AirSim 利用pygame绘制窗口并获取无人机FPV实时图像呈现

利用pygame绘制窗口并获取无人机FPV实时图像呈现的代码如下：

import sys
import time
import airsim
import pygame
import cv2
import numpy as np

# >------>>>  pygame settings   <<<------< #
pygame.init()

# 创建 pygame 窗口
screen = pygame.display.set_mode((800, 144))
pygame.display.set_caption('screen')
screen.fill((0, 0, 0))

# >------>>>  AirSim settings   <<<------< #
# 这里改为你要控制的无人机名称(settings文件里面设置的)
vehicle_name = "Drone"
AirSim_client = airsim.MultirotorClient()
AirSim_client.confirmConnection()
AirSim_client.enableApiControl(True, vehicle_name=vehicle_name)
AirSim_client.armDisarm(True, vehicle_name=vehicle_name)
AirSim_client.takeoffAsync(vehicle_name=vehicle_name).join()

# 图像类型字典
image_types = {
    "scene": airsim.ImageType.Scene,
    "depth": airsim.ImageType.DepthVis,
    "seg": airsim.ImageType.Segmentation,
    "normals": airsim.ImageType.SurfaceNormals,
    "segmentation": airsim.ImageType.Segmentation,
    "disparity": airsim.ImageType.DisparityNormalized,
    "Infrared": airsim.ImageType.Infrared
}

# 基础的控制速度(m/s)
vehicle_velocity = 2.0
# 设置临时加速比例
speedup_ratio = 10.0
# 用来设置临时加速
speedup_flag = False

# 基础的偏航速率
vehicle_yaw_rate = 5.0

# 主循环
while True:
    yaw_rate = 0.0
    velocity_x = 0.0
    velocity_y = 0.0
    velocity_z = 0.0

    # 小暂停，避免过度占用CPU
    time.sleep(0.02)

    # 处理pygame事件
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()

    # 获取键盘输入状态
    scan_wrapper = pygame.key.get_pressed()

    # 按下空格键加速10倍
    if scan_wrapper[pygame.K_SPACE]:
        scale_ratio = speedup_ratio
    else:
        scale_ratio = 1.0

    # 根据 'A' 和 'D' 按键来设置偏航速率变量
    if scan_wrapper[pygame.K_a] or scan_wrapper[pygame.K_d]:
        yaw_rate = (scan_wrapper[pygame.K_d] - scan_wrapper[pygame.K_a]) * scale_ratio * vehicle_yaw_rate

    # 根据 'UP' 和 'DOWN' 按键来设置pitch轴速度变量(NED坐标系，x为机头向前)
    if scan_wrapper[pygame.K_UP] or scan_wrapper[pygame.K_DOWN]:
        velocity_x = (scan_wrapper[pygame.K_UP] - scan_wrapper[pygame.K_DOWN]) * scale_ratio

    # 根据 'LEFT' 和 'RIGHT' 按键来设置roll轴速度变量(NED坐标系，y为正右方)
    if scan_wrapper[pygame.K_LEFT] or scan_wrapper[pygame.K_RIGHT]:
        velocity_y = -(scan_wrapper[pygame.K_LEFT] - scan_wrapper[pygame.K_RIGHT]) * scale_ratio

    # 根据 'W' 和 'S' 按键来设置z轴速度变量(NED坐标系，z轴向上为负)
    if scan_wrapper[pygame.K_w] or scan_wrapper[pygame.K_s]:
        velocity_z = -(scan_wrapper[pygame.K_w] - scan_wrapper[pygame.K_s]) * scale_ratio

    # 设置速度控制以及设置偏航控制
    AirSim_client.moveByVelocityBodyFrameAsync(vx=velocity_x, vy=velocity_y, vz=velocity_z, duration=1,
                                               yaw_mode=airsim.YawMode(True, yaw_or_rate=yaw_rate), vehicle_name=vehicle_name)

    # 获取场景图像
    temp_image1 = AirSim_client.simGetImage('0', image_types["scene"], vehicle_name=vehicle_name)
    image1 = cv2.imdecode(airsim.string_to_uint8_array(temp_image1), cv2.IMREAD_COLOR)
    cv2.imwrite('screen/visual1.png', image1)

    # 显示场景图像
    screen_image1 = pygame.image.load("screen/visual1.png")
    screen.blit(screen_image1, (0, 0))
    pygame.display.flip()

    # 获取红外图像
    temp_image2 = AirSim_client.simGetImage('0', image_types["Infrared"], vehicle_name=vehicle_name)
    image2 = cv2.imdecode(airsim.string_to_uint8_array(temp_image2), cv2.IMREAD_COLOR)
    cv2.imwrite('screen/visual2.png', image2)

