Use a second camera and switch between them.

Also, blink out the state over the beacon.

Change-Id: If606dfed9ae64137f71429f1190f04d5dac2c4ec
diff --git a/aos/vision/events/udp.cc b/aos/vision/events/udp.cc
index 4c0437b..660342c 100644
--- a/aos/vision/events/udp.cc
+++ b/aos/vision/events/udp.cc
@@ -26,8 +26,8 @@
   return send(fd_.get(), data, size, 0);
 }
 
-RXUdpSocket::RXUdpSocket(int port)
-    : fd_(PCHECK(socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))) {
+int RXUdpSocket::SocketBindListenOnPort(int port) {
+  int fd = PCHECK(socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP));
   sockaddr_in bind_address;
   memset(&bind_address, 0, sizeof(bind_address));
 
@@ -35,10 +35,13 @@
   bind_address.sin_port = htons(port);
   bind_address.sin_addr.s_addr = htonl(INADDR_ANY);
 
-  PCHECK(bind(fd_.get(), reinterpret_cast<sockaddr *>(&bind_address),
+  PCHECK(bind(fd, reinterpret_cast<sockaddr *>(&bind_address),
               sizeof(bind_address)));
+  return fd;
 }
 
+RXUdpSocket::RXUdpSocket(int port) : fd_(SocketBindListenOnPort(port)) {}
+
 int RXUdpSocket::Recv(void *data, int size) {
   return PCHECK(recv(fd_.get(), static_cast<char *>(data), size, 0));
 }
diff --git a/aos/vision/events/udp.h b/aos/vision/events/udp.h
index ed4a8e7..9a23dab 100644
--- a/aos/vision/events/udp.h
+++ b/aos/vision/events/udp.h
@@ -30,6 +30,24 @@
   DISALLOW_COPY_AND_ASSIGN(TXUdpSocket);
 };
 
+// Send a protobuf.  Not RT (mallocs on send).
+template <typename PB>
+class ProtoTXUdpSocket {
+ public:
+  ProtoTXUdpSocket(const std::string &ip_addr, int port)
+      : socket_(ip_addr, port) {}
+
+  void Send(const PB &pb) {
+    ::std::string serialized_data;
+    pb.SerializeToString(&serialized_data);
+    socket_.Send(serialized_data.data(), serialized_data.size());
+  }
+
+ private:
+  TXUdpSocket socket_;
+  DISALLOW_COPY_AND_ASSIGN(ProtoTXUdpSocket);
+};
+
 // Simple wrapper around a receiving UDP socket.
 //
 // LOG(FATAL)s for all errors, including from Recv.
@@ -40,6 +58,8 @@
   // Returns the number of bytes received.
   int Recv(void *data, int size);
 
+  static int SocketBindListenOnPort(int port);
+
  private:
   ScopedFD fd_;
 
diff --git a/y2018/BUILD b/y2018/BUILD
index 67ad583..4edb57e 100644
--- a/y2018/BUILD
+++ b/y2018/BUILD
@@ -1,5 +1,6 @@
 load("//aos/downloader:downloader.bzl", "aos_downloader")
 load("//aos/build:queues.bzl", "queue_library")
+load("//tools/build_rules:protobuf.bzl", "proto_cc_library")
 
 aos_downloader(
     name = "download",
@@ -10,6 +11,7 @@
     start_srcs = [
         ":joystick_reader",
         ":wpilib_interface",
+        "//y2018/vision:vision_status",
         "//aos:prime_start_binaries",
         "//y2018/control_loops/drivetrain:drivetrain",
         "//y2018/actors:autonomous_action",
@@ -26,6 +28,7 @@
     start_srcs = [
         ":joystick_reader.stripped",
         ":wpilib_interface.stripped",
+        "//y2018/vision:vision_status.stripped",
         "//aos:prime_start_binaries_stripped",
         "//y2018/actors:autonomous_action.stripped",
         "//y2018/control_loops/drivetrain:drivetrain.stripped",
@@ -39,7 +42,8 @@
         "joystick_reader.cc",
     ],
     deps = [
-        ":status_light",
+        ":vision_proto",
+        "//aos/common:stl_mutex",
         "//aos/common:time",
         "//aos/common/actions:action_lib",
         "//aos/common/logging",
@@ -47,6 +51,7 @@
         "//aos/input:drivetrain_input",
         "//aos/input:joystick_input",
         "//aos/linux_code:init",
+        "//aos/vision/events:udp",
         "//frc971/autonomous:auto_queue",
         "//frc971/autonomous:base_autonomous_actor",
         "//frc971/control_loops/drivetrain:drivetrain_queue",
@@ -116,6 +121,7 @@
         "//third_party/Phoenix-frc-lib:phoenix",
         "//y2018:constants",
         "//y2018/control_loops/superstructure:superstructure_queue",
+        "//y2018/vision:vision_queue",
     ],
 )
 
