''' Prepare KITTI data for 3D object detection. Author: Charles R. Qi Date: September 2017 Modified by Zhixin Wang ''' import argparse import os import pickle import sys import cv2 import numpy as np from PIL import Image BASE_DIR = os.path.dirname(os.path.abspath(__file__)) ROOT_DIR = os.path.dirname(BASE_DIR) sys.path.append(BASE_DIR) sys.path.append(ROOT_DIR) import kitti_util as utils from kitti_object import kitti_object from draw_util import get_lidar_in_image_fov from ops.pybind11.rbbox_iou import bbox_overlaps_2d def in_hull(p, hull): from scipy.spatial import Delaunay if not isinstance(hull, Delaunay): hull = Delaunay(hull) return hull.find_simplex(p) >= 0 def extract_pc_in_box3d(pc, box3d): ''' pc: (N,3), box3d: (8,3) ''' box3d_roi_inds = in_hull(pc[:, 0:3], box3d) return pc[box3d_roi_inds, :], box3d_roi_inds def extract_pc_in_box2d(pc, box2d): ''' pc: (N,2), box2d: (xmin,ymin,xmax,ymax) ''' box2d_corners = np.zeros((4, 2)) box2d_corners[0, :] = [box2d[0], box2d[1]] box2d_corners[1, :] = [box2d[2], box2d[1]] box2d_corners[2, :] = [box2d[2], box2d[3]] box2d_corners[3, :] = [box2d[0], box2d[3]] box2d_roi_inds = in_hull(pc[:, 0:2], box2d_corners) return pc[box2d_roi_inds, :], box2d_roi_inds def random_shift_box2d(box2d, img_height, img_width, shift_ratio=0.1): ''' Randomly shift box center, randomly scale width and height ''' r = shift_ratio xmin, ymin, xmax, ymax = box2d h = ymax - ymin w = xmax - xmin cx = (xmin + xmax) / 2.0 cy = (ymin + ymax) / 2.0 assert xmin < xmax and ymin < ymax while True: cx2 = cx + w * r * (np.random.random() * 2 - 1) cy2 = cy + h * r * (np.random.random() * 2 - 1) h2 = h * (1 + np.random.random() * 2 * r - r) # 0.9 to 1.1 w2 = w * (1 + np.random.random() * 2 * r - r) # 0.9 to 1.1 new_box2d = np.array([cx2 - w2 / 2.0, cy2 - h2 / 2.0, cx2 + w2 / 2.0, cy2 + h2 / 2.0]) new_box2d[[0, 2]] = np.clip(new_box2d[[0, 2]], 0, img_width - 1) new_box2d[[1, 3]] = np.clip(new_box2d[[1, 3]], 0, img_height - 1) if new_box2d[0] < new_box2d[2] and new_box2d[1] < new_box2d[3]: return new_box2d def extract_boxes(objects, type_whitelist): boxes_2d = [] boxes_3d = [] filter_objects = [] for obj_idx in range(len(objects)): obj = objects[obj_idx] if obj.type not in type_whitelist: continue boxes_2d += [obj.box2d] boxes_3d += [np.array([obj.t[0], obj.t[1], obj.t[2], obj.l, obj.w, obj.h, obj.ry])] filter_objects += [obj] if len(boxes_3d) != 0: boxes_3d = np.stack(boxes_3d, 0) boxes_2d = np.stack(boxes_2d, 0) return filter_objects, boxes_2d, boxes_3d def extract_frustum_det_data(idx_filename, split, output_filename, det_filename, perturb_box2d=False, augmentX=1, type_whitelist=['Car']): dataset = kitti_object(os.path.join(ROOT_DIR, 'data/kitti'), split) data_idx_list = [int(line.rstrip()) for line in open(idx_filename)] det_id_list, det_type_list, det_box2d_list, det_prob_list = \ read_det_file(det_filename) all_boxes_2d = {} for i, det_idx in enumerate(det_id_list): if det_idx not in all_boxes_2d: all_boxes_2d[det_idx] = [] all_boxes_2d[det_idx] += [ { 'type': det_type_list[i], 'box2d': det_box2d_list[i], 'prob': det_prob_list[i] } ] id_list = [] # int number box2d_list = [] # [xmin,ymin,xmax,ymax] box3d_list = [] # (8,3) array in rect camera coord input_list = [] # channel number = 4, xyz,intensity in rect camera coord label_list = [] # 1 for roi object, 0 for clutter type_list = [] # string e.g. Car heading_list = [] # ry (along y-axis in rect camera coord) radius of # (cont.) clockwise angle from positive x axis in velo coord. box3d_size_list = [] # array of l,w,h frustum_angle_list = [] # angle of 2d box center from pos x-axis gt_box2d_list = [] calib_list = [] pos_cnt = 0 all_cnt = 0 thresh = 0.5 if 'Car' in type_whitelist else 0.25 for data_idx in data_idx_list: print('------------- ', data_idx) calib = dataset.get_calibration(data_idx) # 3 by 4 matrix gt_objects = dataset.get_label_objects(data_idx) gt_objects, gt_boxes_2d, gt_boxes_3d = extract_boxes(gt_objects, type_whitelist) if len(gt_objects) == 0: continue pc_velo = dataset.get_lidar(data_idx) pc_rect = np.zeros_like(pc_velo) pc_rect[:, 0:3] = calib.project_velo_to_rect(pc_velo[:, 0:3]) pc_rect[:, 3] = pc_velo[:, 3] img = dataset.get_image(data_idx) img_height, img_width, img_channel = img.shape _, pc_image_coord, img_fov_inds = get_lidar_in_image_fov(pc_velo[:, 0:3], calib, 0, 0, img_width, img_height, True) det_objects = all_boxes_2d.get(data_idx) if det_objects is None: continue for obj_idx in range(len(det_objects)): cur_obj = det_objects[obj_idx] if cur_obj['type'] not in type_whitelist: continue overlap = bbox_overlaps_2d(cur_obj['box2d'].reshape(-1, 4), gt_boxes_2d) overlap = overlap[0] max_overlap = overlap.max(0) max_idx = overlap.argmax(0) if max_overlap < thresh: continue assign_obj = gt_objects[max_idx] # 2D BOX: Get pts rect backprojected box2d = cur_obj['box2d'] for _ in range(augmentX): # Augment data by box2d perturbation if perturb_box2d: xmin, ymin, xmax, ymax = random_shift_box2d(box2d, img_height, img_width, 0.1) else: xmin, ymin, xmax, ymax = box2d box_fov_inds = (pc_image_coord[:, 0] < xmax) & \ (pc_image_coord[:, 0] >= xmin) & \ (pc_image_coord[:, 1] < ymax) & \ (pc_image_coord[:, 1] >= ymin) box_fov_inds = box_fov_inds & img_fov_inds pc_in_box_fov = pc_rect[box_fov_inds, :] pc_box_image_coord = pc_image_coord[box_fov_inds] # Get frustum angle (according to center pixel in 2D BOX) box2d_center = np.array([(xmin + xmax) / 2.0, (ymin + ymax) / 2.0]) uvdepth = np.zeros((1, 3)) uvdepth[0, 0:2] = box2d_center uvdepth[0, 2] = 20 # some random depth box2d_center_rect = calib.project_image_to_rect(uvdepth) frustum_angle = -1 * np.arctan2(box2d_center_rect[0, 2], box2d_center_rect[0, 0]) # 3D BOX: Get pts velo in 3d box obj = assign_obj box3d_pts_2d, box3d_pts_3d = utils.compute_box_3d(obj, calib.P) _, inds = extract_pc_in_box3d(pc_in_box_fov, box3d_pts_3d) label = np.zeros((pc_in_box_fov.shape[0])) label[inds] = 1 # Get 3D BOX heading heading_angle = obj.ry # Get 3D BOX size box3d_size = np.array([obj.l, obj.w, obj.h]) gt_box2d = obj.box2d # Reject too far away object or object without points if (gt_box2d[3] - gt_box2d[1]) < 25 or np.sum(label) == 0: # print(gt_box2d[3] - gt_box2d[1], np.sum(label)) continue id_list.append(data_idx) box2d_list.append(np.array([xmin, ymin, xmax, ymax])) box3d_list.append(box3d_pts_3d) input_list.append(pc_in_box_fov.astype(np.float32, copy=False)) label_list.append(label) type_list.append(obj.type) heading_list.append(heading_angle) box3d_size_list.append(box3d_size) frustum_angle_list.append(frustum_angle) gt_box2d_list.append(gt_box2d) calib_list.append(calib.calib_dict) # collect statistics pos_cnt += np.sum(label) all_cnt += pc_in_box_fov.shape[0] print('total_objects %d' % len(id_list)) print('Average pos ratio: %f' % (pos_cnt / float(all_cnt))) print('Average npoints: %f' % (float(all_cnt) / len(id_list))) with open(output_filename, 'wb') as fp: pickle.dump(id_list, fp, -1) pickle.dump(box2d_list, fp, -1) pickle.dump(box3d_list, fp, -1) pickle.dump(input_list, fp, -1) pickle.dump(label_list, fp, -1) pickle.dump(type_list, fp, -1) pickle.dump(heading_list, fp, -1) pickle.dump(box3d_size_list, fp, -1) pickle.dump(frustum_angle_list, fp, -1) pickle.dump(gt_box2d_list, fp, -1) pickle.dump(calib_list, fp, -1) print('save in {}'.format(output_filename)) def extract_frustum_data(idx_filename, split, output_filename, perturb_box2d=False, augmentX=1, type_whitelist=['Car']): ''' Extract point clouds and corresponding annotations in frustums defined generated from 2D bounding boxes Lidar points and 3d boxes are in *rect camera* coord system (as that in 3d box label files) Input: idx_filename: string, each line of the file is a sample ID split: string, either trianing or testing output_filename: string, the name for output .pickle file viz: bool, whether to visualize extracted data perturb_box2d: bool, whether to perturb the box2d (used for data augmentation in train set) augmentX: scalar, how many augmentations to have for each 2D box. type_whitelist: a list of strings, object types we are interested in. Output: None (will write a .pickle file to the disk) ''' dataset = kitti_object(os.path.join(ROOT_DIR, 'data/kitti'), split) data_idx_list = [int(line.rstrip()) for line in open(idx_filename)] id_list = [] # int number box2d_list = [] # [xmin,ymin,xmax,ymax] box3d_list = [] # (8,3) array in rect camera coord input_list = [] # channel number = 4, xyz,intensity in rect camera coord label_list = [] # 1 for roi object, 0 for clutter type_list = [] # string e.g. Car heading_list = [] # ry (along y-axis in rect camera coord) radius of # (cont.) clockwise angle from positive x axis in velo coord. box3d_size_list = [] # array of l,w,h frustum_angle_list = [] # angle of 2d box center from pos x-axis gt_box2d_list = [] calib_list = [] pos_cnt = 0 all_cnt = 0 for data_idx in data_idx_list: print('------------- ', data_idx) calib = dataset.get_calibration(data_idx) # 3 by 4 matrix objects = dataset.get_label_objects(data_idx) pc_velo = dataset.get_lidar(data_idx) pc_rect = np.zeros_like(pc_velo) pc_rect[:, 0:3] = calib.project_velo_to_rect(pc_velo[:, 0:3]) pc_rect[:, 3] = pc_velo[:, 3] img = dataset.get_image(data_idx) img_height, img_width, img_channel = img.shape _, pc_image_coord, img_fov_inds = get_lidar_in_image_fov(pc_velo[:, 0:3], calib, 0, 0, img_width, img_height, True) for obj_idx in range(len(objects)): if objects[obj_idx].type not in type_whitelist: continue # 2D BOX: Get pts rect backprojected box2d = objects[obj_idx].box2d for _ in range(augmentX): # Augment data by box2d perturbation if perturb_box2d: xmin, ymin, xmax, ymax = random_shift_box2d(box2d, img_height, img_width, 0.1) else: xmin, ymin, xmax, ymax = box2d box_fov_inds = (pc_image_coord[:, 0] < xmax) & \ (pc_image_coord[:, 0] >= xmin) & \ (pc_image_coord[:, 1] < ymax) & \ (pc_image_coord[:, 1] >= ymin) box_fov_inds = box_fov_inds & img_fov_inds pc_in_box_fov = pc_rect[box_fov_inds, :] pc_box_image_coord = pc_image_coord[box_fov_inds] # Get frustum angle (according to center pixel in 2D BOX) box2d_center = np.array([(xmin + xmax) / 2.0, (ymin + ymax) / 2.0]) uvdepth = np.zeros((1, 3)) uvdepth[0, 0:2] = box2d_center uvdepth[0, 2] = 20 # some random depth box2d_center_rect = calib.project_image_to_rect(uvdepth) frustum_angle = -1 * np.arctan2(box2d_center_rect[0, 