Add hooks for image processing to examples (#27)

Fixes #23.

.gitignore

@@ -16,5 +16,3 @@ deps/tools/setuidgids
 *.sw?
 *.debug
 stage2/01-sys-tweaks/extfiles
-deps/examples/cpp-multiCameraServer/main.cpp
-deps/examples/java-multiCameraServer/src

deps/04-copy.sh

@@ -7,9 +7,6 @@ mkdir -p ${DEST}
 #
 # examples
 #
-mkdir -p examples/java-multiCameraServer/src/main/java
-cp allwpilib/cameraserver/multiCameraServer/src/main/java/Main.java examples/java-multiCameraServer/src/main/java/
-cp allwpilib/cameraserver/multiCameraServer/src/main/native/cpp/main.cpp examples/cpp-multiCameraServer/
 
 sh -c 'cd examples && zip -r - java-multiCameraServer' > ${DEST}/java-multiCameraServer.zip
 sh -c 'cd examples && zip -r - cpp-multiCameraServer' > ${DEST}/cpp-multiCameraServer.zip

deps/examples/cpp-multiCameraServer/main.cpp

@@ -0,0 +1,224 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2018 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include <cstdio>
+#include <string>
+#include <thread>
+#include <vector>
+
+#include <networktables/NetworkTableInstance.h>
+#include <vision/VisionPipeline.h>
+#include <vision/VisionRunner.h>
+#include <wpi/StringRef.h>
+#include <wpi/json.h>
+#include <wpi/raw_istream.h>
+#include <wpi/raw_ostream.h>
+
+#include "cameraserver/CameraServer.h"
+
+/*
+   JSON format:
+   {
+       "team": <team number>,
+       "ntmode": <"client" or "server", "client" if unspecified>
+       "cameras": [
+           {
+               "name": <camera name>
+               "path": <path, e.g. "/dev/video0">
+               "pixel format": <"MJPEG", "YUYV", etc>   // optional
+               "width": <video mode width>              // optional
+               "height": <video mode height>            // optional
+               "fps": <video mode fps>                  // optional
+               "brightness": <percentage brightness>    // optional
+               "white balance": <"auto", "hold", value> // optional
+               "exposure": <"auto", "hold", value>      // optional
+               "properties": [                          // optional
+                   {
+                       "name": <property name>
+                       "value": <property value>
+                   }
+               ]
+           }
+       ]
+   }
+ */
+
+#ifdef __RASPBIAN__
+static const char* configFile = "/boot/frc.json";
+#else
+static const char* configFile = "frc.json";
+#endif
+
+namespace {
+
+unsigned int team;
+bool server = false;
+
+struct CameraConfig {
+  std::string name;
+  std::string path;
+  wpi::json config;
+};
+
+std::vector<CameraConfig> cameraConfigs;
+
+wpi::raw_ostream& ParseError() {
+  return wpi::errs() << "config error in '" << configFile << "': ";
+}
+
+bool ReadCameraConfig(const wpi::json& config) {
+  CameraConfig c;
+
+  // name
+  try {
+    c.name = config.at("name").get<std::string>();
+  } catch (const wpi::json::exception& e) {
+    ParseError() << "could not read camera name: " << e.what() << '\n';
+    return false;
+  }
+
+  // path
+  try {
+    c.path = config.at("path").get<std::string>();
+  } catch (const wpi::json::exception& e) {
+    ParseError() << "camera '" << c.name
+                 << "': could not read path: " << e.what() << '\n';
+    return false;
+  }
+
+  c.config = config;
+
+  cameraConfigs.emplace_back(std::move(c));
+  return true;
+}
+
+bool ReadConfig() {
+  // open config file