    # 显示红外图像
    screen_image2 = pygame.image.load("screen/visual2.png")
    screen.blit(screen_image2, (272, 0))
    pygame.display.flip()

    # 获取分割图像
    temp_image3 = AirSim_client.simGetImage('0', image_types["segmentation"], vehicle_name=vehicle_name)
    image3 = cv2.imdecode(airsim.string_to_uint8_array(temp_image3), cv2.IMREAD_COLOR)
    cv2.imwrite('screen/visual3.png', image3)

    # 显示分割图像
    screen_image3 = pygame.image.load("screen/visual3.png")
    screen.blit(screen_image3, (544, 0))
    pygame.display.flip()

    # 如果按下 ESC 键退出程序
    if scan_wrapper[pygame.K_ESCAPE]:
        pygame.quit()
        sys.exit()

前面的内容和pygame使用键盘控制无人机一致，大家可以查看之前的博客AirSim 使用Pygame鼠标键盘控制无人机-CSDN博客

主要不同点在这一块，即图像的获取与显示。

# 获取场景图像
    temp_image1 = AirSim_client.simGetImage('0', image_types["scene"], vehicle_name=vehicle_name)
    image1 = cv2.imdecode(airsim.string_to_uint8_array(temp_image1), cv2.IMREAD_COLOR)
    cv2.imwrite('screen/visual1.png', image1)

    # 显示场景图像
    screen_image1 = pygame.image.load("screen/visual1.png")
    screen.blit(screen_image1, (0, 0))
    pygame.display.flip()

    # 获取红外图像
    temp_image2 = AirSim_client.simGetImage('0', image_types["Infrared"], vehicle_name=vehicle_name)
    image2 = cv2.imdecode(airsim.string_to_uint8_array(temp_image2), cv2.IMREAD_COLOR)
    cv2.imwrite('screen/visual2.png', image2)

    # 显示红外图像
    screen_image2 = pygame.image.load("screen/visual2.png")
    screen.blit(screen_image2, (272, 0))
    pygame.display.flip()

    # 获取分割图像
    temp_image3 = AirSim_client.simGetImage('0', image_types["segmentation"], vehicle_name=vehicle_name)
    image3 = cv2.imdecode(airsim.string_to_uint8_array(temp_image3), cv2.IMREAD_COLOR)
    cv2.imwrite('screen/visual3.png', image3)

    # 显示分割图像
    screen_image3 = pygame.image.load("screen/visual3.png")
    screen.blit(screen_image3, (544, 0))
    pygame.display.flip()

我们通过键盘来移动无人机，不断的用无人机的前摄像头采集图像，再不断的显示。

采集图像与显示我们以场景图为例子：

# 获取场景图像
    temp_image1 = AirSim_client.simGetImage('0', image_types["scene"], vehicle_name=vehicle_name)
    image1 = cv2.imdecode(airsim.string_to_uint8_array(temp_image1), cv2.IMREAD_COLOR)
    cv2.imwrite('screen/visual1.png', image1)

    # 显示场景图像
    screen_image1 = pygame.image.load("screen/visual1.png")
    screen.blit(screen_image1, (0, 0))
    pygame.display.flip()

首先调用客户端AirSim_client的成员函数simGetImage来采集图片

temp_image1 = AirSim_client.simGetImage('0', image_types["scene"], vehicle_name=vehicle_name)

传入参数第一个为相机名称，0为前相机

第二个参数是采集图像的类别，我们传入我们之前图像类型字典中的scene的值，即采集airsim.ImageType.Scene类型图像。

第三个参数是无人机的名称。

然后调用cv2的imdecode方法，

image1 = cv2.imdecode(airsim.string_to_uint8_array(temp_image1), cv2.IMREAD_COLOR)

我们之前采集到的是字节流的数据，airsim.string_to_uint8_array(temp_image1) 将从 AirSim 获取的字节流（temp_image1）转换为 NumPy 数组（3通道的图像数组），cv2.IMREAD_COLOR 表示以彩色方式读取图像。

cv2.imwrite('screen/visual1.png', image1)

然后将图像保存到文件中，传入保存路径和三维图像数组。

screen_image1 = pygame.image.load("screen/visual1.png")

然后调用pygame的image.load()方法，加载图像文件，传入我们之前保存的图像路径。

之后显示图像

screen.blit(screen_image1, (0, 0))
pygame.display.flip()

screen.blit(screen_image1, (0, 0)) 将图像 screen_image1 绘制到 pygame 窗口上。(0, 0) 是绘制图像的左上角位置，表示图像会被绘制在窗口的最左上角。

pygame.display.flip() 更新显示的窗口，将图像显示在屏幕上。