@@ -124,4 +130,11 @@
     srcs = [
         "status_light.q",
     ],
+    visibility = ["//visibility:public"],
+)
+
+proto_cc_library(
+    name = "vision_proto",
+    src = "vision.proto",
+    visibility = ["//visibility:public"],
 )
diff --git a/y2018/control_loops/superstructure/BUILD b/y2018/control_loops/superstructure/BUILD
index 8fcba95..cc179d5 100644
--- a/y2018/control_loops/superstructure/BUILD
+++ b/y2018/control_loops/superstructure/BUILD
@@ -25,9 +25,12 @@
         ":superstructure_queue",
         "//aos/common/controls:control_loop",
         "//frc971/control_loops:queues",
+        "//frc971/control_loops/drivetrain:drivetrain_queue",
         "//y2018:constants",
+        "//y2018:status_light",
         "//y2018/control_loops/superstructure/arm",
         "//y2018/control_loops/superstructure/intake",
+        "//y2018/vision:vision_queue",
     ],
 )
 
diff --git a/y2018/control_loops/superstructure/superstructure.cc b/y2018/control_loops/superstructure/superstructure.cc
index 757b166..2098cd0 100644
--- a/y2018/control_loops/superstructure/superstructure.cc
+++ b/y2018/control_loops/superstructure/superstructure.cc
@@ -5,8 +5,11 @@
 #include "aos/common/controls/control_loops.q.h"
 #include "aos/common/logging/logging.h"
 #include "frc971/control_loops/control_loops.q.h"
+#include "frc971/control_loops/drivetrain/drivetrain.q.h"
 #include "y2018/constants.h"
 #include "y2018/control_loops/superstructure/intake/intake.h"
+#include "y2018/status_light.q.h"
+#include "y2018/vision/vision.q.h"
 
 namespace y2018 {
 namespace control_loops {
@@ -21,6 +24,17 @@
 constexpr double kMaxIntakeRollerVoltage = 12.0;
 }  // namespace
 
+void SendColors(float red, float green, float blue) {
+  auto new_status_light = status_light.MakeMessage();
+  new_status_light->red = red;
+  new_status_light->green = green;
+  new_status_light->blue = blue;
+
+  if (!new_status_light.Send()) {
+    LOG(ERROR, "Failed to send lights.\n");
+  }
+}
+
 Superstructure::Superstructure(
     control_loops::SuperstructureQueue *superstructure_queue)
     : aos::controls::ControlLoop<control_loops::SuperstructureQueue>(
@@ -237,6 +251,34 @@
     stuck_count_ = 0;
   }
   status->rotation_state = static_cast<uint32_t>(rotation_state_);
+
+  ::frc971::control_loops::drivetrain_queue.output.FetchLatest();
+
+  ::y2018::vision::vision_status.FetchLatest();
+  if (status->estopped) {
+    SendColors(0.5, 0.0, 0.0);
+  } else if (!y2018::vision::vision_status.get() ||
+             y2018::vision::vision_status.Age() > chrono::seconds(1)) {
+    SendColors(0.5, 0.5, 0.0);
+  } else if (rotation_state_ == RotationState::ROTATING_LEFT ||
+             rotation_state_ == RotationState::ROTATING_RIGHT) {
+    SendColors(0.5, 0.20, 0.0);
+  } else if (rotation_state_ == RotationState::STUCK) {
+    SendColors(0.5, 0.0, 0.5);
+  } else if (position->box_back_beambreak_triggered) {
+    SendColors(0.0, 0.0, 0.5);
+  } else if (position->box_distance < 0.2) {
+    SendColors(0.0, 0.5, 0.0);
+  } else if (::frc971::control_loops::drivetrain_queue.output.get() &&
+             ::std::max(::std::abs(::frc971::control_loops::drivetrain_queue
+                                       .output->left_voltage),
+                        ::std::abs(::frc971::control_loops::drivetrain_queue
+                                       .output->right_voltage)) > 11.5) {
+    SendColors(0.5, 0.0, 0.5);
+  } else {
+    SendColors(0.0, 0.0, 0.0);
+  }
+
   last_box_distance_ = clipped_box_distance;
 }
 
diff --git a/y2018/control_loops/superstructure/superstructure_lib_test.cc b/y2018/control_loops/superstructure/superstructure_lib_test.cc
index 639a683..d21d1ce 100644
--- a/y2018/control_loops/superstructure/superstructure_lib_test.cc
+++ b/y2018/control_loops/superstructure/superstructure_lib_test.cc
@@ -7,6 +7,7 @@
 
 #include "aos/common/controls/control_loop_test.h"
 #include "aos/common/queue.h"
+#include "frc971/control_loops/drivetrain/drivetrain.q.h"
 #include "frc971/control_loops/position_sensor_sim.h"
 #include "frc971/control_loops/team_number_test_environment.h"
 #include "gtest/gtest.h"
@@ -14,6 +15,8 @@
 #include "y2018/control_loops/superstructure/arm/dynamics.h"
 #include "y2018/control_loops/superstructure/arm/generated_graph.h"
 #include "y2018/control_loops/superstructure/intake/intake_plant.h"
+#include "y2018/status_light.q.h"
+#include "y2018/vision/vision.q.h"
 
 using ::frc971::control_loops::PositionSensorSimulator;
 