+  std::error_code ec;
+  wpi::raw_fd_istream is(configFile, ec);
+  if (ec) {
+    wpi::errs() << "could not open '" << configFile << "': " << ec.message()
+                << '\n';
+    return false;
+  }
+
+  // parse file
+  wpi::json j;
+  try {
+    j = wpi::json::parse(is);
+  } catch (const wpi::json::parse_error& e) {
+    ParseError() << "byte " << e.byte << ": " << e.what() << '\n';
+    return false;
+  }
+
+  // top level must be an object
+  if (!j.is_object()) {
+    ParseError() << "must be JSON object\n";
+    return false;
+  }
+
+  // team number
+  try {
+    team = j.at("team").get<unsigned int>();
+  } catch (const wpi::json::exception& e) {
+    ParseError() << "could not read team number: " << e.what() << '\n';
+    return false;
+  }
+
+  // ntmode (optional)
+  if (j.count("ntmode") != 0) {
+    try {
+      auto str = j.at("ntmode").get<std::string>();
+      wpi::StringRef s(str);
+      if (s.equals_lower("client")) {
+        server = false;
+      } else if (s.equals_lower("server")) {
+        server = true;
+      } else {
+        ParseError() << "could not understand ntmode value '" << str << "'\n";
+      }
+    } catch (const wpi::json::exception& e) {
+      ParseError() << "could not read ntmode: " << e.what() << '\n';
+    }
+  }
+
+  // cameras
+  try {
+    for (auto&& camera : j.at("cameras")) {
+      if (!ReadCameraConfig(camera)) return false;
+    }
+  } catch (const wpi::json::exception& e) {
+    ParseError() << "could not read cameras: " << e.what() << '\n';
+    return false;
+  }
+
+  return true;
+}
+
+cs::UsbCamera StartCamera(const CameraConfig& config) {
+  wpi::outs() << "Starting camera '" << config.name << "' on " << config.path
+              << '\n';
+  auto camera = frc::CameraServer::GetInstance()->StartAutomaticCapture(
+      config.name, config.path);
+
+  camera.SetConfigJson(config.config);
+
+  return camera;
+}
+
+// example pipeline
+class MyPipeline : public frc::VisionPipeline {
+ public:
+  int val = 0;
+
+  void Process(cv::Mat& mat) override {
+    ++val;
+  }
+};
+}  // namespace
+
+int main(int argc, char* argv[]) {
+  if (argc >= 2) configFile = argv[1];
+
+  // read configuration
+  if (!ReadConfig()) return EXIT_FAILURE;
+
+  // start NetworkTables
+  auto ntinst = nt::NetworkTableInstance::GetDefault();
+  if (server) {
+    wpi::outs() << "Setting up NetworkTables server\n";
+    ntinst.StartServer();
+  } else {
+    wpi::outs() << "Setting up NetworkTables client for team " << team << '\n';
+    ntinst.StartClientTeam(team);
+  }
+
+  // start cameras
+  std::vector<cs::VideoSource> cameras;
+  for (auto&& cameraConfig : cameraConfigs)
+    cameras.emplace_back(StartCamera(cameraConfig));
+
+  // start image processing on camera 0 if present
+  if (cameras.size() >= 1) {
+    std::thread([&] {
+      frc::VisionRunner<MyPipeline> runner(cameras[0], new MyPipeline(),
+                                           [&](MyPipeline &pipeline) {
+        // do something with pipeline results
+      });
+      /* something like this for GRIP:
+      frc::VisionRunner<MyPipeline> runner(cameras[0], new grip::GripPipeline(),
+                                           [&](grip::GripPipeline& pipeline) {
+        ...
+      });
+       */
+      runner.RunForever();
+    });
+  }
+
+  // loop forever
+  for (;;) std::this_thread::sleep_for(std::chrono::seconds(10));
+}

