Add OpenCV and FFMPEG to CMake

CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.15)
 project (
     RoboMasterSDK
     VERSION 2.0.0
-    LANGUAGES C
+    LANGUAGES C CXX
 )
 
 set_property(GLOBAL PROPERTY C_STANDARD 17)
@@ -30,19 +30,27 @@ target_include_directories(robomaster
     include
 )
 
-include(FetchContent)
+find_package(SDL2 REQUIRED)
-FetchContent_Declare (
+find_package(OpenCV REQUIRED)
-    SDL2
+find_package(PkgConfig REQUIRED)
-    GIT_REPOSITORY https://github.com/libsdl-org/SDL
+
-    GIT_TAG release-2.0.20
+pkg_check_modules(FFMPEG REQUIRED IMPORTED_TARGET libavcodec libavformat libavutil libswscale)
-    GIT_SHALLOW TRUE
-)
-FetchContent_MakeAvailable(SDL2)
 
 add_executable(robomasterapp
-    src/sdl.c
+    src/sdl.cpp
 )
 target_link_libraries(robomasterapp
     robomaster
-    SDL2-static
+    SDL2::SDL2
+    ${OpenCV_LIBS}
+    PkgConfig::FFMPEG
+)
+
+add_executable(stream
+    src/stream.cpp
+)
+target_link_libraries(stream
+    SDL2::SDL2
+    ${OpenCV_LIBS}
+    PkgConfig::FFMPEG
 )

include/camera.h

@@ -38,3 +38,28 @@ stream_ctrl (
 		enum STREAMRESOLUTION res,
 		enum STREAMCTRL ctrl );
 
+static const uint8_t VISION_HOST = 17;
+static const uint8_t VISION_INDEX = 7;
+
+#define VISION_DETECT_ENABLE_CMD 0xA30A
+
+#define VISION_DETECT_ENABLE_PERSON 2
+#define VISION_DETECT_ENABLE_GESTURE 4
+#define VISION_DETECT_ENABLE_LINE 16
+#define VISION_DETECT_ENABLE_MARKER 32
+#define VISION_DETECT_ENABLE_ROBOT 128
+void
+vision_enable (
+		union Request* req,
+        uint16_t seq,
+        bool ack );
+
+#define VISION_DETECT_INFO_CMD 0xA40A
+enum VISIONTYPE {
+    VISIONTYPE_SHOULDER,
+    VISIONTYPE_PERSON,
+    VISIONTYPE_GESTURE,
+    VISIONTYPE_LINE,
+    VISIONTYPE_MARKER,
+    VISIONTYPE_ROBOT
+};

include/gimbal.h

@@ -18,3 +18,14 @@ gimbal_ctrl_speed (
 		int16_t p,
 		int16_t y,
 		int16_t r );
+
+#define GIMBAL_ROTATE_CMD 0xb03f
+void
+gimbal_rotate (
+		union Request* req,
+        uint16_t seq,
+        bool ack,
+		int16_t p,
+		int16_t y );
+
+#define GIMBAL_ACTION_PUSH_CMD 0xb13f

include/message.h

@@ -280,6 +280,122 @@ struct PACKED StreamCtrlResp {
     struct Footer footer;
 };
 
+struct PACKED VisionRect {
+    union {
+        struct {
+            float x;
+            float y;
+            float w;
+            float h;
+            uint32_t info;
+        } rect;
+        struct {
+            float x;
+            float y;
+            float theta;
+            float c;
+            uint32_t info;
+        } line;
+        struct {
+            float x;
+            float y;
+            float w;
+            float h;
+            uint16_t info;
+            uint16_t distance;
+        } marker;
+    };
+};
+
+struct PACKED VisionDetectInfo {
+    struct Header header;
+    uint8_t type;
+    uint8_t status;
+    uint16_t errcode;
+    uint8_t count;
+    struct VisionRect rects[];
+};
+
+struct PACKED GimbalActionPush {
+    struct Header header;
+    uint8_t id;
+    uint8_t progress;
+    uint8_t state;
+    int16_t yaw;
+    int16_t roll;
+    int16_t pitch;
+};
+
+struct PACKED GimbalRotateReq {
+    struct Header header;
+    uint8_t id;
+
+    //union {
+        uint8_t control_bitfield;
+    //    struct {
+    //        // always 0 for start
+    //        uint8_t control : 1;
+    //        uint8_t frequency : 2;
+    //    };
+    //};
+
+    //union {
+        uint8_t coord_bitfield;
+    //    struct {
+    //        uint8_t coordinate : 3;
+    //        // always true
+    //        uint8_t pitch_valid : 1;
+    //        // always false
+    //        uint8_t roll_valid : 1;
+    //        // always true
+    //        uint8_t yaw_valid : 1;
+    //    };
+    //};
+
+    union {
+        int16_t yaw;
+        struct {
+            int8_t l_yaw;
+            int8_t h_yaw;
+        };
+    };
+    int16_t roll;
+    union {
+        int16_t pitch;
+        struct {
+            int8_t l_pitch;
+            int8_t h_pitch;
+        };
+    };
+
+    uint16_t error;
+    uint16_t yaw_speed;
+    uint16_t roll_speed;
+    uint16_t pitch_speed;
+
+    struct Footer footer;
+};
+
+struct PACKED GimbalRotateResp {
+    struct Header header;
+    uint8_t retcode;
+    uint8_t accept;
+    struct Footer footer;
+};
+
+struct PACKED VisionDetectEnableReq {
+    struct Header header;
+    uint16_t type;
+    struct Footer footer;
+};
+
+struct PACKED VisionDetectEnableResp {
+    struct Header header;
+    uint8_t retcode;
+    uint16_t error;
+    struct Footer footer;
+};
+
 union Request {
     struct Header header;
     struct SetSdkConnectionReq sdkconn;
@@ -295,6 +411,8 @@ union Request {
     struct GimbalCtrlSpeedReq gimbspeed;
     struct BlasterFireReq blaster;
     struct StreamCtrlReq stream;
+    struct VisionDetectEnableReq enablevision;
+    struct GimbalRotateReq gimbalrot;
 };
 union Response {
     struct Header header;
@@ -311,11 +429,27 @@ union Response {
     struct GimbalCtrlSpeedResp gimbspeed;
     struct BlasterFireResp blaster;
     struct StreamCtrlResp stream;
+    struct VisionDetectEnableResp enablevision;
+    struct GimbalRotateResp gimbalrot;
+};
+
+union Push {
+    struct GimbalActionPush gimbalaction;
+    struct VisionDetectInfo vision;
 };
+
 union Message {
     struct Header header;
     union Request req;
     union Response resp;
+    union Push push;
+};
+
+enum ACTIONSTATE {
+    ACTION_RUNNING,
+    ACTION_SUCCEEDED,
+    ACTION_FAILED,
+    ACTION_STARTED
 };
 
 enum MESSAGEERR {

include/roboeasy.h

@@ -1,11 +1,28 @@
 #pragma once
 
+#include "message.h"
+
 #include <stdbool.h>
 
 // Handle for the high level robot interface
 struct RobotImp;
 typedef struct RobotImp* Robot;
 
+#define FRAGMENT_MESSAGE 1
+#define FRAGMENT_RECTANGLE 2
+#define FRAGMENT_LINE 3
+#define FRAGMENT_MARKER 4
+
+struct Fragment {
+    int type;
+    union {
+        union Message message;
+        struct VisionRect rect;
+    };
+};
+
+int robot_poll(Robot robot, struct Fragment* fragment);
+
 /*
  * Return a handle to the high level robot interface, or NULL on error.
  */
@@ -42,6 +59,8 @@ int robot_stop(Robot robot);
  */
 int robot_aim(Robot, float p, float y);
 
+int robot_target(Robot robot, float pitch, float yaw);
+
 /*
  * Set the velocity of the robot chassis. A packet will be sent to the robot on
  * the next ready tick of the work function.

include/robomaster.h

@@ -1,8 +1,8 @@
 #pragma once
 
 // Public stuff
-struct Client;
+struct ClientImp;
-typedef struct Client* Client;
+typedef struct ClientImp* Client;
 
 #include "message.h"
 #include "chassis.h"

src/client.h

@@ -2,7 +2,7 @@
 
 #include <stdint.h>
 
-struct Client {
+struct ClientImp {
 
     uint16_t seq;
 

src/connection.c

@@ -41,6 +41,10 @@ message_length(int cmd) {
             return sizeof(struct BlasterFireReq);
         case STREAM_CTRL_CMD:
             return sizeof(struct StreamCtrlReq);
+        case VISION_DETECT_ENABLE_CMD:
+            return sizeof(struct VisionDetectEnableReq);
+        case GIMBAL_ROTATE_CMD:
+            return sizeof(struct GimbalRotateReq);
         default:
             return 0;
     }
@@ -63,11 +67,14 @@ message_module(int cmd) {
         case CHASSIS_SPEED_MODE_CMD:
             return host2byte(CHASSIS_HOST, CHASSIS_INDEX);
         case GIMBAL_CTRL_SPEED_CMD:
+        case GIMBAL_ROTATE_CMD:
             return host2byte(GIMBAL_HOST, GIMBAL_INDEX);
         case BLASTER_FIRE_CMD:
             return host2byte(BLASTER_HOST, BLASTER_INDEX);
         case STREAM_CTRL_CMD:
             return host2byte(STREAM_HOST, STREAM_INDEX);
+        case VISION_DETECT_ENABLE_CMD:
+            return host2byte(VISION_HOST, VISION_INDEX);
         default:
             return 0;
     }
@@ -120,7 +127,7 @@ connection_new(unsigned int source_port, const char* source_ip, unsigned int des
 }
 
 struct Connection*
-connection_poll_ready(struct Client* client) {
+connection_poll_ready(struct ClientImp* client) {
 
     // Return a null connection if no sockets have been opened
     if(max_fd < 0)

src/connection.h

@@ -16,7 +16,7 @@ struct Connection*
 connection_new(unsigned int source_port, const char* source_ip, unsigned int dest_port, const char* dest_ip);
 
 struct Connection*
-connection_poll_ready(struct Client* client);
+connection_poll_ready(struct ClientImp* client);
 
 void
 connection_read(struct Connection* connection, union Message* resp);

src/message.c

@@ -1,9 +1,14 @@
 #include "message.h"
+#include "camera.h" // FIXME: hack
 #include "crc.h"
 
 enum MESSAGEERR
 message_validate(const union Message* message) {
 
+    // FIXME: hack
+    if(message->header.cmd == VISION_DETECT_INFO_CMD)
+        return MESSAGEERR_NONE;
+
     uint16_t length = message->header.length & 0x1FFF & ~0x400;
 
     if(message->header.crc != crc8(message, 3))

src/modules/camera.c

@@ -17,4 +17,12 @@ stream_ctrl (
     req_finalize(seq, STREAM_CTRL_CMD, ack, req);
 }
 
+void
+vision_enable (
+		union Request* req,
+        uint16_t seq,
+        bool ack ) {
+    req->enablevision.type = VISION_DETECT_ENABLE_PERSON;
+    req_finalize(seq, VISION_DETECT_ENABLE_CMD, ack, req);
+}
 

src/modules/gimbal.c

@@ -16,3 +16,35 @@ gimbal_ctrl_speed (
     req->gimbspeed.ctrl = 0xDC;
     req_finalize(seq, GIMBAL_CTRL_SPEED_CMD, ack, req);
 }
+
+void
+gimbal_rotate (
+		union Request* req,
+        uint16_t seq,
+        bool ack,
+		int16_t p,
+		int16_t y ) {
+    //req->gimbalrot.coordinate = 1;
+    //req->gimbalrot.yaw_valid = 1;
+    //req->gimbalrot.pitch_valid = 1;
+    //req->gimbalrot.roll_valid = 0;
+    req->gimbalrot.coord_bitfield = 0;
+    req->gimbalrot.coord_bitfield = 1 | 0 << 1 | 1 << 2 | 1 << 3;
+
+    //req->gimbalrot.frequency = 2;
+    //req->gimbalrot.control = 0;
+    req->gimbalrot.control_bitfield = 0;
+    req->gimbalrot.control_bitfield = 0 | 1 << 2;
+
+    req->gimbalrot.id = 33;
+    req->gimbalrot.yaw = 0;
+    req->gimbalrot.yaw = y;// >> 8;//(y >> 8 | y << 8);
+    req->gimbalrot.roll = 0;
+    req->gimbalrot.pitch = 0;
+    req->gimbalrot.pitch = p;// >> 8;//(p >> 8 | y << 8);
+    req->gimbalrot.error = 0;
+    req->gimbalrot.yaw_speed = 15;
+    req->gimbalrot.roll_speed = 0;
+    req->gimbalrot.pitch_speed = 15;
+    req_finalize(seq, GIMBAL_ROTATE_CMD, ack, req);
+}

src/robo.c

@@ -4,12 +4,23 @@
 
 #include <string.h>
 #include <stdlib.h>
+#include <math.h>
 
 #include <stdio.h>
 
+struct FragmentLink {
+    struct Fragment fragment;
+    struct FragmentLink *next;
+};
+
 struct RobotImp {
 
-    struct Client* client;
+    struct {
+        struct FragmentLink *head;
+        struct FragmentLink *free;
+    } frag_queue;
+
+    struct ClientImp* client;
     uint16_t seq;
 
     int16_t wheels[4];
@@ -21,6 +32,10 @@ struct RobotImp {
     int16_t gimbal[2];
     bool dirty_gimbal;
 
+    int16_t pitch;
+    int16_t yaw;
+    bool dirty_target;
+
     bool dirty_blaster;
 
     bool stream_state;
@@ -77,6 +92,25 @@ robot_aim(Robot robot, float p, float y) {
     return 1;
 }
 
+int
+robot_target(Robot robot, float pitch, float yaw) {
+    // Get the FOV angle of the point in radians
+    float FOV = 120 * (M_PI / 180);
+    yaw = yaw * (FOV / 2);
+    pitch = pitch * (FOV / 2);
+
+    // Convert to degrees
+    yaw = yaw * (180 / M_PI);
+    pitch = pitch * (180 / M_PI);
+
+    // Convert for Robomaster
+    robot->yaw = yaw * 10;
+    robot->pitch = -pitch * 10;
+
+    robot->dirty_target = true;
+    return 1;
+};
+
 int
 robot_led(Robot robot, unsigned char r, unsigned char g, unsigned char b) {
     robot->colors[0] = r;
@@ -98,6 +132,61 @@ robot_heartbeat(Robot robot) {
 
 }
 
+inline
+static
+void
+enqueue_fragment (
+        Robot robot,
+        const struct Fragment fragment ) {
+
+    struct FragmentLink *link;
+    if(robot->frag_queue.free) {
+        link = robot->frag_queue.free;
+        robot->frag_queue.free = link->next;
+    } else {
+        link = malloc(sizeof(struct FragmentLink));
+        link->next = NULL;
+    }
+
+    link->fragment = fragment;
+
+    if(robot->frag_queue.head) {
+        robot->frag_queue.head->next = link;
+    } else {
+        robot->frag_queue.head = link;
+    }
+
+}
+
+inline
+static
+void
+dequeue_fragment (
+        Robot robot,
+        struct Fragment *fragment ) {
+
+    fragment->type = 0;
+    if(!robot->frag_queue.head)
+        return;
+
+    struct FragmentLink *link = robot->frag_queue.head;
+    *fragment = link->fragment;
+
+    robot->frag_queue.head = link->next;
+    link->next = NULL;
+    if(robot->frag_queue.free) {
+        robot->frag_queue.free->next = link;
+    } else {
+        robot->frag_queue.free = link;
+    }
+
+}
+
+int robot_poll(Robot robot, struct Fragment* fragment) {
+    dequeue_fragment(robot, fragment);
+    return fragment->type;
+}
+
 int
 robot_work(Robot robot) {
 
@@ -156,7 +245,7 @@ robot_work(Robot robot) {
 
         case SETTING_MOVEMENT_MODE:
         {
-            set_robot_mode(&req, robot->seq++, true, MOVEMENTMODE_FREE);
+            set_robot_mode(&req, robot->seq++, true, MOVEMENTMODE_GIMBAL_LEAD);
             req_send(robot->client->dev_conn, &req);
             robot->state = WAITING;
             break;
@@ -191,6 +280,14 @@ robot_work(Robot robot) {
                 req_send(robot->client->dev_conn, &req);
                 robot->dirty_gimbal = false;
             }
+            if(robot->dirty_target) {
+                gimbal_rotate (
+                        &req, robot->seq++, true,
+                        robot->pitch,
+                        robot->yaw );
+                req_send(robot->client->dev_conn, &req);
+                robot->dirty_target = false;
+            }
             if(robot->dirty_colors) {
                 set_system_led (
                         &req, robot->seq++, false,
@@ -241,9 +338,38 @@ robot_work(Robot robot) {
 
