https://blog.csdn.net/chenshiming1995/article/details/106546455
雙目相機標定+去畸變+獲得視差+深度
一共需要解決幾個問題:
棋格板或者圓點板,代碼有細微差別
怎樣對比標定結果: 觀察像素誤差
需不需要棋盤格子的尺寸:內參不需要,只有計算雙目間的外參R和T時,T與棋盤格大小相關,成正比關系。另外T[0]代表基線長度
代碼的正確性:沒有錯誤,已檢查過,當然一些是復制別人的工作
導入你自己的標定圖片需要更改:
角點個數(目前是7*7)
文件夾名稱(顯然)
世界坐標系的圓心點距離(目前是15mm)
確定是棋盤格還是圓心標定板(目前用的圓點板)
一共有三段代碼,建議在ipython notebook下運行
5. 第一段:雙目標定
6. 第二段:配置內參參數
7. 第三段:去畸變+獲得視差+深度
import cv2 import matplotlib.pyplot as plt # plt 用於顯示圖片 import matplotlib.image as mpimg # mpimg 用於讀取圖片 import sys import numpy as np import glob class shuangmu: def __init__(self): self.m1 = 0 self.m2 = 0 self.d1 = 0 self.d2 = 0 self.R = 0 self.T = 0 stereo = shuangmu() class StereoCalibration(object): def __init__(self): self.imagesL = self.read_images('camL') self.imagesR = self.read_images('camR') def read_images(self , cal_path): filepath = glob.glob(cal_path + '/*.bmp') filepath.sort() return filepath #標定圖像 def calibration_photo(self): #設置要標定的角點個數 x_nums = 7 #x方向上的角點個數 y_nums = 7 # 設置(生成)標定圖在世界坐標中的坐標 world_point = np.zeros((x_nums * y_nums,3),np.float32) #生成x_nums*y_nums個坐標,每個坐標包含x,y,z三個元素 world_point[:,:2] = np.mgrid[:x_nums,:y_nums].T.reshape(-1, 2) #mgrid[]生成包含兩個二維矩陣的矩陣,每個矩陣都有x_nums列,y_nums行 #.T矩陣的轉置 #reshape()重新規划矩陣,但不改變矩陣元素 #保存角點坐標 world_position = [] image_positionl = [] image_positionr = [] #設置角點查找限制 criteria = (cv2.TERM_CRITERIA_EPS + cv2.TERM_CRITERIA_MAX_ITER,30,0.001) #獲取所有標定圖 for ii in range(20): image_path_l = self.imagesL[ii] image_path_r = self.imagesR[ii] image_l = cv2.imread(image_path_l) image_r = cv2.imread(image_path_r) gray_l = cv2.cvtColor(image_l,cv2.COLOR_RGB2GRAY) gray_r = cv2.cvtColor(image_r,cv2.COLOR_RGB2GRAY) #查找角點 # ok,corners = cv2.findChessboardCorners(gray,(x_nums,y_nums),None) # ok1,cornersl = cv2.findChessboardCorners(gray_l,(x_nums,y_nums),None) # ok2,cornersr = cv2.findChessboardCorners(gray_r,(x_nums,y_nums),None) ok1,cornersl = cv2.findCirclesGrid(gray_l,(x_nums,y_nums),None) ok2,cornersr = cv2.findCirclesGrid(gray_r,(x_nums,y_nums),None) self.world = world_point print(ok1&ok2) if ok1&ok2: #把每一幅圖像的世界坐標放到world_position中 center_spacing = 15 ## 圓心的位置距離,這一個其實不重要 world_position.append(world_point*center_spacing) #獲取更精確的角點位置 exact_cornersl = cv2.cornerSubPix(gray_l,cornersl,(11,11),(-1,-1),criteria) exact_cornersr = cv2.cornerSubPix(gray_r,cornersr,(11,11),(-1,-1),criteria) #把獲取的角點坐標放到image_position中 image_positionl.append(exact_cornersl) image_positionr.append(exact_cornersr) #可視化角點 # image = cv2.drawChessboardCorners(image,(x_nums,y_nums),exact_corners,ok) # cv2.imshow('image_corner',image) # cv2.waitKey(0) #計算內參數 image_shape = gray_l.shape[::-1] retl, mtxl, distl, rvecsl, tvecsl = cv2.calibrateCamera(world_position, image_positionl, image_shape , None,None) retr, mtxr, distr, rvecsr, tvecsr = cv2.calibrateCamera(world_position, image_positionr, image_shape , None,None) print('ml = ',mtxl) print('mr = ',mtxr) print('dl = ' , distl) print('dr = ' , distr) stereo.m1 = mtxl stereo.m2 = mtxr stereo.d1 = distl stereo.d2 = distr #計算誤差 self.cal_error(world_position , image_positionl , mtxl , distl , rvecsl , tvecsl) self.cal_error(world_position , image_positionr , mtxr, distr , rvecsr , tvecsr) ##雙目標定 self.stereo_calibrate( world_position ,image_positionl , image_positionr , mtxl, distl, mtxr, distr, image_shape) def cal_error(self , world_position , image_position , mtx , dist , rvecs , tvecs): #計算偏差 