deps/examples/java-multiCameraServer/src/main/java/Main.java

@@ -0,0 +1,245 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2018 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.List;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+
+import edu.wpi.cscore.VideoSource;
+import edu.wpi.first.cameraserver.CameraServer;
+import edu.wpi.first.networktables.NetworkTableInstance;
+import edu.wpi.first.vision.VisionPipeline;
+import edu.wpi.first.vision.VisionThread;
+
+import org.opencv.core.Mat;
+
+/*
+   JSON format:
+   {
+       "team": <team number>,
+       "ntmode": <"client" or "server", "client" if unspecified>
+       "cameras": [
+           {
+               "name": <camera name>
+               "path": <path, e.g. "/dev/video0">
+               "pixel format": <"MJPEG", "YUYV", etc>   // optional
+               "width": <video mode width>              // optional
+               "height": <video mode height>            // optional
+               "fps": <video mode fps>                  // optional
+               "brightness": <percentage brightness>    // optional
+               "white balance": <"auto", "hold", value> // optional
+               "exposure": <"auto", "hold", value>      // optional
+               "properties": [                          // optional
+                   {
+                       "name": <property name>
+                       "value": <property value>
+                   }
+               ]
+           }
+       ]
+   }
+ */
+
+public final class Main {
+  private static String configFile = "/boot/frc.json";
+
+  @SuppressWarnings("MemberName")
+  public static class CameraConfig {
+    public String name;
+    public String path;
+    public JsonObject config;
+  }
+
+  public static int team;
+  public static boolean server;
+  public static List<CameraConfig> cameraConfigs = new ArrayList<>();
+
+  private Main() {
+  }
+
+  /**
+   * Report parse error.
+   */
+  public static void parseError(String str) {
+    System.err.println("config error in '" + configFile + "': " + str);
+  }
+
+  /**
+   * Read single camera configuration.
+   */
+  public static boolean readCameraConfig(JsonObject config) {
+    CameraConfig cam = new CameraConfig();
+
+    // name
+    JsonElement nameElement = config.get("name");
+    if (nameElement == null) {
+      parseError("could not read camera name");
+      return false;
+    }
+    cam.name = nameElement.getAsString();
+
+    // path
+    JsonElement pathElement = config.get("path");
+    if (pathElement == null) {
+      parseError("camera '" + cam.name + "': could not read path");
+      return false;
+    }
+    cam.path = pathElement.getAsString();
+
+    cam.config = config;
+
+    cameraConfigs.add(cam);
+    return true;
+  }
+
+  /**
+   * Read configuration file.
+   */
+  @SuppressWarnings("PMD.CyclomaticComplexity")
+  public static boolean readConfig() {
+    // parse file
+    JsonElement top;
+    try {
+      top = new JsonParser().parse(Files.newBufferedReader(Paths.get(configFile)));
+    } catch (IOException ex) {
+      System.err.println("could not open '" + configFile + "': " + ex);
+      return false;
+    }
+
+    // top level must be an object
+    if (!top.isJsonObject()) {
+      parseError("must be JSON object");
+      return false;
+    }
+    JsonObject obj = top.getAsJsonObject();
+
+    // team number
+    JsonElement teamElement = obj.get("team");
+    if (teamElement == null) {
+      parseError("could not read team number");
+      return false;
+    }
+    team = teamElement.getAsInt();
+
+    // ntmode (optional)
+    if (obj.has("ntmode")) {
+      String str = obj.get("ntmode").getAsString();
+      if ("client".equalsIgnoreCase(str)) {
+        server = false;
+      } else if ("server".equalsIgnoreCase(str)) {
+        server = true;
+      } else {
+        parseError("could not understand ntmode value '" + str + "'");
+      }
+    }
+
+    // cameras
+    JsonElement camerasElement = obj.get("cameras");
+    if (camerasElement == null) {
+      parseError("could not read cameras");
+      return false;
+    }
+    JsonArray cameras = camerasElement.getAsJsonArray();
+    for (JsonElement camera : cameras) {
+      if (!readCameraConfig(camera.getAsJsonObject())) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  /**
+   * Start running the camera.
+   */
+  public static VideoSource startCamera(CameraConfig config) {
+    System.out.println("Starting camera '" + config.name + "' on " + config.path);
+    VideoSource camera = CameraServer.getInstance().startAutomaticCapture(
+        config.name, config.path);
+
+    Gson gson = new GsonBuilder().create();
+
+    camera.setConfigJson(gson.toJson(config.config));
+
+    return camera;
+  }
+
+  /**
+   * Example pipeline.
+   */
+  public static class MyPipeline implements VisionPipeline {
+    public int val;
+
+    @Override
+    public void process(Mat mat) {
+      val += 1;
+    }
+  }
+
+  /**
+   * Main.
+   */
+  public static void main(String... args) {
+    if (args.length > 0) {
+      configFile = args[0];
+    }
+
+    // read configuration
+    if (!readConfig()) {
+      return;
+    }
+
+    // start NetworkTables
+    NetworkTableInstance ntinst = NetworkTableInstance.getDefault();
+    if (server) {
+      System.out.println("Setting up NetworkTables server");
+      ntinst.startServer();
+    } else {
+      System.out.println("Setting up NetworkTables client for team " + team);
+      ntinst.startClientTeam(team);
+    }
+
+    // start cameras
+    List<VideoSource> cameras = new ArrayList<>();
+    for (CameraConfig cameraConfig : cameraConfigs) {
+      cameras.add(startCamera(cameraConfig));
+    }
+
+    // start image processing on camera 0 if present
+    if (cameras.size() >= 1) {
+      VisionThread visionThread = new VisionThread(cameras.get(0),
+              new MyPipeline(), pipeline -> {
+        // do something with pipeline results
+      });
+      /* something like this for GRIP:
+      VisionThread visionThread = new VisionThread(cameras.get(0),
+              new GripPipeline(), pipeline -> {
+        ...
+      });
+       */
+      visionThread.start();
+    }
+
+    // loop forever
+    for (;;) {
+      try {
+        Thread.sleep(10000);
+      } catch (InterruptedException ex) {
+        return;
+      }
+    }
+  }
+}

deps/examples/python-multiCameraServer/multiCameraServer.py

@@ -44,7 +44,7 @@ class CameraConfig: pass
 
 team = None
 server = False
-cameras = []
+cameraConfigs = []
 
 """Report parse error."""
 def parseError(str):
@@ -70,7 +70,7 @@ def readCameraConfig(config):
 
     cam.config = config
 
-    cameras.append(cam)
+    cameraConfigs.append(cam)
     return True
 
 """Read configuration file."""
@@ -128,6 +128,8 @@ def startCamera(config):
 
     camera.setConfigJson(json.dumps(config.config))
 
+    return camera
+
 if __name__ == "__main__":
     if len(sys.argv) >= 2:
         configFile = sys.argv[1]
@@ -146,8 +148,9 @@ if __name__ == "__main__":
         ntinst.startClientTeam(team)
 
     # start cameras
-    for camera in cameras:
+    cameras = []
-        startCamera(camera)
+    for cameraConfig in cameraConfigs:
+        cameras.append(startCamera(cameraConfig))
 
     # loop forever
     while True: