kitti Odometry數(shù)據(jù)集固耘，帶位置真值的數(shù)據(jù)，包含11個(gè)場(chǎng)景词身，但可惜只對(duì)齊了圖像和激光數(shù)據(jù)厅目，沒有oxts數(shù)據(jù)，也就是沒有rtk法严、imu等數(shù)據(jù)损敷，對(duì)于做vio、lio等任務(wù)就沒法搞了深啤，好在數(shù)據(jù)說明里有寫到這11個(gè)場(chǎng)景對(duì)應(yīng)的raw數(shù)據(jù)拗馒，如下：

seq_map = {
    "00": {"name": "2011_10_03_drive_0027", "start": 0, "end": 4540},
    "01": {"name": "2011_10_03_drive_0042", "start": 0, "end": 1100},
    "02": {"name": "2011_10_03_drive_0034", "start": 0, "end": 4660},
    "03": {"name": "2011_09_26_drive_0067", "start": 0, "end": 800},
    "04": {"name": "2011_09_30_drive_0016", "start": 0, "end": 270},
    "05": {"name": "2011_09_30_drive_0018", "start": 0, "end": 2760},
    "06": {"name": "2011_09_30_drive_0020", "start": 0, "end": 1100},
    "07": {"name": "2011_09_30_drive_0027", "start": 0, "end": 1100},
    "08": {"name": "2011_09_30_drive_0028", "start": 1100, "end": 5170},
    "09": {"name": "2011_09_30_drive_0033", "start": 0, "end": 1590},
    "10": {"name": "2011_09_30_drive_0034", "start": 0, "end": 1200}
}

有了raw數(shù)據(jù)，就有了oxts數(shù)據(jù)了溯街，只要基于時(shí)間戳做個(gè)對(duì)齊就行了诱桂，由于想要100hz的oxts數(shù)據(jù)洋丐，所以選擇unsync的raw數(shù)據(jù)，sync的raw數(shù)據(jù)只有10hz
還有大神支出raw里的oxts數(shù)據(jù)時(shí)間戳存在跳變情況挥等，需要做些處理友绝，詳見：https://zhuanlan.zhihu.com/p/75672946
https://zhuanlan.zhihu.com/p/115562083

我實(shí)現(xiàn)的一個(gè)處理oxts時(shí)間戳跳變情況函數(shù)，可以參考下

def load_timestamps(timestamps_file):
    timestamps = []
    with open(timestamps_file, 'r') as f:
        for line in f.readlines():
            # NB: datetime only supports microseconds, but KITTI timestamps
            # give nanoseconds, so need to truncate last 4 characters to
            # get rid of \n (counts as 1) and extra 3 digits
            t = dt.datetime.strptime(line[:-4], '%Y-%m-%d %H:%M:%S.%f')
            t = dt.datetime.timestamp(t)
            timestamps.append(t)
    return timestamps


def load_sync_timestamps(timestamps_file, std_dt=0.01):
    max_dt = std_dt * 1.5
    timestamps = np.array(load_timestamps(timestamps_file))
    x = np.arange(0, len(timestamps))

    last_timestamp = timestamps[:-1]
    curr_timestamp = timestamps[1:]
    dt = np.array(curr_timestamp - last_timestamp)  # 計(jì)算前后幀時(shí)間差

    print(timestamps_file)
    print("dt > {}: \n{}".format(max_dt, dt[dt > max_dt]))
    dt = dt.tolist()
    dt.append(std_dt)
    dt = np.array(dt)
    unsync_x = x[dt > max_dt]
    print("dt > {}: \n{}".format(max_dt, unsync_x))
    for i in unsync_x:
        succ = False
        # 向前對(duì)齊
        while (not succ):
            ii = i-1
            if ii < 0:
                break
            if ii not in unsync_x:
                for j in range(ii+1, i+1):
                    timestamps[j] = timestamps[j-1] + std_dt
                succ = True
                break
        # 向后對(duì)齊
        while (not succ):
            ii = i+1
            if ii >= len(timestamps):
                break
            if ii not in unsync_x:
                for j in range(ii, i, -1):
                    timestamps[j-1] = timestamps[j] - std_dt
                succ = True
                break
        if not succ:
            print("cannot sync timestamp", i, timestamps[i], dt[i])
    return timestamps

對(duì)齊邏輯也簡單粗暴

def concat_oxts(oxts_timestamps, extract_raw_dir, start_time, end_time, out_file):
    oxts_data = []
    for idx, oxts_t in enumerate(oxts_timestamps):
        if oxts_t < start_time:
            continue
        if oxts_t > end_time:
            break
        oxts_file = os.path.join(
            extract_raw_dir, "oxts", "data", "{:0>10d}.txt".format(idx))
        if not os.path.exists(oxts_file):
            print("oxts file not exists", oxts_file)
            continue
        with open(oxts_file, "r") as f:
            for line in f.readlines():
                oxts_data.append(line)
    os.makedirs(os.path.dirname(out_file), exist_ok=True)
    with open(out_file, "w") as f:
        f.writelines(oxts_data)


if __name__ == "__main__":
    os.makedirs(oxts_out_dir, exist_ok=True)
    # 對(duì)齊時(shí)間戳找到oxts數(shù)據(jù)
    for seq in seq_map:
        print(seq)
        post_raw_dir = seq_map[seq]["name"][:10]
        extract_raw_dir = os.path.join(
            raw_dir, post_raw_dir, seq_map[seq]["name"] + "_extract")
        if not os.path.exists(extract_raw_dir):
            print("raw seq data not exists", extract_raw_dir)
            continue

        start_idx = seq_map[seq]["start"]
        end_idx = seq_map[seq]["end"]
        image_timestamps_file = os.path.join(
            extract_raw_dir, "image_02", 'timestamps.txt')
        image_timestamps = load_sync_timestamps(image_timestamps_file, 0.1)

        # 扣出對(duì)應(yīng)時(shí)間戳內(nèi)的oxts數(shù)據(jù)
        oxts_timestamps_file = os.path.join(
            extract_raw_dir, "oxts", 'timestamps.txt')
        oxts_timestamps = load_sync_timestamps(oxts_timestamps_file, 0.01)
        # 上一幀到當(dāng)前幀之間的oxts數(shù)據(jù)
        for i in range(start_idx, end_idx + 1):
            if i == 0:
                start_time = image_timestamps[i] - 0.1
            else:
                start_time = image_timestamps[i-1]
            end_time = image_timestamps[i]
            oxts_file = os.path.join(
                oxts_out_dir, seq, "{:0>10d}.txt".format(i-start_idx))
            concat_oxts(oxts_timestamps, extract_raw_dir,
                        start_time, end_time, oxts_file)

提供一個(gè)我對(duì)齊好的oxts數(shù)據(jù)肝劲，由于03對(duì)應(yīng)的2011_09_26_drive_0067數(shù)據(jù)官網(wǎng)無法下載迁客，所以沒有03對(duì)應(yīng)的oxts數(shù)據(jù)

鏈接: https://pan.baidu.com/s/1CR8aaNB83cWC0nrIatag5w 提取碼: gi9c