mean_error = 0 for i in range(len(world_position)): image_position2, _ = cv2.projectPoints(world_position[i], rvecs[i], tvecs[i], mtx, dist) error = cv2.norm(image_position[i], image_position2, cv2.NORM_L2) / len(image_position2) mean_error += error print("total error: ", mean_error / len(image_position)) def stereo_calibrate( self , objpoints ,imgpoints_l , imgpoints_r , M1, d1, M2, d2, dims): flags = 0 flags |= cv2.CALIB_FIX_INTRINSIC flags |= cv2.CALIB_USE_INTRINSIC_GUESS flags |= cv2.CALIB_FIX_FOCAL_LENGTH flags |= cv2.CALIB_ZERO_TANGENT_DIST stereocalib_criteria = (cv2.TERM_CRITERIA_MAX_ITER +cv2.TERM_CRITERIA_EPS, 100, 1e-5) ret, M1, d1, M2, d2, R, T, E, F = cv2.stereoCalibrate( objpoints, imgpoints_l, imgpoints_r, M1, d1, M2, d2, dims, criteria=stereocalib_criteria, flags=flags) print(R) print(T) stereo.R = R stereo.T = T if __name__ == '__main__': # calibration_photo() biaoding = StereoCalibration() biaoding.calibration_photo()
import numpy as np import cv2 #雙目相機參數 class stereoCameral(object): def __init__(self): #左相機內參數 self.cam_matrix_left = stereo.m1 #右相機內參數 self.cam_matrix_right = stereo.m2 #左右相機畸變系數:[k1, k2, p1, p2, k3] self.distortion_l = stereo.d1 self.distortion_r = stereo.d2 #旋轉矩陣 self.R = stereo.R #平移矩陣 self.T = stereo.T self.baseline = stereo.T[0]
import cv2 import numpy as np import matplotlib.pyplot as plt # plt 用於顯示圖片 import matplotlib.image as mpimg # mpimg 用於讀取圖片 # 預處理 def preprocess(img1, img2): # 彩色圖->灰度圖 im1 = cv2.cvtColor(img1, cv2.COLOR_BGR2GRAY) im2 = cv2.cvtColor(img2, cv2.COLOR_BGR2GRAY) # 直方圖均衡 im1 = cv2.equalizeHist(im1) im2 = cv2.equalizeHist(im2) return im1, im2 # 消除畸變 def undistortion(image, camera_matrix, dist_coeff): undistortion_image = cv2.undistort(image, camera_matrix, dist_coeff) return undistortion_image # 獲取畸變校正和立體校正的映射變換矩陣、重投影矩陣 # @param:config是一個類,存儲着雙目標定的參數:config = stereoconfig.stereoCamera() def getRectifyTransform(height, width, config): # 讀取內參和外參 left_K = config.cam_matrix_left right_K = config.cam_matrix_right left_distortion = config.distortion_l right_distortion = config.distortion_r R = config.R T = config.T # 計算校正變換 height = int(height) width = int(width) R1, R2, P1, P2, Q, roi1, roi2 = cv2.stereoRectify(left_K, left_distortion, right_K, right_distortion, (width, height), R, T, alpha=-1) map1x, map1y = cv2.initUndistortRectifyMap(left_K, left_distortion, R1, P1, (width, height), cv2.CV_16SC2) map2x, map2y = cv2.initUndistortRectifyMap(right_K, right_distortion, R2, P2, (width, height), cv2.CV_16SC2) print(width,height) return map1x, map1y, map2x, map2y, Q # 畸變校正和立體校正 def rectifyImage(image1, image2, map1x, map1y, map2x, map2y): rectifyed_img1 = cv2.remap(image1, map1x, map1y, cv2.INTER_LINEAR) rectifyed_img2 = cv2.remap(image2, map2x, map2y, cv2.INTER_LINEAR) return rectifyed_img1, rectifyed_img2 # 立體校正檢驗----畫線 def draw_line1(image1, image2): # 建立輸出圖像 height = max(image1.shape[0], image2.shape[0]) width = image1.shape[1] + image2.shape[1] output = np.zeros((height, width,3), dtype=np.uint8) output[0:image1.shape[0], 0:image1.shape[1]] = image1 output[0:image2.shape[0], image1.shape[1]:] = image2 for k in range(15): cv2.line(output, (0, 50 * (k + 1)), (2 * width, 50 * (k + 1)), (0, 255, 0), thickness=2, lineType=cv2.LINE_AA) # 直線間隔:100 return output # 立體校正檢驗----畫線 def draw_line2(image1, image2): # 建立輸出圖像 height = max(image1.shape[0], image2.shape[0]) width = image1.shape[1] + image2.shape[1] output = np.zeros((height, width), dtype=np.uint8) output[0:image1.shape[0], 0:image1.shape[1]] = image1 output[0:image2.shape[0], image1.shape[1]:] = image2 for k in range(15): cv2.line(output, (0, 50 * (k + 1)), (2 * width, 50 * (k + 1)), (0, 255, 0), thickness=2, lineType=cv2.LINE_AA) # 直線間隔:100 return output # 視差計算 def disparity_SGBM(left_image, right_image, down_scale=False): # SGBM匹配參數設置 if left_image.ndim == 2: img_channels = 1 else: img_channels = 3 blockSize = 3 param = {'minDisparity': 0, 'numDisparities': 128, 'blockSize': blockSize, 'P1': 8 * img_channels * blockSize ** 2, 'P2': 32 * img_channels * blockSize ** 2, 'disp12MaxDiff': 1, 'preFilterCap': 63, 'uniquenessRatio': 15, 'speckleWindowSize': 100, 'speckleRange': 1, 'mode': cv2.STEREO_SGBM_MODE_SGBM_3WAY } # 構建SGBM對象 sgbm = cv2.StereoSGBM_create(**param) # 計算視差圖 size = (left_image.shape[1], left_image.shape[0]) if down_scale == False: disparity_left = sgbm.compute(left_image, right_image) disparity_right = sgbm.compute(right_image, left_image) else: left_image_down = cv2.pyrDown(left_image) right_image_down = cv2.pyrDown(right_image) factor = size[0] / left_image_down.shape[1] disparity_left_half = sgbm.compute(left_image_down, right_image_down) disparity_right_half = sgbm.compute(right_image_down, left_image_down) disparity_left = cv2.resize(disparity_left_half, size, interpolation=cv2.INTER_AREA) disparity_right = cv2.resize(disparity_right_half, size, interpolation=cv2.INTER_AREA) disparity_left *= factor disparity_right *= factor return disparity_left, disparity_right if __name__ == '__main__': imgL = cv2.imread("camL/L10.bmp") imgR = cv2.imread("camR/R10.bmp") # imgL , imgR = preprocess(imgL ,imgR ) height, width = imgL.shape[0:2] config = stereoCameral() # 讀取相機內參和外參 # 去畸變 imgL = undistortion(imgL ,config.cam_matrix_left , config.distortion_l ) imgR = undistortion(imgR ,config.cam_matrix_right, config.distortion_r ) # 去畸變和幾何極線對齊 map1x, map1y, map2x, map2y, Q = getRectifyTransform(height, width, config) iml_rectified, imr_rectified = rectifyImage(imgL, imgR, map1x, map1y, map2x, map2y) linepic = draw_line1(iml_rectified , imr_rectified) plt.imshow(linepic) # 計算視差 lookdispL,lookdispR = disparity_SGBM(iml_rectified , imr_rectified ) linepic2 = draw_line2(lookdispL,lookdispR) plt.imshow(linepic2) # points_3d = cv2.reprojectImageTo3D(lookdispL, Q)
相機1參數-左 內參stereoParams_v2.CameraParameters1.IntrinsicMatrix 1437.23707719718 0 0 -0.163005525961248 1436.86470419033 0 966.786371484151 540.390795809632 1 畸變 stereoParams_v2.CameraParameters1.RadialDistortion 0.0203815336602082 -0.0892188525805868 0.0905320816763131 stereoParams_v2.CameraParameters1.TangentialDistortion 0.00102781329079596 -0.000854815661759533 相機2參數-右 內參stereoParams_v2.CameraParameters1.IntrinsicMatrix 1437.23707719618 0 0 -0.163005527144222 1436.86470418913 0 966.786371477582 540.390795813682 1 畸變 stereoParams_v2.CameraParameters1.RadialDistortion 0.0203815336535712 -0.0892188525415953 0.0905320816167176 stereoParams_v2.CameraParameters1.TangentialDistortion 0.00102781329168718 -0.000854815663150387 相機2到相機1的變換 旋轉stereoParams_v2.RotationOfCamera2 1 0 0 0 1 0 0 0 1 位移stereoParams_v2.TranslationOfCamera2 6.38975788941902e-10 -9.79644888346105e-10 -1.09875374991737e-09
使用matlab可視化深度
https://blog.csdn.net/a6333230/article/details/88245102