create structure for singlelabel pictures

from pycocotools.coco import COCO

import numpy as np

import skimage.io as io

import matplotlib.pyplot as plt

import pylab

import shutil

import os

coco = COCO('../../cocoapi/annotations/train/instances_train2017.json')

cats = coco.loadCats(coco.getCatIds())

nms = [cat['name'] for cat in cats]

for category in nms:

    catIds = coco.getCatIds(catNms=[category])

    imgIds = coco.getImgIds(catIds=catIds)

    directory = '../../cocoapi/train_all_objects/'+category

    if not os.path.exists(directory):

        os.makedirs(directory)

    for pic in imgIds:

        name = coco.loadImgs(pic)[0]['file_name']

        shutil.copy2('../../cocoapi/images/train/' + name, directory + '/' + name)