2], box2d_center_rect[0, 0]) # 3D BOX: Get pts velo in 3d box obj = objects[obj_idx] box3d_pts_2d, box3d_pts_3d = utils.compute_box_3d(obj, calib.P) _, inds = extract_pc_in_box3d(pc_in_box_fov, box3d_pts_3d) label = np.zeros((pc_in_box_fov.shape[0])) label[inds] = 1 # Get 3D BOX heading heading_angle = obj.ry # Get 3D BOX size box3d_size = np.array([obj.l, obj.w, obj.h]) # Reject too far away object or object without points if (box2d[3] - box2d[1]) < 25 or np.sum(label) == 0: # print(box2d[3] - box2d[1], np.sum(label)) continue id_list.append(data_idx) box2d_list.append(np.array([xmin, ymin, xmax, ymax])) box3d_list.append(box3d_pts_3d) input_list.append(pc_in_box_fov.astype(np.float32, copy=False)) label_list.append(label) type_list.append(objects[obj_idx].type) heading_list.append(heading_angle) box3d_size_list.append(box3d_size) frustum_angle_list.append(frustum_angle) gt_box2d_list.append(box2d) calib_list.append(calib.calib_dict) # collect statistics pos_cnt += np.sum(label) all_cnt += pc_in_box_fov.shape[0] print('total_objects %d' % len(id_list)) print('Average pos ratio: %f' % (pos_cnt / float(all_cnt))) print('Average npoints: %f' % (float(all_cnt) / len(id_list))) with open(output_filename, 'wb') as fp: pickle.dump(id_list, fp, -1) pickle.dump(box2d_list, fp, -1) pickle.dump(box3d_list, fp, -1) pickle.dump(input_list, fp, -1) pickle.dump(label_list, fp, -1) pickle.dump(type_list, fp, -1) pickle.dump(heading_list, fp, -1) pickle.dump(box3d_size_list, fp, -1) pickle.dump(frustum_angle_list, fp, -1) pickle.dump(gt_box2d_list, fp, -1) pickle.dump(calib_list, fp, -1) print('save in {}'.format(output_filename)) def get_box3d_dim_statistics(idx_filename): ''' Collect and dump 3D bounding box statistics ''' dataset = kitti_object(os.path.join(ROOT_DIR, 'data/kitti')) dimension_list = [] type_list = [] ry_list = [] data_idx_list = [int(line.rstrip()) for line in open(idx_filename)] for data_idx in data_idx_list: print('------------- ', data_idx) calib = dataset.get_calibration(data_idx) # 3 by 4 matrix objects = dataset.get_label_objects(data_idx) for obj_idx in range(len(objects)): obj = objects[obj_idx] if obj.type == 'DontCare': continue dimension_list.append(np.array([obj.l, obj.w, obj.h])) type_list.append(obj.type) ry_list.append(obj.ry) with open('box3d_dimensions.pickle', 'wb') as fp: pickle.dump(type_list, fp) pickle.dump(dimension_list, fp) pickle.dump(ry_list, fp) def read_det_file(det_filename): ''' Parse lines in 2D detection output files ''' det_id2str = {1: 'Pedestrian', 2: 'Car', 3: 'Cyclist'} id_list = [] type_list = [] prob_list = [] box2d_list = [] for line in open(det_filename, 'r'): t = line.rstrip().split(" ") id_list.append(int(os.path.basename(t[0]).rstrip('.png'))) type_list.append(det_id2str[int(t[1])]) prob_list.append(float(t[2])) box2d_list.append(np.array([float(t[i]) for i in range(3, 7)])) return id_list, type_list, box2d_list, prob_list def read_det_pkl_file(det_filename): ''' Parse lines in 2D detection output files ''' with open(det_filename, 'r') as fn: results = pickle.load(fn) id_list = results['id_list'] type_list = results['type_list'] box2d_list = results['box2d_list'] prob_list = results['prob_list'] return id_list, type_list, box2d_list, prob_list def extract_frustum_data_rgb_detection(det_filename, split, output_filename, type_whitelist=['Car'], img_height_threshold=5, lidar_point_threshold=1): ''' Extract point clouds