prueba_cocoapi.py

from pycocotools.coco import COCO
import numpy as np
import skimage.io as io
import matplotlib.pyplot as plt
import pylab
pylab.rcParams['figure.figsize'] = (8.0, 10.0)

dataDir = './coco'
dataType = 'val2014'
annFile = '{}/annotations/instances_{}.json'.format(dataDir, dataType)

# initialize COCO api for instance annotations
coco=COCO(annFile)

# display COCO categories and supercategories
cats = coco.loadCats(coco.getCatIds())
nms=[cat['name'] for cat in cats]
print('COCO categories: \n{}\n'.format(' '.join(nms)))

nms = set([cat['supercategory'] for cat in cats])
print('COCO supercategories: \n{}'.format(' '.join(nms)))

# get all images containing given categories, select one at random
catIds = coco.getCatIds(catNms=['bird']);
imgIds = coco.getImgIds(catIds=catIds);
# imgIds = coco.getImgIds(imgIds = [285])
#img = coco.loadImgs(imgIds[0])[0]
img = coco.loadImgs(imgIds[np.random.randint(0,len(imgIds))])[0]

I = io.imread(img['coco_url'])

# load and display instance annotations
plt.imshow(I); plt.axis('off')
annIds = coco.getAnnIds(imgIds=img['id'], catIds=catIds, iscrowd=None)
anns = coco.loadAnns(annIds)
coco.showAnns(anns)
print(len(anns))
plt.show()