     union Message resp;
     poll_message(robot->client, &resp);
+    if(resp.header.cmd) {
+        const struct Fragment fragment = {
+            .type = FRAGMENT_MESSAGE,
+            .message = resp
+        };
+        enqueue_fragment(robot, fragment);
+    }
     switch(resp.header.cmd) {
         case 0:
             break;
+        case VISION_DETECT_INFO_CMD:
+            // enqueue rectangles
+            for(int i = 0; i < resp.push.vision.count; i++) {
+                int type;
+                switch(resp.push.vision.type) {
+                    case VISIONTYPE_SHOULDER:
+                    case VISIONTYPE_PERSON:
+                    case VISIONTYPE_GESTURE:
+                    case VISIONTYPE_ROBOT:
+                        type = FRAGMENT_RECTANGLE;
+                    case VISIONTYPE_LINE:
+                        type = FRAGMENT_LINE;
+                    case VISIONTYPE_MARKER:
+                        type = FRAGMENT_MARKER;
+                }
+                const struct Fragment fragment = {
+                    .type = type,
+                    .rect = resp.push.vision.rects[i]
+                };
+                enqueue_fragment(robot, fragment);
+            }
+            break;
         case SET_SDK_CONNECTION_CMD:
             // TODO: Do more with this
             if(resp.resp.sdkconn.retcode) {

src/robomaster.c

@@ -8,8 +8,8 @@
 #include <string.h>
 
 Client client_new() {
-    struct Client* client = malloc(sizeof(struct Client));
+    struct ClientImp* client = malloc(sizeof(struct ClientImp));
-    memset(client, 0, sizeof(struct Client));
+    memset(client, 0, sizeof(struct ClientImp));
     // TODO: Make this configurable
     return client;
 }

src/sdl.c

@@ -1,140 +0,0 @@
-#include "roboeasy.h"
-#include "SDL2/SDL.h"
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdbool.h>
-
-struct {
-    unsigned char r;
-    unsigned char g;
-    unsigned char b;
-} const colors[] = {
-    {0xFF, 0x00, 0x00},
-    {0x00, 0xFF, 0x00},
-    {0x00, 0x00, 0xFF}
-};
-int color = 0;
-
-float pitch = 0, yaw = 0;
-float x = 0, y = 0, z = 0;
-static Uint32 drive_timer_handler(Uint32 interval, void* param) {
-    robot_drive((Robot)param, x, y, z);
-    robot_aim((Robot)param, pitch, yaw);
-    return 75;
-}
-static Uint32 heartbeat_timer_handler(Uint32 interval, void* param) {
-    robot_heartbeat((Robot)param);
-    return 1000;
-}
-
-int main(int argc, char* argv[]) {
-    if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
-        fprintf(stderr, "%s", SDL_GetError());
-        return 1;
-    }
-    printf("Detected %d joysticks\n", SDL_NumJoysticks());
-    SDL_Joystick* joystick = NULL;
-    if(SDL_NumJoysticks() > 0) {
-        joystick = SDL_JoystickOpen(0);
-    }
-    SDL_Window* win = SDL_CreateWindow(
-		    "Robomaster",
-		    SDL_WINDOWPOS_UNDEFINED,
-		    SDL_WINDOWPOS_UNDEFINED,
-		    800, 300,
-		    SDL_WINDOW_RESIZABLE );
-    if(!win) {
-        fprintf(stderr, "%s", SDL_GetError());
-        return 1;
-    }
-
-    Robot robot = robot_new();
-    robot_init(robot);
-    robot_stream(robot, true);
-
-    SDL_AddTimer(75, drive_timer_handler, robot);
-    SDL_AddTimer(1000, heartbeat_timer_handler, robot);
-
-    int h, w;
-    SDL_GetWindowSize(win, &w, &h);
-
-    while(robot_work(robot)) {
-        SDL_Event event;
-        while(SDL_PollEvent(&event)) {
-            switch(event.type) {
-                case SDL_KEYUP:
-                case SDL_KEYDOWN:
-                    switch(event.key.keysym.scancode) {
-                        case SDL_SCANCODE_Q:
-                            z = event.type == SDL_KEYUP ? 0 : 0.25;
-                            break;
-                        case SDL_SCANCODE_E:
-                            z = event.type == SDL_KEYUP ? 0 : -0.25;
-                            break;
-                        case SDL_SCANCODE_LEFT:
-                        case SDL_SCANCODE_A:
-                            x = event.type == SDL_KEYUP ? 0 : 0.25;
-                            break;
-                        case SDL_SCANCODE_RIGHT:
-                        case SDL_SCANCODE_D:
-                            x = event.type == SDL_KEYUP ? 0 : -0.25;
-                            break;
-                        case SDL_SCANCODE_UP:
-                        case SDL_SCANCODE_W:
-                            y = event.type == SDL_KEYUP ? 0 : 0.25;
-                            break;
-                        case SDL_SCANCODE_DOWN:
-                        case SDL_SCANCODE_S:
-                            y = event.type == SDL_KEYUP ? 0 : -0.25;
-                            break;
-                        case SDL_SCANCODE_SPACE:
-                            robot_led(robot, colors[color].r, colors[color].g, colors[color].b);
-                            color = (color + 1) % 3;
-                            break;
-                        case SDL_SCANCODE_RETURN:
-                            robot_blast(robot);
-                            break;
-                        default: break;
-		            }
-                    break;
-                case SDL_MOUSEMOTION:
-                    yaw = (float)event.motion.xrel;
-                    pitch = (float)event.motion.yrel;
-                    break;
-                case SDL_JOYAXISMOTION:
-                    switch(event.jaxis.axis) {
-                        case 0:
-                            x = (float)event.jaxis.value / 32767;
-                            break;
-                        case 1:
-                            y = (float)event.jaxis.value / 32767;
-                            break;
-                        case 4:
-                            z = (float)event.jaxis.value / 32767 / 2;
-                            break;
-                        case 2:
-                            yaw = (float)event.jaxis.value / 32767;
-                            break;
-                        case 3:
-                            pitch = (float)event.jaxis.value / 32767;
-                            break;
-                        default:
-                            printf("axis: %d\n", event.jaxis.axis);
-                            break;
-                    }
-                    break;
-                case SDL_WINDOWEVENT:
-                    if(event.window.event != SDL_WINDOWEVENT_CLOSE) break;
-                case SDL_QUIT:
-                    robot_stop(robot);
-                default: break;
-	        }
-	    }
-    }
-
-    SDL_JoystickClose(joystick);
-    SDL_Quit();
-    return 0;
-}
-