in frustums extruded from 2D detection boxes. Update: Lidar points and 3d boxes are in *rect camera* coord system (as that in 3d box label files) Input: det_filename: string, each line is img_path typeid confidence xmin ymin xmax ymax split: string, either trianing or testing output_filename: string, the name for output .pickle file type_whitelist: a list of strings, object types we are interested in. img_height_threshold: int, neglect image with height lower than that. lidar_point_threshold: int, neglect frustum with too few points. Output: None (will write a .pickle file to the disk) ''' dataset = kitti_object(os.path.join(ROOT_DIR, 'data/kitti'), split=split) if det_filename.split('.')[-1] == 'pkl': det_id_list, det_type_list, det_box2d_list, det_prob_list = \ read_det_pkl_file(det_filename) else: det_id_list, det_type_list, det_box2d_list, det_prob_list = \ read_det_file(det_filename) cache_id = -1 cache = None id_list = [] type_list = [] box2d_list = [] prob_list = [] input_list = [] # channel number = 4, xyz,intensity in rect camera coord frustum_angle_list = [] # angle of 2d box center from pos x-axis calib_list = [] for det_idx in range(len(det_id_list)): data_idx = det_id_list[det_idx] print('det idx: %d/%d, data idx: %d' % (det_idx, len(det_id_list), data_idx)) if cache_id != data_idx: calib = dataset.get_calibration(data_idx) # 3 by 4 matrix pc_velo = dataset.get_lidar(data_idx) pc_rect = np.zeros_like(pc_velo) pc_rect[:, 0:3] = calib.project_velo_to_rect(pc_velo[:, 0:3]) pc_rect[:, 3] = pc_velo[:, 3] img = dataset.get_image(data_idx) img_height, img_width, img_channel = img.shape _, pc_image_coord, img_fov_inds = get_lidar_in_image_fov( pc_velo[:, 0:3], calib, 0, 0, img_width, img_height, True) cache = [calib, pc_rect, pc_image_coord, img_fov_inds] cache_id = data_idx else: calib, pc_rect, pc_image_coord, img_fov_inds = cache if det_type_list[det_idx] not in type_whitelist: continue # 2D BOX: Get pts rect backprojected det_box2d = det_box2d_list[det_idx].copy() det_box2d[[0, 2]] = np.clip(det_box2d[[0, 2]], 0, img_width - 1) det_box2d[[1, 3]] = np.clip(det_box2d[[1, 3]], 0, img_height - 1) xmin, ymin, xmax, ymax = det_box2d box_fov_inds = (pc_image_coord[:, 0] < xmax) & \ (pc_image_coord[:, 0] >= xmin) & \ (pc_image_coord[:, 1] < ymax) & \ (pc_image_coord[:, 1] >= ymin) box_fov_inds = box_fov_inds & img_fov_inds pc_in_box_fov = pc_rect[box_fov_inds, :] pc_box_image_coord = pc_image_coord[box_fov_inds, :] # Get frustum angle (according to center pixel in 2D BOX) box2d_center = np.array([(xmin + xmax) / 2.0, (ymin + ymax) / 2.0]) uvdepth = np.zeros((1, 3)) uvdepth[0, 0:2] = box2d_center uvdepth[0, 2] = 20 # some random depth box2d_center_rect = calib.project_image_to_rect(uvdepth) frustum_angle = -1 * np.arctan2(box2d_center_rect[0, 2], box2d_center_rect[0, 0]) # Pass objects that are too small if ymax - ymin < img_height_threshold or xmax - xmin < 1 or \ len(pc_in_box_fov) < lidar_point_threshold: continue id_list.append(data_idx) type_list.append(det_type_list[det_idx]) box2d_list.append(np.array([xmin, ymin, xmax, ymax])) prob_list.append(det_prob_list[det_idx]) input_list.append(pc_in_box_fov.astype(np.float32, copy=False)) frustum_angle_list.append(frustum_angle) calib_list.append(calib.calib_dict) with open(output_filename, 'wb') as fp: pickle.dump(id_list, fp, -1) pickle.dump(box2d_list, fp, -1) pickle.dump(input_list, fp, -1) pickle.dump(type_list, fp, -1) pickle.dump(frustum_angle_list, fp, -1) pickle.dump(prob_list, fp, -1) pickle.dump(calib_list, fp, -1) print('total_objects %d' % len(id_list)) print('save in {}'.format(output_filename)) def write_2d_rgb_detection(det_filename, split, result_dir): ''' Write 2D detection results for KITTI evaluation. Convert from Wei's format to KITTI format. Input: det_filename: string, each line is img_path typeid confidence xmin ymin xmax ymax split: string, either trianing or testing result_dir: string, folder path for results dumping Output: None (will write <xxx>.txt files to disk) Usage: write_2d_rgb_detection("val_det.txt", "training", "results") ''' dataset = kitti_object(os.path.join(ROOT_DIR, 'data/kitti'), split) det_id_list, det_type_list, det_box2d_list, det_prob_list = \ read_det_file(det_filename) # map from idx to list of strings, each string is a line without \n results = {} for i in range(len(det_id_list)): idx = det_id_list[i] typename = det_type_list[i] box2d = det_box2d_list[i] prob = det_prob_list[i] output_str = typename + " -1 -1 -10 " output_str += "%f %f %f %f " % (box2d[0], box2d[1], box2d[2], box2d[3]) output_str += "-1 -1 -1 -1000 -1000 -1000 -10 %f" % (prob) if idx not in results: results[idx] = [] results[idx].append(output_str) if not os.path.exists(result_dir): os.mkdir(result_dir) output_dir = os.path.join(result_dir, 'data') if not os.path.exists(output_dir): os.mkdir(output_dir) for idx in results: pred_filename = os.path.join(output_dir, '%06d.txt' % (idx)) fout = open(pred_filename, 'w') for line in results[idx]: fout.write(line + '\n') fout.close() if __name__ == '__main__': parser = argparse.ArgumentParser() parser.add_argument('--gen_train', action='store_true', help='Generate train split frustum data with perturbed GT 2D boxes') parser.add_argument('--gen_val', action='store_true', help='Generate val split frustum data with GT 2D boxes') parser.add_argument('--gen_val_rgb_detection', action='store_true', help='Generate val split frustum data with RGB detection 2D boxes') parser.add_argument('--car_only', action='store_true', help='Only generate cars') parser.add_argument('--people_only', action='store_true', help='Only generate peds and cycs') parser.add_argument('--save_dir', default=None, type=str, help='data directory to save data') args = parser.parse_args() np.random.seed(3) if args.save_dir is None: save_dir = 'kitti/data/pickle_data' else: save_dir = args.save_dir if not os.path.exists(save_dir): os.makedirs(save_dir) if args.car_only: type_whitelist = ['Car'] output_prefix = 'frustum_caronly_' elif args.people_only: type_whitelist = ['Pedestrian', 'Cyclist'] output_prefix = 'frustum_pedcyc_' else: type_whitelist = ['Car', 'Pedestrian', 'Cyclist'] output_prefix = 'frustum_carpedcyc_' if args.gen_train: extract_frustum_data( os.path.join(BASE_DIR, 'image_sets/train.txt'), 'training', os.path.join(save_dir, output_prefix + 'train.pickle'), perturb_box2d=True, augmentX=5, type_whitelist=type_whitelist) if args.gen_val: extract_frustum_data( os.path.join(BASE_DIR, 'image_sets/val.txt'), 'training', os.path.join(save_dir, output_prefix + 'val.pickle'), perturb_box2d=False, augmentX=1, type_whitelist=type_whitelist) if args.gen_val_rgb_detection: extract_frustum_data_rgb_detection( os.path.join(BASE_DIR, 'rgb_detections/rgb_detection_val.txt'), 'training', os.path.join(save_dir, output_prefix + 'val_rgb_detection.pickle'), type_whitelist=type_whitelist)