获取 COCO 数据集分布信息 | Patrick's Space

使用 COCO API 来获得数据集中的数据分布信息，参考CSDN 文章。

from pycocotools.coco import COCO

coco=COCO(PATH_TO_COCO_JSON)

# 获取所有类别对应的名称与 id，一共有 80 类，id 号则是 1~90
cat_info = [(c['id'], c['name']) for c in coco.cats.values()]

for cat_id, cat_name in cat_info:
    anns = coco.catToImgs[cat_id]
    print("{} | {} | {:.2%} | {} | {:.2%}".format(cat_name, len(set(anns)), len(set(anns)) / len(coco.imgs), len(anns), len(anns) / len(coco.anns)))

其中 val2017 分布如下：

类别名	图像数	类别比例	框数	框比例
person	2693	53.86%	11004	29.92%
bicycle	149	2.98%	316	0.86%
car	535	10.70%	1932	5.25%
motorcycle	159	3.18%	371	1.01%
airplane	97	1.94%	143	0.39%
bus	189	3.78%	285	0.77%
train	157	3.14%	190	0.52%
truck	250	5.00%	415	1.13%
boat	121	2.42%	430	1.17%
traffic light	191	3.82%	637	1.73%
fire hydrant	86	1.72%	101	0.27%
stop sign	69	1.38%	75	0.20%
parking meter	37	0.74%	60	0.16%
bench	235	4.70%	413	1.12%
bird	125	2.50%	440	1.20%
cat	184	3.68%	202	0.55%
dog	177	3.54%	218	0.59%
horse	128	2.56%	273	0.74%
sheep	65	1.30%	361	0.98%
cow	87	1.74%	380	1.03%
elephant	89	1.78%	255	0.69%
bear	49	0.98%	71	0.19%
zebra	85	1.70%	268	0.73%
giraffe	101	2.02%	232	0.63%
backpack	228	4.56%	371	1.01%
umbrella	174	3.48%	413	1.12%
handbag	292	5.84%	540	1.47%
tie	145	2.90%	254	0.69%
suitcase	105	2.10%	303	0.82%
frisbee	84	1.68%	115	0.31%
skis	120	2.40%	241	0.66%
snowboard	49	0.98%	69	0.19%
sports ball	169	3.38%	263	0.72%
kite	91	1.82%	336	0.91%
baseball bat	97	1.94%	146	0.40%
baseball glove	100	2.00%	148	0.40%
skateboard	127	2.54%	179	0.49%
surfboard	149	2.98%	269	0.73%
tennis racket	167	3.34%	225	0.61%
bottle	379	7.58%	1025	2.79%
wine glass	110	2.20%	343	0.93%
cup	390	7.80%	899	2.44%
fork	155	3.10%	215	0.58%
knife	181	3.62%	326	0.89%
spoon	153	3.06%	253	0.69%
bowl	314	6.28%	626	1.70%
banana	103	2.06%	379	1.03%
apple	76	1.52%	239	0.65%
sandwich	98	1.96%	177	0.48%
orange	85	1.70%	287	0.78%
broccoli	71	1.42%	316	0.86%
carrot	81	1.62%	371	1.01%
hot dog	51	1.02%	127	0.35%
pizza	153	3.06%	285	0.77%
donut	62	1.24%	338	0.92%
cake	124	2.48%	316	0.86%
chair	580	11.60%	1791	4.87%
couch	195	3.90%	261	0.71%
potted plant	172	3.44%	343	0.93%
bed	149	2.98%	163	0.44%
dining table	501	10.02%	697	1.90%
toilet	149	2.98%	179	0.49%
tv	207	4.14%	288	0.78%
laptop	183	3.66%	231	0.63%
mouse	88	1.76%	106	0.29%
remote	145	2.90%	283	0.77%
keyboard	106	2.12%	153	0.42%
cell phone	214	4.28%	262	0.71%
microwave	54	1.08%	55	0.15%
oven	115	2.30%	143	0.39%
toaster	8	0.16%	9	0.02%
sink	187	3.74%	225	0.61%
refrigerator	101	2.02%	126	0.34%
book	230	4.60%	1161	3.16%
clock	204	4.08%	267	0.73%
vase	137	2.74%	277	0.75%
scissors	28	0.56%	36	0.10%
teddy bear	94	1.88%	191	0.52%
hair drier	9	0.18%	11	0.03%
toothbrush	34	0.68%	57	0.15%

train2017 分布如下

类别名	图像数	类别比例	框数	框比例
person	64115	54.20%	262465	30.52%
bicycle	3252	2.75%	7113	0.83%
car	12251	10.36%	43867	5.10%
motorcycle	3502	2.96%	8725	1.01%
airplane	2986	2.52%	5135	0.60%
bus	3952	3.34%	6069	0.71%
train	3588	3.03%	4571	0.53%
truck	6127	5.18%	9973	1.16%
boat	3025	2.56%	10759	1.25%
traffic light	4139	3.50%	12884	1.50%
fire hydrant	1711	1.45%	1865	0.22%
stop sign	1734	1.47%	1983	0.23%
parking meter	705	0.60%	1285	0.15%
bench	5570	4.71%	9838	1.14%
bird	3237	2.74%	10806	1.26%
cat	4114	3.48%	4768	0.55%
dog	4385	3.71%	5508	0.64%
horse	2941	2.49%	6587	0.77%
sheep	1529	1.29%	9509	1.11%
cow	1968	1.66%	8147	0.95%
elephant	2143	1.81%	5513	0.64%
bear	960	0.81%	1294	0.15%
zebra	1916	1.62%	5303	0.62%
giraffe	2546	2.15%	5131	0.60%
backpack	5528	4.67%	8720	1.01%
umbrella	3968	3.35%	11431	1.33%
handbag	6841	5.78%	12354	1.44%
tie	3810	3.22%	6496	0.76%
suitcase	2402	2.03%	6192	0.72%
frisbee	2184	1.85%	2682	0.31%
skis	3082	2.61%	6646	0.77%
snowboard	1654	1.40%	2685	0.31%
sports ball	4262	3.60%	6347	0.74%
kite	2261	1.91%	9076	1.06%
baseball bat	2506	2.12%	3276	0.38%
baseball glove	2629	2.22%	3747	0.44%
skateboard	3476	2.94%	5543	0.64%
surfboard	3486	2.95%	6126	0.71%
tennis racket	3394	2.87%	4812	0.56%
bottle	8501	7.19%	24342	2.83%
wine glass	2533	2.14%	7913	0.92%
cup	9189	7.77%	20650	2.40%
fork	3555	3.01%	5479	0.64%
knife	4326	3.66%	7770	0.90%
spoon	3529	2.98%	6165	0.72%
bowl	7111	6.01%	14358	1.67%
banana	2243	1.90%	9458	1.10%
apple	1586	1.34%	5851	0.68%
sandwich	2365	2.00%	4373	0.51%
orange	1699	1.44%	6399	0.74%
broccoli	1939	1.64%	7308	0.85%
carrot	1683	1.42%	7852	0.91%
hot dog	1222	1.03%	2918	0.34%
pizza	3166	2.68%	5821	0.68%
donut	1523	1.29%	7179	0.83%
cake	2925	2.47%	6353	0.74%
chair	12774	10.80%	38491	4.48%
couch	4423	3.74%	5779	0.67%
potted plant	4452	3.76%	8652	1.01%
bed	3682	3.11%	4192	0.49%
dining table	11837	10.01%	15714	1.83%
toilet	3353	2.83%	4157	0.48%
tv	4561	3.86%	5805	0.67%
laptop	3524	2.98%	4970	0.58%
mouse	1876	1.59%	2262	0.26%
remote	3076	2.60%	5703	0.66%
keyboard	2115	1.79%	2855	0.33%
cell phone	4803	4.06%	6434	0.75%
microwave	1547	1.31%	1673	0.19%
oven	2877	2.43%	3334	0.39%
toaster	217	0.18%	225	0.03%
sink	4678	3.95%	5610	0.65%
refrigerator	2360	2.00%	2637	0.31%
book	5332	4.51%	24715	2.87%
clock	4659	3.94%	6334	0.74%
vase	3593	3.04%	6613	0.77%
scissors	947	0.80%	1481	0.17%
teddy bear	2140	1.81%	4793	0.56%
hair drier	189	0.16%	198	0.02%
toothbrush	1007	0.85%	1954	0.23%