@@ -271,6 +274,9 @@
                               ".y2018.control_loops.superstructure.output",
                               ".y2018.control_loops.superstructure.status"),
         superstructure_(&superstructure_queue_) {
+    status_light.Clear();
+    ::y2018::vision::vision_status.Clear();
+    ::frc971::control_loops::drivetrain_queue.output.Clear();
     set_team_id(::frc971::control_loops::testing::kTeamNumber);
   }
 
diff --git a/y2018/joystick_reader.cc b/y2018/joystick_reader.cc
index 4e3103b..79056e2 100644
--- a/y2018/joystick_reader.cc
+++ b/y2018/joystick_reader.cc
@@ -2,26 +2,31 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
+#include <mutex>
 
 #include "aos/common/actions/actions.h"
 #include "aos/common/input/driver_station_data.h"
 #include "aos/common/logging/logging.h"
+#include "aos/common/stl_mutex.h"
 #include "aos/common/time.h"
 #include "aos/common/util/log_interval.h"
 #include "aos/input/drivetrain_input.h"
 #include "aos/input/joystick_input.h"
 #include "aos/linux_code/init.h"
+#include "aos/vision/events/udp.h"
 #include "frc971/autonomous/auto.q.h"
 #include "frc971/autonomous/base_autonomous_actor.h"
 #include "frc971/control_loops/drivetrain/drivetrain.q.h"
 #include "y2018/control_loops/drivetrain/drivetrain_base.h"
 #include "y2018/control_loops/superstructure/arm/generated_graph.h"
 #include "y2018/control_loops/superstructure/superstructure.q.h"
-#include "y2018/status_light.q.h"
+#include "y2018/vision.pb.h"
 
+using ::aos::monotonic_clock;
 using ::frc971::control_loops::drivetrain_queue;
 using ::y2018::control_loops::superstructure_queue;
-
+using ::aos::events::ProtoTXUdpSocket;
+using ::aos::events::RXUdpSocket;
 using ::aos::input::driver_station::ButtonLocation;
 using ::aos::input::driver_station::ControlBit;
 using ::aos::input::driver_station::JoystickAxis;
@@ -78,7 +83,7 @@
 
 class Reader : public ::aos::input::JoystickInput {
  public:
-  Reader() {
+  Reader() : video_tx_("10.9.71.179", 5000) {
     drivetrain_input_reader_ = DrivetrainInputReader::Make(
         DrivetrainInputReader::InputType::kPistol,
         ::y2018::control_loops::drivetrain::GetDrivetrainConfig());
@@ -110,17 +115,6 @@
     drivetrain_input_reader_->HandleDrivetrain(data);
   }
 
-  void SendColors(float red, float green, float blue) {
-    auto new_status_light = status_light.MakeMessage();
-    new_status_light->red = red;
-    new_status_light->green = green;
-    new_status_light->blue = blue;
-
-    if (!new_status_light.Send()) {
-      LOG(ERROR, "Failed to send lights.\n");
-    }
-  }
-
   void HandleTeleop(const ::aos::input::driver_station::Data &data) {
     if (!data.GetControlBit(ControlBit::kEnabled)) {
       action_queue_.CancelAllActions();
@@ -140,6 +134,11 @@
     new_superstructure_goal->intake.left_intake_angle = intake_goal_;
     new_superstructure_goal->intake.right_intake_angle = intake_goal_;
 
+    if (data.PosEdge(kIntakeIn) || data.PosEdge(kSmallBox) ||
+        data.PosEdge(kIntakeClosed)) {
+      vision_control_.set_high_video(false);
+    }
+
     if (data.IsPressed(kIntakeIn)) {
       // Turn on the rollers.
       new_superstructure_goal->intake.roller_voltage = 8.0;
@@ -151,14 +150,6 @@
       new_superstructure_goal->intake.roller_voltage = 0.0;
     }
 