src/sdl.cpp

@@ -0,0 +1,417 @@
+extern "C" {
+#include "robomaster.h"
+#include "roboeasy.h"
+#include <libavcodec/avcodec.h>
+#include <libavformat/avformat.h>
+#include <libswscale/swscale.h>
+#include <libavutil/imgutils.h>
+}
+
+#include <SDL2/SDL.h>
+#include <opencv2/opencv.hpp>
+#include <opencv2/dnn/dnn.hpp>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <thread>
+#include <mutex>
+
+struct {
+    unsigned char r;
+    unsigned char g;
+    unsigned char b;
+} const colors[] = {
+    {0xFF, 0x00, 0x00},
+    {0x00, 0xFF, 0x00},
+    {0x00, 0x00, 0xFF}
+};
+int color = 0;
+
+float x = 0, y = 0, z = 0;
+int target_x = 0, target_y = 0;
+int yaw_cur = 0, pitch_cur = 0;
+static Uint32 drive_timer_handler(Uint32 interval, void* param) {
+    robot_drive((Robot)param, x, y, z);
+    return 75;
+}
+static Uint32 heartbeat_timer_handler(Uint32 interval, void* param) {
+    robot_heartbeat((Robot)param);
+    return 1000;
+}
+
+std::mutex mtx;
+cv::Mat img;
+std::vector<cv::Rect> found;
+std::vector<double> weights;
+unsigned target;
+
+bool stop = false;
+bool track = false;
+
+static void processFrameThread(Robot robot) {
+    cv::dnn::Net net = cv::dnn::readNet("yolov3-tiny.weights", "yolov3-tiny.cfg");
+
+    while(!stop) {
+        std::unique_lock<std::mutex> lock(mtx);
+
+        if(!img.empty()) {
+            found.clear();
+            weights.clear();
+            cv::Mat blob = cv::dnn::blobFromImage(img, 1/255.0, cv::Size(416, 416), cv::Scalar(0, 0, 0), true, false);
+            net.setInput(blob);
+            std::vector<cv::Mat> outs;
+            net.forward(outs, net.getUnconnectedOutLayersNames());
+            float *data = (float*)outs[0].data;
+            for(int i = 0; i < outs[0].rows; ++i) {
+                float final_score = data[4] * data[5];
+                if(final_score >= 0.0075)
+                {
+                    weights.push_back(final_score);
+                    int cx = data[0] * img.cols;
+                    int cy = data[1] * img.rows;
+                    int width = data[2] * img.cols;
+                    int height = data[3] * img.rows;
+                    int left = cx - width / 2;
+                    int top = cy - height / 2;
+                    found.push_back(cv::Rect(left, top, width, height));
+                }
+                data += 85;
+            }
+
+            target = 0;
+            for(unsigned i = 0; i < weights.size(); i++) {
+                if(weights[i] > weights[target])
+                    target = i;
+            }
+
+            if(track && !weights.empty()) {
+                float yaw = target_x = found[target].x;
+                float pitch = target_y = found[target].y;
+
+                // Normalize the coordinates
+                yaw = 2 * (yaw - img.cols / 2) / img.cols;
+                pitch = 2 * (pitch - img.rows / 2) / img.rows;
+
+                robot_target(robot, pitch, yaw);
+            }
+        }
+
+        lock.unlock();
+
+        SDL_Delay(250);
+    }
+
+}
+
+static void captureFrameThread(SDL_Window* window, const char* fname) {
+
+    SDL_Delay(750);
+
+    av_register_all();
+    avcodec_register_all();
+    AVFormatContext* pFormatCtx = avformat_alloc_context();
+    
+    if (avformat_open_input(&pFormatCtx, fname, NULL, NULL) != 0) {
+        std::cerr << "Couldn't open stream\n";
+        return;
+    }
+    
+    if (avformat_find_stream_info(pFormatCtx, NULL) < 0) {
+        std::cerr << "Couldn't find stream information\n";
+        return;
+    }
+
+    int videoStream = -1;
+    for (unsigned int i = 0; i < pFormatCtx->nb_streams; i++) {
+        if (pFormatCtx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
+            videoStream = i;
+            break;
+        }
+    }
+
+    if (videoStream == -1) {
+        std::cerr << "Didn't find a video stream\n";
+        return;
+    }
+
+    AVCodecParameters* pCodecParameters = pFormatCtx->streams[videoStream]->codecpar;
+    AVCodec* pCodec = avcodec_find_decoder(pCodecParameters->codec_id);
+
+    if (pCodec == NULL) {
+        std::cerr << "Unsupported codec\n";
+        return;
+    }
+
+    AVCodecContext* pCodecCtx = avcodec_alloc_context3(pCodec);
+    pCodecCtx->pix_fmt = AV_PIX_FMT_GRAY8;
+    avcodec_parameters_to_context(pCodecCtx, pCodecParameters);
+
+    if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0) {
+        std::cerr << "Could not open codec\n";
+        return;
+    }
+
+    AVFrame* pFrame = av_frame_alloc();
+    AVFrame* pFrameRGB = av_frame_alloc();
+    
+    int numBytes = av_image_get_buffer_size(AV_PIX_FMT_RGB24, pCodecCtx->width, pCodecCtx->height, 1);
+    uint8_t* buffer = (uint8_t*)av_malloc(numBytes * sizeof(uint8_t));
+    av_image_fill_arrays(pFrameRGB->data, pFrameRGB->linesize, buffer, AV_PIX_FMT_BGR24, pCodecCtx->width, pCodecCtx->height, 1);
+
+    SwsContext* sws_ctx = sws_getContext(
+        pCodecCtx->width,
