fix image path (#5714)

* fix PP-TinyPose PrepareKeypointDataSet document test=document_fix

* fix PP-TinyPose/introduction_en.ipynb

* fix PP-TinyPose PP-Vehicle PP-HumanV2 introduction image path

modelcenter/PP-HumanV2/introduction_cn.ipynb

@@ -270,7 +270,7 @@
     "PP-Human 整体方案如下图所示:\n",
     "\n",
     "<div width=\"1000\" align=\"center\">\n",
-    "  <img src=\"pphumanv2.png\"/>\n",
+    "  <img src=\"https://github.com/PaddlePaddle/PaddleDetection/raw/develop/docs/images/pphumanv2.png\"/>\n",
     "</div>\n",
     "\n",
     "### 行人检测\n",

modelcenter/PP-HumanV2/introduction_en.ipynb

@@ -247,7 +247,7 @@
     "The overall solution for PP-Human is shown in the graph below:\n",
     "\n",
     "<div width=\"1000\" align=\"center\">\n",
-    "  <img src=\"pphumanv2.png\"/>\n",
+    "  <img src=\"https://github.com/PaddlePaddle/PaddleDetection/raw/develop/docs/images/pphumanv2.png\"/>\n",
     "</div>\n",
     "\n",
     "### Pedestrian detection\n",

modelcenter/PP-TinyPose/introduction_cn.ipynb

@@ -245,7 +245,7 @@
    "source": [
     "## 4. 方案介绍\n",
     "<div align=\"center\">\n",
-    "  <img src=\"tinypose_pipeline.png\" width='800'/>\n",
+    "  <img src=\"https://github.com/PaddlePaddle/PaddleDetection/raw/develop/docs/images/tinypose_pipeline.png\" width='800'/>\n",
     "</div>"
    ]
   }

modelcenter/PP-TinyPose/introduction_en.ipynb

@@ -231,7 +231,7 @@
    "source": [
     "## 4. Solution\n",
     "<div align=\"center\">\n",
-    "  <img src=\"tinypose_pipeline.png\" width='800'/>\n",
+    "  <img src=\"https://github.com/PaddlePaddle/PaddleDetection/raw/develop/docs/images/tinypose_pipeline.png\" width='800'/>\n",
     "</div>"
    ]
   }

modelcenter/PP-Vehicle/introduction_cn.ipynb

@@ -259,7 +259,7 @@
     "PP-Vehicle 整体方案如下图所示:\n",
     "\n",
     "<div width=\"1000\" align=\"center\">\n",
-    "  <img src=\"ppvehicle.png\"/>\n",
+    "  <img src=\"https://github.com/PaddlePaddle/PaddleDetection/raw/develop/docs/images/ppvehicle.png\"/>\n",
     "</div>\n",
     "\n",
     "\n",

modelcenter/PP-Vehicle/introduction_en.ipynb

@@ -232,7 +232,7 @@
     "The overall solution for PP-Vehicle is shown in the graph below:\n",
     "\n",
     "<div width=\"1000\" align=\"center\">\n",
-    "  <img src=\"ppvehicle.png\"/>\n",
+    "  <img src=\"https://github.com/PaddlePaddle/PaddleDetection/raw/develop/docs/images/ppvehicle.png\"/>\n",
     "</div>\n",
     "\n",
     "\n",