-    if (superstructure_queue.position->box_back_beambreak_triggered) {
-      SendColors(0.0, 0.5, 0.0);
-    } else if (superstructure_queue.position->box_distance < 0.2) {
-      SendColors(0.0, 0.0, 0.5);
-    } else {
-      SendColors(0.0, 0.0, 0.0);
-    }
-
     if (data.IsPressed(kSmallBox)) {
       // Deploy the intake.
       if (superstructure_queue.position->box_back_beambreak_triggered) {
@@ -251,24 +242,33 @@
         }
       }
     } else if (data.PosEdge(kArmPickupBoxFromIntake)) {
+      vision_control_.set_high_video(false);
       arm_goal_position_ = arm::NeutralIndex();
     } else if (data.IsPressed(kDuck)) {
+      vision_control_.set_high_video(false);
       arm_goal_position_ = arm::DuckIndex();
     } else if (data.IsPressed(kArmNeutral)) {
+      vision_control_.set_high_video(false);
       arm_goal_position_ = arm::NeutralIndex();
     } else if (data.IsPressed(kArmUp)) {
+      vision_control_.set_high_video(true);
       arm_goal_position_ = arm::UpIndex();
     } else if (data.IsPressed(kArmFrontSwitch)) {
       arm_goal_position_ = arm::FrontSwitchIndex();
     } else if (data.IsPressed(kArmFrontExtraHighBox)) {
+      vision_control_.set_high_video(true);
       arm_goal_position_ = arm::FrontHighBoxIndex();
     } else if (data.IsPressed(kArmFrontHighBox)) {
+      vision_control_.set_high_video(true);
       arm_goal_position_ = arm::FrontMiddle2BoxIndex();
     } else if (data.IsPressed(kArmFrontMiddle2Box)) {
+      vision_control_.set_high_video(true);
       arm_goal_position_ = arm::FrontMiddle3BoxIndex();
     } else if (data.IsPressed(kArmFrontMiddle1Box)) {
+      vision_control_.set_high_video(true);
       arm_goal_position_ = arm::FrontMiddle1BoxIndex();
     } else if (data.IsPressed(kArmFrontLowBox)) {
+      vision_control_.set_high_video(true);
       arm_goal_position_ = arm::FrontLowBoxIndex();
     } else if (data.IsPressed(kArmBackExtraHighBox)) {
       arm_goal_position_ = arm::BackHighBoxIndex();
@@ -324,6 +324,8 @@
     if (!new_superstructure_goal.Send()) {
       LOG(ERROR, "Sending superstructure goal failed.\n");
     }
+
+    video_tx_.Send(vision_control_);
   }
 
  private:
@@ -358,11 +360,14 @@
   bool never_disabled_ = true;
 
   uint32_t arm_goal_position_ = 0;
+  VisionControl vision_control_;
 
   decltype(FrontPoints()) front_points_ = FrontPoints();
   decltype(BackPoints()) back_points_ = BackPoints();
 
   ::aos::common::actions::ActionQueue action_queue_;
+
+  ProtoTXUdpSocket<VisionControl> video_tx_;
 };
 
 }  // namespace joysticks
diff --git a/y2018/vision.proto b/y2018/vision.proto
new file mode 100644
index 0000000..04b3181
--- /dev/null
+++ b/y2018/vision.proto
@@ -0,0 +1,12 @@
+syntax = "proto2";
+
+package y2018;
+
+message VisionControl {
+  optional bool high_video = 1;
+}
+
+message VisionStatus {
+  optional uint32 high_frame_count = 1;
+  optional uint32 low_frame_count = 2;
+}
diff --git a/y2018/vision/BUILD b/y2018/vision/BUILD
index 11fb7c5..dfe5ebb 100644
--- a/y2018/vision/BUILD
+++ b/y2018/vision/BUILD
@@ -1,13 +1,43 @@
+load("//aos/build:queues.bzl", "queue_library")
+
 cc_binary(
-  name = "image_streamer",
-  srcs = ["image_streamer.cc"],
-  deps = [
-    "//aos/vision/events:socket_types",
-    '//aos/vision/events:epoll_events',
-    '//aos/vision/image:reader',
-    '//aos/vision/image:image_stream',
-    '//aos/vision/blob:codec',
-    '//aos/common/logging:logging',
-    '//aos/common/logging:implementations',
-  ],
+    name = "image_streamer",
+    srcs = ["image_streamer.cc"],
+    deps = [
+        "//aos/common/logging",
+        "//aos/common/logging:implementations",
+        "//aos/vision/blob:codec",
+        "//aos/vision/events:epoll_events",
+        "//aos/vision/events:socket_types",
+        "//aos/vision/events:udp",
+        "//aos/vision/image:image_stream",
+        "//aos/vision/image:reader",
+        "//third_party/gflags",
+        "//y2018:vision_proto",
+    ],
+)
+
+queue_library(
+    name = "vision_queue",
+    srcs = [
+        "vision.q",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+cc_binary(
+    name = "vision_status",
+    srcs = [
+        "vision_status.cc",
+    ],
+    visibility = ["//visibility:public"],
+    deps = [
+        ":vision_queue",
+        "//aos/common:time",
+        "//aos/common/logging",
+        "//aos/common/logging:queue_logging",
+        "//aos/linux_code:init",
+        "//aos/vision/events:udp",
+        "//y2018:vision_proto",
+    ],
 )
diff --git a/y2018/vision/exposure_2018.sh b/y2018/vision/exposure_2018.sh
index c96f5f0..bfcd31c 100755
--- a/y2018/vision/exposure_2018.sh
+++ b/y2018/vision/exposure_2018.sh
@@ -2,18 +2,20 @@
 
 set -e
 
-A=`ls /dev/video*`
 EXPOSURE='100'
 
 echo $SHELL
 
-echo $A
 
 # Michael added this one to try and have the exposer set correctly sooner.
 sleep 1
 echo Setting exposure again after 1 seconds
 
