【bug修复】（黄根）解决二维码识别潜在崩溃问题

【工作量】2h
【评审人】叶长城

app/src/main/cpp/paperPreIdentify.cpp

@@ -106,8 +106,8 @@ void findQrcode(string & strPath, string & strRet)
     vector<shared_future<string>> tFutures;
     shared_future<string> tFut1 = std::async(launch::async, getQrcode, tImg, 0, 0);
     shared_future<string> tFut2 = std::async(launch::async, getQrcode, tImg, tImg.cols * 3 / 4, 0);
-    shared_future<string> tFut3 = std::async(launch::async, getQrcode, tImg, tImg.cols * 3 / 4, tImg.rows * 4 / 5);
-    shared_future<string> tFut4 = std::async(launch::async, getQrcode, tImg, 0, tImg.rows * 4 / 5);
+    shared_future<string> tFut3 = std::async(launch::async, getQrcode, tImg, tImg.cols * 3 / 4, tImg.rows * 3 / 4);
+    shared_future<string> tFut4 = std::async(launch::async, getQrcode, tImg, 0, tImg.rows * 3 / 4);
     tFutures.emplace_back(tFut1);
     tFutures.emplace_back(tFut2);
     tFutures.emplace_back(tFut3);