+        pCodecCtx->height,
+        pCodecCtx->pix_fmt,
+        pCodecCtx->width,
+        pCodecCtx->height,
+        AV_PIX_FMT_BGR24,
+        SWS_BILINEAR,
+        NULL,
+        NULL,
+        NULL);
+
+    SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, 0);
+    SDL_Texture* texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_BGR24, SDL_TEXTUREACCESS_STATIC, pCodecCtx->width, pCodecCtx->height);
+
+    while (!stop) {
+        AVPacket packet;
+        if(av_read_frame(pFormatCtx, &packet) < 0) {
+            std::cerr << "Error while reading a frame\n";
+            stop = true;
+            break;
+        }
+        
+        if (packet.stream_index == videoStream) {
+            int response = avcodec_send_packet(pCodecCtx, &packet);
+            if (response < 0) {
+                std::cerr << "Error while sending a packet to the decoder: " << response << '\n';
+                stop = true;
+                break;
+            }
+
+            while (response >= 0) {
+                response = avcodec_receive_frame(pCodecCtx, pFrame);
+                if (response == AVERROR(EAGAIN) || response == AVERROR_EOF) {
+                    break;
+                } else if (response < 0) {
+                    std::cerr << "Error while receiving a frame from the decoder: " << response << '\n';
+                    stop = true;
+                    break;
+                }
+
+                if (response >= 0) {
+                    sws_scale(sws_ctx, (uint8_t const* const*)pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);
+
+                    std::unique_lock<std::mutex> lock(mtx);
+
+                    img = cv::Mat(pCodecCtx->height, pCodecCtx->width, CV_8UC3, pFrameRGB->data[0], pFrameRGB->linesize[0]);
+                    for (unsigned i = 0; i < found.size(); i++) {
+                        rectangle(img, found[i], cv::Scalar(255 - weights[i] * 255, 0, weights[i] * 255), 3);
+                    }
+
+
+                    SDL_UpdateTexture(texture, NULL, img.data, img.cols * 3);
+                    SDL_RenderDrawLine(renderer, 1280 / 2, 720 / 2, target_x, target_y);
+
+                    SDL_RenderClear(renderer);
+                    SDL_RenderCopy(renderer, texture, NULL, NULL);
+                    SDL_RenderPresent(renderer);
+
+                    lock.unlock();
+                }
+            }
+        }
+        av_packet_unref(&packet);
+
+    }
+
+    av_free(buffer);
+    av_frame_free(&pFrameRGB);
+    av_frame_free(&pFrame);
+    avcodec_close(pCodecCtx);
+    avformat_close_input(&pFormatCtx);
+
+    SDL_DestroyTexture(texture);
+    SDL_DestroyRenderer(renderer);
+}
+
+int main(int argc, char* argv[]) {
+    if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
+        fprintf(stderr, "%s", SDL_GetError());
+        return 1;
+    }
+    printf("Detected %d joysticks\n", SDL_NumJoysticks());
+    SDL_Joystick* joystick = NULL;
+    if(SDL_NumJoysticks() > 0) {
+        joystick = SDL_JoystickOpen(0);
+    }
+    SDL_Window* win = SDL_CreateWindow(
+		    "Robomaster",
+		    SDL_WINDOWPOS_UNDEFINED,
+		    SDL_WINDOWPOS_UNDEFINED,
+		    1280, 720,
+		    SDL_WINDOW_RESIZABLE );
+    if(!win) {
+        fprintf(stderr, "%s", SDL_GetError());
+        return 1;
+    }
+
+    Robot robot = robot_new();
+    robot_init(robot);
+    robot_stream(robot, true);
+
+    SDL_AddTimer(75, drive_timer_handler, robot);
+    SDL_AddTimer(1000, heartbeat_timer_handler, robot);
+
+    int streamcount = 0;
+    std::thread *captureThread = nullptr;
+    std::thread *processThread = nullptr;
+
+    target_x = 720 / 2;
+    target_y = 1280 / 2;
+
+    while(robot_work(robot)) {
+
+        int h = 720, w = 1280;
+
+        struct Fragment fragment;
+        while(robot_poll(robot, &fragment)) {
+            switch(fragment.type) {
+                case FRAGMENT_RECTANGLE:
+                case FRAGMENT_LINE:
+                case FRAGMENT_MARKER:
+                    printf("Rect(%f,%f,%f,%f)\n",
+                            fragment.rect.rect.x,
+                            fragment.rect.rect.y,
+                            fragment.rect.rect.w,
+                            fragment.rect.rect.h );
+                    break;
+                case FRAGMENT_MESSAGE:
+                    switch(fragment.message.header.cmd) {
+                        case GIMBAL_ACTION_PUSH_CMD:
+                            if(fragment.message.push.gimbalaction.state != 1)
+                                break;
+                            yaw_cur = fragment.message.push.gimbalaction.yaw;
+                            pitch_cur = fragment.message.push.gimbalaction.pitch;
+                            printf("Gimbal action %d\n", fragment.message.push.gimbalaction.id);
+                            printf("\tProgress %d\n", fragment.message.push.gimbalaction.progress);