-v4l2-ctl --set-ctrl="exposure_absolute=$EXPOSURE" -d $A
+for CAMERA in /dev/video0 /dev/video1
+do
+  echo "${CAMERA}"
+  v4l2-ctl --set-ctrl="exposure_absolute=$EXPOSURE" -d "${CAMERA}"
+done
 
 echo Done setting exposure again after 1 seconds
 
@@ -21,8 +23,11 @@
 # Michael added this one to try and have the exposer set correctly sooner.
 sleep 5
 echo Setting exposure again after 5 seconds
-v4l2-ctl --set-ctrl="exposure_absolute=$EXPOSURE" -d $A
-
+for CAMERA in /dev/video0 /dev/video1
+do
+  echo "${CAMERA}"
+  v4l2-ctl --set-ctrl="exposure_absolute=$EXPOSURE" -d "${CAMERA}"
+done
 
 echo Done setting exposure again after 5 seconds
 
diff --git a/y2018/vision/image_streamer.cc b/y2018/vision/image_streamer.cc
index ce6f5e2..93f8c58 100644
--- a/y2018/vision/image_streamer.cc
+++ b/y2018/vision/image_streamer.cc
@@ -1,28 +1,41 @@
-#include "aos/vision/events/socket_types.h"
-#include "aos/vision/image/reader.h"
 #include "aos/vision/image/image_stream.h"
+
+#include <sys/stat.h>
+#include <deque>
+#include <fstream>
+#include <string>
+
 #include "aos/common/logging/implementations.h"
 #include "aos/common/logging/logging.h"
 #include "aos/vision/blob/codec.h"
-#include <fstream>
-#include <sys/stat.h>
-#include <deque>
-#include <string>
+#include "aos/vision/events/socket_types.h"
+#include "aos/vision/events/udp.h"
+#include "aos/vision/image/reader.h"
+#include "third_party/gflags/include/gflags/gflags.h"
+#include "y2018/vision.pb.h"
 
-using aos::events::TCPServer;
-using aos::events::DataSocket;
-using aos::vision::Int32Codec;
-using aos::vision::DataRef;
+using ::aos::events::DataSocket;
+using ::aos::events::RXUdpSocket;
+using ::aos::events::TCPServer;
+using ::aos::vision::DataRef;
+using ::aos::vision::Int32Codec;
+using ::aos::monotonic_clock;
+using ::y2018::VisionControl;
 
-aos::vision::DataRef mjpg_header = "HTTP/1.0 200 OK\r\n"\
-      "Server: YourServerName\r\n"\
-      "Connection: close\r\n"\
-      "Max-Age: 0\r\n"\
-      "Expires: 0\r\n"\
-      "Cache-Control: no-cache, private\r\n"\
-      "Pragma: no-cache\r\n"\
-      "Content-Type: multipart/x-mixed-replace; "\
-      "boundary=--boundary\r\n\r\n";
+DEFINE_bool(single_camera, true, "If true, only use video0");
+DEFINE_int32(camera0_exposure, 300, "Exposure for video0");
+DEFINE_int32(camera1_exposure, 300, "Exposure for video1");
+
+aos::vision::DataRef mjpg_header =
+    "HTTP/1.0 200 OK\r\n"
+    "Server: YourServerName\r\n"
+    "Connection: close\r\n"
+    "Max-Age: 0\r\n"
+    "Expires: 0\r\n"
+    "Cache-Control: no-cache, private\r\n"
+    "Pragma: no-cache\r\n"
+    "Content-Type: multipart/x-mixed-replace; "
+    "boundary=--boundary\r\n\r\n";
 
 struct Frame {
   std::string data;
@@ -58,11 +71,49 @@
   std::ofstream ofst_;
 };
 
+class UdpClient : public ::aos::events::EpollEvent {
+ public:
+  UdpClient(int port, ::std::function<void(void *, size_t)> callback)
+      : ::aos::events::EpollEvent(RXUdpSocket::SocketBindListenOnPort(port)),
+        callback_(callback) {}
+
+ private:
+  ::std::function<void(void *, size_t)> callback_;
+
+  void ReadEvent() override {
+    char data[1024];
+    size_t received_data_size = Recv(data, sizeof(data));
+    callback_(data, received_data_size);
+  }
+
+  size_t Recv(void *data, int size) {
+    return PCHECK(recv(fd(), static_cast<char *>(data), size, 0));
+  }
+};
+
+template <typename PB>
+class ProtoUdpClient : public UdpClient {
+ public:
+  ProtoUdpClient(int port, ::std::function<void(const PB &)> proto_callback)
+      : UdpClient(port, ::std::bind(&ProtoUdpClient::ReadData, this,
+                                    ::std::placeholders::_1,
+                                    ::std::placeholders::_2)),
+        proto_callback_(proto_callback) {}
+
+ private:
+  ::std::function<void(const PB &)> proto_callback_;
+
+  void ReadData(void *data, size_t size) {
+    PB pb;
+    pb.ParseFromArray(data, size);
+    proto_callback_(pb);
+  }
+};
+
 class MjpegDataSocket : public aos::events::SocketConnection {
  public:
-
-  MjpegDataSocket(aos::events::TCPServerBase *serv, int fd)
-      : aos::events::SocketConnection(serv, fd) {
+  MjpegDataSocket(aos::events::TCPServerBase *server, int fd)
+      : aos::events::SocketConnection(server, fd) {
     SetEvents(EPOLLOUT | EPOLLET);
   }
 
