MTSD/annotations/mtsd_v2_fully_annotated/visualize_example.py

import json
import os
from PIL import Image, ImageDraw, ImageColor, ImageFont

def load_annotation(image_key):
 with open(os.path.join('annotations', '{:s}.json'.format(image_key)), 'r') as fid:
 anno = json.load(fid)
 return anno


def visualize_gt(image_key, anno, color='green', alpha=125, font=None):
 try:
 font = ImageFont.truetype('arial.ttf', 15)
 except:
 print('Falling back to default font...')
 font = ImageFont.load_default()
 
 with Image.open(os.path.join('images', '{:s}.jpg'.format(image_key))) as img:
 img = img.convert('RGBA')
 img_draw = ImageDraw.Draw(img)

 rects = Image.new('RGBA', img.size)
 rects_draw = ImageDraw.Draw(rects)

 for obj in anno['objects']:
 x1 = obj['bbox']['xmin']
 y1 = obj['bbox']['ymin']
 x2 = obj['bbox']['xmax']
 y2 = obj['bbox']['ymax']

 color_tuple = ImageColor.getrgb(color)
 if len(color_tuple) == 3:
 color_tuple = color_tuple + (alpha,)
 else:
 color_tuple[-1] = alpha

 rects_draw.rectangle((x1+1, y1+1, x2-1, y2-1), fill=color_tuple)
 img_draw.line(((x1, y1), (x2, y1), (x2, y2), (x1, y2), (x1, y1)), fill='black', width=1)

 class_name = obj['label']
 img_draw.text((x1 + 5, y1 + 5), class_name, font=font)

 img = Image.alpha_composite(img, rects)

 return img


if __name__ == '__main__':
 image_key = 'Bh36Ed4HBJatMpSNnFTgTw'

 # load the annotation json
 anno = load_annotation(image_key)

 # visualize traffic sign boxes on the image
 vis_img = visualize_gt(image_key, anno)
 vis_img.show()