+                            printf("\tYaw %d, Pitch %d\n", yaw_cur, pitch_cur);
+                            break;
+                        case GIMBAL_ROTATE_CMD:
+                            if(fragment.message.resp.gimbalrot.retcode) {
+                                printf("ERROR: Gimbal rotate message failure\n");
+                                break;
+                            }
+                            break;
+                        case STREAM_CTRL_CMD:
+                            if(fragment.message.resp.stream.retcode) {
+                                printf("ERROR: Stream not enabled\n");
+                                break;
+                            }
+                            printf("Stream enabled\n");
+                            if(++streamcount >= 2) {
+                                captureThread = new std::thread(captureFrameThread, win, "tcp://192.168.2.1:40921");
+                                processThread = new std::thread(processFrameThread, robot);
+                            }
+                            break;
+                        case VISION_DETECT_ENABLE_CMD:
+                            if(fragment.message.resp.enablevision.retcode) {
+                                printf("ERROR: Vision not enabled\n");
+                                break;
+                            }
+                            if(fragment.message.resp.enablevision.error) {
+                                printf("ERROR: Vision not enabled %d\n",
+                                    fragment.message.resp.enablevision.error);
+                                break;
+                            }
+                            printf("Vision enabled\n");
+                            break;
+                    }
+                    break;
+                default:
+                    printf("Unhandled fragment type\n");
+                    break;
+            }
+        }
+
+        SDL_Event event;
+        while(SDL_PollEvent(&event)) {
+            switch(event.type) {
+                case SDL_KEYUP:
+                case SDL_KEYDOWN:
+                    switch(event.key.keysym.scancode) {
+                        case SDL_SCANCODE_Q:
+                            z = event.type == SDL_KEYUP ? 0 : 0.25;
+                            break;
+                        case SDL_SCANCODE_E:
+                            z = event.type == SDL_KEYUP ? 0 : -0.25;
+                            break;
+                        case SDL_SCANCODE_LEFT:
+                        case SDL_SCANCODE_A:
+                            x = event.type == SDL_KEYUP ? 0 : 0.25;
+                            break;
+                        case SDL_SCANCODE_RIGHT:
+                        case SDL_SCANCODE_D:
+                            x = event.type == SDL_KEYUP ? 0 : -0.25;
+                            break;
+                        case SDL_SCANCODE_UP:
+                        case SDL_SCANCODE_W:
+                            y = event.type == SDL_KEYUP ? 0 : 0.25;
+                            break;
+                        case SDL_SCANCODE_DOWN:
+                        case SDL_SCANCODE_S:
+                            y = event.type == SDL_KEYUP ? 0 : -0.25;
+                            break;
+                        case SDL_SCANCODE_SPACE:
+                            robot_led(robot, colors[color].r, colors[color].g, colors[color].b);
+                            color = (color + 1) % 3;
+                            break;
+                        case SDL_SCANCODE_RETURN:
+                            robot_blast(robot);
+                            break;
+                        case SDL_SCANCODE_T:
+                            track = true;
+                            break;
+                        default: break;
+		            }
+                    break;
+                case SDL_MOUSEBUTTONDOWN:
+                {
+                    // Get window coordinates
+                    SDL_GetMouseState(&target_x, &target_y);
+
+                    float yaw = target_x;
+                    float pitch = target_y;
+
+                    // Normalize the coordinates
+                    yaw = 2 * (yaw - w / 2) / w;
+                    pitch = 2 * (pitch - h / 2) / h;
+
+                    robot_target(robot, pitch, yaw);
+
+                    break;
+                }
+                case SDL_WINDOWEVENT:
+                    if(event.window.event != SDL_WINDOWEVENT_CLOSE) break;
+                case SDL_QUIT:
+                    robot_stop(robot);
+                    stop = true;
+                default: break;
+	        }
+	    }
+    }
+
+    if(captureThread != nullptr) {
+        captureThread->join();
+        delete captureThread;
+    }
+    if(processThread != nullptr) {
+        processThread->join();
+        delete processThread;
+    }
+    SDL_JoystickClose(joystick);
+    SDL_Quit();
+    return 0;
+}
+