@@ -73,6 +124,12 @@
       NewDataToSend();
       events &= ~EPOLLOUT;
     }
+    // Other end hung up.  Ditch the connection.
+    if (events & EPOLLHUP) {
+      CloseConnection();
+      events &= ~EPOLLHUP;
+      return;
+    }
     if (events) {
       aos::events::EpollEvent::DirectEvent(events);
     }
@@ -124,9 +181,10 @@
     aos::vision::DataRef data = frame->data;
 
     size_t n_written = snprintf(data_header_tmp_, sizeof(data_header_tmp_),
-                                "--boundary\r\n"\
-                                "Content-type: image/jpg\r\n"\
-                                "Content-Length: %zu\r\n\r\n", data.size());
+                                "--boundary\r\n"
+                                "Content-type: image/jpg\r\n"
+                                "Content-Length: %zu\r\n\r\n",
+                                data.size());
     // This should never happen because the buffer should be properly sized.
     if (n_written == sizeof(data_header_tmp_)) {
       fprintf(stderr, "wrong sized buffer\n");
@@ -138,13 +196,11 @@
     NewDataToSend();
   }
 
-  void NewFrame(std::shared_ptr<Frame> frame) {
-    RasterFrame(std::move(frame));
-  }
+  void NewFrame(std::shared_ptr<Frame> frame) { RasterFrame(std::move(frame)); }
 
   void NewDataToSend() {
     while (!output_buffer_.empty()) {
-      auto& data = *output_buffer_.begin();
+      auto &data = *output_buffer_.begin();
 
       while (!data.empty()) {
         int len = send(fd(), data.data(), data.size(), MSG_NOSIGNAL);
@@ -178,16 +234,25 @@
   size_t match_i_ = 0;
 };
 
-using namespace aos::vision;
-class CameraStream : public ImageStreamEvent {
+class CameraStream : public ::aos::vision::ImageStreamEvent {
  public:
-  CameraStream(aos::vision::CameraParams params, 
-               const std::string &fname, TCPServer<MjpegDataSocket>* tcp_serv)
-      : ImageStreamEvent(fname, params), tcp_serv_(tcp_serv),
-        log_("./logging/blob_record_", ".dat") {}      
+  CameraStream(::aos::vision::CameraParams params, const ::std::string &fname,
+               TCPServer<MjpegDataSocket> *tcp_server, bool log,
+               ::std::function<void()> frame_callback)
+      : ImageStreamEvent(fname, params),
+        tcp_server_(tcp_server),
+        frame_callback_(frame_callback) {
+    if (log) {
+      log_.reset(new BlobLog("./logging/blob_record_", ".dat"));
+    }
+  }
 
-  void ProcessImage(DataRef data, aos::monotonic_clock::time_point tp) {
-    (void)tp;
+  void set_active(bool active) { active_ = active; }
+
+  bool active() const { return active_; }
+
+  void ProcessImage(DataRef data,
+                    monotonic_clock::time_point /*monotonic_now*/) {
     ++sampling;
     // 20 is the sampling rate.
     if (sampling == 20) {
@@ -199,36 +264,98 @@
         buf = Int32Codec::Write(&log_record[0], tmp_size);
         data.copy(buf, data.size());
       }
-      log_.WriteLogEntry(log_record);
+      if (log_) {
+        log_->WriteLogEntry(log_record);
+      }
       sampling = 0;
     }
 
-    auto frame = std::make_shared<Frame>(Frame{std::string(data)});
-    tcp_serv_->Broadcast([frame](MjpegDataSocket* event) {
-                         event->NewFrame(frame);
-                         });
+    if (active_) {
+      auto frame = std::make_shared<Frame>(Frame{std::string(data)});
+      tcp_server_->Broadcast(
+          [frame](MjpegDataSocket *event) { event->NewFrame(frame); });
+    }
+    frame_callback_();
   }
+
  private:
   int sampling = 0;
-  TCPServer<MjpegDataSocket>* tcp_serv_;
-  BlobLog log_;
+  TCPServer<MjpegDataSocket> *tcp_server_;
+  ::std::unique_ptr<BlobLog> log_;
+  ::std::function<void()> frame_callback_;
+  bool active_ = false;
 };
 
-int main() {
+int main(int argc, char ** argv) {
+  gflags::ParseCommandLineFlags(&argc, &argv, false);
   ::aos::logging::Init();
   ::aos::logging::AddImplementation(
       new ::aos::logging::StreamLogImplementation(stderr));
 
