使用FreeType2绘制字体并描边

app/src/main/cpp/PhoneDevice.cpp

@@ -928,45 +928,23 @@ void visualize(const char* filename, const ncnn::Mat& m)
     cv::imwrite(filename, a);
 }
 
-void DrawOutlineText(cv::Mat& mat, const std::string& str, cv::Point startPoint, double fontScale, cv::Scalar clr1, cv::Scalar clr2, int thickness1, int thickness2)
+void DrawOutlineText(cv::Ptr<cv::ft::FreeType2> ft2, cv::Mat& mat, const std::string& str, cv::Point startPoint, int fontSize, cv::Scalar clr, int thickness)
 {
-    std::vector<std::string> chars;
-    splitUtf8Str(str, chars);
+    std::vector<std::string> lines = split(str, "\n");
     int lineHeight = 0;
     cv::Point pt = startPoint;
-    cv::Size textSize, textSize2;
+    cv::Size textSize;
     int baseline = 0;
-    cv::Point pt2;
-
-    for (std::vector<std::string>::const_iterator it = chars.cbegin(); it != chars.cend(); ++it )
-    {
-        if (it->compare("\n") == 0)
-        {
-            pt.x = startPoint.x;
-            pt.y += lineHeight > 0 ? (lineHeight + 2) : 0;
-            continue;
-        }
-
-        textSize = cv::getTextSize(*it, cv::FONT_HERSHEY_COMPLEX, fontScale, thickness1, &baseline);
-        textSize2 = cv::getTextSize(*it, cv::FONT_HERSHEY_COMPLEX, fontScale, thickness2, &baseline);
 
-        lineHeight = std::max(lineHeight, std::max(textSize.height, textSize2.height));
-
-        if (it->compare(" ") != 0)
+    for (std::vector<std::string>::const_iterator it = lines.cbegin(); it != lines.cend(); ++it )
     {
-            // cv2.putText(image,"text",(180,150),cv2.FONT_HERSHEY_COMPLEX,3,(255,255,255),16,cv2.LINE_AA)
-            // cv2.putText(image,"text",(180,150),cv2.FONT_HERSHEY_COMPLEX,3,(0,0,0),4,cv2.LINE
-
-            // balck
+        textSize = ft2->getTextSize(*it, fontSize, thickness, &baseline);
+        lineHeight = std::max(lineHeight, textSize.height);
 
-            cv::putText(mat, *it, pt, cv::FONT_HERSHEY_COMPLEX, fontScale, clr1, thickness1, cv::LINE_AA);
-            // white
-            pt2 = pt;
-            // pt2.y += 1;
-            cv::putText(mat, *it, pt2, cv::FONT_HERSHEY_COMPLEX, fontScale, clr2, thickness2, cv::LINE_AA);
-        }
+        ft2->putText(mat, *it, pt, fontSize, clr, thickness, cv::LINE_AA, false);
 
-        pt.x += std::max(textSize.width, textSize2.width);
+        pt.x = startPoint.x;
+        pt.y += lineHeight > 0 ? (lineHeight + 2) : 0;
     }
 }
 
@@ -1045,17 +1023,20 @@ bool CPhoneDevice::OnImageReady(cv::Mat& mat)
         }
     }
 
-    int thickness2 = 4 * ratio;
-    if (thickness2 < 2) thickness2 = 2;
-    int thickness1 = 2 * ratio;
-    if (thickness1 < 1) thickness1 = 1;
+    int thickness = 4 * ratio;
+    if (thickness < 2) thickness = 2;
 
-    cv::Scalar scalar1(0, 0, 0);    // black
-    cv::Scalar scalar2(255, 255, 255);  // white
+    cv::Scalar scalar(255, 255, 255);  // white
+
+    int fontSize = 24;
+    std::string fontPath = m_appPath+ "fonts/Noto.ttf";
+    cv::Ptr<cv::ft::FreeType2> ft2;
+    ft2 = cv::ft::createFreeType2();
+    ft2->loadFontData(fontPath.c_str(), 0);
 
 #ifdef _DEBUG
 
-    cv::Scalar scalar(0, 0, 255);  // red
+    cv::Scalar scalarRed(0, 0, 255);  // red
 
     NdkCamera::CAPTURE_RESULT captureResult = mCamera->getCaptureResult();
     char str[128] = { 0 };
@@ -1068,13 +1049,9 @@ bool CPhoneDevice::OnImageReady(cv::Mat& mat)
              captureResult.hdrMode);
     // cv::putText(mat, str, cv::Point(0, mat.rows - 20), cv::FONT_HERSHEY_COMPLEX, fontScale, scalar, thickness1, cv::LINE_AA);
 
-    std::string fontPath = m_appPath+ "fonts/Noto.ttf";
-    cv::Ptr<cv::ft::FreeType2> ft2;
-    ft2 = cv::ft::createFreeType2();
-    ft2->loadFontData(fontPath.c_str(), 0);
 
     ft2->putText(mat, str, cv::Point(0, mat.rows - 48),
-                 36, scalar, thickness1, cv::LINE_AA, false);
+                 fontSize, scalarRed, thickness, cv::LINE_AA, false);
 
     // text.putText(mat, str.c_str(), cv::Point(0, mat.rows - 20), scalar);
 
@@ -1093,8 +1070,7 @@ bool CPhoneDevice::OnImageReady(cv::Mat& mat)
             continue;
         }
 
-        textSize = cv::getTextSize(it->text, cv::FONT_HERSHEY_TRIPLEX, fontScale, thickness1, &baseline);
-        textSize2 = cv::getTextSize(it->text, cv::FONT_HERSHEY_TRIPLEX, fontScale, thickness2, &baseline);
+        textSize = ft2->getTextSize(it->text, fontSize, thickness, &baseline);
 
         if (it->alignment == OSD_ALIGNMENT_TOP_LEFT)
         {
@@ -1125,7 +1101,7 @@ bool CPhoneDevice::OnImageReady(cv::Mat& mat)
         pt2 = pt1;
         pt2.y +=  textSize.height;
 
-        DrawOutlineText(mat, it->text, pt1, fontScale, scalar1, scalar2, thickness1, thickness2);
+        DrawOutlineText(ft2, mat, it->text, pt1, fontScale, scalar, thickness);
     }
 
     vector <int> params;