SNOCR.dll')# 设置函数参数类型
lib.apiSNInitOCRServer.argtypes = [c_char_p, ctypes.POINTER(SN_STATU)]
lib.apiSNInitOCRServer.restype = ctypes.c_intlib.apiSNCreateOCRHandle.argtypes = [c_char_p, c_char_p, ctypes.POINTER(SN_STATU)]
lib.apiSNCreateOCRHandle.restype = ctypes.c_void_plib.apiSNGetKeyExpiresTime.argtypes = [ctypes.c_void_p, ctypes.POINTER(SN_STATU)]
lib.apiSNGetKeyExpiresTime.restype = c_char_plib.apiSNGetOCRFromImage.argtypes = [ctypes.c_void_p, c_char_p, ctypes.POINTER(SN_STATU)]
lib.apiSNGetOCRFromImage.restype = c_char_plib.apiSNDestroyOCRHandle.argtypes = [ctypes.c_void_p]
lib.apiSNDestroyOCRHandle.restype = ctypes.c_int# 初始化变量
statu = SN_STATU()
key = b"SNKJe9xffLhdFY7r3TcffXq44ThDVcE3BQFQFfVA9VG4"
onnx_path = b"D://SNOCR.onnx"
image_path = b"D://7.jpg"# 1. 启动OCR服务
ret = lib.apiSNInitOCRServer(onnx_path, byref(statu))
if ret < 0:print(f"Error:{statu.message.decode('utf-8')}")exit()# 2. 创建OCR句柄
handle = lib.apiSNCreateOCRHandle(key, onnx_path, byref(statu))
if not handle:print(f"Error:{statu.message.decode('utf-8')}")exit()# 3. 获取卡密到期时间
expires_time = lib.apiSNGetKeyExpiresTime(handle, byref(statu))
if not expires_time:print(f"Error:{statu.message.decode('utf-8')}")exit()
print(f"Expires Time: {expires_time.decode('utf-8')}")# 4. 识别OCR，返回Json字符串
ocr_result = lib.apiSNGetOCRFromImage(handle, image_path, byref(statu))
if not ocr_result:print(f"Error:{statu.message.decode('utf-8')}")exit()
try:print(f"OCR Result: {ocr_result.decode('utf-8')}")
except UnicodeDecodeError:print(f"OCR Result: {ocr_result.decode('GBK')}")# 5. 释放内存
lib.apiSNDestroyOCRHandle(handle)# 等待输入，防止程序直接退出
input("Press Enter to exit...")三.效果演示
1.图片1
识别效果：
{"type": 0,"task_id": 1,"err_code": 0,"ocr_result": {"single_result": [{"left": 24.700000,"top": 17.333332,"right": 326.299957,"bottom": 32.499992,"str_utf8": "在易语言中，如何为按钮添加点击事件处理代码?","rate": "0.995533"}, {"left": 23.806435,"top": 63.233559,"right": 324.158508,"bottom": 79.905136,"str_utf8": "我想在GUI中添加一个文本框，我应该如何操作?","rate": "0.967164"}, {"left": 25.554037,"top": 110.492912,"right": 354.041595,"bottom": 124.103584,"str_utf8": "易语言中有哪些控件是常用的，它们各自有什么特点?","rate": "0.996690"}],"width": "416","height": "152"}
}2.图片2
识别效果：
{"type": 0,"task_id": 1,"err_code": 0,"ocr_result": {"single_result": [{"left": 323.454163,"top": 14.279167,"right": 389.262512,"bottom": 37.870834,"str_utf8": "国热点","rate": "0.745956"}, {"left": 17.981834,"top": 57.859264,"right": 258.913910,"bottom": 75.778633,"str_utf8": "Python即将成为年度语言，TIOB","rate": "0.961854"}, {"left": 18.625000,"top": 86.916664,"right": 227.845840,"bottom": 100.575000,"str_utf8": "12月TIOBE编程语言榜单已发布","rate": "0.956302"}, {"left": 18.004168,"top": 130.995834,"right": 262.612488,"bottom": 147.758331,"str_utf8": "传Win11硬件门槛大降，老旧PC","rate": "0.990127"}, {"left": 17.383333,"top": 158.933334,"right": 256.404175,"bottom": 173.212494,"str_utf8": "TPM20是未来Windows不可或缺的","rate": "0.993834"}, {"left": 17.976627,"top": 203.605774,"right": 259.543152,"bottom": 221.703751,"str_utf8": "OpenAlSora上线即炸服、1条视","rate": "0.979807"}, {"left": 17.362951,"top": 231.025940,"right": 256.424805,"bottom": 246.494904,"str_utf8": "作为一款旨在理解和模拟现实的AI基","rate": "0.929840"}, {"left": 19.866667,"top": 276.891663,"right": 247.712463,"bottom": 293.654175,"str_utf8": "彻底放弃React!频繁更新和管","rate": "0.984215"}, {"left": 17.383333,"top": 304.829163,"right": 261.991669,"bottom": 319.108337,"str_utf8": "React 真的已经不再适合现代开发了吗?","rate": "0.973967"}, {"left": 18.591219,"top": 349.496246,"right": 256.436981,"bottom": 367.271393,"str_utf8": "告别VMware!被博通收购后涨价","rate": "0.997881"}, {"left": 17.949070,"top": 376.545624,"right": 266.386017,"bottom": 392.872589,"str_utf8": "面对VMware增长十倍的收费，近日英","rate": "0.990023"}, {"left": 322.172638,"top": 56.995289,"right": 555.074097,"bottom": 75.172531,"str_utf8": "TOP专家加盟OpenCloudOS年会","rate": "0.971594"}, {"left": 322.833344,"top": 86.295837,"right": 412.854156,"bottom": 99.954170,"str_utf8": "睹重磅阵容!","rate": "0.936653"}, {"left": 322.803558,"top": 130.880295,"right": 564.365479,"bottom": 147.844025,"str_utf8": "亿级订单系统的数据库查询性能优","rate": "0.995852"}, {"left": 321.567688,"top": 157.681427,"right": 560.010559,"bottom": 173.852203,"str_utf8": "为什么没考虑Donis?因为ES是团队应","rate": "0.967674"}, {"left": 321.591675,"top": 204.254166,"right": 469.970825,"bottom": 221.016663,"str_utf8": "ChatGPT崩了上热搜","rate": "0.984410"}, {"left": 322.833252,"top": 232.191650,"right": 485.491608,"bottom": 246.470810,"str_utf8": "Gemini20发布|极客头条","rate": "0.958749"}, {"left": 320.350000,"top": 276.270844,"right": 564.337524,"bottom": 294.275000,"str_utf8": "2024OpenCloudOS年会即将启航","rate": "0.951624"}, {"left": 320.970825,"top": 304.829163,"right": 435.204163,"bottom": 319.108337,"str_utf8": "前瞻亮点独家揭秘","rate": "0.956549"}, {"left": 322.212494,"top": 350.150000,"right": 520.879150,"bottom": 366.912506,"str_utf8": "降价+豪礼!双十二福利来了","rate": "0.984479"}, {"left": 320.970825,"top": 376.845825,"right": 518.395813,"bottom": 392.366669,"str_utf8": "最值得抢购的C++系列精品课程","rate": "0.965407"}],"width": "596","height": "417"}
}四.常见问题
1.是否支持多线程
支持
五.更新日志
- 2024.12.15 OCR 文字识别支持C++/Python/易语言
六.云盘源码下载
- 百度云盘
- 夸克云盘
- 123云盘