-  TCPServer<MjpegDataSocket> tcp_serv_(80);
-  aos::vision::CameraParams params;
-  params.set_exposure(100);
-  params.set_width(320);
-  params.set_height(240);
-  CameraStream camera(params, "/dev/video0", &tcp_serv_);
+  TCPServer<MjpegDataSocket> tcp_server_(80);
+  aos::vision::CameraParams params0;
+  params0.set_exposure(FLAGS_camera0_exposure);
+  params0.set_brightness(-40);
+  params0.set_width(320);
+  //params0.set_fps(10);
+  params0.set_height(240);
+
+  aos::vision::CameraParams params1 = params0;
+  params1.set_exposure(FLAGS_camera1_exposure);
+
+  ::y2018::VisionStatus vision_status;
+  ::aos::events::ProtoTXUdpSocket<::y2018::VisionStatus> status_socket(
+      "10.9.71.2", 5001);
+
+  ::std::unique_ptr<CameraStream> camera1;
+  ::std::unique_ptr<CameraStream> camera0(new CameraStream(
+      params0, "/dev/video0", &tcp_server_, true,
+      [&camera0, &camera1, &status_socket, &vision_status]() {
+        vision_status.set_low_frame_count(vision_status.low_frame_count() + 1);
+        LOG(INFO, "Got a frame cam0\n");
+        if (camera0->active()) {
+          status_socket.Send(vision_status);
+        }
+      }));
+  if (!FLAGS_single_camera) {
+    camera1.reset(new CameraStream(
+        // params,
+        // "/dev/v4l/by-path/platform-tegra-xhci-usb-0:3.1:1.0-video-index0",
+        params1, "/dev/video1", &tcp_server_, false,
+        [&camera0, &camera1, &status_socket, &vision_status]() {
+          vision_status.set_high_frame_count(vision_status.high_frame_count() +
+                                             1);
+          LOG(INFO, "Got a frame cam1\n");
+          if (camera1->active()) {
+            status_socket.Send(vision_status);
+          }
+        }));
+  }
+
+  ProtoUdpClient<VisionControl> udp_client(
+      5000, [&camera0, &camera1](const VisionControl &vision_control) {
+        LOG(INFO, "Got control packet\n");
+        if (camera1) {
+          camera0->set_active(!vision_control.high_video());
+          camera1->set_active(vision_control.high_video());
+        } else {
+          camera0->set_active(true);
+        }
+      });
+
+  // Default to camera0
+  camera0->set_active(true);
+  if (camera1) {
+    camera1->set_active(false);
+  }
 
   aos::events::EpollLoop loop;
-  loop.Add(&tcp_serv_);
-  loop.Add(&camera);
+  loop.Add(&tcp_server_);
+  loop.Add(camera0.get());
+  if (camera1) {
+    loop.Add(camera1.get());
+  }
+  loop.Add(&udp_client);
 
   printf("Running Camera\n");
   loop.Run();
diff --git a/y2018/vision/startup.sh b/y2018/vision/startup.sh
index 6cb211a..7122c01 100755
--- a/y2018/vision/startup.sh
+++ b/y2018/vision/startup.sh
@@ -30,25 +30,25 @@
 # echo All done setting exposure
 
 # echo "Starting target sender now."
-A=`ls /dev/video*`
 
-echo $SHELL
+for CAMERA in /dev/video0 /dev/video1
+do
+  echo $CAMERA
 
-echo $A
+  v4l2-ctl --set-ctrl="exposure_auto=1" -d $CAMERA
+  sleep 0.5
+  v4l2-ctl --set-ctrl="exposure_absolute=100" -d $CAMERA
+  sleep 0.5
 
-v4l2-ctl --set-ctrl="exposure_auto=1" -d $A
-sleep 0.5
-v4l2-ctl --set-ctrl="exposure_absolute=100" -d $A
-sleep 0.5
+  PATH="./;$PATH"
 
-PATH="./;$PATH"
-
-/root/camera_primer $A
+  /root/camera_primer $CAMERA
+done
 
 # Run a script to reset the exposure a few times and exit.
 /root/exposure_2018.sh &
 
-/root/image_streamer
+exec /root/image_streamer --single_camera=false
 #exec ./target_sender Practice
 #exec ./target_sender Comp
 #exec ./target_sender Spare
diff --git a/y2018/vision/vision.q b/y2018/vision/vision.q
new file mode 100644
index 0000000..a3b57ea
--- /dev/null
+++ b/y2018/vision/vision.q
@@ -0,0 +1,7 @@
+package y2018.vision;
+
+message VisionStatus {
+  uint32_t high_frame_count;
+  uint32_t low_frame_count;
+};
+queue VisionStatus vision_status;
diff --git a/y2018/vision/vision_status.cc b/y2018/vision/vision_status.cc
new file mode 100644
index 0000000..e8ac6db
--- /dev/null
+++ b/y2018/vision/vision_status.cc
@@ -0,0 +1,42 @@
+#include <netdb.h>
+
+#include "aos/common/logging/logging.h"
+#include "aos/common/logging/queue_logging.h"
+#include "aos/common/time.h"
+#include "aos/linux_code/init.h"
+#include "aos/vision/events/udp.h"
+#include "y2018/vision.pb.h"
+#include "y2018/vision/vision.q.h"
+
+namespace y2018 {
+namespace vision {
+
+using aos::monotonic_clock;
+
+int Main() {
+  ::aos::events::RXUdpSocket video_rx(5001);
+  char data[65507];
+  ::y2018::VisionStatus status;
+
+  while (true) {
+    const ssize_t rx_size = video_rx.Recv(data, sizeof(data));
+    if (rx_size > 0) {
+      status.ParseFromArray(data, rx_size);
+      auto new_vision_status = vision_status.MakeMessage();
+      new_vision_status->high_frame_count = status.high_frame_count();
+      new_vision_status->low_frame_count = status.low_frame_count();
+      LOG_STRUCT(DEBUG, "vision", *new_vision_status);
+      if (!new_vision_status.Send()) {
+        LOG(ERROR, "Failed to send vision information\n");
+      }
+    }
+  }
+}
+
+}  // namespace vision
+}  // namespace y2018
+
+int main(int /*argc*/, char ** /*argv*/) {
+  ::aos::InitNRT();
+  ::y2018::vision::Main();
+}
diff --git a/y2018/wpilib_interface.cc b/y2018/wpilib_interface.cc
index f204605..ec54da8 100644
--- a/y2018/wpilib_interface.cc
+++ b/y2018/wpilib_interface.cc
@@ -52,6 +52,7 @@
 #include "y2018/constants.h"
 #include "y2018/control_loops/superstructure/superstructure.q.h"
 #include "y2018/status_light.q.h"
+#include "y2018/vision/vision.q.h"
 