src/stream.cpp

@@ -0,0 +1,233 @@
+#include <iostream>
+#include <thread>
+#include <mutex>
+#include <cmath>
+#include <opencv2/opencv.hpp>
+#include <opencv2/dnn/dnn.hpp>
+#include <SDL2/SDL.h>
+
+extern "C" {
+#include <libavcodec/avcodec.h>
+#include <libavformat/avformat.h>
+#include <libswscale/swscale.h>
+#include <libavutil/imgutils.h>
+}
+
+std::mutex mtx;
+cv::Mat img;
+std::vector<cv::Rect> found;
+std::vector<double> weights;
+unsigned target;
+
+bool stop = false;
+
+static void processFrameThread() {
+    cv::dnn::Net net = cv::dnn::readNet("yolov3-tiny.weights", "yolov3-tiny.cfg");
+
+    while(!stop) {
+        std::unique_lock<std::mutex> lock(mtx);
+
+        if(!img.empty()) {
+            found.clear();
+            weights.clear();
+            cv::Mat blob = cv::dnn::blobFromImage(img, 1/255.0, cv::Size(416, 416), cv::Scalar(0, 0, 0), true, false);
+            net.setInput(blob);
+            std::vector<cv::Mat> outs;
+            net.forward(outs, net.getUnconnectedOutLayersNames());
+            float *data = (float*)outs[0].data;
+            for(int i = 0; i < outs[0].rows; ++i) {
+                float final_score = data[4] * data[5];
+                if(final_score >= 0.0075)
+                {
+                    weights.push_back(final_score);
+                    int cx = data[0] * img.cols;
+                    int cy = data[1] * img.rows;
+                    int width = data[2] * img.cols;
+                    int height = data[3] * img.rows;
+                    int left = cx - width / 2;
+                    int top = cy - height / 2;
+                    found.push_back(cv::Rect(left, top, width, height));
+                }
+                data += 85;
+            }
+        }
+
+        lock.unlock();
+
+        SDL_Delay(250);
+    }
+
+}
+
+static void captureFrameThread(SDL_Window* window, const char* fname) {
+
+    av_register_all();
+    avcodec_register_all();
+    AVFormatContext* pFormatCtx = avformat_alloc_context();
+    
+    if (avformat_open_input(&pFormatCtx, fname, NULL, NULL) != 0) {
+        std::cerr << "Couldn't open stream\n";
+        return;
+    }
+    
+    if (avformat_find_stream_info(pFormatCtx, NULL) < 0) {
+        std::cerr << "Couldn't find stream information\n";
+        return;
+    }
+
+    int videoStream = -1;
+    for (unsigned int i = 0; i < pFormatCtx->nb_streams; i++) {
+        if (pFormatCtx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
+            videoStream = i;
+            break;
+        }
+    }
+
+    if (videoStream == -1) {
+        std::cerr << "Didn't find a video stream\n";
+        return;
+    }
+
+    AVCodecParameters* pCodecParameters = pFormatCtx->streams[videoStream]->codecpar;
+    AVCodec* pCodec = avcodec_find_decoder(pCodecParameters->codec_id);
+
+    if (pCodec == NULL) {
+        std::cerr << "Unsupported codec\n";
+        return;
+    }
+
+    AVCodecContext* pCodecCtx = avcodec_alloc_context3(pCodec);
+    pCodecCtx->pix_fmt = AV_PIX_FMT_GRAY8;
+    avcodec_parameters_to_context(pCodecCtx, pCodecParameters);
+
+    if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0) {
+        std::cerr << "Could not open codec\n";
+        return;
+    }
+
+    AVFrame* pFrame = av_frame_alloc();
+    AVFrame* pFrameRGB = av_frame_alloc();
+    
+    int numBytes = av_image_get_buffer_size(AV_PIX_FMT_RGB24, pCodecCtx->width, pCodecCtx->height, 1);
+    uint8_t* buffer = (uint8_t*)av_malloc(numBytes * sizeof(uint8_t));
+    av_image_fill_arrays(pFrameRGB->data, pFrameRGB->linesize, buffer, AV_PIX_FMT_BGR24, pCodecCtx->width, pCodecCtx->height, 1);
+
+    SwsContext* sws_ctx = sws_getContext(
+        pCodecCtx->width,
+        pCodecCtx->height,
+        pCodecCtx->pix_fmt,
+        pCodecCtx->width,
+        pCodecCtx->height,
+        AV_PIX_FMT_BGR24,
+        SWS_BILINEAR,
+        NULL,
+        NULL,
+        NULL);
+
+    //AVRational time_base = pFormatCtx->streams[videoStream]->time_base;
+    //AVRational frame_rate = av_guess_frame_rate(pFormatCtx, pFormatCtx->streams[videoStream], NULL);
+    //uint32_t delay = (av_rescale_q(1, av_inv_q(frame_rate), time_base) / AV_TIME_BASE) * 1000;
+    //printf("delay: %u\n", delay);
+
+    SDL_SetWindowSize(window, pCodecCtx->width, pCodecCtx->height);
+    SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, 0);
+    SDL_Texture* texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_BGR24, SDL_TEXTUREACCESS_STATIC, pCodecCtx->width, pCodecCtx->height);
+
+    while (!stop) {
+        AVPacket packet;
+        if(av_read_frame(pFormatCtx, &packet) < 0) {
+            stop = true;
+            break;
+        }
+        
+        if (packet.stream_index == videoStream) {
+            int response = avcodec_send_packet(pCodecCtx, &packet);
+            if (response < 0) {
+                std::cerr << "Error while sending a packet to the decoder: " << response << '\n';
+                return;
+            }
+
+            while (response >= 0) {
+                response = avcodec_receive_frame(pCodecCtx, pFrame);
+                if (response == AVERROR(EAGAIN) || response == AVERROR_EOF) {
+                    break;
+                } else if (response < 0) {
+                    std::cerr << "Error while receiving a frame from the decoder: " << response << '\n';
+                    return;
+                }
+
+                if (response >= 0) {
+                    sws_scale(sws_ctx, (uint8_t const* const*)pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);
+
+                    std::unique_lock<std::mutex> lock(mtx);
+
+                    img = cv::Mat(pCodecCtx->height, pCodecCtx->width, CV_8UC3, pFrameRGB->data[0], pFrameRGB->linesize[0]);
+
+                    for (unsigned i = 0; i < found.size(); i++) {
+                        rectangle(img, found[i], cv::Scalar(255 - weights[i] * 255, 0, weights[i] * 255), 3);
+                    }
+
+                    lock.unlock();
+
+                    {
+                        SDL_UpdateTexture(texture, NULL, img.data, img.cols * 3);
+                        SDL_RenderClear(renderer);
+                        SDL_RenderCopy(renderer, texture, NULL, NULL);
+                        SDL_RenderPresent(renderer);
+                    }
+                }
+            }
+        }
+        av_packet_unref(&packet);
+
+        SDL_Event event;
+        while(SDL_PollEvent(&event)) {
+            switch(event.type) {
+                case SDL_QUIT:
+                    stop = true;
+                default: break;
+            }
+        }
+
+        SDL_Delay(33);
+
+    }
+
+    av_free(buffer);
+    av_frame_free(&pFrameRGB);
+    av_frame_free(&pFrame);
+    avcodec_close(pCodecCtx);
+    avformat_close_input(&pFormatCtx);
+
+    SDL_DestroyTexture(texture);
+    SDL_DestroyRenderer(renderer);
+}
+
+int main(int argc, char* argv[]) {
+    if(SDL_Init(SDL_INIT_VIDEO) < 0) {
+        fprintf(stderr, "%s", SDL_GetError());
+        return 1;
+    }
+
+    SDL_Window* win = SDL_CreateWindow(
+		    "Robomaster",
+		    SDL_WINDOWPOS_UNDEFINED,
+		    SDL_WINDOWPOS_UNDEFINED,
+		    800, 300,
+		    SDL_WINDOW_RESIZABLE );
+    if(!win) {
+        fprintf(stderr, "%s", SDL_GetError());
+        return 1;
+    }
+
+    std::thread captureThread(captureFrameThread, win, argv[1]);
+    std::thread processThread(processFrameThread);
+
+    captureThread.join();
+    processThread.join();
+
+    SDL_Quit();
+
+    return 0;
+}
+