 #ifndef M_PI
 #define M_PI 3.14159265358979323846
@@ -660,35 +661,66 @@
         LOG_STRUCT(DEBUG, "pneumatics info", to_log);
       }
 
-      static double last_red = -1.0;
-      static double last_green = -1.0;
-      static double last_blue = -1.0;
       status_light.FetchLatest();
-      if (status_light.get()) {
-        LOG_STRUCT(DEBUG, "writing", *status_light);
-        // Not sure which of these is red vs green. We're not ready to use
-        // either, so just turn them off.
-        if (status_light->green != last_green) {
-          canifier_.SetLEDOutput(1.0 - status_light->green,
-                                 ::ctre::phoenix::CANifier::LEDChannelA);
-          last_green = status_light->green;
+      // If we don't have a light request (or it's an old one), we are borked.
+      // Flash the red light slowly.
+      if (!status_light.get() ||
+          status_light.Age() > chrono::milliseconds(100)) {
+        StatusLight color;
+        color.red = 0.0;
+        color.green = 0.0;
+        color.blue = 0.0;
+
+        ::y2018::vision::vision_status.FetchLatest();
+        ++light_flash_;
+        if (light_flash_ > 10) {
+          color.red = 0.5;
+        } else if (!y2018::vision::vision_status.get() ||
+                   y2018::vision::vision_status.Age() > chrono::seconds(1)) {
+          color.red = 0.5;
+          color.green = 0.5;
         }
 
-        if (status_light->blue != last_blue) {
-          canifier_.SetLEDOutput(1.0 - status_light->blue,
-                                 ::ctre::phoenix::CANifier::LEDChannelB);
-          last_blue = status_light->blue;
+        if (light_flash_ > 20) {
+          light_flash_ = 0;
         }
 
-        if (status_light->red != last_red) {
-          canifier_.SetLEDOutput(1.0 - status_light->red,
-                                 ::ctre::phoenix::CANifier::LEDChannelC);
-          last_red = status_light->red;
-        }
+        LOG_STRUCT(DEBUG, "color", color);
+        SetColor(color);
+      } else {
+        LOG_STRUCT(DEBUG, "color", *status_light);
+        SetColor(*status_light);
       }
     }
   }
 
+  void SetColor(const StatusLight &status_light) {
+    // Save CAN bandwidth and CPU at the cost of RT.  Only change the light when
+    // it actually changes.  This is pretty low priority anyways.
+    static int time_since_last_send = 0;
+    ++time_since_last_send;
+    if (time_since_last_send > 10) {
+      time_since_last_send = 0;
+    }
+    if (status_light.green != last_green_ || time_since_last_send == 0) {
+      canifier_.SetLEDOutput(1.0 - status_light.green,
+                             ::ctre::phoenix::CANifier::LEDChannelB);
+      last_green_ = status_light.green;
+    }
+
+    if (status_light.blue != last_blue_ || time_since_last_send == 0) {
+      canifier_.SetLEDOutput(1.0 - status_light.blue,
+                             ::ctre::phoenix::CANifier::LEDChannelA);
+      last_blue_ = status_light.blue;
+    }
+
+    if (status_light.red != last_red_ || time_since_last_send == 0) {
+      canifier_.SetLEDOutput(1.0 - status_light.red,
+                             ::ctre::phoenix::CANifier::LEDChannelC);
+      last_red_ = status_light.red;
+    }
+  }
+
   void Quit() { run_ = false; }
 
  private:
@@ -705,6 +737,12 @@
   ::ctre::phoenix::CANifier canifier_{0};
 
   ::std::atomic<bool> run_{true};
+
+  double last_red_ = -1.0;
+  double last_green_ = -1.0;
+  double last_blue_ = -1.0;
+
+  int light_flash_ = 0;
 };
 
 class DrivetrainWriter : public ::frc971::wpilib::LoopOutputHandler {